TRACE CARBON 22nd of May 2020 An online What’s at stake  workshop for Art is the trace of perfume Meets Radical that has been released Openness 2020 .“Base Faith”
 22nd of May 2020 
 Harney & Moten 14:00-17:00 Jamie Allen 
 w/ Caroline Sinders  #cyclesofcirculation The phrase “trace element” refers to materials and chemicals with very low concentrations. Carbon is literally everywhere on earth — it is anything but “trace” as an element — and yet tracking its flows and tracing its usage has become a global fixation, through marketisation, logistification, footprinting and storytelling. This traceability of materials — the ability to identify their history, distribution, location, and application — has become a main preoccupation of contemporary ecological, political, epidemiological, conspiratorial, and global supply chain practices (forming, for example, part of the ISO 9000 standard). A “trace amount” for the chemist is one whose average concentration is less than 100 atomic parts per million (ppm); for the biochemist it is a dietary element needed in extremely small quantities to sustain life; for the geochemist it is a quantity that makes 0.1% of a rock's composition. The technologies we hope to account for, manage and engineer carbon (dioxide) are driven by the things that drive all human technological development — human impulses, desires, values, systems, institutions, economics, power equalities and inequalities. There are personal stories in the re-composition of carbon as a new kind of traceable currency, ambiguous stories of human attentions and passions, greed and interests, benevolence and care for the element number 6. If the road to hell is indeed paved with good intentions, the very least we can do is pave them with carbon sequestering cement. The workshop Trace Carbon is largely a discussion format, framed around the markets and techniques for carbon measurement and management currently proposed and underway in environmental, ecological, governmental, industrial and technological contexts. There will be a short assignment and AFK reflections and assignments done by the group during the approximately 4-hour session. The workshop features presentations of ongoing related work, and a ‘reader’. The workshop itself will involve recordings of ‘carbon traces’ — stories by and with participants — to be published in some form through the Cycles of Circulation project, compiled and edited by Caroline Sinders. 2 #cyclesofcirculation Levi, P. (1984). “Carbon” from “The Periodic Table”. New York: Schocken Books.  p. 4 “Carbon” by Primo Levi is one part of a book of short stories that Levi wrote — it’s a book of semi- autobiographical fictions based on scenes from his life as a chemist, called “The Periodic Table”.  Described as a poetic fantasy, “Carbon” is one entry in this table, about the single life of an atom as its ‘main character.’ Falkowski, P., et. al (2000). The global carbon cycle: a test of our knowledge of earth as a p. 11 system. Science, 290(5490), 291-296.
 The cycling and measurement — containment, really — of carbon as an element tests the limits of what human knowledge is and can do. This is an academic paper on the increases of CO2 due to human activities, starting from the Industrial Revolution until now, outlining how far the scientific metaphor of ‘earth as a system’ can be taken. Harney, S. M. & Moten, F. (2017). Base faith. E-Flux Journal, (86), 1. p. 18 A poetic, research based essay on processes and systems of the earth, in relationship to futures on the planet, pasts and futures of ownership and capital. “What’s at stake is the trace of perfume that has been released.” Callon, M. (2009). Civilizing markets: Carbon trading between in vitro and in vivo experiments. p. 26 Accounting, organizations and so- ciety, 34(3-4), 535-548. 
 
 This journal article by the famed ‘less radical’ Latour, Michel Callon talks about ‘carbon markets’, rather early in their consideration by people like Callon. Carbon markets set a limit or cap of emissions and then allow groups to trade their ‘left over’ emissions they have used. This essay focuses on carbon markets as ‘on-going collective experiments’, which they still are. Baena-Moreno, et. al (2019). Carbon capture and utilization technologies: A literature review p. 41 and recent advances. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 41(12), 1403-1433.  This is a straightforward, if technical academic paper on a list of carbon capture and utilization technologies and applications. The paper covers different ends of the carbon capture spectrum —  from R&D, academic studies, to commercial uses of carbon dioxide. Suess, S. Distributed Resistance, Streamlined Silk. Synoptique.ca, https://synoptique.ca/wp- p. 73 content/up- loads/2019/03/8.1-Suess-1.pdf  This essay by Solveig Suess talks about globalised flows of materials, including carbon, particularly concerned with logistics and the tracing of this materiality. Suess deals as well with the conceptual tools of new materialism that focus on the mechanics which extract both logistics and industry for capital, and their impacts on environments. MacKenzie, D. (2009). Making things the same: Gases, emission rights and the politics of p. 89 carbon markets. Accounting, organizations and society, 34(3-4), 440-455.  A paper on the ways that markets level things out and create means of exchange for incommensurate elements, materials and value. MacKenzie’s work analyses carbon markets specifically, how these markets were created, and how something as ephemeral as atmospheric gases have come to be measured and analyzed through the “politics of market design.” Levi, P. (1984). “Carbon” from “The Periodic Table”. New York: Schocken Books.  “Carbon” by Primo Levi is one part of a book of short stories that Levi wrote — it’s a book of semi-autobiographical fictions based on scenes from his life as a chemist, called “The Periodic Table”.  Described as a poetic fantasy, “Carbon” is one entry in this table, about the single life of an atom as its ‘main character.’ 4 #cyclesofcirculation Carbon (excerpt) The Periodic Table, Primo Levi . . . Is it right to speak of a “particular” atom of carbon? For the chemist there exist some doubts, because until 1970 he did not have the techniques permitting him to see, or in any event isolate, a single atom; no doubts exist for the narrator, who therefore sets out to narrate. Our character lies for hundreds of millions of years, bound to three atoms of oxygen and one of calcium, in the form of limestone: it already has a very long cosmic history behind it, but we shall ignore it. For it time does not exist, or exists only in the form of sluggish variations in temperature, daily or seasonal, if, for the good fortune of this tale, its position is not too far from the earth’s surface. Its existence, whose monotony cannot be thought of without horror, is a pitiless alternation of hots and colds, that is, of oscillations (always of equal frequency) a trifle more restricted and a trifle more ample: an imprisonment, for this potentially living personage, worthy of the Catholic Hell. To it, until this moment, the present tense is suited, which is that of description, rather than the past tense, which is that of narration—it is congealed in an eternal present, barely scratched by the moderate quivers of thermal agitation. But, precisely for the good fortune of the narrator, whose story could otherwise have come to an end, the limestone rock ledge of which the atom forms a part lies on the surface. It lies within reach of man and his pickax (all honor to the pickax and its modern equivalents; they are still the most important intermediaries in the millennial dialogue between the elements and man): at any moment—which I, the narrator, decide out of pure caprice to be the year 1840—a blow of the pickax detached it and sent it on its way to the lime kiln, plunging it into the world of things that change. It was roasted until it separated from the calcium, which remained so to speak with its feet on the ground and went to meet a less brilliant destiny, which we shall not narrate. Still firmly clinging to two of its three former oxygen companions, it issued from the chimney and took the path of the air. Its story, which once was immobile, now turned tumultuous. It was caught by the wind, flung down on the earth, lifted ten kilometers 1 5 #cyclesofcirculation high. It was breathed in by a falcon, descending into its precipitous lungs, but did not penetrate its rich blood and was expelled. It dissolved three times in the water of the sea, once in the water of a cascading torrent, and again was expelled. It traveled with the wind for eight years: now high, now low, on the sea and among the clouds, over forests, deserts, and limitless expanses of ice; then it stumbled into capture and the organic adventure. Carbon, in fact, is a singular element: it is the only element that can bind itself in long stable chains without a great expense of energy, and for life on earth (the only one we know so far) precisely long chains are required. Therefore carbon is the key element of living substance: but its promotion, its entry into the living world, is not easy and must follow an obligatory, intricate path, which has been clarified (and not yet definitively) only in recent years. If the elaboration of carbon were not a common daily occurrence, on the scale of billions of tons a week, wherever the green of a leaf appears, it would by full right deserve to be called a miracle. The atom we are speaking of, accompanied by its two satellites which maintained it in a gaseous state, was therefore borne by the wind along a row of vines in the year 1848. It had the good fortune to brush against a leaf, penetrate it, and be nailed there by a ray of the sun. If my language here becomes imprecise and allusive, it is not only because of my ignorance: this decisive event, this instantaneous work a tre—of the carbon dioxide, the light, and the vegetal greenery—has not yet been described in definitive terms, and perhaps it will not be for a long time to come, so di↵erent is it from that other “organic” chemistry which is the cumbersome, slow, and ponderous work of man: and yet this refined, minute, and quick-witted chem- istry was “invented” two or three billion years ago by our silent sisters, the plants, which do not experiment and do not discuss, and whose temperature is identical to that of the environment in which they live. If to comprehend is the same as forming an image, we will never form an image of a happening whose scale is a millionth of a millimeter, whose rhythm is a millionth of a second, and whose protagonists are in their essence invisible. Every verbal description must be inadequate, and one will be as good as the next, so let us settle for the following description. Our atom of carbon enters the leaf, colliding with other innumerable (but here useless) molecules of nitrogen and oxygen. It adheres to a large and complicated molecule that activates it, and simultaneously receives the decisive message from the sky, in the flashing form of a packet of solar light: in an instant, like an insect caught by a spider, it is separated from its oxygen, 2 6 #cyclesofcirculation combined with hydrogen and (one thinks) phosphorus, and finally inserted in a chain, whether long or short does not matter, but it is the chain of life. All this happens swiftly, in silence, at the temperature and pressure of the atmosphere, and gratis: dear colleagues, when we learn to do likewise we will be sicut Deus, and we will have also solved the problem of hunger in the world. But there is more and worse, to our shame and that of our art. Carbon dioxide, that is, the aerial form of the carbon of which we have up till now spoken: this gas which constitutes the raw material of life, the permanent store upon which all that grows draws, and the ultimate destiny of all flesh, is not one of the principal components of air but rather a ridiculous remnant, an “impurity,” thirty times less abundant than argon, which nobody even notices. The air contains 0.03 percent; if Italy was air, the only Italians fit to build life would be, for example, the fifteen thousand inhabitants of Milazzo in the province of Messina. This, on the human scale, is ironic acrobatics, a juggler’s trick, an incomprehensible display of omnipotence- arrogance, since from this ever renewed impurity of the air we come, we animals and we plants, and we the human species, with our four billion discordant opinions, our milleniums of history, our wars and shames, nobility and pride. In any event, our very presence on the planet becomes laughable in geometric terms: if all of humanity, about 250 million tons, were distributed in a layer of homogeneous thickness on all the emergent lands, the “stature of man“ would not be visible to the naked eye; the thickness one would obtain would be around sixteen thousandths of a millimeter. Now our atom is inserted: it is part of a structure, in an architectural sense; it has become related and tied to five companions so identical with it that only the fiction of the story permits me to distinguish them. It is a beautiful ring-shaped structure, an almost regular hexagon, which however is subjected to complicated exchanges and balances with the water in which it is dissolved; because by now it is dissolved in water, indeed in the sap of the vine, and this, to remain dissolved, is both the obligation and the privilege of all substances that are destined (I was about to say “wish”) to change. And if then anyone really wanted to find out why a ring, and why a hexagon, and why soluble in water, well, he need not worry: these are among the not many questions to which our doctrine can reply with a persuasive discourse, accessible to everyone, but out of place here. It has entered to form part of a molecule of glucose, just to speak plainly: a fate that is neither fish, flesh, nor fowl, which is intermediary, which prepares 3 7 #cyclesofcirculation it for its first contact with the animal world but does not authorize it to take on a higher responsibility: that of becoming part of a proteic edifice. Hence it travels, at the slow pace of vegetal juices, from the leaf through the pedicel and by the shoot to the trunk, and from here descends to the almost ripe bunch of grapes. What then follows is the province of the winemakers: we are only interested in pinpointing the fact that it escaped (to our advantage, since we would not know how to put it in words) the alcoholic fermentation, and reached the wine without changing its nature. It is the destiny of wine to be drunk, and it is the destiny of glucose to be oxidized. But it was not oxidized immediately: its drinker kept it in his liver for more than a week, well curled up and tranquil, as a reserve aliment for a sudden e↵ort; an e↵ort that he was forced to make the following Sunday, pursuing a bolting horse. Farewell to the hexagonal structure: in the space of a few instants the skein was unwound and became glucose again, and this was dragged by the bloodstream all the way to a minute muscle fiber in the thigh, and here brutally split into two molecules of lactic acid, the grim harbinger of fatigue: only later, some minutes after, the panting of the lungs was able to supply the oxygen necessary to quietly oxidize the latter. So a new molecule of carbon dioxide returned to the atmosphere, and a parcel of the energy that the sun had handed to the vine-shoot passed from the state of chemical energy to that of mechanical energy, and thereafter settled down in the slothful condition of heat, warming up imperceptibly the air moved by the running and the blood of the runner. “Such is life,” although rarely is it described in this manner: an inserting itself, a drawing o↵ to its advantage, a parasitizing of the downward course of energy, from its noble solar form to the degraded one of low- temperature heat. In this downward course, which leads to equilibrium and thus death, life draws a bend and nests in it. Our atom is again carbon dioxide, for which we apologize: this too is an obligatory passage; one can imagine and invent others, but on earth that’s the way it is. Once again the wind, which this time travels far; sails over the Apennines and the Adriatic, Greece, the Aegean, and Cyprus: we are over Lebanon, and the dance is repeated. The atom we are concerned with is now trapped in a structure that promises to last for a long time: it is the venerable trunk of a cedar, one of the last; it is passed again through the stages we have already described, and the glucose of which it is a part belongs, like the bead of a rosary, to a long chain of cellulose. This is no longer the hallucinatory and geological fixity of rock, this is no longer millions of years, but we can easily speak of centuries because the cedar is a tree of great longevity. It is 4 8 #cyclesofcirculation our whim to abandon it for a year or five hundred years: let us say that after twenty years (we are in 1868) a wood worm has taken an interest in it. It has dug its tunnel between the trunk and the bark, with the obstinate and blind voracity of its race; as it drills it grows, and its tunnel grows with it. There it has swallowed and provided a setting for the subject of this story; then it has formed a pupa, and in the spring it has come out in the shape of an ugly gray moth which is now drying in the sun, confused and dazzled by the splendor of the day. Our atom is in one of the insect’s thousand eyes, contributing to the summary and crude vision with which it orients itself in space. The insect is fecundated, lays its eggs, and dies: the small cadaver lies in the undergrowth of the woods, it is emptied of its fluids, but the chitin carapace resists for a long time, almost indestructible. The snow and sun return above it without injuring it: it is buried by the dead leaves and the loam, it has become a slough, a “thing,“ but the death of atoms, unlike ours, is never irrevocable. Here are at work the omnipresent, untiring, and invisible gravediggers of the undergrowth, the microorganisms of the humus. The carapace, with its eyes by now blind, has slowly disintegrated, and the ex-drinker, ex-cedar, ex-wood worm has once again taken wing. We will let it fly three times around the world, until 1960, and in justifica- tion of so long an interval in respect to the human measure we will point out that it is, however, much shorter than the average: which, we understand, is two hundred years. Every two hundred years, every atom of carbon that is not congealed in materials by now stable (such as, precisely, limestone, or coal, or diamond, or certain plastics) enters and reenters the cycle of life, through the narrow door of photosynthesis. Do other doors exist? Yes, some syntheses created by man; they are a title of nobility for man-the-maker, but until now their quantitative importance is negligible. They are doors still much narrower than that of the vegetal greenery; knowingly or not, man has not tried until now to compete with nature on this terrain, that is, he has not striven to draw from the carbon dioxide in the air the carbon that is necessary to nourish him, clothe him, warm him, and for the hundred other more sophisticated needs of modern life. He has not done it because he has not needed to: he has found, and is still finding (but for how many more decades?) gigantic reserves of carbon already organicized, or at least reduced. Besides the vegetable and animal worlds, these reserves are constituted by deposits of coal and petroleum: but these too are the inheritance of photo- synthetic activity carried out in distant epochs, so that one can well arm that photosynthesis is not only the sole path by which carbon becomes living 5 9 #cyclesofcirculation matter, but also the sole path by which the sun’s energy becomes chemically usable. It is possible to demonstrate that this completely arbitrary story is nevertheless true. I could tell innumerable other stories, and they would all be true: all literally true, in the nature of the transitions, in their order and data. The number of atoms is so great that one could always be found whose story coincides with any capriciously invented story. I could recount an endless number of stories about carbon atoms that become colors or per- fumes in flowers; of others which, from tiny algae to small crustaceans to fish, gradually return as carbon dioxide to the waters of the sea, in a perpetual, frightening round-dance of life and death, in which every devourer is immedi- ately devoured; of others which instead attain a decorous semi-eternity in the yellowed pages of some archival document, or the canvas of a famous painter; or those to which fell the privilege of forming part of a grain of pollen and left their fossil imprint in the rocks for our curiosity; of others still that descended to become part of the mysterious shape-messengers of the human seed, and participated in the subtle process of division, duplication, and fusion from which each of us is born. Instead, I will tell just one more story, the most secret, and I will tell it with the humility and restraint of him who knows from the start that his theme is desperate, his means feeble, and the trade of clothing facts in words is bound by its very nature to fail. It is again among us, in a glass of milk. It is inserted in a very complex, long chain, yet such that almost all of its links are acceptable to the human body. It is swallowed; and since every living structure harbors a savage distrust toward every contribution of any material of living origin, the chain is meticulously broken apart and the fragments, one by one, are accepted or rejected. One, the one that concerns us, crosses the intestinal threshold and enters the bloodstream: it migrates, knocks at the door of a nerve cell, enters, and supplants the carbon which was part of it. This cell belongs to a brain, and it is my brain, the brain of the me who is writing; and the cell in question, and within it the atom in question, is in charge of my writing, in a gigantic minuscule game which nobody has yet described. It is that which at this instant, issuing out of a labyrinthine tangle of yeses and nos, makes my hand run along a certain path on the paper, mark it with these volutes that are signs: a double snap, up and down, between two levels of energy, guides this hand of mine to impress on the paper this dot, here, this one. 6 10 #cyclesofcirculation Falkowski, P., et. al (2000). The global carbon cycle: a test of our knowledge of earth as a system. Science, 290(5490), 291-296.
 The cycling and measurement — containment, really — of carbon as an element tests the limits of what human knowledge is and can do. This is an academic paper on the increases of CO2 due to human activities, starting from the Industrial Revolution until now, outlining how far the scientific metaphor of ‘earth as a system’ can be taken. 11 #cyclesofcirculation S C I E N C E ’ S C O M P A S S ● R E V I E W R E V I E W : C L I M A T E C H A N G E The Global Carbon Cycle: A Test of Our Knowledge of Earth as a System P. Falkowski,1*† R. J. Scholes,2* E. Boyle,3‡ J. Canadell,4‡ D. Canfield,5‡ J. Elser,6‡ N. Gruber,7‡ K. Hibbard,8‡ P. Högberg,9‡ S. Linder,10‡ F. T. Mackenzie,11‡ B. Moore III,8‡ T. Pedersen,12‡ Y. Rosenthal,1‡ S. Seitzinger,1‡ V. Smetacek,13‡ W. Steffen14‡ over the past 420,000 years, the climate sys- Motivated by the rapid increase in atmospheric CO2 due to human activities since the tem has operated within a relatively con- Industrial Revolution, several international scientific research programs have analyzed strained domain of atmospheric CO2 and the role of individual components of the Earth system in the global carbon cycle. Our temperature (7, 8) (Fig. 1). In the CO2-tem- knowledge of the carbon cycle within the oceans, terrestrial ecosystems, and the perature phase space that characterized the atmosphere is sufficiently extensive to permit us to conclude that although natural preindustrial world, CO2 oscillated in processes can potentially slow the rate of increase in atmospheric CO2, there is no 100,000-year cycles by approximately 100 natural “savior” waiting to assimilate all the anthropogenically produced CO2 in the parts per million by volume (ppmv), between coming century. Our knowledge is insufficient to describe the interactions between about 180 and 280 ppmv. On millennial time the components of the Earth system and the relationship between the carbon cycle scales, changes in CO recorded in ice cores and other biogeochemical and climatological processes. Overcoming this limitation 2are highly correlated with changes in temper- requires a systems approach. ature (9). Although high-resolution analysis of ice cores suggests that there are periods in Earth’s history when temperature can change Over the past 200 years, human activ- generations. Given present trends in energy relatively sharply without a discernibleities have altered the global carbon demands, ample fossil fuel reserves, a lack of change in CO2 (7 ), the converse does notcycle significantly. Understanding global, concerted, alternative energy produc- appear to be true. the consequences of these activities in the tion strategies, and projections of human pop- Comparison of the present atmospheric coming decades is critical for formulating ulation growth, atmospheric CO2 concentra- concentration of CO2 with the ice core record economic, energy, technology, trade, and se- tions appear fated to increase throughout the reveals that we have left the domain that curity policies that will affect civilization for coming century (1, 2). The rate of change in defined the Earth system for the 420,000 atmospheric CO2 depends, however, not only years before the Industrial Revolution (10) 1Institute of Marine and Coastal Sciences, Rutgers on human activities but also on biogeochemi- (Fig. 1). Atmospheric CO2 concentration is University, 71 Dudley Road, New Brunswick, NJ 2 cal and climatological processes and their now nearly 100 ppmv higher, and has risen to08901, USA. Council of Scientific and Industrial Re- search, Environmental Division, Post Office Box 395, interactions with the carbon cycle. Here we that level at a rate at least 10 and possibly 100 Pretoria 0001, South Africa. 3Earth, Atmospheric, and examine some of the changes in biogeo- times faster than at any other time in the past Planetary Science Department, Massachusetts Insti- chemical and climatological processes con- 420,000 years. We have driven the Earth tute of Technology, 42 Carleton Street, Mail Code: comitant with alterations in the carbon and system from the tightly bounded domain of E34-258, Cambridge, MA 02142–1324, USA. 4Global Change and Terrestrial Ecosystems International nutrient cycles in the contemporary world, glacial-interglacial dynamics. Are we in a Project Office, Commonwealth Scientific and Indus- and compare these processes with our under- transition period to a new, stable domain? If trial Research Organisation Wildlife and Ecology, Post standing of the preceding 420,000 years of so, what are the main forcing factors and Office Box 284, Canberra, Australian Capital Territory, Earth’s history. feedbacks of this transition? What will be the 2601, Australia. 5Institute of Biological Sciences, Odense University, 5230 Odense, Denmark. 6Depart- climatological features of a new domain? ment of Zoology, Arizona State University, Temple, Entering Uncharted Waters What will be the responses and feedbacks of AZ 85287–1501, USA. 7Institute of Geophysics and Under the auspices of the International Geo- Earth’s ecosystems? How and when can and Planetary Physics and Department of Atmospheric sphere-Biosphere Programme (IGBP), sever- should we return to the preindustrial domain? Sciences, 5853 Slichter Hall, University of California, 8 al large international scientific studies have The active carbon reservoirs and theirLos Angeles, CA 90095–4996, USA. Institute for the Study of Earth, Oceans, Space, University of New focused on elucidating various aspects of the strengths. Atmospheric CO2 exchanges rap- Hampshire, Morse Hall, 39 College Road, Durham, NH global carbon cycle over the past decade (3). idly with oceans and terrestrial ecosystems 03824, USA. 9Department of Forest Ecology, Swedish These programs have helped address two ma- (11). The ratio between the rate at which University of Agricultural Sciences, S-901 83 Umea, 10 jor recurrent questions in the current debate these two reservoirs absorb atmospheric COSweden. Department for Production Ecology, Swed- 2 ish University of Agricultural Sciences, Post Office Box about global change: Can we distinguish be- and the rate of emissions determines the over- 7042, S750 07 Uppsala, Sweden. 11Department of tween anthropogenic perturbations and natu- all rate of change of atmospheric CO2. The Oceanography, SOEST, University of Hawaii, Honolu- ral variability in biogeochemical cycles and sink strength of the reservoirs determines the lu, HI, 96822, USA. 12Department of Earth and Ocean climate? And what is the sensitivity of capacity to absorb excess or anthropogenic Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada. 13Alfred Wegener Institute for Earth’s climate to changes in atmospheric CO2. During glacial-interglacial transitions, Polar and Marine Research, Am Handelshafen 12, CO2? We consider the two questions in the for example, the atmosphere acts to transfer 27570 Bremerhaven, Germany. 14IGBP Secretariat, context of the relatively recent geological carbon between terrestrial ecosystems and the Royal Swedish Academy of Sciences, Box 50005 Lilia history of Earth, for which we have robust oceans. The remarkable consistency of the Frescativagen 4, S-10405 Stockholm, Sweden. paleoclimatological proxies. upper and lower limits of the glacial-intergla- *Co-chairs of the International Geosphere-Biosphere Arrhenius recognized over 100 years ago cial atmospheric CO concentrations, and the Programme (IGBP) Working Group and lead authors. 2 †To whom correspondence should be addressed. E- (4 ) that atmospheric CO2 plays a critical role apparent fine control over periods of many mail: falko@imcs.rutgers.edu in regulating Earth’s temperature (5, 6 ). thousands of years around those limits, sug- ‡Members of the IGBP Working Group. Analyses of ice cores strongly suggest that gest strong feedbacks that constrain the sink www.sciencemag.org SCIENCE VOL 290 13 OCTOBER 2000 291 12 #cyclesofcirculation Downloaded from www.sciencemag.org on November 26, 2012 S C I E N C E ’ S C O M P A S S strengths in both the oceans and terrestrial ganic carbon in the ocean increases markedly thereby reducing the rate of oceanic uptake of ecosystems. The relatively rapid transition below about the upper 300 m, where it remains anthropogenic CO2. The magnitude of these from glacial to interglacial states and the significantly above the surface ocean-atmo- feedbacks is critically dependent on how initially steep, but eventually gradual, transi- sphere equilibrium value in all ocean basins. ocean circulation and mixing will respond to tion into glacial periods (8) suggests that the The higher concentration of inorganic carbon in the climatic forcing. rates of absorption and emission of CO2 from the ocean interior results from a combination of Biological processes also contribute to the the oceans and terrestrial ecosystems are two fundamental processes: the “solubility absorption of atmospheric CO2 in the ocean. asymmetrical. It should be noted that because pump” and “biological pumps” (14, 15). Phytoplankton photosynthesis lowers the par- of this asymmetry, the average atmospheric The efficiency of the solubility pump de- tial pressure of CO2 in the upper ocean and CO2 concentration during the past 420,000 pends on the thermohaline circulation and on thereby promotes the absorption of CO2 from years was only !220 ppmv, not 280 ppmv as latitudinal and seasonal changes in ocean the atmosphere. Approximately 25% of the usually ascribed (12). ventilation (16, 17 ). CO2 is more soluble in carbon fixed in the upper ocean sinks into the How is atmospheric CO2 regulated? The cold, saline waters, and sequestration of at- interior (21, 22), where it is oxidized through total of dissolved inorganic carbon in the mospheric CO2 in the ocean interior is there- heterotrophic respiration, raising the concen- oceans is 50 times that of the atmosphere fore controlled by the formation of cold, tration of dissolved inorganic carbon (DIC). (Table 1), and on time scales of millennia, dense water masses at high latitudes, espe- The export of organic carbon from the sur- the oceans determine atmospheric CO2 con- cially in the North Atlantic and in the South- face to the ocean interior presently accounts centrations, not vice versa. Atmospheric CO2 ern Ocean confluence. As these water masses for !11 to 16 Gt of carbon per year (23). This continuously exchanges with oceanic CO2 at sink into the ocean interior and are transport- process keeps atmospheric CO2 concentra- the surface. This exchange, which amounts to ed laterally, CO2 is effectively prevented tions 150 to 200 ppmv lower than they would !90 gigatons (Gt) of carbon per year in each from re-equilibrating with the atmosphere by be if all the phytoplankton in the ocean were direction, leads to rapid equilibration of the a cap of lighter overlying waters. Re-equili- to die (23, 24 ). In addition to the organic atmosphere with the surface water. Upon dis- bration occurs only when waters from the biological pump, several phytoplankton and solution in water, CO2 forms a weak acid that ocean interior are brought back to the surface, zooplankton species form CaCO3 shells that reacts with carbonate anions and water to decades to several hundreds of years later. sink into the interior of the ocean, where form bicarbonate. The capacity of the oceanic Coupled climate-ocean simulations (6, some fraction dissolves. This inorganic car- carbonate system to buffer changes in CO2 18) suggest that CO2-induced global warm- bon cycle leads to a reduction in surface concentration is finite and depends on the ing will lead to increased stratification of the ocean DIC relative to the deep ocean and is addition of cations from the relatively slow water column. If this occurs, the transport of therefore sometimes called the “carbonate weathering of rocks. Because the rate of an- carbon from the upper ocean to the deep pump.” The process of precipitating carbon- thropogenic CO2 emissions is several orders ocean will be reduced, with a resulting de- ates, however, increases the partial pressure of magnitude greater than the supply of min- crease in the rate of sequestration of anthro- of CO2 (25). Hence, on time scales of centu- eral cations, on time scales of millennia the pogenic carbon in the ocean (19, 20). The ries, while the carbonate pump lowers DIC ability of the surface oceans to absorb CO2 combined effects of progressive saturation of concentrations in the upper ocean, it simulta- will inevitably decrease as the atmospheric the buffering capacity and increased stratifi- neously leads to the evasion of CO2 from the concentration of the gas increases (13). cation will weaken two important negative ocean to the atmosphere. The concentration of total dissolved inor- feedbacks in the carbon-climate system, Coupled climate-biogeochemical models suggest that the biological pumps tend to counteract the decrease in uptake caused by the solubility pump (20, 26 ). If the biological pumps are to absorb anthropogenic CO2 in the coming century, their efficiency must in- crease. In principle, this can be accomplished by any or all of four processes: (i) enhancing utilization of excess nutrients in the upper ocean, (ii) adding one or more nutrients that limit primary production, (iii) changing the elemental ratios of the organic matter in the ocean, and (iv) increasing the organic carbon/ calcite ratio in the sinking flux (27 ). There are significant gaps in our knowledge that limit our ability to predict the magnitude of changes in oceanic uptake, but the likely changes in the biological pump are too small to counteract the projected CO2 emissions in the coming century. Almost certainly, how- ever, changes in oceanic ecosystem structure will accompany changes in physical circula- tion (and hence changes in nutrient supplies), lowered pH, and changes in the hydrological cycle. Our present knowledge of the factors that determine the abundance and distribution Fig. 1. A correlation between atmospheric partial pressure of CO (pCO ) and isotopic (" ) of key groups of marine organisms is so2 2 D temperature anomalies as recorded in the Vostok ice core. The figure shows that climate variations limited that it is unlikely we will be able to in the past 420,000 years operated within a relatively constrained domain. Data are from (8). predict such changes within the next decade 292 13 OCTOBER 2000 VOL 290 SCIENCE www.sciencemag.org 13 #cyclesofcirculation Downloaded from www.sciencemag.org on November 26, 2012 S C I E N C E ’ S C O M P A S S with reasonable certainty (28). These uncer- counteract and even exceed the enhancement to about 5% of the present anthropogenic tainties affect our ability to predict specific of NPP (41). The combined effects of higher CO emissions. 2 responses, but not the sign of the changes in CO2 concentrations, higher temperatures, and There is no evidence that phosphorus sig- atmospheric CO2 or the impact of this change changes in disturbance and soil moisture re- nificantly limits primary production in coast- on upper ocean pH. If our current understand- gimes lead to considerable uncertainty about al or open oceans on a global scale (51) or ing of the ocean carbon cycle is borne out, the the ability of terrestrial ecosystems to miti- that phosphorus loading of the coastal oceans sink strength of the oceans will weaken, leav- gate against rising CO2 in the coming decades has significantly altered global primary pro- ing a larger fraction of anthropogenically pro- (42). However, recent results from long-term duction (46). duced CO2 in the atmosphere or to be ab- soil warming experiments in a boreal forest Iron is a micronutrient that limits both sorbed by terrestrial ecosystems. contradict the idea that the projected rise in primary production (52) and nitrogen fixation Terrestrial ecosystems also exchange CO2 temperature is likely to lead to forests that are in many areas of the ocean (53). Eolian rapidly with the atmosphere, but unlike in the now carbon sinks becoming carbon sources (windborne) iron fluxes, a principal source of oceans, there is no physicochemical pump. in the foreseeable future (43). iron input to the open ocean, are coupled both CO2 is removed from the atmosphere through Again, as in the case of marine ecosys- to land use and the hydrological cycle (54). photosynthesis and stored in organic matter. tems, we can predict that the negative feed- Episodic aridity affects eolian iron supplies, It is returned to the atmosphere via a number back afforded by terrestrial ecosystems in and in the coming decades, iron fluxes to the of respiratory pathways that operate on vari- removing anthropogenic CO2 from atmo- ocean could therefore increase because of ous time scales: (i) autotrophic respiration by sphere will continue; however, the sink increased evaporation of soil moisture or de- the plants themselves; (ii) heterotrophic res- strength will almost certainly weaken. The crease because of increased precipitation piration, in which plant-derived organic mat- exact magnitude of the change in sink (55). Increases in evaporation and increases ter is oxidized primarily by soil microbes; strength remains unclear. in precipitation are expected in different parts and (iii) disturbances, such as fire, in which Interaction of the carbon cycle with other of the land surface in response to increasing large amounts of organic matter are oxidized biogeochemical cycles. All biotic sinks for global temperatures. Thus, although increas- in very short periods of time. CO2 require other nutrients in addition to ing temperature and its potential influence on On a global basis, terrestrial carbon stor- carbon. Humans have affected virtually every the availability of iron in the open ocean will age primarily occurs in forests (29). The sum major biogeochemical cycle (Table 2), but affect the biological uptake of carbon in the of carbon in living terrestrial biomass and the effects of these impacts on the interac- ocean, at present we do not know the sign of soils is approximately three times greater tions between these elemental cycles are the changes. However, even if iron fluxes than the CO2 in the atmosphere (Table 1), but poorly understood (44). The production of were to increase to such an extent that oce- the turnover time of terrestrial carbon is on synthetic fertilizers, the cultivation of nitro- anic nitrogen fixation were stimulated to the the order of decades. Direct determination of gen-fixing crops, and the deposition of fossil maximum, the maximum change in atmo- changes in terrestrial carbon storage has fuel–associated nitrogen are collectively of spheric CO2 that could ensue would be about proven extremely difficult (30). Rather, the the same order of magnitude as natural bio- 40 ppmv. Although not insignificant, such an contribution of terrestrial ecosystems to car- logical nitrogen fixation (45). These inputs effect is unrealistic on time scales of centu- bon storage is inferred from changes in the will continue to rise with the projected in- ries (56). concentrations of atmospheric gases, espe- crease in human population (46). Similarly, Eolian nitrogen inputs can also potentially cially CO2 and O2, their isotopic composi- there has been an approximately fourfold in- enhance both terrestrial and marine uptake of tion, inventories of land use change, and crease in phosphorus inputs to the biosphere, anthropogenic CO2 (37 ). In terrestrial eco- models (31–33). The models require accurate primarily due to mining of phosphorus com- systems, the sink strength resulting from eo- knowledge of the oceanic uptake of CO2 (31, pounds for fertilizer. lian nitrogen deposition depends on the car- 34, 35). At first glance, one might conclude that bon: nitrogen ratio of the stored organic mat- Terrestrial net primary production (NPP) simultaneous increases in nitrogen fixation (36 ) is not saturated by present atmospheric and phosphate production would stimulate Table 1. Carbon pools in the major reservoirs on CO2 concentrations (37 ). Consequently, as the biological sequestration of carbon in ter- Earth. atmospheric CO2 increases, terrestrial plants restrial and marine ecosystems. Will such are a potential sink for anthropogenic carbon. stimulation provide salvation from the con- Pools Quantity The principal carbon-fixing enzyme in plants tinued anthropogenic emissions of CO (Gt)2 to the is ribulose 1,5-bisphosphate carboxylase/ox- atmosphere? Atmosphere 720 ygenase (rubisco) (38). In C3 plants, the ac- It is estimated that by 2050, the total tivity of rubisco increases with increasing transport of fixed inorganic nitrogen from Oceans 38,400Total inorganic 37,400 CO2 concentrations, saturating between 800 land to the coastal zone will have increased Surface layer 670 and 1000 ppmv CO2, a concentration that from the present value of !20 teragrams (Tg) Deep layer 36,730 will probably be reached early in the next of nitrogen to ! 40 Tg of nitrogen per year Total organic 1,000 century at the present emissions rate (2). Be- (47 ), concomitant with an increase in human Lithosphere cause the saturation function decreases as population from 6 to 9 or 10 billion. Al- Sedimentary carbonates "60,000,000 CO2 increases, terrestrial plants will become though nutrient loading has resulted in coast- Kerogens 15,000,000 less of a sink for CO2 in coming decades. al eutrophication on a global scale (48), deni- Terrestrial biosphere (total) 2,000 Some experimental evidence suggests that trification presently removes virtually all Living biomass 600–1,000 because of nutrient limitation (39), NPP may land-derived nitrogen before it can reach the Dead biomass 1,200 level off at only 10 to 20% above current open ocean (49, 50). Coastal denitrification Aquatic biosphere 1–2 rates, at an atmospheric CO2 concentration of thus effectively decouples the terrestrial and Fossil fuels 4,130 550 to 650 ppmv, or double preindustrial oceanic nitrogen cycles. However, even if no Coal 3,510 concentrations (40). Furthermore, increased denitrification occurred, the increased flux of Oil 230 temperature will probably lead to higher mi- land-derived nitrogen would sequester only Gas 140Other (peat) 250 crobial heterotrophic respiration, which may 0.4 Gt of carbon per year (48), corresponding www.sciencemag.org SCIENCE VOL 290 13 OCTOBER 2000 293 14 #cyclesofcirculation Downloaded from www.sciencemag.org on November 26, 2012 S C I E N C E ’ S C O M P A S S ter and the degree of nitrogen saturation of and where soils are mostly limited by phos- while simultaneously reducing the land area soils (44, 57–59). Nitrogen deposition is pre- phate (57). In the context of the global carbon available for active sinks. Abandonment of dicted to continue and has the potential to cycle, the eolian input of nitrogen to marine agricultural land and regrowth of forests, enhance the carbon sink in nitrogen-limited ecosystems is essentially irrelevant (59). largely in the temperate Northern Hemi- ecosystems, but it will probably become de- In addition to ecophysiological consider- sphere, may be a significant terrestrial CO2 creasingly effective at doing so. Future nitro- ations, land use change plays a major role in sink at present (34) but cannot be sustained gen deposition will largely occur on already the carbon source/sink dynamics. The in- indefinitely. This sink can buy some time, but nitrogen-saturated soils, such as in the forests creased pressure in the developing world to unless CO2 emissions are reduced, it cannot of Western Europe, China, and India, and on increase food and fiber production by con- mitigate against continued accumulation of agricultural lands in the tropics, whose capac- verting forests to agricultural use effectively the gas in Earth’s atmosphere given projected ity to sequester carbon is intrinsically small increases the flux of carbon to the atmosphere emission scenarios. The Need for an Integrated Systems Table 2. Examples of human intervention in the global biogeochemical cycles of carbon, nitrogen, Approach phosphorus, sulfur, water, and sediments. Data are for the mid-1900s. The global carbon cycle is affected by human activities and is coupled to other climatolog- Magnitude of flux (millions of metric tons per year) % change due to ical and biogeochemical processes. As dis-Element Flux human activities cussed above, we have considerable informa- Natural Anthropogenic tion about specific aspects of the carbon cy- cle, but many of the couplings and feedbacks C Terrestrial respiration and decay CO2 61,000 are poorly understood. As we drift further Fossil fuel and land use CO2 8,000 !13 away from the domain that characterized the N Natural biological fixation 130 preindustrial Earth system, we severely test Fixation owing to rice cultivation, 140 !108 the limits of our understanding of how the combustion of fossil fuels, and production of fertilizer Earth system will respond. A look at the current understanding of P Chemical weathering 3 glacial-interglacial CO2 changes illustratesMining 12 !400 the problem. Perhaps surprisingly, there is no S Natural emissions to atmosphere at 80 consensus on the causes of these changes. Earth’s surface There are at least 11 hypotheses (53, 60, 61), Fossil fuel and biomass burning 90 !113 emissions which may be grouped into three basic themes: (i) physical/chemical “reorganiza- O and H Precipitation over land 111 " 1012 (as H2O) Global water usage 18 10 12 16 tion” of the oceans, (ii) changes in the ocean" ! carbonate system, and (iii) changes in ocean Sediments Long-term preindustrial river 1 " 1010 nutrient inventories. Many of these hypothe- suspended load Modern river suspended load 2 " 1010 !200 ses are not mutually exclusive. The interac- tions between marine and terrestrial ecosys- tems, changes in ocean circulation, radiative forcing, and greenhouse gases all probably interact in a specific sequence to give rise to the natural cyclic atmospheric and climatic oscillations. These interactions are not pres- ently represented in detailed models of the glacial-interglacial transitions. This example illustrates three points. First, in the recent history of Earth, the car- bon cycle did not operate in a vacuum and was not constrained to a specific reservoir. Natural changes in the inventories of carbon, as inferred from the ice core records of gla- cial-interglacial transitions, are linked to oth- er biogeochemical and climatological pro- cesses. Those linkages continue to the present, but the quantitative impacts in the coming century are obscured by simultaneous alterations of numerous biogeochemical cy- cles through human activities. Second, the scientific community has generally ap- proached problems such as glacial-intergla- cial transitions from a disciplinary perspec- tive. This approach has not produced com- Fig. 2. Schematic variance spectrum for CO2 over the course of Earth’s history. Note the impact of human perturbations on the decade-to-century scale. (Inset) Changes in atmospheric CO over the pletely satisfactory explanations for what is2 past 420,000 years as recorded in the Vostok ice, showing that both the rapid rate of change and clearly a large natural perturbation in the the increase in CO2 concentration since the Industrial Revolution are unprecedented in recent global carbon cycle. Because of the disciplin- geological history. ary nature of research, interactions between 294 13 OCTOBER 2000 VOL 290 SCIENCE www.sciencemag.org 15 #cyclesofcirculation Downloaded from www.sciencemag.org on November 26, 2012 S C I E N C E ’ S C O M P A S S components of the Earth system are not in- References and Notes 19. J. L. Sarmiento, T. M. C. Hughes, R. J. Stouffer, S. corporated into present biogeochemical or 1. M. I. Hoffert et al., Nature 395, 881 (1998). Manabe, Nature 393, 245 (1998). climate models. When changes in isolated 2. J. T. Houghton, G. J. Jenkins, J. J. Ephraums, Eds., 20. F. Joos, G.-K. Plattner, T. Stocker, O. Marchal, A. processes are considered, we usually under- Climate Change: The IPCC Scientific Assessment Schmittner, Science 284, 464 (1999). (Cambridge Univ. Press, Cambridge, 1996). 21. P. G. Falkowski, R. T. Backer, V. Smetacek, Science stand the signs of feedbacks, if not the mag- 3. The International Geosphere-Biosphere Programme 281, 200 (1998). (IGBP) is an umbrella organization that coordinates 22. E. Laws, P. Falkowski, W. O. Smith, H. Ducklow, J.nitudes of the responses. It is when processes (but does not fund) large multinational research pro- McCarthy, Global Biogeochem Cycles, in press.interact that we have significant problems in grams. Several of these programs have focused on 23. This is the apparent steady-state value, not the reproducing the phenomena quantitatively. the carbon cycle in specific reservoirs: The flagship change in the net exchange with the atmosphere. Clearly, a systems approach is needed. Third, program for terrestrial ecosystems is Global Change 24. This so-called “Strangelove” ocean scenario is uncer- reconstructions of the carbon cycle (for ex- and Terrestrial Ecosystems (GCTE); for the oceans, it tain within about a factor of 2 because we do not is the Joint Global Ocean Flux Study ( JGOFS); for the have better estimates of export fluxes of carbon in ample, during glacial-interglacial transitions) atmosphere, it is International Global Atmospheric the oceans (22). provide testable hypotheses about the Earth Chemistry (IGAC); and for paleochemistry and paleo- 25. This (perhaps counterintuitive) effect is a direct out-come of the calcification reaction, which can be sum- system. Consensus on how a 100-ppmv climate, it is Past Global Changes (PAGES). 4. S. Arrhenius, marized as 2HCO ! Ca7 CaCO ! CO ! H O. ThePhilos. Mag. J. Sci. (London, Edinburgh, 3 3 2 2 change in atmospheric CO can occur natu- , 237 (1896). mean residence time of Ca in the oceans is 8.5 # 10 5 2 Dublin) 41 2! rally within a 100,000-year time frame (62) years (it is even longer for Mg ). On time scales of5. M. I. Budyko, The Earth’s Climate: Past and Future millions of years, as the Ca supply from weathering would imply some understanding of the feed- (Academic Press, New York, 1982). keeps pace with the precipitation of carbonates, car- backs within the Earth system. Knowledge of 6. J. F. B. Mitchell, T. C. Johns, J. M. Gregory, S. F. B. Tett, bonate formation and burial become significant sinks Science 376, 501 (1995). these feedbacks does not give us predictive for CO2. In fact, carbonates are the largest reservoir of7. H. J. Smith, H. Fischer, M. Wahlen, D. Mastroianni, B. carbon on Earth ( Table 1). As CO dissolves in seawater, capability for the coming decades or centu- Deck, Nature 400, 248 (1999). 2it forms carbonic acid, which lowers pH (13). Thus, as ries, but it can help us develop the modeling 8. J. R. Petit et al., Nature 399, 429 (1999). atmospheric CO2 increases, the pH of the upper ocean tools needed to integrate the detailed infor- 9. The reconstruction of paleotemperatures from the decreases until the buffering capacity of the ocean isice cores is based on the H/D and 18/16O fraction- restored by the dissolution of carbonates. mation gathered from component studies of ation in the precipitation. Necessarily, the inferred 26. J. L. Sarmiento, T. M. C. Hughes, R. J. Stouffer, S. the contemporary world. temperature is that of the upper troposphere, not Manabe, Nature 393, 245 (1998). Our analysis above shows that although that at ground level. Moreover, the inferred temper- 27. J. L. Sarmiento and U. Siegenthaler, Primary Produc-ature is not a global mean but rather a value for the natural sinks can potentially slow the rate of tivity and Biogeochemical Cycles in the Sea, P. G.region, in this case, Vostok in Antarctica. Despite Falkowski, Ed. (Plenum, New York, 1992), pp. 316– increase in atmospheric CO2, there is no nat- these caveats, the glacial-interglacial temperature 317. ural savior waiting to assimilate all the an- trends and anomalies are highly consistent on time 28. Following up on the work of the JGOFS program, the scales of 100,000 years for the four cycles obtained thropogenic CO responses of marine ecosystems to changes in cli-2 in the coming century. Al- from the ice core. mate and CO in the coming century have been though on geological time scales the anthro- 210. T. Crowley, Science 289, 270 (2000). identified by biological oceanographers as a key re- pogenic emission of CO is a transient phe- 11. On time scales of millions of years, vulcanism and search topic for the next decade in funding agency2 nomenon (Fig. 2), it will affect Earth’s weathering reactions are critical determinants of at- planning.mospheric CO2. The weathering reactions can be 29. The storage of carbon in terrestrial ecosystems isbiogeochemical cycles for hundreds of years summarized by the following: primarily related to the relative resistance of lignin to come (20, 63). Our present imperfect mod- weathering and other polymeric carbon complexes to degrada- els suggest that the feedbacks between carbon CO ! CaSiO % CaCO ! SiO tion or herbivory. Terrestrial plants contain, on aver-2 3 3 2 age, substantially more organic carbon per unit of and other biogeochemical and climatological metamorphosis nitrogen or phosphorus than their marine counter- processes will lead to weakened sink parts, the phytoplankton, which are primarily com- strengths in the foreseeable future, and the where Mg can substitute for Ca. CO2 is resupplied to posed of protein. Although lignins and other carbon-the atmosphere by vulcanism [ J. F. Kasting, O. B. prospects of retrieving anthropogenic CO rich polymers may accumulate in terrestrial ecosys-2 Toon, J. B. Pollack, Sci. Am. 258, 90 (1988)]. On time tems on time scales of decades, on longer time scales from the atmosphere by enhancing natural scales of decades, these processes are relatively in- most of these molecules are oxidized, so that the sinks are small. This condition cannot persist significant in determining atmospheric CO2 as com- accumulation of organic carbon in soils is a minisculepared with the exchanges of CO between oceanic indefinitely. Potential remediation strategies, 2 fraction of the total carbon fixed by the ecosystem.and terrestrial ecosystems. Lakes may also store substantial amounts of organic such as the purposeful manipulation of bio- 12. The preindustrial concentration of CO2 was "280 matter in sediments [W. E. Dean and E. Gorham, logical and chemical processes to accelerate ppmv throughout the Holocene. The lower mean Geology 26, 535 (1998)]. value is due to the fact that the glacial periods (with the sequestration of atmospheric CO2, are 30. R. Myneni, C. Keeling, C. Tucker, G. Asrar, R. Nemani, low CO2 concentrations) were about four times long- Nature 386, 698 (1997). being seriously considered by both govern- er than the interglacial periods. In fact, most of the 31. P. P. Tans, I. Y. Fung, T. Takahashi, Science 247, 1431 mental bodies and private enterprises. These recent history of Earth is dominated by a glacial (1990). climate, with relatively short punctuations of inter- mitigation strategies will themselves have un- 32. R. F. Keeling and S. R. Shertz, Nature 358, 723 (1992).glacial phases. If the low CO2 levels of glacial periods 33. M. Battle et al., Science 287, 2467 (2000). known consequences and must be carefully had persisted through the Holocene, plants that pro- 34. S. Fan et al., Science 282, 442 (1998). assessed within the context of an integrated vided food and fiber for early human civilization may 35. An invaluable further constraint on both oceanic and not have been cultivatable [R. F. Sage, Global Change systems approach before any action is taken. terrestrial carbon uptake is provided by followingBiology 1, 93 (1995)]. annual and interannual changes in atmospheric O As we rapidly enter a new Earth system 13. Given projected rates of increase in atmospheric CO , 22 concentrations. With this approach, it is assumed domain, the “Anthropocene” Era (64), the the pH of the surface waters will decrease by "0.2 that intraannual decreases in O2 and increases in CO2 debate about distinguishing human effects units within this century. This decrease will signifi- are due to the combined effects of fossil fuel burningcantly hinder the biological precipitation of calcium from natural variability will inevitably abate and deforestation. Increases in O2 with decreasedcarbonates [ J. Klyepas et al., Science 284, 118 CO2 are a consequence of terrestrial uptake, and in the face of increased understanding of (1999); C. Langdon et al., Global Geochem. Cycles 14, decreases in CO2 with minimal changes in O2 repre- climate and biogeochemical cycles. Our 639 (2000)]. sent oceanic uptake of the former gas. 14. T. Volk and M. I. Hoffert, in The Carbon Cycle and present state of uncertainty arises largely 36. NPP is the difference between gross primary produc-Atmospheric CO2: Natural Variations Archean to tion and plant respiration. from lack of integration of information. Nev- Present, E. T. Sunquist and W. S. Broeker, Eds. (Amer- 37. D. S. Schimel, Global Change Biol. 1, 77 (1995). ertheless, scientists’ abilities to predict the ican Geophysical Union, Washington, DC, 1985), pp. 38. S. P. Long and B. G. Drake, Crop Photosynthesis: 99–110. future will always have a component of un- Spatial and Temporal Determinants, N. R. 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These levels of CO2 can be North Atlantic [ J. Wu, W. Sunda, E. Boyle, D. Kari, 62. The transition into glacial periods is gradual, with reached within the next 50 years. Science 298, 759 (2000)]. several phases, and occurs over several tens of thou- 41. M. U. F. Kirschbaum, Soil Biol. Biochem. 27, 753 (1995). 52. K. Coale et al. Nature 383, 495 (1996). sands of years, whereas the transition to an intergla- 42. F. A. Bazzaz, Annu. Rev. Ecol. Syst. 21, 167 (1990). 53. P. Falkowski, Nature 387, 272 (1997). cial state occurs within 10,000 years. 43. P. Jarvis and S. Linder, Nature 405, 904 (2000). 54. I. Fung et al., Global Biogeochem. Cycles 14, 281 63. J. Sarmiento and C. Le Quere, Science 274, 1346 44. P. Vitousek, H. Mooney, J. Lubchenco, J. Melillo, Sci- (2000). (1996). ence 277, 494 (1997). 55. A. Dai, I. Fung, A. Del Genio, J. Clim. 10, 2943 (1997). 64. P. Crutzen and E. Stoermer, IGBP Newsl. 41, 17 45. J. N. Galloway, W. H. Schlesinger, H. Levy, A. 56. The change in nitrogen inventories in the ocean may (2000). Michaels, J. L. Schnoor, Global Biogeochem. Cycles 9, makes a substantial contribution to the drawdown of 235 (1995). 65. This article is based on a workshop on the globalCO2 on glacial-interglacial time scales (53, 60). 46. R. Howarth, Ed., Nitrogen Cycling in the North Atlan- 57. S. Hall and P. Matson, Nature 400, 152 (1999). carbon cycle held at the Royal Swedish Academy of tic Ocean and Its Watersheds (Kluwer Academic, Bos- 58. K. J. Nadelhoffer et al., Nature 398, 145 (1999). Science in November 1999. The workshop was orga- ton, 1996). 59. The estimated annual global eolian flux of fixed nized by the International Biosphere-Geosphere Pro- 47. C. Kroeze and S. Seitzinger, Nutr. Cycl. Agroecosyst. inorganic nitrogen (NO ) to the ocean is 12.3 Tg, of gramme (IBGP) and the Royal Swedish Academy ofy 52, 195 (1998). which 9 Tg is from anthropogenic sources (45). As- Science, in collaboration with Stockholm University 48. J. J. Walsh, Nature 350, 53 (1991). suming that all that nitrogen was used to fix CO , the and the Swedish University of Agricultural Sciences.2 49. J. P. Christensen, J. W. Murray, A. H. Devol, L. A. net stimulation amounts to !65 Tg of carbon per Financial support was provided by the Swedish Mil- Codispoti, Global Biogeochem. Cycles 1, 97 (1987). year. This is less than 1% of the global annual an- lennium Committee and by MISTRA (the Swedish 50. S. P. Seitzinger and A. E. Giblin, Biogeochemistry 35, thropogenic emission of CO2. Foundation for Strategic Environmental Research). 235 (1996). 60. W. S. Broecker and G. M. Henderson, Paleoceanogra- The workshop was the first of five Stockholm work- 51. There are exceptions of course. Phosphorus limitation phy 13, 352 (1998). shops contributing to the IGBP synthesis project. occurs in the Mediterranean and parts of the western 61. R. Keeling and B. Stephens, Nature 404, 171 (2000). Thanks to J. Raven for comments. 296 13 OCTOBER 2000 VOL 290 SCIENCE www.sciencemag.org 17 #cyclesofcirculation Downloaded from www.sciencemag.org on November 26, 2012 Harney, S. M. & Moten, F. (2017). Base faith. E-Flux Journal, (86), 1. A poetic, research based essay on processes and systems of the earth, in relationship to futures on the planet, pasts and futures of ownership and capital. “What’s at stake is the trace of perfume that has been released.” 18 #cyclesofcirculation The earth moves against the world. And today the response of the world is clear. The world answers in fire and flood. The more the earth churns the more vicious the world’s response. But the earth still moves. Tonika Sealy Thompson might call it a procession. The earth’s procession is not on the world’s calendar. It is not a parade on a parade ground. It is not in the world’s teleology. Nor is the procession exactly a carnival played to mock or overturn this parade, to take over its grounds. A procession moves unmoved by the world. The earth’s procession around which all processions move struts in the blackness of time. And the earthen who move around, and move in earth’s procession, move, as Stefano Harney and Fred Moten Thompson says, like Sisters of the Good Death in Base Faith Bahia move, in their own time out of time. God isso powerful in this procession that he cannot exist. Not because he is everywhere in the procession but because we are. We are the moving, blackened, blackening earth. We turn each other over, dig each other up, float each other off, sink down with each other and fall for each other. We move in earthen procession swaying to base even as its beat alerts the world’s first responders. These responders are called strategists. Strategy responds to the constant eruption of the earth into and out of the world. The response takes the form of a concept upon which form has been imposed, which is then imposed upon the earthen informality of life. Some say it was Alfred Sohn-Rethel who first figured out how the concept was, in this interplay of formation and enforcement, stolen into ownership, abducted and abstracted, weaponized in strategy. He said the abstraction of exchange, and later the abstraction of money, led us to think in the suspension of time and space, the suspension of materiality, and this led to the propriation of the concept. But Sohn- Rethel only picks up the trail of this theft with the thief, the individual, already formed and ready for the strategized and immaterial concept, already formed and readied by it. He wants to convict this thief. We want to take him home. We want to take him out ‘cause out is home. We’re at home in the prophetic churning of the earth on the move, the round run of the fugitive, visitation in our eyes, refuge on our tongues. Our unholy commune with those who keep moving and stay there, who keep out before they can be kept out. That’s why the hellhounds of strategy are on our trail. They think they got the scent of our leader. But our leader is not one. Let’s call her Ali, after Pasolini’s “Profezia.” Ali Blues Eyes. Pasolini thought she was coming in the procession from Africa to teach Paris how to love, to teach London brotherhood, to march east with 11.08.17 / 13:32:05 EST 19 #cyclesofcirculation e-flux journal #86 — november 2017 Stefano Harney and Fred Moten 01/07 Base Faith A smiley face appears in a Hawaiian volcano's crater during an eruption during 2016. 11.08.17 / 13:32:05 EST 20 #cyclesofcirculation 02/07 the red banners of Trotsky in the wind. But she capital. The world’s only argument against the never arrived because we went to chant in earth is logistical. It must be done. The earth’s Palermo, fast in Alabama, meditate in Oaxaca. So movement must be stopped, or contained, or Ali became Tan Malaka and we went to the fête, weakened, or accessed. The earthen must the jam, the study group. become clear and transparent, responsible and *** productive, unified in separation. This is not a Ever since capital witnessed Lenin doing it matter of deploying the concept, strategically or better, capital has been running from strategy. otherwise, but of force, forced compliance, Today when capital deploys a concept, everybody forced communication, forced convertibility, is supposed to buy it but no one is supposed to forced translation, forced access. Capital does believe it. Capital might call this strategic not argue, though many argue with it. universality. Or it might not call it anything Capital just likes disruption. Capital’s been because capital is not concerned with the dignity running from strategy, running toward logistics, or the sovereignty of the concept. The concept running as logistics, running into the arms of the served its purpose. And its main purpose now is algorithm, its false lover who is true to it. All to get out of the way of logistics or to become that’s left of strategy is leadership, the command logistics’ conduit. Its propriety and its you find yourself in after logistics takes over, proprietary commitments prepare it to be bought when the unit comes into its own. For capital, and sold into a roughened, airy thinness. Today’s strategy is a just a form of nostalgia, or proof concepts in circulation are not the abstraction of that it has nothing to fear from its enemies who or from the commodity; they are commodities embrace it, proof that they are not enemies. They and cannot, in their propriety and proprietary are the commanded, repeating commands. They form, be used against the commodity-form. Their call it policy. Ali was never in command. She’s form is the air the commodity expels, just made up of the hungry. She’s just made up of containerized, as all but impalpable units of plans. exhaust(ion). They are just another strategy. And In his desire to make capital claim its strategy, though it is not abstract, does not really materiality Marx took Ali’s. Tried to make her a matter, either. What matters is logistics. leader. But Ali’s prophesy was too crowded, too Logistics, not strategy, provides the imperative. black, too late, too loud. Submerged in capital, Strategy just provides the friction. Logistics the earthen buried strategy and detonated it. The moves the concept around in the circuits of first respondents told us we need to learn to be Filmstill from Pier Paolo Pasolini's 1967 movie Oedipus Rex. 11.08.17 / 13:32:05 EST 21 #cyclesofcirculation 03/07 Cover art for Ornette Coleman’s third studio album The Shape of Jazz to Come (1959). 11.08.17 / 13:32:05 EST 22 #cyclesofcirculation 04/07 more strategic. We will learn to need strategy, canted blackness (where flesh and earth they say. But we know strategy is the delivery converge beyond the planetary, in and as non- system for a concept, collateral and deployed. particulate differentiation). It’s not about a Indeed, strategy is itself just a concept in the return to some preconceptual authenticity so world, the universal approach. But not even much as matter’s constant aeration, its constant capital cares. Capital only wants things to run turning over, its exhaustion and exhaustive smoothly, which is to say universally. This is what sounding, its ascentual and essentially and disruption is for, and leadership, and open existentially sensual descent. The problem is the innovation. Capital does not fear strategy. It can separation of the concept and our subsequent barely remember it from the days of worldly envelopment within it – this horrific sovereignty concepts. Marx made capital a concept. Lenin of the concept and its variously hegemonic saw his chance. So capital learned to be material representations. Did the invention of sovereignty again. No, capital doesn’t fear strategy. Capital require the concept or did the concept already fears the earth’s procession. Ali’s blues black bear the danger of sovereignty’s brutal saint eyes. representation(s)? *** Maybe the problem is the separability, the God has everything but faith; this is why He self-imposed loneliness-in-sovereignty, of the so brutally requires ours. He looked around and concept and its representations (as embodiment was so lonely He made Him a world. Rightly, He or individuation or subject or self or nation or didn’t believe in himself and, wrongly, He didn’t state). How do we make sure that the concept believe in us. We were neither sempiternal nor still matters? How do we refuse its parental, just generative and present, like a dematerialization, even if/when that wave. In His case, (over)seeing was not believing. dematerialization seems to have allowed the Faithlessness such as His demands a certain production of new knowledge, of new critical strategic initiative. Ever get the feeling we’re resources? This is a question that is explicitly for being watched? Well, that’s just God’s property, Marx. When the senses become theoreticians in the police, the ones who proclaim and carry out their practice, in communism, which is here, His strategic essentialism. They have some guns buried alive, they ask questions of the one who that look just like microphones. Sometimes they brilliantly, and for us, both charts and re- write books. They tell us what we need. Often, instantiates the dematerialization that capital they are us. We’re all but them right now but pursues in the separation of labor power from we’re gonna try to fade back in and out as quickly the flesh of the worker or of profit from that flesh as possible. Mattafack, let’s sound it out, let’s in its irreducible entanglement with (the matter talk it over. If you could start talking over us right of) earth. Was that an instance of “strategic now we’d appreciate it. thinking”? If so, it demands that we rethink Unremitting predication – what if this is our strategy. Is there a way to think the relation existence, given in and as a practice of chant, a between strategy and improvisation that alloys ceaseless and ceaselessly inventive liturgy? You the maintenance of a difference between could call it the historicization of a veridical immediacy and spontaneity? There is a protocol in which the distinction between falsity deliberate speed of improvisation that is not and transformation, untruth and unchecked simply recourse to the preconceptual. Maybe differentiation, is kept sacred. And it’s not even what’s at stake is the difference between vulgarly temporal in the way that seeing aspects, movement and a movement or the movement. as Wittgenstein describes it, implies a timeline – What’s at stake is the trace of perfume that first it was a duck and then it was a rabbit. There has been released. It is changed in being- is, in the simultaneity of “it is a duck” and “it is a sensual, depurified in being breathed. There is a rabbit,” a kind of music. Ornette Coleman calls it socialization of essence that is given in and as “harmonic unison” and we might follow him while sociality itself and maybe this is what Marx was also deviating from him but in and through him talking about under the rubric of sensuous by calling it anharmonic unison, a differential activity, but against the grain of his adherence to inseparability. When essence leaves existence by a logic and metaphysics of (individuation in) the wayside, what ensues, for essence, is relation. All this makes you wonder what the existential loneliness. What if the problem of the difference is between strategy and faith. When concept is the problem of separation? And what we say difference, here, what we really mean is is the relationship between conceptual caress – how strategy and faith rub up against separation and individuation? What’s at stake is one another in a kind of haptic eclipse, or the convergence of the body and the concept auditory submergence, or olfactory disruption, or that is given in the transcendental aesthetic. gustatory swooning of the overview. In this Individuation and completeness follow. On the regard, strategic essentialism is something like other hand, (en)chanted, (en)chanting matter, the soul feast’s homiletic share or, more 11.08.17 / 13:32:05 EST 23 #cyclesofcirculation e-flux journal #86 — november 2017 Stefano Harney and Fred Moten 05/07 Base Faith precisely, the ana- and anicharismatic sharing of overthrown and out of hand and hand to hand, the homiletic function in and by the there’s a general griot going on. His (and that of congregation. When we say preach when we hear any of his representatives, the ones who must be preaching we be preaching. It’s like a conference representing us but can’t) strategy is exhausted of the birds – a constant rematerialization and and surrounded by our plans. proliferation of the concept; a constant *** socialization of the concept rather than some There’s a movement of the earth against the kind of expedient decree by some kind of self- world. It’s not the movement. It’s not even a appointed consultant who finds himself to have movement. It’s more like what Tonika calls a been gifted with the overlooking and overseeing procession, a holy river come down procession, a power of the overview. The consultant’s capture procession in black, draped in white. The earth’s and redeployment of strategic essentialism is procession sways with us. It moves by way of a faithless and lonely. It exudes the sovereign chant. It steps in the way of the base, in the way religiosity of the nonbeliever. Let me tell you of the dancing tao. It bows to the sisters of the what we need or don’t need, it says, always good foot, carrying flowers from Caliban’s doubling down on you whenever it says “we” with tenderless gardens. The earth is on the move. a heavy, I/thou imposition, a charismatic boom You can’t join from the outside. You come up from that somehow both belies and confirms its under, and you fall back into its surf. This is the sadness in the serial de-animation of its base without foundation, its dusty, watery personal relationships, which is felt by us as the disorchestration on the march, bent, on the run. toxic solace of being spoken to and of by the one Down where it’s greeny, where it’s salty, the earth who is supposed to know. So maybe it’s just a moves against the world under the undercover of matter of where strategic essentialism, strategic blackness, its postcognitive, incognitive worker’s universalism, or the concept, in general, are inquest and last played radio. coming from. Unremitting predication bears a The earth is local movement in the boogie-woogie rumble, where deferred dream desegregation of the universal. Here’s the door to turns to victorious rendezvous. Down here the earth with no return home and who will walk underground, where the kingdom of God is through it is already back, back of beyond, A selection of perfume is featured in this illustration from a Soviet commodity catalog published between 1956-61. 11.08.17 / 13:32:05 EST 24 #cyclesofcirculation 06/07 carried beyon’, caribbean. Pasolini said Ali Blue Stefano Harney and Fred Moten are authors of The Eyes will walk through the door over the sea Undercommons: Fugitive Planning and Black leading the damned of the earth. Ali Blues Eyes. Study (Minor Compositions/Autonomedia, 2013) and ofthe forthcoming All Incomplete. Stefano teaches in But we won’t teach Paris to love. We can’t show Singapore and Fred teaches in New York. brotherhood to London. Ali took Trotsky’s red banners and made something for us – a handkerchief, a bandage, a kiss. × 11.08.17 / 13:32:05 EST 25 #cyclesofcirculation e-flux journal #86 — november 2017 Stefano Harney and Fred Moten 07/07 Base Faith Callon, M. (2009). Civilizing markets: Carbon trading between in vitro and in vivo experiments. Accounting, organizations and so- ciety, 34(3-4), 535-548. 
 
 This journal article by the famed ‘less radical’ Latour, Michel Callon talks about ‘carbon markets’, rather early in their consideration by people like Callon. Carbon markets set a limit or cap of emissions and then allow groups to trade their ‘left over’ emissions they have used. This essay focuses on carbon markets as ‘on-going collective experiments’, which they still are. 26 #cyclesofcirculation Available online at www.sciencedirect.com Accounting, Organizations and Society 34 (2009) 535–548 www.elsevier.com/locate/aos Civilizing markets: Carbon trading between in vitro and in vivo experiments Michel Callon * CSI. Ecole des mines de Paris, 60 Boulevard Saint Michel, 75006 Paris, France Abstract The creation of carbon markets is one of the solutions currently envisaged to meet the widely recognized challenge of global warming. The contributions in this special section of Accounting, Organizations and Society show that many con- troversies nevertheless exist on the ways in which these markets are organized, the calculative tools that are devised to equip them, and the role that they are supposed to play, especially in relation to other types of intervention which favour political measures or technological research. In light of these controversies, the article considers carbon markets as on- going collective experiments. It is argued that carbon trading is an exceptional site for identifying the stakes involved in such experiments and for identifying better what the dynamics of civilizing markets could be. ! 2008 Elsevier Ltd. All rights reserved. In a recent interview on the BBC, Vaclav Klaus, of explicitly raising the question of the role that the very neo-liberal president of the Czech Republic, markets should have in the global warming issue. stigmatized the red ecologists (sic), claiming that But because it is limited to simply reasserting a gen- their actions were a threat to freedom. He added eral dogma, it says nothing about the only question provokingly that the best way of dealing with envi- that really matters, a question considered in detail in ronmental issues, especially the challenge of global this special section of Accounting, Organizations and warming or climate change, was to put all our trust Society: the nature of the markets that should be set in the market. As he sees it, the solution is not less up and their forms of socio-technical organization. but more market, the only appropriate policy being Economists – not those who like Vaclav Klaus to remove all obstacles to its extension and develop- have lost all contact with academic research, but ment. The market frees initiatives, regulates the those who still think about the conditions of the scarcity of resources and, in the long run, stimulates functioning of real markets – fortunately show more the innovations that will provide the solutions to perceptiveness and realism. They have not forgotten humanity’s problems. This extreme position, that economics has devoted a substantial part of its defended by a politician trained in the economics efforts to analysing market failures. Markets do departments of US universities, has the advantage indeed have unquestionable advantages that make them irreplaceable. Through the autonomy with * Tel.: +33 140 519 197; fax: +33 143 545 628. which they endow economic agents, they stimulate E-mail address: michel.callon@ensmp.fr creation and innovation. They are also a powerful 0361-3682/$ - see front matter ! 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.aos.2008.04.003 27 #cyclesofcirculation 536 M. Callon / Accounting, Organizations and Society 34 (2009) 535–548 tool for coordination. Finally, they facilitate adjust- extent on the socio-technical arrangements of which ments and the search for compromises that are not they are made (Callon, 1998; Callon, 2007; Callon & as likely to emerge through other mechanisms such Muniesa, 2005; Callon, Muniesa, & Millo, 2007; as plans. But there are two sides to every coin. Mar- MacKenzie, 2006; MacKenzie, forthcoming; Mac- kets have intrinsic limits and their very functioning Kenzie & Millo, 2003). The design of these arrange- spawns matters of concern. From their first years ments therefore becomes a strategic activity in its at university, all economics student learn that mar- own right which is worth organizing after careful kets are not well-suited to the production of public consideration. The second requirement, related to goods; they are a constant source of negative (some- the first, pertains to the precautionary principle. times irreversible) externalities which affect the exis- No one, not even the best specialists, can be entirely tence of groups whose interests are not taken into sure in advance of the organizational forms and consideration; they can do nothing or next to noth- material agencements needed to establish a market’s ing about income inequalities; and they are not the functioning. Concrete markets can be described and best solution to guarantee everyone’s access to cer- analysed in vivo only, which implies the establish- tain goods such as healthcare. According to econo- ment of devices for measuring, monitoring and mists, these limits are real failures. Of course they watching them, to constantly keep an eye on the do not doom markets as such, but they are an incen- problems they pose and the way in which they react tive to seek solutions and to introduce alternative to certain interventions or adjustments. It is because means so that advantage can be taken of the benefits a market is deployed in an uncertain world that it of markets while attenuating their negative and imposes this mixture of agnosticism and experimen- undesirable effects. Vaclav Klaus remembered only tation, of trials and errors, observation and evalua- half of the lessons he had learned. tion of the effects produced, so typical of a The global warming issue is a good illustration of precautionary approach – in this case applied to what a reasonable approach, attentive to both the socio-technical artefacts and not only technological pros and the cons of markets, ought to be. This is innovations. for instance the approach adopted by Sir Nicholas The first requirement is fairly easy to acknowl- Stern in his now famous report (Stern, 2007). He edge. Because markets are designed they should be contends that global warming, of which the partially designed well, with attention paid to quality so that human origins have been established by scientific all problems are properly identified. Social engineer- research, is the result of a huge shortcoming of eco- ing has the same terms of reference as technical nomic markets. It is a perfect illustration of the engineering and, like it, has to be organized for- damage that negative externalities can cause when mally. The second requirement, easy to accept in they are produced on a large scale without the theory, is probably more difficult to put into prac- effects being felt immediately. Now that scientific tice. An experimental, agnostic approach, open to research has made these externalities visible, tangi- unexpected questions, prepared to carefully con- ble, measurable and predictable, the blindness of sider problems which arise and to hear voices raised, those who still chant on every note that more mar- implies governance structures which are (still) cru- kets will save us from the weaknesses of existing elly lacking. Finally, the two requirements should markets is even more evident, for any extension of not be considered separately. To be validated, markets will naturally also entail new weaknesses. design needs experimentation, and experimentation Stern’s argument seems reasonable, at least in prin- acts in turn on design (Roth, 2007). This tension ciple, as it excludes doctrinarian positions. The mar- between the two, on the basis of which markets ket is simply one solution among others, with its are presented as reflexively designed devices and as advantages and disadvantages; it should neither be on-going scale-one experiments, contributes to rede- diabolized nor considered as a panacea. fining relations between science, politics and eco- In my opinion this pragmatic attitude needs to be nomics, and to raising the question of the framed by two additional requirements. The first mechanisms through which boundaries are drawn relates to the organization of activities concerning between these different worlds. The aim of this market design. In certain respects markets do introduction is to point out some directions for fur- indeed have unquestionable advantages and that is thering our understanding of these mechanisms. why it would be unreasonable not to take advantage From this point of view, reflection on the place, of them. But their efficiency depends to a large organizational forms and limits of carbon markets 28 #cyclesofcirculation M. Callon /Accounting, Organizations and Society 34 (2009) 535–548 537 does not only have the practical advantage of exam- we find in university or industrial laboratories work- ining how the challenge of global warming should ing in the natural or life sciences. be met; it is also a contribution to more general I do not know examples of economic experiments reflection on what civilized as well as civilizing mar- which were shifted several times from one site to kets could be. another while they were under way, alternating between in vitro and in vivo settings. Market mecha- nisms designed and tested in vitro receive much care Markets as on-going experiments and attention when they are first transposed into the real world, but after that they are seldom monitored Recent studies have shown that a growing num- and the feedback that could contribute to making ber of markets are the outcome of genuine processes the theoretical models more realistic is by no means of experimentation. The contexts in which these systematically capitalized on. Symmetrically, eco- experiments take place vary. Using a metaphor bor- nomic experiments run in vivo are usually designed rowed from the life sciences, Muniesa and Callon without planning or even envisaging the in vitro (2007) distinguish between economic experiments phases that would allow for more in-depth reflection run in vitro, that is, in a laboratory1, and experi- on certain mechanisms or fundamental problems. ments run in vivo, that is, in scale-one real markets. The in vitro and in vivo worlds are thus carefully A good example of in vitro experimentation is the kept apart. Yet studies on innovation have shown design and organization of spectrum auctions by that the absence of exchange, interactions, feedback the Federal Communication Commissions (FCC). effects and cross-fertilization is particularly harmful As Guala put it, this is a typical case of market engi- to the innovation dynamic (Kline & Rosenberg, neering which starts with laboratory experiments 1986) (Akrich, Callon, & Latour, 2002). In concrete and in which various economists with their different terms, such interactions can exist, in the case of models are involved (Guala, 2007). As in any inno- markets or any innovation, only if soundly struc- vation process, made of negotiations and compro- tured networks organize relations between the sites mises, the results are then tested outside the at which in vivo experiments are conducted and laboratory, where new interests come into play those at which in vitro experiments are conducted. and new problems arise. From the first laboratory Such networks should allow for the joint and coor- tests, the market is envisaged not only as a nexus dinated advancement of knowledge and theoretical of procedures and rules. Material and especially models on markets, on the one hand, and of market computer devices are a key concern and their design material and institutional devices, on the other. and development fuel debates and reflection, very They could provide the organized framework of often of a theoretical nature. This passage via the coordination and information trading between eco- laboratory is obviously not a general rule. Experi- nomics and the economy. ments can be carried out in vivo or, in other words, in situ, without being prepared in a laboratory. Carbon markets prefigure what could be networks of Mechanisms are set up to identify the effects pro- experimentation on markets duced, the bugs encountered, and the reactions trig- gered, so that they can be taken into account and Carbon markets are an interesting example of the architecture of the markets under experimenta- what these networks of experimentation with mar- tion altered. This happens frequently in cases of kets could be, mainly because they are clearly financial markets, for instance when stock defined as experimental, at least in the EU. exchanges are computerized (Muniesa, 2003). As Anita Engels shows in her contribution, the Whether the experiments are in vivo or in vitro, what actors themselves and especially industrial firms is designed, tested and evaluated is a socio-technical consider that the creation of a carbon market is agencement that combines material, textual and pro- likely to be a long process due to the high level of cedural elements. That is why the notion of an uncertainty surrounding it. This attitude, shared experiment is fitting in such situations: the objects by most of the stakeholders, creates a climate being tested are not very different from those that favourable to critical reflection, negotiation, on- going evaluation, and learning by doing, using and 1 In vitro experiments include modelling activities as well as interacting. These are test markets or, to use a soft- experimental economics. ware term, markets whose beta versions are being 29 #cyclesofcirculation 538 M. Callon / Accounting, Organizations and Society 34 (2009) 535–548 tested. The EU has grounded its action in the same occasions, in different places and forms – initially in logic, with scheduled stages punctuated by reviews, the USA, with the first large scale experimental cap- and emphasis on the fact that certain measures or and-trade programme (1995) for sulphur dioxide. mechanisms are tentative, such as the distribution Experiments have since proliferated, launched either of free allowances rather than the organization of by industrial companies like BP, or national govern- auctions to allocate them. This experimental ments, as in the UK, Norway and Japan. Signifi- approach is found at a more global level with the cantly, all these sites, whether in vivo (universities) invention and establishment of Certified Emission or in vitro (firms, nations, trans-national institu- Reductions (CER) in developing countries, as part tions), explicitly refer to one another. Interactions of the Clean Development Mechanism. The CER have been and are still organized, with capitaliza- are credits, not permits, but can be bought or sold tion on know-how and knowledge, and specialists and have a price and a market value. Unlike emis- circulating between sites. This is truly collective, dis- sion permits, these new ‘products’ do not seem to tributed experimentation deployed in time and be the outcome of prior intense theoretical reflec- space, more or less chaotically or organized, but tion. As fruits of the imagination of innovators in always explicitly. From this point of view the EU the wild seeking a compromise between the is a driving force: as the political history analysed demands of the US and those of developing coun- in detail by Braun (2007) shows, it is a ‘grand new tries, they are perceived as forms of experimentation policy experiment’ that is being implemented. The that are fiercely criticized and trigger numerous intention is clearly to build up competencies, to counter-proposals (Lohmann, 2005; Lohmann, develop a learning dynamic, and to construct net- 2006, this issue). For instance certain NGOs, having works of knowledgeable people and experts from observed that labelled projects cause more environ- all disciplines who commission studies and enrol mental problems than they solve, suggest new eval- both specialists and NGOs. This is how what can uation or certification criteria (MacKenzie, this be called a community of practice (Amin & Roberts, issue). The same uncertainties, trials and errors, 2008) or a collective of research and experimenta- and pragmatic approaches are found in the case of tion on carbon markets has come into being. international organizations responsible for estab- The advantage of studying carbon markets and lishing accounting rules, which hesitate as to the cat- their dynamics appears more clearly now. It can egories to use to reveal these unusual products in serve to further analysis and understanding of the firm’s balance sheets (Cook, this issue). All in all, more general process of constitution of collectives carbon markets seem to be experimental objects, comprising large numbers of different actors from all the aspects and components of which are tested, diverse temporal and spatial horizons, working on reflected on and critically evaluated. the conception and explicitation – mainly theoreti- Carbon markets also prefigure fairly accurately cal – of new market agencements. How, in these col- what interactive networks of experimentation could lectives, do theoretical models and practical be, spread out in time and space. The various con- solutions mutually interfere with and enhance one tributors to this section all refer to the theoretical another? How is this collective work organized? and practical precursors of the European initiative What conflicts run through it? What mechanisms (Braun, 2007). The origins of the constitution of of coordination are used between the various pro- carbon markets lie in certain economists’ theories tagonists or stakeholders? Alongside economics at on the externalities produced by markets. Coase’s large (including accounting, management science, seminal work immediately comes to mind, as well etc.), what role does or could disciplines such as as that of all the authors who have discussed and anthropology, the economic sociology, science and enriched his analyses, especially Dales (1968). With- technology studies, and political science play? out this contribution from economic theory, carbon How are the different knowledge and know-how markets would have been literally unthinkable. But transported, experiences capitalized on, and evalua- the dissemination of models and their enforcement tions conducted? How is professionals’ work orga- in concrete markets requires appropriate logistics. nized? What forms of inter-disciplinarity are set This is where networks of experimentation come up, especially between the social sciences and the in. Before they actually existed, carbon markets natural sciences (when models combine social and were not only conceived of in economics text books, natural entities)? All these questions – and there they were also practised (as in rehearsed) on various are others that could be examined – concerning 30 #cyclesofcirculation M. Callon /Accounting, Organizations and Society 34 (2009) 535–548 539 the modalities of collective experimentation, are rel- collapse if they consisted only of these three groups, evant to the role of markets, their design, and the and carbon markets are a striking illustration of the modalities of their functioning. inadequacy of these models. Simply listing the actors who participate actively, in different ways, Experimenting by taking matters of concern into in their conception and in the experiments concern- account ing them and their evaluation, reveals an infinitely richer and more diversified population. We find The gradual, tentative setting up of these experi- the usual suspects but also scientists – whether they ments on markets is an indisputable fact. The ques- be climatologists, biologists or geophysicists –, tion is nevertheless whether this trend should be grouped together in organizations like the IPCC reinforced. Are such difficult and costly experiments which weigh heavily in the debate, as well as inter- really necessary? Would it not be simpler to rely on national organizations or coordination structures economists’ expertise to devise the required regula- such as OECD, UNCTAD (The United Nations tions, and then leave it up to the agents to organize Conference on Trade and Development), IEA their activities? Is it not contradictory to frame the (The International Energy Agency), or UNFCCC design of markets, institutions which, precisely, rely (The United Nations Framework Convention on on agents’ inventiveness and rationality? Climate Change), professional accounting organiza- An examination, even superficial, of the process tions, academic economists, think tanks, NGOs of of creation ex nihilo of new markets, in which every- various convictions and, last but not least, the com- thing needs to be invented – from the characteristics plex EU administration in Brussels with its national of the goods to the algorithms of pricing or the ramifications, its squads of jurists, and its in-house delimitation of the agents concerned, etc. – shows economists and their models. Each of these agents that neither economists nor the usual economic can and should be considered as economic agents agents can accomplish this gigantic task alone. in their own right: the specialist on greenhouse gas- Not only do they have to cooperate and to accept ses devises a model that constructs equivalence the fact that other actors are involved; in addition, between the different gasses and directly participates in a climate of prevailing uncertainty, even total in fixing the price of emission permits; the accoun- ignorance (regarding the behaviour of natural enti- tant explicates the effects of climate change on the ties and human actors alike), the design process calculation of costs and investments; the economist must necessarily consist of a long process of trial designs market architectures, and so on. and error. The belief used to be that markets were We could argue that not all these actors are gen- quasi-natural realities, and theoreticians were con- uine economic agents because they are situated on tent to identify the conditions of their viability (with the fringes and not at the heart of markets. In my economists playing the role of midwives – or rather opinion this objection is ill-founded, for at least midhusbands! – of markets). We now realize that two reasons. First, the modalities of the organiza- they have to be sometimes created from scratch, tion of carbon markets (like other markets in an and that they are in reality fragile and complicated experimental phase) are particular. Their function- socio-technical artefacts. It is therefore necessary ing includes design and evaluation activities that to reconsider the following basic questions: what constantly trigger reforms and interventions with- are markets made of? How can we ensure that they out which the market would implode due to the function satisfactorily? To these two complicated large number of highly complex problems. As mar- questions, the recent but rich adventure of the car- ket failures are constituent parts of these markets, bon market controversies provides the beginnings and occur constantly, they have to be dealt with of an answer. all the time. Second, in stabilized markets many of ! The setting up of a European carbon market the actors who tend to be considered as marginal has revealed the diversity of actors involved in its or peripheral are clearly present and particularly construction and functioning. For perfectly under- active. In which sectors does one not find NGOs standable reasons, stylized representations of mar- pointing out the ecological or humanitarian stakes, kets tend to reduce the circle of agents to take public- or private-sector economists, consultants, into account, sometimes settling for the basic dis- think tanks, government officials fighting for new tinction between producers, intermediaries and con- rules of the game, or researchers directly involved sumers. Real markets would however rapidly in developing new products that generate controver- 31 #cyclesofcirculation 540 M. Callon / Accounting, Organizations and Society 34 (2009) 535–548 sies? Each of them, even if they are not directly ness and efficiency without taking into account all engaged in commercial relations, actively partici- the assessments, points of view, projects and pro- pates in the design of markets and their functioning. grammes developed by the actors who transform it The case of markets in the experimental phase seems in an on-going (open) experiment. to be appropriate for completing our description of ! What are these controversies about? What are market arrangements. No market is so stabilized, the issues, the matters of concern, that markets pro- routinized, mechanized and purged of all uncer- duce and that the different actors involved in their tainty that it can entirely do without these design functioning highlight, through the questions they activities, including the framing and qualification raise? Studies inspired by STS, devoted to the anal- of goods, the elaboration of rules of the game, the ysis of market socio-technical agencements (Callon, delimitation of agents to take into account, the con- 2007; Hardie & Mackenzie, 2007) are to my mind struction of their calculative equipment, and so on. useful for introducing a tentative classification of Once we have acknowledged this reality, we obtain these issues. a richer and more realistic picture, and at the same The first and most visible issue in the case of car- time a more complex one as we become more atten- bon markets, but one that concerns all markets, per- tive to all the relations that form to enable a market tains to the framing and qualifications of the goods to function. A car, a CER or an emission permit that are traded. In this case it is necessary to identify would not exist and could not enter into market and characterize the various greenhouse gasses. As exchanges without the anonymous crowds of MacKenzie explains in the case of HFC 23, one of humans and non-humans that have participated the problems is to measure in a unanimously accept- and still do participate in its conception, produc- able way their impact on the climate (MacKenzie, tion, distribution and pricing, as well as the organi- this issue). Without the establishment of these equi- zation and supervision of all these relations. valences, no economic valuation can be envisaged. ! The multiple actors engaged in the functioning MacKenzie shows the extent of the scientific, techni- of markets all have their own expectations, concep- cal and metrological investments needed to stabilize tions, projects and interests, on the basis of which the equivalences which, given the prevailing uncer- they promote different modes of structuring and tainties, can be questioned at any time. A second organization. Through their disagreements over issue pertains to the list of actors seen as taking part goods and their qualification, but also over the cal- in the market. Agreement on this point is far from culation of costs and prices, the evaluation of results unanimous, as Lohmann illustrates so well. Unex- or the taking into account of externalities and, more pected actors, orphan or affected groups (to use radically, their differences concerning the role of the terminology that I have proposed in Callon markets in controlling climate change, they reveal (2008)), appear when no one was expecting them, the potential diversity of forms of market organiza- for the good reason that they could hardly have tion. For example certain NGOs consider that the existed as groups considering themselves to be con- best solution is to leave carbon in the ground; others cerned by the functioning of carbon markets before accept the idea of a market, at least as a partial solu- those markets were established. Here we see the dis- tion, and think that clear criteria are needed to eval- possessed farmers; there the enraged neighbourhood uate the demand for CER (gold standard); others inhabitants; elsewhere, in the countries of the refuse the idea that the market can be regulated or North, spreading pollution caused by certain firms accompanied by taxes, and so on. These standpoints which increase their emissions after purchasing cannot be reduced to simple conceptions or ideolog- emission certificates in the South, etc. The prolifer- ical talk unconnected to a reality – that of concrete ation of the actors concerned, whose emergence markets – seen to be external to them; they are, or was impossible to foresee and who sometimes, tend to be, inscribed in devices which can be consid- directly or via spokespersons, end up becoming ered as experimental. Academic economists, who by involved in the designing of markets, is a constant no means agree on everything, are indeed important source of issues to take into account in adjusting players, but they are clearly not the only ones to the market architecture and specifying the modali- think and intervene. Carbon markets show that in ties of its functioning. Calculative equipment, a situation of uncertainty over the state of the mar- whether it serves to establish equivalences between ket, the elements comprising it and the effects that it chemical entities (for example to measure their is likely to produce, one cannot judge its effective- effects on global warming), to price goods, to orga- 32 #cyclesofcirculation M. Callon /Accounting, Organizations and Society 34 (2009) 535–548 541 nize encounters between supplies and demands that works correctly?’, they suggest the following (auctions or other mechanisms), or simply to mea- answer: it is a market which welcome and recognize sure emissions, is also the subject of stormy debates as one of its most central constituent elements all and lies at the heart of the structuring of carbon the actors who demand to be taken into account, markets. The list could be lengthened. It would including those who are considered as marginal or show that each of the operations contributing to on the verge of exclusion, with their points of view, the formatting of the market socio-technical agenc- their matters of concern, their proposed tools, fra- ements2 is found in a controversial and unstable mings and models. It is this dynamic tension, in form in the case of carbon markets. In other words, which constant unexpected concerns are expressed the description of the market and its functioning, and ask to be heard and to be taken into consider- that is, what the market is and what it does, cannot ation, that defines a ‘good’ market (Law, 2004). be separated from the multiple controversies con- The question here is obviously about the organiza- cerning it, in which as many different versions are tion of this dynamic. It calls for specific solutions proposed. to each market, and finds answers only at the cost Carbon markets thus invite us to enrich our con- of an effort to organize the design and experimental ceptions of markets. Markets are not only devices activities of markets. enabling well-identified agents to defend their inter- ests and to organize transactions so that they can Politicization, economization and scientization: from reach satisfactory compromises efficiently. At the (stem) issues to networks of specific and differentiated heart of markets we find debates, issues, feelings, problems matters of concern, dissatisfaction, regrets, and plans to alter existing rules, which cannot be inter- A market which functions satisfactorily is one nalized once and for all because they are linked to that organizes the discussion of the matters of con- irreducible uncertainties, to what I have called fra- cern produced by its functioning and the framings/ mings which are never either definitive or unques- overflowings that it entails. It takes those matters tionable. This ‘‘hot” component of markets, which of concern into account and sets up procedures causes them to be in a constant state of disequilib- and devices designed not only to encourage the rium, traversed by forces of reconfiguration, is not expression of problems which arise but also to facil- always present to the same degree but it always itate the design and evaluation of theoretical or exists. The tension between the cold source and practical solutions to those problems. A definition the hot source is a component of markets. In the such as this, which grants centrality to on-going case of those still in an experimental phase, such open experiments and to the debates and controver- as carbon markets, the hot source is preponderant, sies accompanying them, closely links distinctly eco- for uncertainties are expressed through it. These nomic activities and those that one would tend to markets, which act as magnifiers, show us that qualify as political and that markets tend to exclude which is usually concealed or which we get rid of from their ambit. That is why the explicitation of too readily by talking in terms of failures. I believe problems revolving around the various framings/ that it is more accurate and fertile to consider that overflowings mentioned above and their ‘‘manage- any market includes both of these components. Car- ment” are not self-evident. Some think that it entails bon markets impose a new view of concrete mar- the risk of transforming markets into political are- kets. To the question: ‘what are they made of?’, nas. Many others perceive it as a pollution of eco- they beg us to answer: of all the existing or emergent nomic institutions by events that are out of place actors who are concerned by their functioning and in them. Carbon markets show however how sterile involved in clarifying the problems and issues that this view of the economy can be. These markets can they generate. To the question: ‘what is a market develop legitimately and efficiently only if they ren- der such controversial events visible and debatable, as a source of material for experimentation. In 2 Callon and Caliskan (submitted for publication) propose a short, for markets to function, in the sense defined provisional list of these framing activities, including: framing of above, there have to be arrangements, procedures passive goods and disentangling them from active human agencies; framing and qualifying calculating agencies; enframing and devices which are clearly not outside of them the market encounter; producing the price; market maintenance; but, on the contrary, become an essential compo- objectifying «The Economy». nent of them (Callon, 2008). 33 #cyclesofcirculation 542 M. Callon / Accounting, Organizations and Society 34 (2009) 535–548 To analyse these nascent market configurations social constructivism (that which is considered as in which economics and politics are combined, it political, economic and scientific is simply the result would be tempting to say that in any market, as in of a clash between groups struggling to impose their any activity, whether economic or not, there are own points of view) and essentialism (there are one implicit politics that we could call sub-politics or more definitions of politics, economics and sci- (Beck, 1992) and that need to be identified clearly ence, which provide objective criteria enabling us if we are to get rid of them. In short, the aim would to say, a priori, whether a behaviour, way of think- be to purify the market of the slag polluting it, to ing or device is political, economic or scientific). remove the unsolved political issues disrupting its Since they are markets in an experimental stage, functioning, to externalize them and then, after a which simply highlight a feature common to all political debate, to revert to that market to frame markets, they are a remarkable site for studying this and regulate it better. Recent developments in the process of joint reconfiguration. application of STS to the study of economic activi- ties have however shown the counter-productive (Stem) issues and problematizations nature of this type of approach. The distribution between the political and the economic is not ante- As Marres (2007) shows, the best starting point rior to the market; it is the outcome of the function- for studying this process of politicization is the ing of markets, of which it is a by-product, in a notion of an issue or matters of concern. In the sense. The short history of carbon markets clearly case under study here, the issue – at the origin of illustrates this point. Their construction is not pri- the initiatives presented in this publication – is cli- marily about the drawing of a boundary that clearly mate change and particularly one of its compo- and unquestionably separates the political in their nents, global warming. I propose to reserve the functioning from the economic. Carbon markets term issue for such situations of initial shock, defy this type of division. They produce issues, mat- where there is still no indisputable formatting ters of concern that no one is sure whether they enabling us, for example, to say with any certainty should be addressed politically, economically or that it is a strictly (or primarily) political, economic techno-scientifically. or scientific issue. We will therefore talk of an issue The carbon market experiment can be described when the available codes, irrespective of what they as a threefold process of joint problematizations at are, fail to answer the questions raised by this issue the end of which the problems to be treated by (Barry, 2001). This is indeed the case of global either markets or political institutions or scientific warming which defies all attempts to reduce it to institutions will temporarily be distinguished. We a problem that is either strictly economic or polit- know, and Nicholas Stern acknowledges this in his ical or scientific/technical. Of course those who try report, that all three treatments are inevitable, but to perform such reductions are not discouraged by we do not yet know with precision how the distribu- such polymorphism, but they all come up against tion will or should be made. This approach implies overwhelming difficulties. Whoever accuses capital- that neither economics nor politics nor science can ism or the market of being the source of all our be considered as realities that have been stabilized problems, and claims that global warming is above for once and for all. What an economic market is all an political problem requiring political solu- and what it can do are the result of on-going exper- tions, is suddenly confronted with economic issues imental processes and series of trials of strength, the that strike back. Whoever thinks that the issue is at outcome of which is not predictable. The same last scientifically and technologically under control could be said for what can be qualified as political is soon faced with political demands that point out or scientific. the persistence of glaring injustices and the result- By adopting this point of view of economy, pol- ing economic waste. Global warming in its current itics and science in the making, are we not likely to state is an issue that is unqualifiable, not in theory sink into confusion and relativism? A few comments but in practice, for no framing is able to embrace it are called for to reassure those who may be afraid of in its entirety. As the roots of the word indicate, an such an eventuality. Carbon markets are, once issue always finds an exit enabling it to overflow. It again, going to be very useful in helping us to under- is protean, constantly changing as it spreads, irre- stand why we are not condemned to choosing spective of the frame into which we try to fit and between the devil and the deep blue sea, between enclose it. 34 #cyclesofcirculation M. Callon /Accounting, Organizations and Society 34 (2009) 535–548 543 Issues can be compared to stem cells which, as we one aspect of the more general issue of growth know, are not yet differentiated and are therefore and its legitimacy. For those who think that all described as totipotent. They are an original state our problems stem from there, no problematization from which all the cells comprising the organism of global warming is acceptable. They demand that derive. Depending on the circumstances and the tra- the issue not be divided up, and that it be put back jectory followed, they become liver or heart muscle into a more general issue that makes it even less cells, for example, or neurons of the cerebral cortex. divisible! The movement downstream, towards Before reaching this state, they go through various highly specifiable and treatable problems, is thus stages of specification (we talk of pluripotent, mul- refused. Basically the demand is that the issue tipotent, unipotent and then specialized cells) at remain a stem issue, through a movement of ampli- which they can veer off in a different direction fication going upstream. Another, at least tempo- towards other destinies and types of activity. Noth- rary, source of failure of problematization may ing in a stem cell determines its future as a liver or stem from the opposition that it triggers: certain heart cell, for example. Moreover, the changes it groups are opposed not to the division of the issue undergoes do not seem to be irreversible, for stem but to the way in which it is split up and reduced, cells can be obtained from highly specialized cells. like those who, for example, refuse the boundaries Issues are very much the same: they have a multi- imposed by the Stern report between economic plicity of fates, specifications, qualifications and treatment and technological treatment of the abate- regressions, all equally possible and probable, but ment of greenhouse gasses. some of which will materialize only later, depending When undertaken, this multiform problematiza- on the circumstances and trials encountered. Global tion leads to the constitution of a network of prob- warming is an issue (we could say a stem issue!) that lems (what I called a problematic networks: Callon, is gradually being split into a series of distinct prob- 1980) whose content and extension evolve in rela- lems, some of which are qualified as political and tion to the translations that are attempted between others as economic, technological or scientific. Let problems. It is contingent on the configurations in us call problematization this gradual process of frag- place when the (stem) issue becomes public. In other mentation and division of issues that evolves into words, the division of (stem) issues into specific the joint formulation of a set of different problems problems, some of which are qualified as technical which in a sense, at least partially, are a substitute and others as economic or political, as well as the for the initial issue (on the notion of problematiza- formulation and explication of these problems, are tion see Dewey (1916), Callon (1980) and Rabinow not random. For example, the possibility of seeing (2005); on the notion of the division of problems, the emission of greenhouse gasses as a consequence see Barthe (2005)). Problematization is a multiform of market failure (negative externalities), stems from dynamic since, in general (and this is what is hap- the state of economic theory, from what it says pening in the case of climate change), the questions about the limits of any market but also about the (political, economic, etc.) it leads to are both distinct existence of a largely common agreement on what from and interdependent on one another. Instead of economic markets are and the way they function talking of global warming, people increasingly refer (well or badly). Likewise, being able to contend to market efficiency, negative externalities, develop- without any fear of being contradicted, that it is ing countries’ right to development, international conceivable to develop technologies to abate emis- politics, technological innovations to promote, sions, proves that science and technology have research to undertake, and models to improve, with reached a degree of maturity, robustness and objec- each of these topics being closely bound to the tivity that makes the legitimacy of certain evalua- others. tions and projects unquestionable and inevitable The dynamic of problematization of (stem) issues (at least in the fields concerned). We would need is a complex process, probably even more complex to continue this inventory to show in detail and con- than that of the differentiation of (stem) cells! The vincingly how the instituted configurations weigh on transformation of an issue into well-identified prob- current problematizations. In turn – and this is an lems – which can be addressed by planning specific open research question – the way in which problems actions – is never completely consensual nor total. are eventually formulated, the treatment chosen and For instance, in the case of climate change, some the solutions proposed and implemented, act on the are still convinced that global warming is simply existing configurations and contribute to changing 35 #cyclesofcirculation 544 M. Callon / Accounting, Organizations and Society 34 (2009) 535–548 them. The way in which the organization and func- between the different greenhouse gasses. MacKenzie tioning of economic markets are designed will most (this issue) shows that this measure, based on scien- certainly emerge profoundly changed from the mul- tific modelling and metrological innovation, impacts tiple and complex experiments in the European car- on carbon pricing. Hence, the economic problem bon market. Likewise, what we know or think we rapidly becomes a complex technico-scientific prob- know about technologies, equivalences between lem. The machine producing interdependent prob- greenhouse gasses, or the dynamics of climate lems is running again. Sir Stern’s nice neat change and of the distribution between anthropic framings become jumbled and call for the definition and non-anthropic causes, will be altered drastically of new boundaries. The same creative confusion by the research undertaken in coming years and occurs if we start with a question such as: how consequently what might be considered as scientific can we scientifically evaluate, and thereby econom- or technical questions will be redefined. Even the ically value, the effects in terms of greenhouse gas limits between established spheres will be revised: abatement of replanting a forest in a rural area of markets which constantly take into account the Brazil? Driven by attempts to make this protean multiple externalities that they produce – especially issue of climate change manipulable and manage- the constitution of concerned groups scattered able, the formulations of problems proliferate and across the globe, unable to be heard and suffering react to one another. Instead of a shock, trauma from the effects of economic measures intended to or complex issue, a dense network of problems abate greenhouse gas emissions – will no longer appears, constantly moving as each problem is resemble markets as we know them today. They will borne by one or more actors who identify with it. force us not only to revise our market theories and Carbon markets are an ideal site for studying the our common conceptions of their functioning but dynamics of this (never ending) process of joint also, above all, to alter our ways of distinguishing problematization. political and economic processes. As I have shown elsewhere (Callon, 2008), these markets of a new Trajectories of problematizations? kind, which seem more open and civilized than those to which we are accustomed, combine devices It is this multiform process of problematization that we previously attributed either to the economy of (stem) issues that we need to follow and study, or to expression and political action. This redefini- so that we can avoid the two stumbling blocks men- tion of the boundaries between categories of prob- tioned above, essentialism and relativism, for the lems and activities, as the problematization networks of problems stretch between the two. advances, seems inevitable even if we have very Dependent on existing categories but not deter- few ideas on how it happens and the conditions mined by them, they are powerful machines of favouring or impeding it. social reconfiguration. The dynamics of problemati- I am convinced that carbon markets are an zation does not obey a logic set in advance; in other exceptional opportunity for furthering our knowl- words, there are no natural trajectories that, in one edge of these mechanisms and studying the transfor- way or another, the problematization of (stem) mation of (stem) issues into networks of problems, issues follows. This is where the analogy between the resolution of which is attended by a (partial issues and cells stops, for cells change by following and limited) reconfiguration of economics, politics paths that may be unpredictable but consist of pre- and science, and relations between the three. Take, determined steps. We can nevertheless posit (as a for example, the multiple and interdependent fra- provisional hypothesis) that the process of proble- mings proposed by the Stern report with its careful matization of issues, in so far as it is contingent delimitation of what has to be treated by either the and singular, obeys rules which are generally market or political institutions or the technoscienc- describable. es. Do we accept this division and try to address The fact that (stem) issues do not follow typical economic problems, for example by deciding to trajectories that a natural history of issues could somehow combine taxes and the auctioning of emis- describe, is illustrated by the case of global warming sion allowances? This is where we immediately and carbon markets. The context in which the cli- stumble against issues that flow over the set frame mate change issue appears and the nature of the (even if we have decided to concentrate only on eco- institutions that host and promote it (the IPCC, nomic aspects), such as the question of equivalences the Rio Conference, the Kyoto Conference, Euro- 36 #cyclesofcirculation M. Callon /Accounting, Organizations and Society 34 (2009) 535–548 545 pean multilevel governance) orient its treatment in tory of economics, its rules of functioning and its certain directions which depend on on-going con- organization. The effects are felt all the way through troversies and experiments. Greenhouse gasses do to the theoretical activity of market analysis. They not disturb the world and do not contribute to affect economic modelling itself, which is thus con- changing it in the same way as GMOs or over-fish- fronted with problems that it had not entirely solved ing in the Atlantic Ocean. To be sure, carbon mar- or even perceived (for instance equivalence or non- kets are a good laboratory for studying social equivalence, in terms of market efficiency, between redifferentiation, but we must be careful not to seek carbon taxes and the auctioning of emission allow- general laws on the evolution of issues therein. Our ances). Thus, step-by-step, a complicated political focus should rather be on devising analytical catego- economics is constructed, which takes current pro- ries for understanding the processes of problemati- blematizations into account. By ricochet, politics zation that these markets amply illustrate. itself is at least partially redefined. Procedures of As experimentation progresses, new forms of consultation are transformed, to take just this one, organization and socio-technical agencement of now well-documented example (Callon, Pierre, & markets are invented, for unexpected questions Yannick, 2001). NGOs become legitimate and arise, to which answers and at least temporary solu- unavoidable partners, and the emergent concerned tions are needed. I have already mentioned several groups who demand, through spokespersons, to be of them, presented in the articles in this section: a heard and taken into consideration, can no longer possible combination of carbon taxes and emission be completely ignored. The way of organizing the trading; the invention of certificates to enable devel- international public sphere and of making visible oping countries to participate in the collective emis- problems qualified as political, changes as the orga- sion-abatement programme; the development of nization of markets evolves. Science ends up being pricing tools; compromise between free allocation transformed and redefined: first, in its content, for of allowances and auctioning; and modalities of models explicitly combine economic with climato- treating allowances in firms’ accounting. We could logic and geophysical variables, and there is no rea- also mention (Braun, 2007) the debate on whether son for this interdisciplinary integration to stop; and it is preferable to organize carbon trading upstream second, in its organization, with the constitution of or downstream, and on the interesting point of who a world parliament of specialists (the IPCC) who, should be imputed with the responsibility of emis- like any political assembly, negotiate the content sions and therefore the allocation of allowances (is of their reports among themselves and vote on sci- China responsible for its industry’s emissions, or entific facts before making them public and passing the consumers in the US who buy its cheap prod- them on to policy-makers. One day, for sure, this ucts?). These problems, peculiar to the ‘global parliament will have to break open the circle of pro- warming’ issue and to the particular circumstances fessional expertise; it will have to bring into the in which it appears and prevails, stimulate the research collective researchers in the wild attentive inventive and creative capacities of actors who are to the events affecting emergent concerned groups. prompted to devise appropriate solutions. The shock of climate change has already triggered This creative activity, whose outcome is strongly a series of other changes, of a different nature, in dependent on the specific nature of issues and prob- the way of designing and doing economics, politics lems that are being debated, is the main source of and science, but also of distributing problems the new differentiations proposed and tested during between the three. This threefold process which, the problematization process. Those who design through the treatment of issues and their multi-pro- and implement carbon markets by answering the blematization constitutes a joint process of politici- questions that appear to them (or are put to them), zation-economization-scientifization, constantly try not to remain locked in existing frames. They produces new differences from existing ones and test the fault lines or the biggest weaknesses of the attributes new significations to economics, politics existing agencements and, by following the gradients or science. of resistance favourable to them, distinguish These reconfigurations, designed to deal with between that which will be considered as political global warming as a very specific issue, could turn and that which will be taken in charge and delegated out to have a more general impact, so that the solu- to the market and thus to the economy. The conse- tions tested in this specific case can be adapted and quence is an at least partial redefinition of the terri- transposed to other situations. That is why it is 37 #cyclesofcirculation 546 M. Callon / Accounting, Organizations and Society 34 (2009) 535–548 interesting to consider, at least in simple terms, for The way of practising science and producing exploratory purposes, whether these reconfigura- knowledge could likewise be affected profoundly. tions and the redistributions that they entail can The creation of the IPCC – a radical innovation in be characterized in general terms. the organization of research and the procedures Market organization could henceforth explicitly for validating scientific facts – as well as the engage- include a set of actors who were formerly on the ment of a multitude of experts from a wide variety fringes of markets and are now at their centre. Car- of organizations (mainly NGOs), point to a new bon markets provide what is, in my opinion, a fairly type of community or rather a research and innova- good idea of that list mentioned above, which tion collective which, I predict, will spread through includes scientists, specialists in the natural sciences many sectors if the appropriate adjustments are (such as climatologists or geophysicists) or the made. social sciences (such as economists, anthropologists In this emergent configuration – which has inher- or sociologists), accompanied by a squad of experts ited from the preceding one but is also reshaping it and representatives from NGOs, think tanks, inter- profoundly –, with markets thus revamped, political national bodies and other political administrations. devices and procedures rearranged, and research To be considered as efficient, a market should pay and innovation collectives redesigned, the same very careful attention to the numerous matters of actors regularly participating in all three forms of concern that it creates, and to the groups that activity remain distinct but are now explicitly express and promote them, thus becoming economic inter-related. It is moreover this overlapping that agents in their own right. This surely requires that allows for the multi-problematization of issues and the usual market mechanisms (revolving around, their treatment ‘in batches’, as they are sliced up for example, rules of competition, circulation of into as many specific problems to solve. It might information, etc.) be completed by a set of proce- be that we are moving away from a world broken dures and devices designed to compile the list of up into spheres, with a two-way trade between actors to involve, but also to make an inventory them; but the new world we are entering into has of matters of concern, to make them explicit and not for all that abolished the differences: it simply debatable, and to organize experiments and evalua- distributes and treats them differently. tion of solutions devised and then adopted. The political devices that take shape before our Conclusion eyes could also be transformed by this still emerg- ing reconfiguration of markets. In their new form I hope that the articles in this special section will they are destined to include actors who ask ques- convince the reader that carbon markets are an tions not only on the role of the market (in the sin- exceptional field for furthering our understanding gular), which is not unusual, but above all on the of the joint processes of economization, politiciza- actual organization and on the effects of particular tion and scientifization through which the forms markets (in the plural). The social engineering of of organization of economic, political and scientific markets could thus become an explicitly political activities, their mutual relations and the challenges issue. This could lead to actors hitherto excluded they are designed to meet, are redefined. In the from or considered as external to the world of pol- establishment of carbon markets we are witnessing itics being granting an unusual place and role in a redistribution of economics, politics and science, the debates but also in decision-making processes. which does not eliminate differences but, by main- For this to happen, the creation of procedures that taining these distinctions, refuses to consider that we have proposed to call dialogical could be their content is immutable. The social sciences, demanded. The idea would be to allow for all the along with the knowledge elaborated by the actors, actors concerned by the design and functioning are stakeholders in these processes of experimenta- of a particular market to be identified and to tion consisting of constant feedback on the signifi- express themselves, and then for their analyses cance and impact of what is under way and on the and proposals to be compared. Active participa- measures to take (which will affect current differen- tion in the negotiations and debates by scientists tiations between economy, politics and science). I and experts, whether they are confined researchers think that they could be instrumental in clarifying or researchers in the wild, would be encouraged the new models whose emergence and establishment (Callon et al., 2001). we are witnessing and, why not, in their possible 38 #cyclesofcirculation M. Callon /Accounting, Organizations and Society 34 (2009) 535–548 547 generalization and transposition. How, in these con- carbon markets in social-science perspective, Institute of ditions, can a civilizing process not come to mind, Advanced Study, Durham University, England. since in the final analysis this is a matter of plunging Callon, M. (1980). Struggles and negotiations to decide what is problematic and what is not: The socio-logics of translation. markets back into the social fabric which they help In K. Knorr, R. Krohn, & R. Whitley (Eds.), The social to create and which, in turn, constitutes the frame- process of scientific investigation (pp. 197–220). D. Reidel work of the questions, expectations and needs to Publishing Company. which they try to respond. The challenge of climate Callon, M. (Ed.). (1998). The laws of the markets. London: change could be one of the first opportunities on a Blackwell. Callon, M. (2007). What does it mean to say that economics is planetary scale to raise the question of how to better performative?. In D. MacKenzie F. Muniesa, & L. Siu (Eds.), civilize markets. The term civilizing markets, which How economists make markets. The performativity of econom- I have chosen, following MacKenzie, as a title for ics. Princeton, NJ: Princeton University Press. this introduction, is even richer in meaning (Latour, Callon, Michel (2008). An essay on the growing contribution of forthcoming). Not only do markets need to be civi- economic markets to the proliferation of the social. Theory, Culture & Society, 24, 139–163. lized, that is, to be included in this multi-problema- Callon, M., & Caliskan, K. (submitted for publication). Econ- tization that is a living source of questions, research omization: New Directions in the Studies of the Market. and the invention of satisfactory answers; but sim- Callon, M., & Muniesa, F. (2005). Economic markets as ply by participating in this movement they can act calculative collective devices. Organization Studies, 26, also as a civilizing force in politics and science. Civ- 1129–1250. Callon, M., Muniesa, F., & Millo, Y. (Eds.). (2007). Market ilization may be this never-ending effort to trans- devices. London: Blackwell. form unsolvable issues into solvable problems, and Callon, M., Pierre, L., & Yannick, B. (2001). Agir dans un monde thus to prove right Marx’s claim that humanity incertain. Essai sur la démocratie technique. Paris: Le Seuil never asks itself questions that it cannot solve. But (English translation to pe published by MIT Press). we still need to establish why it asks itself certain Dales, J. H. (1968). Pollution, property and prices. An essay in policy-making and economics. Toronto: University of Toronto questions rather than others, and that, in my opin- Press. ion, is the whole point of studying civilizing Dewey, John (1916). Essays in experimental logic. New York: markets. Dover. Guala, Francesco (2007). How to do things with experimental economics?. In D. MacKenzie F. Muniesa, & L. Siu (Eds.), Acknowledgements Do economists make markets? On the performativity of economics (pp. 128–162). Princeton: Princeton University I wish to thank Ash Amin, Donald MacKenzie Press. and Sue Smith for their invitation to the workshop Hardie, I., & MacKenzie, D. (2007). Assembling an economic that they organized in Durham (Institute of Ad- actor: the agencement of a hedge fund. 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In Paper presented at the workshop 107–145. 39 #cyclesofcirculation 548 M. Callon / Accounting, Organizations and Society 34 (2009) 535–548 Marres, N. (2007). The issues deserve more credit: Pragmatist of economics (pp. 163–189). Princeton: Princeton University contributions to the study of public involvement in contro- Press. versy. Social Studies of Science, 37, 759–780. Rabinow, P. (2005). Midst anthropology’s problem. In A. Ong & Muniesa, F. (2003). Des marchés comme algorithmes : sociologie S. J. Collier (Eds.), Global assemblages: Technology, Politics, de la cotation électronique à la Bourse de Paris. In Centre de and ethics as anthropological problems (pp. 40–53). Malden, Sociologie de l’Innovation (pp. 453). Paris: Ecole des mines de MA: Blackwell. Paris. Roth, A. (2007). What have we learned from market design. Muniesa, F., & Callon, M. (2007). Economic experiments and the Working Paper. construction of markets. In D. MacKenzie, F. Muniesa, & L. Stern, N. (2007). The economics of climate change. The Stern Siu (Eds.),Do economists make markets? On the performativity review. Cambridge: Cambridge University Press. 40 #cyclesofcirculation Baena-Moreno, et. al (2019). Carbon capture and utilization technologies: A literature review and recent advances. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 41(12), 1403-1433.  This is a straightforward, if technical academic paper on a list of carbon capture and utilization technologies and applications. The paper covers different ends of the carbon capture spectrum —  from R&D, academic studies, to commercial uses of carbon dioxide. 41 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 2019, VOL. 41, NO. 12, 1403–1433 https://doi.org/10.1080/15567036.2018.1548518 Carbon capture and utilization technologies: a literature review and recent advances Francisco M. Baena-Moreno, Mónica Rodríguez-Galán, Fernando Vega, Bernabé Alonso- Fariñas, Luis F. Vilches Arenas, and Benito Navarrete Department of Chemical and Environmental Engineering, School of Engineering, University of Seville, Sevilla, Spain ABSTRACT ARTICLE HISTORY This paper presents a comprehensive list of Carbon Capture and Utilization Received 7 July 2018 technologies and applications, ranging from lab-scale R&D activities reported Revised 26 September 2018 in academic papers to commercially established uses of carbon dioxide. Accepted 14 October 2018 Carbon dioxide, as a source of carbon, has the potential to be used as KEYWORDS a solvent, as a raw material in the manufacturing of fuels, carbonates, poly- Carbon capture and mers, and chemicals, or as a recovery agent in techniques such as enhanced oil utilization; CO2 as feedstock; recovery or enhanced coal bed methane. In this paper, a literature review and life cycle assessment; recent advances of each technology are explained. To finish, most relevant Life environmental impacts; Cycle Assessment studies carried out by experts in this field are included. mineral carbonation Among the different alternatives studied for the use of carbon dioxide, the processes of carboxylation, consisting the synthesis of carbonates and carbox- ylates, have stood out. Both the production of salicylic acid as well as that of dimethyl carbonate and mineral carbonation are presented as the most likely applications of carbon dioxide, at least, in the short term. Introduction The concern for climate change is one of the key agendas stated by world leaders and experts on the subject, as well as in the daily conversations or the media every day. Carbon dioxide (CO2) emissions are considered the main cause of this concern. Therefore, it is logical to think that the solution to this problem lies in the reduction of these emissions (Aresta 2010; European Comission 2016; Hatzigeorgiou, Polatidis, and Haralambopoulos 2010). Figure 1 represents monthly CO2 concentration values. As can be seen in Figure 1, CO2 emissions have increased by approximately 2 parts per million per year. Currently, the direct reduction of the aforementioned emissions is complicated in the short term, due to the established technologies in different industries, basedmainly on the use of fossil fuels. As a consequence, the concept of Carbon Capture and Storage (CCS) emerges as an attractive idea for the reduction of emissions, where, among others, absorption has been proved as an efficient technology to achieve a high capture yield with different solvents, such as monoethanolamine (MEA) or piperazine (PZ) (Li and Zhang 2018; Vega et al. 2017; Zhang 2016; Zhang et al. 2018a), but with certain technical and economic limitations like, for instance, the high energy penaltymainly due to the thermal regeneration of thementioned solvents (Bilgen 2016; Zhang et al. 2018b). On the other hand, a common issue for all CCS technologies is the high requirement of CO2 gas storage capacity (IPCC 2005). Carbon Capture and Utilization (CCU) seeks not only to reduce the volume of emissions to the atmosphere but also to obtain a benefit through the use of CO2 in different types of industrial processes, replacing conventional raw materials (Aresta 2010; Bilgen 2016). These methods will not be enough to achieve the desired objective, but they could be the key to complement the use of carbon-free renewable technologies, together with the awareness of the population (Princeton University 2015). This paper CONTACT Francisco M. Baena-Moreno fbaena2@us.es Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/ueso. © 2019 Taylor & Francis Group, LLC 42 #cyclesofcirculation 1404 F. M. BAENA-MORENO ET AL. Figure 1. Monthly record of the concentration of CO2 in the atmosphere. Adapted from Scripps Institution of Oceanography (2018). analyzes the main available CCU technologies, as well as the innovative studies carried out so far by experts in this area. Finally, some Life Cycle Assessments (LCA) that have been done by other authors for promising CCU options are presented. The studied technologies have been grouped in four categories as shown in Figure 2: CO2 as a solvent, Chemicals from CO2, Fuels from CO2, and Enhanced Oil Recovery (EOR) & Enhanced Coal Bed Methane (ECBM). CCU technologies The use of CO2 can be technological, biological or chemical, and all of them seek to improve or replace traditional processes with the incentive of contributing doubly to curb climate change: it would reduce CO2 emissions into the atmosphere and could lead to a reduction in the extraction of Figure 2. CCU technologies included in this study. 43 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1405 CO2 from fossil fuels, as well as an economic saving for companies that consider their use (Abdeen et al. 2016a; Aresta 2010; Aydin 2014; Cuéllar-Franca and Azapagic 2015). On the one hand, the direct or technological use of CO2 includes applications such as the extraction of compounds with supercritical CO2 (scCO2), dry cleaning, water treatment, and food industry uses, among others. In the case of the food industry, CO2 is utilized as a replacement for the toxic elements used for food disinfection (e.g. n-hexane) as well as a replacement of the organic solvents in the extraction of compounds and finally replacing dangerous acidic species in water treatment (Aresta 2010). On the other hand, for the biological use, it is worth mentioning the direct fixation of CO2 in fast-growing biomass. This can help to reduce the accumulation of CO2 in the atmosphere much quicker than would naturally occur. This procedure can be used both for the manufacture of chemical products and for the production of energy, for example, converting that biomass into gaseous or liquid fuels instead of directly burning the biomass. A clear example of this fast-growing biomass is photosyn- thetic microorganisms or microalgae (Aresta 2010; Cuéllar-Franca and Azapagic 2015). Finally, the chemical use consists of the conversion of CO2 into other products, such as methanol, acetic acid, carbonates, and polymers, among others (Aresta 2010). CO2 as a solvent The use of solvents in the chemical industry involves large costs, both environmental and economic. The use and separation of solvents entail the use of many unit operations in the manufacturing of chemical products, representing a high percentage of the energy consumption of the process. From the environmental point of view, the organic solvents used in the chemical industry generate a negative impact, due to its flammability, smog formation, its toxicity, and the risk of inhalation, also affecting human health. This is why a considerable amount of research in the field of sustainable chemistry revolves around the development of new ecological solvents. The ideal solvent would be non-flammable, non-toxic for both humans and the environment, abundant, renewable, highly stable, low cost, easy to prepare, and separate from the final product (Albo et al. 2013; Aresta 2010; Lee et al. 2017; Marriott, Jessop, and Barnes 2014; Wang et al. 2016a). Under these conditions, CO2 appears as a possible candidate, which seems to meet all the criteria, except that related to global warming. Even so, this CO2 does not generate this effect directly, since it is a recycled material obtained from a waste. However, the contribution to global warming would be generated by the use of the energy necessary to compress the CO2 to a liquid or supercritical state. This operation involves a generally high cost, which must be taken into account when comparing it with the energy consumption of conventional solvents (Beckman 2004; Boyère, Jérôme, and Debuigne 2014; Cuéllar- Franca and Azapagic 2015; Marriott, Jessop, and Barnes 2014). CO2 can be used as a solvent in both liquid (lCO2) and scCO2 states. A pure gaseous component is considered in a supercritical state when its temperature and pressure exceeds its critical values, for CO2 these are 304.1 K and 7.4 MPa, respectively (Boyère, Jérôme, and Debuigne 2014). Its easily accessible critical point, high diffusivity, low viscosity, and surface tension make CO2 even more attractive as a solvent (Albo et al. 2013; Aresta 2010; Boyère, Jérôme, and Debuigne 2014; Lee et al. 2017; Linstrom and Mallard 2014; Marriott, Jessop, and Barnes 2014; Wang et al. 2016b). Properties of the solvents can be expressed through different parameters such as dipole moment, dielectric constant, refractive index or solubility degree. ScCO2 has characteristic properties of non-polar solvents, such as n-hexane. Table 1 shows some properties of lCO2 and scCO2. Table 1. lCO2 and scCO2 physical properties. (Hyatt 1984; Marriott, Jessop, and Barnes 2014). Solvent Density (kg/L) Viscosity (Pa· s) CP (25°C) (kJ/kg· K) Reichardt Scale Polarity Dielectric Constant (F/m) scCO 0.956 a 1.060 x 10–4 C2 0.846 C 0.090 (Var) 1.10–1.50 lCO2 1.000 B 1.200 x 10–4 E 3.140 D 0.090 (Var) 1.50 a 40°C and 400 bar B 20°C and 65 bar C 40°C D 10°C E 25°C 44 #cyclesofcirculation 1406 F. M. BAENA-MORENO ET AL. Dielectric constant of scCO2 and lCO2 is similar to n-hexane (2.00 F/m) (Mopsik 1967). However, the solvency power measured on the Reichardt scale suggests that scCO2 and lCO2 are more polar than n-hexane (0.09 vs 0.009 presented by n-hexane) (Marriott, Jessop, and Barnes 2014; Ren et al. 1999). Initially, scCO2 was proposed for extractions and fractionation in the field of natural product processing. Some of the commercial processes that began to be performed with CO2 were the extraction of hops, decaffeination of coffee and tea, and the extraction of flavors, spices, and essential oils from botanical material. Even so, it has not been until the last twenty-five yearswhen there has been an increasing interest in the use of this unconventional solvent as a substitute for liquid organic solvents (Aresta 2010; King and Bott 1993). One of themost important studies related to this subject focused on the extraction of various natural aromatic raw materials through different procedures, namely, solid/liquid extraction and solid/scCO2 extraction (Pellerin 2003). One of the reported advantages of the use of CO2 is that the amount of scCO2 needed is relatively small and typically in the same order as the amount of rawmaterial whereas the amount of conventional solvent needed are values from 3 (continuous reactor) (Aresta 2010) up to between 10 and 20 (batch reactor) (Marriot, Jessop, and Barnes 2014) times the amount of raw material. In addition, the elimination of waste with the use of conventional solvents cost up to € 380 per ton of waste (Marriot, Jessop and Barnes, 2014), while in the case of CO2, if the waste has not been in contact with organic solvents, it can be re-used for other purposes. Finally, it was estimated that the equipment cost would be higher using CO2 rather than conventional process, but, due to energy savings, environmental safety, and impact parameters, the use of scCO2 was a better option in this comparison. The presence of scCO2 in reactions with gaseous reagentsmakes it possible to operate in single-phase conditions, thus increasing the kinetics ofmass transfer. This is due to the fact that the existing gas-liquid interface when using liquid solvents is avoided and the supercritical media have properties that favor the matter transport (Aresta 2010). The reactions where the use of scCO2 has been most developed are hydroformylation, hydrogenation, oxidation, biocatalysis, and polymers synthesis (Aresta 2010) Hydroformylation in CO2 Hydroformylation is an industrial process of great importance in the manufacturing of aldehydes, obtained from olefins and syngas. This process involves the addition of CO and H2 to a carbon-carbon double bond, forming the aldehyde that contains a number of carbons greater than the starting olefin. Hydroformylation can be carried out by both homogeneous and heterogeneous catalysis, the latter being easy to recycle (Bektesevic et al. 2006). Most investigations on the hydroformylation of olefins or alkenes in scCO2 have been carried out in homogeneous catalytic systems, where the solvent is used to recover the catalyst after the reaction, what involves a great effort and a significant expense when traditional solvents are used. The results obtained with highmolecular weight olefins have been quite satisfactory (85% yield) since these cannot be hydroformylated in aqueous bases with rhodium catalyst due to their low solubility in water (Aresta 2010; Bektesevic et al. 2006; Marriott, Jessop, and Barnes 2014). Hydrogenation in CO2 Hydrogenation in scCO2 is one of the few processes that have been successfully developed on an industrial scale, taking place in both fluid and gaseous phases. While the biphasic hydrogenation reactions use a homogeneous catalyst, the three-phase ones use a heterogeneous catalyst in addition to the reactive liquid and hydrogen gas. Some hydrogenation reactions in scCO2 are listed in Table 2. It can be seen that the main advantages of using scCO2 are the high yields and selectivity obtained in the different hydrogenation reactions. Other studies have been conducted in which the use of CO2 as a solvent favors hydrogenation. For example, in the hydrogenation of nitrile to primary amines, undesired dialkylamines are usually generated, but in expanded CO2 media, the primary amines are stabilized through a reaction easily reversible with CO2, obtaining carbamate salts. On the other hand, the hydrogenation of the oleic acid catalyzed by platinum at 35°C stops at a conversion of 90% even with long reaction times of more than 25 h. However, at the conditions of 55 bar of expanded CO2, the reaction achieves a 97% conversion after only one hour (An et al. 2009; Anastas and Zimmerman 2013; Devetta et al. 1997; Marriott, Jessop, and Barnes 2014; Mayadevi 2012; Wang et al. 2018). 45 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1407 Table 2. Hydrogenation reactions in scCO2. Modified from Mayadevi (2012). Reaction Catalyst scCO2 Advantage Biphenyl Hydrogenation Rh/C, Ru/C Yield > 99% Furfural Hydrogenation Pd/C Switchable selectivity of 5 different products varying the operating conditions 2-butylene-1,4-diol 5% mass Pd/C 100% selectivity for butane-5,6-diol Hydrogenation Styrene oxide to 2-phenyl- Pd/Cu encapsulated with 100% selectivity and yield ethanol polyurea Oxidation in CO2 Another reaction that has been the target of several investigations, is the selective oxidation of organic substrates in dense CO2. One of the key aspects that CO2 presents as a good solvent for this type of reaction is that it cannot be oxidized. This means that it will not lead to the formation of byproducts or unwanted compounds while generating a solvent consumption that would have to be replaced which is the case for most organic solvents (Aresta 2010; Marriott, Jessop, and Barnes 2014). Some of the most recent studies (Ribeiro et al. 2017a; Sutradhar et al. 2017) have analyzed the results obtained from the oxidation of cyclohexane using different catalytic complexes in different solvents. For example, comparing the action of molybdenum complexes in acetonitrile, ionic liquid, and scCO2 has concluded that cyclohexanol has the highest selectivity in scCO2 (98%) (Sutradhar et al. 2017). However, using Fe (II) scorpionate complexes, the highest selectivity of the cyclohex- anone was given for a mixed solvent medium of scCO2 and an ionic liquid ([bmim] [PF6]), reaching values up to 96%, while the maximum obtained in pure solvents was 77% (Ribeiro et al. 2017b). The partial oxidation of alcohols to obtain carbonyls or carboxylic compounds are of high industrial interest. Thus, scCO2 was investigated as a reaction medium for the partial oxidation of aliphatic, unsaturated, aromatic, and benzylic acids with different catalytic systems based on noble metals, both in continuous and discontinuous reactors. The results obtained using palladium and gold catalysts for the oxidation of benzyl alcohol to benzaldehyde were very promising, achieving selectivities greater than 90% (Aresta 2010; Hou, Theyssen, and Leitner 2007; Wang et al. 2014). Biocatalysis in CO2 Another field in which scCO2 can be used as a solvent is biocatalysis. The capability of being adjusted in its properties and its previously mentioned characteristics make the scCO2 especially suitable for use in organic synthesis. The attractive idea of combining natural catalysts such as enzymes with a natural solvent such as CO2 has been an incentive for research in this field, since it seems to be the perfect union between a highly selective and active sustainable catalytic system, and an ecological solvent with excellent transport properties. Thus, scCO2 is presented as an alternative solvent for biocatalysis under non- aqueous conditions, which allows an easy recovery of the products and the enzyme, in addition to providing a similar yield to that observed in organic solvents such as n-hexane and cyclohexane. Although theoretically, this technology seems to have a high potential, the use of biocatalysts in scCO2 has tried to be avoided due to the interactions between the solvent and the catalyst, which lead to the generation of carbamates (Du et al. 2008; Marriott, Jessop, and Barnes 2014; Matsuda 2013). Polymers synthesis in CO2 ScCO2 is the main candidate to replace traditional solvents in the synthesis of polymers due to its environmental advantages that have been exposed previously. However, the use of scCO2 as a solvent in polymerization reactions has a drawback, since high molecular weight compounds, especially polymers, are generally poorly soluble in scCO2 under relatively soft conditions (T< 373 K, P< 35 MPa) (Boyère, Jérôme, and Debuigne 2014; Jo et al. 2017; Vert et al. 2009; Zhang et al. 2015a). Polytetrafluoroethylene (PTFE) was synthesized in a heterogeneous CO2 medium, using a water- soluble persulfate initiator, achieving rapid polymerization kinetics, yield values of up to 90% and 46 #cyclesofcirculation 1408 F. M. BAENA-MORENO ET AL. high molecular weight. PTFE was also produced in a medium based on dry scCO2, both in the absence and in the presence of stabilizers, obtaining morphology of fibrillated PTFE, which could be particularly interesting for the manufacture of hydrophobic microporous membranes without solvents (Giaconia et al. 2008; Romack, DeSimone, and Treat 1995). Chemicals from CO2 As can be seen below, CO2 could also be employed to produce chemicals. This can be achieved through carboxylation reactions where CO2 plays a fundamental role as a precursor for organic compounds. Carboxylation of organic substrates with CO2 The reaction of CO2 with organic substances can lead to the formation of carbon-carbon bonds for the production of carboxylic acids or the formation of carbon-heteroatom bonds for the production of carbonates or carbamates in which the first type is called carboxylation reaction (Senboku and Katayama 2017; Yuan et al. 2017; Zhang andHou 2017). Carboxylic acids are organic compounds in which a carbon atom is linked to an oxygen atom by a double bond and a hydroxyl group by a single bond, forming the carboxyl group (-COOH). They are widely used in food, chemical, and pharmaceutical industries. Its applications include the production of detergents, pharmaceuticals, antibacterials, plastics, dyes, textiles, perfumes, and animal feed. Currently, other advanced applications of carboxylic acids can be found, such as in the production of biopolymers, being additives for lubricating oils, in drug administration, and in tissue engineering. Most carboxylic acids are produced on an industrial scale by chemical synthesis (Djas and Henczka 2018). The synthesis of aromatic hydroxycarboxylic acids with CO2 turns out to be one of the most studied industrial syntheses. Since the carboxylation reaction of Kolbe-Schmitt is the tradi- tionally used process, it is also currently a standard commercial method for the preparation of said aromatic acids (Lindsey and Jeskey 1957). Subsequently, this sparked research into variations of this reaction such as Iijima and Yamaguchi (2008a). They carried out several studies proposing different promoters of the reaction to obtain salicylic acid from phenol and scCO2. In the first place, the direct synthesis of hydroxybenzoic acid (HBA) was carried out under optimal conditions, at 473 K and 8 MPa of CO2, using several types of basic metal oxides as catalysts, such as γ-alumina, zirconia, and ceria. They were also tested with Lewis acids such as SiO2 and ZrO-SO 2- 4 which were identified to be ineffective catalysts for the reaction. Other basic oxides such as CaO and MgO were equally unsuitable for this type of reaction. When investigating the effect of various carbonates of alkali and alkaline earth metals on the synthesis of this acid, it was observed that the catalytic activity of K2CO3 was the highest among the catalysts studied, followed by that of KHCO3, having yields of 36% and 17%, respectively. Table 3 represents an extract of the results produced in two studies for HBA obtaining. As can be seen in Table 3, except for K2CO3, none of the catalysts result in the formation of 4-hydroxybenzoic acid (p-HBA). An increase in salicylic acid formation was observed up to a yield of 68% with the use of 30 mmol of K2CO3, although an optimum amount of K2CO3 of 10 mmol was Table 3. Extract of results obtained for the two studies on the direct synthesis of HBA (Iijima and Yamaguchi 2008b, 2008a). Catalyst Yield (% mol) o-HBA yield (% mol) p-HBA yield (% mol) o- HBA selectivity (%) Study: Direct synthesis of salicylic acid from phenol and supercritical CO2 with K2CO3 as a catalyst (Iijima and Yamaguchi 2008b) K2CO3 36.57 36.02 0.55 98.5 Rb2CO3 0.54 0.54 0.00 100.0 CaCO3 0.39 0.39 0.00 100.0 KHCO3 17.06 17.06 0.00 100.0 Study: Effective regioselective carboxylation of phenol to salicylic acid with supercritical CO2 in the presence of aluminum bromide (Iijima and Yamaguchi 2008a) ZnCl2 5.20 5.20 0.00 100.0 ZnBr2 12.90 12.90 0.00 100.0 AlCl3 2.70 2.70 0.00 100.0 AlBr3 55.90 55.90 0.00 100.0 47 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1409 suggested, since the greatest increase in HBA formation occurs at this amount (Iijima and Yamaguchi 2008b). Although the traditional method previously explained has been widely used, some of the pioneer- ing studies in the synthesis of carboxylic acids are taking place in the field of electrochemistry. One of the advantages of the organic compounds reduction in presence of CO2 is the efficient fixation of CO2 to organic molecules, forming C-C bonds under soft conditions. CO2 electroreduction could be presented as a worthy alternative to these processes that involve intensive use of energy as well as the replacement of toxic reducing agents by electrons. It has been shown that the resulting carboxylic acid is obtainedwith high efficiency by using reactive metals such as magnesium or aluminum galvanic or sacrificial anode, which also has its drawbacks, which will be discussed later (Matthessen et al. 2014; Senboku and Katayama 2017). Some authors studied the electrolysis by divergent pairs of diacid precursors and diol, from the cathodic carboxylation and the simultaneous anodic acetoxylation of conjugated dienes (Matthessen et al. 2015, 2014; Senboku et al. 2015; Tateno et al. 2015). In their studies, an innovative methodology is defined that allows a conversion of CO2 using a durable and inert anode. This process results in the formation of dicarboxylate salts and diacetate esters, from cathodic carboxylation and anodic acetoxylation, respectively. Trifluoroacetate (TFA) and tetraethylammonium (TEA) were used both as supporting electrolytes and as reagents for acetoxylation, forming their corresponding salts in the solution. The electrolysis of other diene substrates was also carried out under the same conditions as in the previous case. It should be mentioned that in the case of 1,3-butadiene, the CO2 pressure was 10 bar. It can be observed that by carrying out the electrolysis of 1,3-cyclohexadiene with nickel cathode and graphite anode, in a solution of CH3CN with TEA and TFA, under a pressure of 1 bar of CO2, a carboxylation yield of 35% and an acetoxylation yield of 49% were obtained (Matthessen et al. 2015). Another application of electrochemistry is ionic liquids. Since the compatibility of ionic liquids with scCO2 is known, they have been frequently used in the electrochemical carboxylation of both supporting electrolyte and reaction medium. One of the examples reported consisted in the electro- carboxylation of a wide range of halogenated aromatic hydrocarbons, such as bromobenzene, iodobenzene, or chloronaphthalene, using a platinum cathode and a magnesium anode in the ionic liquid DEME-TFSI reacting with scCO2. Moderate yields of approximately 50% were obtained, which leaves a considerable range for improvement in these processes. In spite of the obtained yields, it turns out to be an alternative more respectful towards the environment and simpler in terms of being able to purify the products by means of simple column chromatography. Therefore, it is a field still under study (Kathiresan and Velayutham 2015; Senboku and Katayama 2017; Tommasi and Sorrentino 2009, 2006, Zhao et al. 2014). It is concluded that the use of CO2 in carboxylation processes is interesting to meet the economic and environmental requirements, and provides an alternative to traditional CO2 coupling reactions that require organometallic reagents, with a great future of electrocarboxylation, and especially, that is free of sacrificial anodes (Luo and Larrosa 2017; Senboku and Katayama 2017). Carbamic acids from CO2 CO2 has a particular affinity for interacting with various nitrogen nucleophiles, such as ammonia or amines. This fact is of great synthetic relevance since it is a key step towards the carbonylation of the said nucleophile and the synthesis of N-carbonyl compounds. The fixation of CO2 by amines can produce carbamic acids, carriers of the carbamate group (RR’NCO2). Nowadays, the interest in the reaction between amines and CO2 continues, since in addition to its traditional uses, such as in the Solvay process or in the synthesis of urea from ammonia and CO2, new applications with synthetic relevance have emerged, such as the synthesis of esters from carbamates, isocyanates, and ureas (Quaranta and Aresta 2010). Carbamates. The carbamate esters (urethanes) are fundamental structural elements for the develop- ment and obtaining of therapeutic agents, such as drugs or agrochemicals (Vessally et al. 2018). One of the most important methodologies for the preparation of organic acyclic carbamates from CO2 involves the reaction of three components: amines, alkyl halides, and CO2. Firstly, the tri- 48 #cyclesofcirculation 1410 F. M. BAENA-MORENO ET AL. component reaction of amines with alkyl halides and CO2 is a highly known synthetic route for the synthesis of acyclic carbamates, being the object of several investigations. Salvatore et al. have proved the treatment of several aliphatic, aromatic, and heteroaromatic amines with alkyl halides in the presence of Cs2CO3 as a base, tetrabutylammonium iodide as an additive, and Dimethylformamide (DMF) as a solvent, under a CO2 atmosphere, obtaining the corresponding carbamates with yields of up to 98%. This same research group extended its methodology with the use of benzyl chloride, observing reasonable results, with yields from 60% to 96% (An et al. 2014; Salvatore et al. 2002, 2001). Hooker et al. (2009) demonstrated that 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) can efficiently catalyze the carboxylate coupling of amines with alkyl halides and CO2. Various radio-labeled carbamates were obtained by the treatment of [11C] CO2 with a mixture of amines and alkyl chlorides in the presence of DBU as a base, in DMF. The reactions were carried out with amine, alkyl chloride, and DBU at a concentration of 100 mM each, in 300 ml of DMF, with yields from 60% to 77%. Kong et al. (2011) have demonstrated that a range of carbamate esters can be obtained from the reaction of the corresponding aliphatic and aromatic amines with a variety of alkyl and CO2 halides in very soft conditions, at atmospheric pressure of CO2 and at room temperature, using K2CO3 as a base in polyethylene glycol 400 (PEG 400) as solvent and catalyst while considering a more ecological procedure for the production of organic carbamates. The obtained yields from this process varied from 29% to 93%. Xiong et al. (2015) developed a methodology for obtaining O-aryl carbamates from the reaction between aliphatic amine, diaryliodonium salts, and CO2. Under the right conditions, the reaction was carried out for a wide variety of functional groups on the aryl ring of the diaryliodonium salts, such as fluorine, chlorine, bromine, and nitrile. The yields obtained were 63%, 38%, 20%, and 75%, respectively. With asymmetric salts of aryl-(phenyl)-iodonium as functional groups, yields of up to 91% were reported. More recently, Riemer et al. (2016) were able to synthesize different amino acids protected with carboxybenzyl (Cbz) from amino acids with benzyl bromide and CO2 at atmospheric pressure, using Cs2CO3 as a base in Dimethyl sulfoxide (DMSO). The reaction provided the carba- mates corresponding to the said amino acids in favorable yields, between 70% and 90%. Yang et al. (2017) developed a generation of aniline carbamates with nitrile, reacting aniline with 2-ethylbenzo- nitrile bromides and CO2 under soft basic conditions, obtaining yields of 80–86%. New substituents were obtained that turned out to be excellent guiding groups for the activation of anilines with C-H meta-bonds for the construction of new C-C and C-O bonds in metal-catalyzed reactions. There are also studies on the synthesis of carbamate esters promoted electrochemically (Feroci et al. 2003, 2007). Some of the conclusions were that the aliphatic amines gave better yields than the aromatic amines and that the secondary aliphatic amines are more reactive than the primary amines. Thus, it is concluded that carboxylate coupling of amines with alkyl halides and CO2 is one of themost useful synthetic routes for the biologically and synthetically most important carbamate esters. The key features of this procedure are that the raw materials turn out to be cheap and easily accessible, non-toxic byproducts, reasonable yields, and their production from common bases under very soft operating conditions. These results clearly show the possible application of this chemical fixation of CO2 at an industrial level. Despite this, the number of studies reported on this subject continues to be limited, making this field of research still open. Isocyanates. The second key point of this section is the isocyanates, carriers of the RNCO group. Isocyanates are compounds of great industrial importance, since their application reaches various fields. They are used as raw material for the manufacture of phytosanitary agents, pesticides, dyes, resins and plastics, textile waterproofing agents, detergents, bleaches, and adhesives (Germain et al. 2016; Quaranta and Aresta 2010; Wang, Liu, and Deng 2017). One of the phosgene-free alternatives for the synthesis of isocyanates consists of two steps: first, a catalytic synthesis of carbamates from nitrile or amino compounds and CO2, followed by a thermal cracking that provides the correspond- ing isocyanates. There is no chloride involved in this specific route, leading to the simplification of the separation and purification operations, hence increasing the quality of the products. Despite its apparent advantages, few studies were reported on the direct synthesis of isocyanates from CO2, amines, and alcohols (Wang, Liu, and Deng 2017). 49 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1411 Table 4. Summary of studies on the synthesis of carbamates to obtain isocyanates from CO2 (Ammar et al. 2017; Choi et al. 2002; Wang, Liu, and Deng 2017; Yan et al. 2011). Catalyst Operating Conditions Yield (%) Bu2SnO 200 ºC, 24 h, 30 MPa CO2 14 Bu2SnO Me2C(OEt)2, 200 ºC, 24 h, 30 MPa CO2 84 Ni(OAc)2-bipiridina 200 ºC, 24 h, 30 MPa CO2 67 Cs2CO3 200 ºC, 24 h, 2.5 MPa CO2 44 CeO2 150 ºC, 12 h, 5 MPa CO2 91 MnOx(0,03)-CeO2 150 ºC, 12 h, 5 MPa CO2 82 The synthesis of carbamates by reacting CO2, amines, and alcohols were tested in Abla, Choi, and Sakakura (2004)’s work. Initially, they used tin-based catalysts at pressures of 30 MPa of CO2 and 200°C. After 24 h of reaction, the conversion of n-butylamine was only 16%, which could be improved to 100% using acetal in large excess as a dehydrating agent. Due to the toxicity of tin, they used nickel-based catalysts, less harmful and more active, but this methodology was unsatisfac- tory by industrial standards (Abla, Choi, and Sakakura 2001, 2004). Honda et al. (2011) used commercial CeO2 as a heterogeneous catalyst to synthesize methyl benzyl carbamate in one step from CO2, benzylamine, and methanol. Under a pressure and temperature of CO2 of 5 MPa and 150°C, after 12 h of reaction, a greater conversion of 99% of benzylamide was obtained, with the selectivity of the methyl-benzylcarbamate of 92%, obtained without using dehydrating agents. In addition, it had the advantage that the catalyst could be reused after calcination at 600°C for 3 h. More recently, a catalyst of cerium and manganese (MnOx-CeO2) was prepared, which showed high activity in the synthesis of aliphatic carbamates from CO2, aliphatic amines and methanol, reaching carbamate yields of up to 82% and the catalyst can be reused up to four times for a simple recycling process (Zhang et al. 2015a). Although there have been several studies conducted in recent years regarding the use of CO2 for the synthesis of isocyanates which are also summarized in Table 4, most are still in pilot scale (Wang, Liu, and Deng 2017). Undoubtedly, phosgene is the most effective carbonylation agent and its technology is too established to be replaced, due to its high efficiency and profitability. Even so, its environmental and health risk makes it increasingly necessary to search for alternative routes for the synthesis of phosgene-free isocyanates. The key to finding the methodology that increases the performance of isocyanates lies in three points. Firstly, choose a suitable carbonyl source, for example, CO2; although it represents a great challenge. Secondly, develop an efficient catalytic system and finally, search for an integrated production system that takes advantage of the resources used. Ureas. In this section, the manufacturing of urea from CO2 will be looked into. The synthesis of urea is currently the main consumer of CO2 in organic synthesis. Urea, (CO(NH2)2), is the most widely produced nitrogen fertilizer and is commonly marketed. It is produced at industrial level via the reaction of ammonia with CO2, a two-stage process where ammonia and CO2 react to form ammonium carbamate, which is then dehydrated producing urea. This industrial method is based on the Bosch-Meiser urea process, developed in 1922. This reaction is exothermic and the process requires operating conditions between 150°C and 250°C with pressures of 5–25 MPa (Wang, Xin, and Li 2017; Xiang et al. 2012). The apparent need to employ high pressure and temperature is what led Xiang et al. (2012) to investigate a way based on a negative corona discharge. They demonstrated for the first time that, although the reduction of CO2 by NH3 in urea at environmental conditions was not feasible through conventional processes, bymaking these gases available under said discharge urea could be synthesized at room temperature and pressure. Thus, without using any metallic catalyst, they achieved a conversion of 82% under a pressure of 1 atm and at 20°C. They observed that the yields of the solid mixture of urea and ammonium carbamate increased with the reduction of temperature and with the increase of the molar ratio NH3/CO2 and the frequency of discharge. Recently, the use of metal salts of oxalates as catalysts for 50 #cyclesofcirculation 1412 F. M. BAENA-MORENO ET AL. the synthesis of N, N’-dialkylureas fromCO2 and amines was described (Sun et al. 2016). They compared the use of metal salts of sodium oxalates, nickel, manganese, iodine, cesium, and zirconium, in addition to other salts of yttrium of borate, carbonate and citrate, and yttrium oxide, resulting in Y2(C2O4)3 being the catalyst that provided higher yields. Under the optimal conditions, which were found to be 20 atm of CO2, 10 atm ofNH3 and at a temperature of 150°C, in N-methyl-2-pyrrolidone (NMP), high conversions of 71–86% were obtained. However, the secondary amines and aromatics showed to be incompatible with this carbonylation reaction. In addition to the target product, byproducts were also formed: N, N’- dialkyloxamide, N-alkynylcyanate, and N-N’-dialkyl carbodiimide. A recent method for the production of ureas in which primary amines and CO2 were used in the absence of additives and solvents was described. Research on temperature and pressure revealed that there is a point of equilibrium of both factors. Atmore than 180°C the yield gradually decreased, which could be attributed to the reversibility of the reaction. The inclusion of additional additives in the system did not improve the performance considerably. Under the optimal reaction conditions (180°C and 10 MPa of CO2), the aliphatic primary amines react gently with CO2 to give ureas of different types, with a selectivity of 100% and yields that in some cases reached up to 97% after 24 h of operation (Wu et al. 2010). From the point of view of profitability and green chemistry, the use of a cheap, stable, and recyclable catalyst without a stoichiometric excess of dehydrators in the synthesis of urea is very attractive. This implies that researchers must still look for new concepts and technologies of dehydration for the synthesis of urea, especially based on the new mode of activation for CO2, amines or carbamates so to be able to take them as soon as possible on a large scale. Linear and cyclic carbonates from CO2 Among the various chemical conversion processes that involve the transformation and consumption of CO2, an actively investigated field is the production of organic carbonates, of linear, acyclic, and cyclic type, in addition to their use for the synthesis of polycarbonates. This synthesis of carbonates, which is environmentally friendly, could be an exit from the conventional use of toxic chemicals such as phosgene (COCl2) and carbon monoxide (CO) (Lim, Lee, and Jang 2014; Martín, Fiorani, and Kleij 2015). Acyclic carbonates. In recent decades, the synthesis of CO2 based acyclic carbonates such as dimethyl carbonate (DMC), diethylene carbonate (DEC), and diphenyl carbonate (DPC) has attracted attention in various studies. Especially, the DMC has been one of the most active focuses in this field, since it represents a molecule with a wide variety of applications such as apolar solvent, fuel additive, electrolyte in lithium-ion batteries and carbonylation reagent, methylation, and methoxycarbonylation (Prat et al. 2016; Pyo et al. 2017). More than 90,000 tons of DMC are consumed worldwide annually, being destined to the production of polycarbonates, approximately 50%, and up to 25% of its total use is as a solvent. Traditionally, DMC has been produced from the reaction between methanol and phosgene, a method that has led to disuse being replaced by less toxic routes that involve the oxidative carbonylation of methanol (Garcia-Herrero et al. 2016; Kindermann, Jose, and Kleij 2017). Most acyclic carbonates are synthesized from alcohols and CO2 by heterogeneous catalysis using metal oxides, zeolites, and metal complexes. Although in comparison with many effective homogeneous catalysts, heterogeneous catalysts have the advantage of being superior in stability and reuse. However, they also have deficiencies: the catalytic activity is usually unsatisfactory, so it is necessary to use solvents to improve the activity and selectivity, in addition to require dehydrating or efficient drying to obtain carbonates with high yields (Honda et al. 2014a; Dai et al. 2009). Some of the studies carried out on homogeneous catalytic systems for the formation of DMC from methanol and CO2 investigated the use of titanium, zirconium and nionium compounds, as well as complexes of tin and other organometallic compounds, whose efficiency was quite low (Kizlink and Pastucha 1995). Furthermore, using ortho-esters as a dehydrating agent and [Bu2 Sn(OMe)2] as a catalyst, a yield and selectivity of the DMC of 48% and 85%, respectively, were obtained. This was achieved under high pressures of approximately 300 atm of CO2 and 180°C, 51 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1413 resulting in a problem concerning ortho-esters including difficult recycling (Sakakura et al. 2000). The use of acetal as a drying agent was also studied, since it was considered more sustainable when regenerating, achieving higher yields in DMC (58%) in the presence of the tin catalyst (Sakakura et al. 1999). Organic desiccants were also used, which made zeolites, considered inefficient at high temperatures, achieved yields of up to 45% in DMC from methanol (Choi et al. 2002). Despite the different options studied, significant advances were achieved only with the addition of desiccant or dehydrating agents. The use of nitriles, compounds capable of regeneration through the formation of amides and subsequent conversion to nitriles, was proposed. The results were not expected when using acetonitrile as a desiccant for the synthesis of DMC from methanol and CO2 with CeO2 as a catalyst, since at 0.5 MPa of CO2 and 150°C, the yield of DMC after 48 h reached only 9%, with a selectivity of 65%. Improved results were obtained when using benzonitrile, increasing the yield and selectivity of the DMC up to values of 47% and 75%, respectively, after 86 h of operation under a pressure of 1 MPa and at 150°C (Honda et al. 2011). After making a classification of different dehydrators based on nitrile, it was concluded that 2-cyanopyridine was the nitrile that produced the best results when used with cerium oxide. The yield (94%) and the selectivity (96%) of the DMC reported in this system after 12 h of reaction at 5 MPa of CO2 and 120°C were surprisingly high. In addition, the use of 2-cyanopyridine as a desiccant had the advantage that its dehydration by Na2O and SiO2 was feasible, although its efficiency could be improved (Honda et al. 2013; Honda et al. 2014b). Due to the excellent results in performance and selectivity registered when combining CeO2 with 2-cyanopyridine, this system appears as a promising candidate for its application in the industrial and commercial field. In 2014, the first continuous flow process with fixed bed reactors was developed by means of this system, represented in Figure 3. Briefly, in this process, a system capable of carrying out reactions from atmospheric pressure to 400 bar was used. Pumps were used both for the feed of the methanol and 2-cyanopyridine mixture and for the supply of liquid CO2, while the CO2 gas was introduced into the system by means of a thermal mass flow controller. In addition, the lines after the reactor were maintained at tempera- tures above 180°C to avoid the formation of solids. Tests at various temperature and pressure conditions were made presented in Table 5. Figure 3. Flowchart of the continuous process for the production of DMC. Adapted from Bansode and Urakawa (2014). 52 #cyclesofcirculation 1414 F. M. BAENA-MORENO ET AL. Table 5. Results of the analysis of the effects of temperature and pressure in the continuous production process of DMC from CO2 and methanol, with 300 mg of catalyst. (Bansode and Urakawa 2014). Study T (°C) P (bar) Methanol Yield (%) DMC Selectivity (%) Pressure Effect 120 1 27 96,5 30 92 >99 >30 92 >99 Temperature Effect 80 200 17 >99 120 92,4 >99 140 94 98 160 90 93 It was concluded that the efficiency of the reaction reached a maximum and remained practically constant from 30 bar of CO2, and that the optimum operating temperature was 120°C, as presented in Table 5. A key finding reached in a previous study was the existence of a delicate balance between temperature, pressure, and residence time required to achieve an excellent catalytic performance leading to the appearance of new opportunities in heterogeneous catalysis that promotes the investigation of the possibility of transforming traditional discontinuity in continuous processes, since batch processes are especially limited by the balance and the presence of water (Bansode and Urakawa 2014). Given its good results, it is not surprising that research has intensified in this field. Alongside this, the reuse of the cerium oxide catalyst has been studied, which is eventually deactivated by adsorption of the amide formed by 2-cyanopyridine. Furthermore, this system is not only limited to the formation of acyclic carbonates, but also for the synthesis of cyclic carbonates, carbamates, cyclic and acyclic urea derivatives, and even for the preparation of polymeric materials from CO2 and diols (Tamura et al. 2016; Honda et al. 2014c). The synthesis of acyclic carbonates free of metals has also been reported through the use of organic promoters. To avoid the problem of dehydration and promote an effective and direct coupling of alcohols and CO2, the Mitsunobu reagent was introduced, through which it was possible to convert primary, secondary, and even tertiary alcohols into acyclic carbonates. The product yields are from 70% to 98% in less than 8 h of operation, working between 90°C and 100°C (Chaturvedi, Mishra, and Mishra 2007). Moreover, the use of DBU was studied for the synthesis of organic carbonates, both acyclic and cyclic. Through this method, moderate performance (48%) was achieved at relatively soft conditions (70°C and 10 bar CO2) for the DMC. In these same conditions, it was possible to obtain a yield of 69% for the synthesis of dibenzyl carbonate, another acyclic carbonate (Lim, Lee, and Jang 2014). Another method reported for the manufacture of DMC is the electrochemical synthesis from methanol, CO2 and propylene oxide in an ionic liquid (bmimBr). Under optimum conditions; temperature of 30°C, atmospheric pressure of CO2, with a molar ratio of methanol/propylene oxide of 11.5:1 and after 48 h of reaction, 97% conversion of methanol as well as the yield of the DMC of 75.5% was obtained (Yan et al. 2011). Cyclic carbonates. The production of cyclic carbonates from CO2 synthesis is a well-established field. One of the most investigated reactions in this field is the addition of CO2 to epoxides which has also been used on an industrial scale for the manufacture of cyclic carbonates and polycarbonates (PC) (Martín, Fiorani, and Kleij 2015). For the reaction of epoxides with CO2, catalysts have been developed based on alkali metal salts, metal oxides, transition metal complexes, organic bases, and ionic liquids. Studies are still emerging that raise other alternative procurement systems, such as, for example, the use of proteins for the catalysis of this reaction. It was demonstrated that amino acids can become a reaction catalyst for cycloaddition of CO2 with epoxides. Relatively adverse conditions, more than 6 MPa of CO2 at 130ºC for 48 h, were necessary to obtain satisfactory results from the use of amino acids (Saptal and Bhanage 2017). Even so, when combining alkaline metal salts with amino acids, excellent results were reported, reaching a propylene oxide conversion of 99% after one hour of operation at a temperature of 120 ºC and 2 MPa of CO2 (Yang et al. 2014). 53 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1415 Table 6. Results of PC synthesis from different catalysts. Modified from Chang et al. (2018). SwithOut WP WITH WP CO-CATALYST PC YIELD (%) CO-CATALYST PC YIELD (%) KI 7 KI 94 KBr 3 KBr 29 KCl Traces KCl 13 DBU 6 DBU 20 DMAP Traces DMAP 15 TBAI 30 TBAI 81 Chang et al. (2018) recently proposed the use of wool powder (WP) as a catalyst for the coupling of epoxides with CO2. By having hydroxyl, carboxyl and sulfonic acid groups, which turn out to be activators of epoxides while amino groups are the activator of the CO2 molecule, it seems to be a good candidate to catalyze this type of reactions. Using CO2 with a purity of 99.99% and propylene oxide as reagents, PC synthesis was studied using WP alone and with other co-catalysts: potassium iodide (KI), potassium bromide (KBr), potassium chloride (KCl), tetrabutylammonium (TBAI), DBU, and N, N-dimethylaminopyridine (DMAP). After 3 h of operation at 120°C and 1.5 MPa of CO2, and without the use of any solvent, the results obtained are shown in Table 6. When WP was exclusively used, PC performance was only 12%, while as can be seen in presented Table 6, using KI had the performance of 7%. Surprisingly, the combination of both in the same reaction gave a yield of 94% of the desired product. The dependency of the yield with the reaction time was studied, observing that it increased rapidly in the first 3 h, reaching its maximum in 94%, practically constant even when the operating time increased (Chang et al. 2018). The direct carbonylation of glycerol and CO2 to obtain glycerol carbonate (GC) is a very interesting and challenging route, since it would involve converting two materials considered as waste into valuable products for the chemical industry (Mohd et al. 2017). One of the most recent studies about the synthesis of GC, deals with the carbonylation of glycerol with CO2 on cerium oxide catalysts, using as a desiccant agent of 2-cyanopyridine. Under optimized operating conditions of 150°C, 4 MPa of CO2, 10 mmol of glycerol, 30 mmol of 2-cyano-ridin and 10 mmol of CeO2 producing GC with the yield of approximately 79% after 5 h of reaction (Liu et al. 2016). Using the same system of CeO2 and 2-cyanopyridine, PC synthesis was developed from propylene glycol (PG). The influence of 2-pridine turned out to be decisive due to the fact that the yield of PC produced went from less than 0.3% to more than 99% by the addition of 100 mmol of 2-cyanopyridine and only one hour of operation, at a temperature of 130 ºC and 5 MPa of CO2 while using 20% molar of catalyst (Honda et al. 2014a). Given the current situation in the field of the synthesis of carbonates, both acyclic and cyclic, certain points can be concluded. One of the crucial characteristics for the optimization of these processes continues to be the regeneration of the desiccant species since, if it can be regenerated efficiently, the process would have a greater potential for its large-scale application and commercial exploitation. On the other hand, although the systems that use organic catalysts are more attractive for the environment, the activity shown by the metal complexes is considerably greater, so it is necessary to continue developing organometallic systems capable of equaling and even exceeding the activity promoted by the catalysts based on metals. As mentioned, the study of catalysts capable of facilitating high conversions of epoxides and alcohols at low CO2 pressures is a field of great interest. It is worth mentioning that the research alongside the different routes reported in the last twenty years about the synthesis of the carbonates has made it possible to use more ecological and sustainable catalytic methods in pharmaceutical production and bulk chemistry. Polymers from CO2: polycarbonates and polyurethanes The use of CO2 to obtain polymers would not imply a substantial reduction in emissions, since the emission from the consumption of fossil energy is several orders of magnitude higher compared to 54 #cyclesofcirculation 1416 F. M. BAENA-MORENO ET AL. the reduction that would be produced through the use of CO2 in this industry. Even so, its use would make this sector meet the requirements of sustainable development through the utilization of versatile raw materials in the synthesis of polymers. It is important to note that the polymers generated from CO2 are biodegradable (Qin and Wang 2010; Trott, Saini, and Williams 2016). Polycarbonates obtained from CO2 and epoxides copolymerization, usually show inferior mechanical properties, in addition to a moderate chemical and thermal stability in comparison with the polycarbonates produced from bisphenol. Although these characteristics limit their industrial appli- cation as plastics, the biodegradability and sustainability of the synthesis of these polymers stimu- lated both the search for new applications and research to improve their properties and the efficiency of their synthesis (Taherimehr and Pescarmona 2014). The most widely studied CO2-based copolymers are propylene polycarbonate (PPC) and cyclo- hexene polycarbonate (PCHC), synthesized from propylene oxide (PO) and cyclohexene oxide (CHO), respectively (Engels et al. 2013). Different investigations have focused on the search for catalysts that increase the efficiency and selectivity of the desired product, as in most fields where the use of CO2 is treated, due to its high stability (Xu, Feng, and Song 2014). Much of the catalytic systems investigated are homogeneous complexes based on metals combined with a nucleophile, which is often an organic salt. Since this reaction produces both cyclic carbonates and polycarbo- nates, the selectivity of these will be determined by the operating conditions, taking into account different factors. On the one hand, depending on the type of epoxide used, the formation of the polymer product will be more or less favored. Obviously, the operating temperature will also have an influence, favoring the high temperatures the synthesis of the cyclic product, since it is the thermo- dynamic product. On the other hand, due to intermolecular reactions, the higher the ratio between the nucleophile and the metal, the greater the selectivity of the cyclic product (Machado, Nunes, and Da Ponte 2018). The homogeneous catalysts can be classified into two types: bicomponent catalysts, which consist of the use of metal (III) complexes with other co-catalysts and dinuclear or bimetallic catalysts, which are metal complexes (II/III). Catalysts of the first type are usually metal complexes of Co (III), Cr (III), Mn (III) or Al (III), coordinated with ligands such as salicilimine or porphyrins. The co-catalysts employed are typically ionic salts, such as bis(triphenylphosphine)iminium chloride (PPNCl) or Lewis bases such as 4-dimethylaminopyridine (DMAP) (Trott, Saini, and Williams 2016). Some of the highest activities in the synthesis of PPC were reported using bifunctional catalysts substituted with ionic groups, reaching a conversion frequency (TOF) of up to 26,000 h−1 with low catalyst loads (ratio [catalyst]/[PO] = 1: 25000) (Na et al. 2009). Lee et al. (2005) were pioneers in the use of a series of complexes of bis(anilido-aldimine) and Zn (III), which showed considerably high activities (TOF = 2860 h−1) with very low catalyst loads (ratio Zn/ Epoxide = 1:50000). Kember et al. (2012) prepared a series of di-cobalt halide catalysts with several neutral co-ligands, such as pyridine, methylimidazole, and DMAP. They were used at a moderate temperature and at 1 atm of CO2 for the synthesis of PCHC from CHO. In many cases, the registered activities were from good to excellent (TOF from 16 to 480 h−1), taking into account the low pressures under which the reaction was executed. Heterogeneous catalysts have also been reported in this area of study, such as zinc glutarate or other carboxylates, and double metal cyanides, highlighting Zn3(CoCN6)2. In some cases, they are used industrially as epoxide homopolymerization catalysts, although for their use in CO2 copoly- merization much stronger conditions are required than for homogeneous catalysts. They need high CO2 pressures and generally produce polyether carbonates instead of polycarbonates (Sebastian and Srinivas 2013; Trott, Saini, and Williams 2016). The disadvantage of this type of catalysts is their implicit toxicity when containing metals, whose use is strictly restricted, as well as the fact that their presence should not be detected in the final biodegradable polymers. It is for this reason that several efforts have been made to achieve metal complexes that are more respectful with the environment, but with high catalytic activity. Some of these metals are Fe, Zn, Mg, and Ti. For example, Wang et al. (2015) designed a binary complex of titanium salts for the synthesis of PCHC, which compared its tetravalent counterpart and increased its activity from 41 to 557 h−1. Although all these systems 55 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1417 showed polymer formation from CO2 and CHO, in the CO2/PO system the corresponding cyclic carbonate is produced and the propylene polycarbonate has a very low activity, this polymer being one of the most used industrial level (Liu and Wang 2017). The synthesis of polyurethane (PU) has been another field of study during the last years. PU currently has multiple applications: elastomer, foam, adhesive, packaging, and sealant. This last generation polymer is synthesized on the basis of the reaction between isocyanates and polyols. Due to the decrease in the price of isocyanate in recent years (less than 2000 $/ton since March 2015) (Liu andWang 2017), the challenge to reduce the cost associated with the synthesis of PU is focused on the price of polyols, which initially were cheap. This is where polyether carbonate polyols or CO2 polyols come into play providing a promising way to lower costs of raw material, which is a substitute for polyols from polyether or polyester. Some of the main advantages have already been analyzed: polyether carbonate polyols with a CO2 content of 20% mass reduce greenhouse gas emissions by 11–19%, with the saving of fossil resources that implies (13–16%) (von der Niklas and Bardow 2014). In addition, the PU synthesized from these polyols presents an improved resistance to oxidation and hydrolysis with respect to that based on polyether polyol (Wang et al. 2016b). Thus, both from the economic and technical point of view, the CO2 polyols are presented as a substituent with great potential of conventional polyols, whose overall production in 2016 was approximately 9.4 Mt. The initiator of the reaction is another important parameter to determine the characteristics of the polyols of synthesized CO2. Thus, when employing oligomeric alcohol initiators, the required copolymerization time will be higher and producing polyols with low average molecular mass (MN) and high content of carbonate units (CU) will be difficult (Trott, Saini, and Williams 2016). To reduce this problem, the use of organic dicarboxylic acids as initiators has begun to be carried out. Using sebacic acid as an initiator, a controlled synthesis of CO2-diol was achieved, with a catalyst activity of 1 kg of polymer/g of catalyst, a controllable MN below 2000 g/mol was achieved, although the content in CU could modify between 40% and 75% (Gao et al. 2012). The CO2-triol was synthesized in a similar way using 1,3,5-benzene tricarboxylic acid (TMA) as an initiator, providing an MN between 1400 and 3800 g/mol and a content of CU somewhat lower than for the CO2-diol (20–54%) (Liu et al. 2014). When the initiator represents approximately 10% of the total weight of the raw material for the copolymerization reaction to take place, its cost must be considered when choosing which initiator to use (Trott, Saini, and Williams 2016). That is why oxalic acid has been selected as the initiator, since it turns out to be the cheapest organic dicarboxylic acid. One of the most recent studies has reported the synthesis of CO2-diol as a flame retardant from the use of bisphenol A as an initiator. The resulting polyol was obtained with a content in CU of 42% and an MN of 2400 g/mol, with a productivity of 2.4 kg of polymer/g of the catalyst after 6 h of operation at 2 MPa of CO2 and 75°C (Ma et al. 2016). Due to the great improvement of the efficiency of these systems, a production line of 10000 tons per year of CO2 polyols have been built in the city of Nantong, Jiangsu province, located in China, carried out by the company Huasheng Polymer Co. On the other hand, Covestro invested up to 17 million dollars for the configuration of a factory of CO2 polyols with a capacity of 5000 tons per year, becoming doubly awarded in 2017 for the use of CO2 for the synthesis of polyurethane foams, generating sustainable material and even reducing the use of fossil raw materials consumed previously by up to 20% (Alex 2015; Covestro 2017). As it has been observed, this field of research is continuously active with much still to be improved however, studies are progressing in the right direction. Another addition to the study of these reactions would be the substitution of reactive epoxides for ones that are bio-derived, and not generated on the basis of fossils. Thus, the production of polycarbonates could be totally renewable. The main drawback is that these bio-derived species are generally highly substituted epoxies, so they are more challenging to present a more complex structure and considerably less reactivity. Mineral carbonation Mineral carbonation will be treated in this section, a chemical process in which CO2 reacts with a metal oxide, such as magnesium, calcium or iron for the formation of stable carbonates such as 56 #cyclesofcirculation 1418 F. M. BAENA-MORENO ET AL. calcite (CaCO3) and magnesite (MgCO3). Both calcite and magnesite are of great interest for their wide variety of applications in the pharmaceutical, cosmetic, explosives, paints, inks, resins, rubber, detergents, construction industries, and in particular, CaCO3 is used for the surface treatment of plastics (Cuéllar-Franca and Azapagic 2015; Gao et al. 2018). The great potential of using this type of processes can be easily understood when analyzing that the amount of carbon in the atmosphere currently involves around 870 Gt (NOAA/ESRL 2017), while approximately 39 million Gt of carbon is present in the carbonated rocks of the earth’s crust, such as marble, limestone or chalk (Abdeen et al. 2016b; Oelkers and Cole 2008). Thus, to generate this reaction of mineral carbonation, the use of silicates based on magnesium seems to be indicated due to its availability in large quantities throughout the world, being the main sources of these natural magnesium silicates the olivine, the forsterite, and the serpentine. In the case of calcium silicates, wollastonite and anortite are usually employed (Oelkers and Cole 2008; Olajire 2013). There are also alternative resources as a source of calcium and to a lesser extent, magnesium which is an industrial alkaline waste. Its main advantages are its availability at low cost, high reactivity compared to that of natural minerals, proximity to CO2 sources, and the possibility of improving environ- mental quality by encapsulating potentially toxic elements. However, these wastes are usually available in smaller quantities than minerals, making their use feasible at the individual plant level only. Some of the alkaline residues studied for use in mineral carbonation since 2008 are shown in Table 7 (Gao et al. 2018; Olajire 2013). Wastes with the highest CaO/MgO content were ashes from coal-fired power plants and stainless steel slag, due to the industrial process from which they come. This carbonation process can be carried out ex situ in a chemical processing plant after the extraction and processing of the silicates or in situ, by injecting CO2 directly into geological formations rich in silicates or alkaline aquifers (Olajire 2013). When dealing with this project of using CO2 to obtain useful chemical products, only ex situ carbonation will be developed (Figure 4) (Mazzotti et al. 2005). As can be observed in Figure 4, in ex-situ mineral carbonation the CO2 generated is sent to a mineral carbonation plant, where resulted carbonated compounds are stored for its re-use or final disposal. The routes of the mineral carbonation process are a combination of the treatment of minerals and the CO2 capture in them. The pretreatment usually consists of the extraction, crushing, and grinding of minerals before carbonation. The main objective of these actions is to increase the reactive surface, thus increasing the reaction rate of carbonation. Thus, mineral carbonation methods can be divided into direct and indirect (Helwani et al. 2016). In the direct methods the mineral is carbonated in a single step, while in the indirect, the reactive metal oxides are first extracted from the ore matrix to be carbonated in a later step, obtaining in this way high purity carbonates (IPCC 2005; Mazzotti et al. 2005; Olajire 2013). Within the direct routes, initially, the gas-solid route can be found, where gaseous CO2 directly affects the mineral or alkaline solids. This method is simple, but the reaction rates were very low, that is why its development has not continued. There is also direct aqueous carbonation, which involves three phases coexisting in a single reactor. Firstly, the CO2 dissolves in an aqueous solution obtaining a slightly acidic medium with HCO3. On the other hand, there are the leachates of Ca or Mg from the mineral matrix that, together with the solution, cause the carbonate to precipitate. A lot of studies have been developed in this area (Baciocchi et al. 2013, 2011; Lombardi et al. 2012, 2011; Olajire 2013). Regarding indirect routes, there have been many proposed methods with different minerals. First of all, the multistage gas-solid method stands out. In this method, the Ca/Mg silicates are converted into hydroxides or oxides (Ca/Mg(OH)2 and Ca/ MgO) which will be transformed into the corresponding carbonates by its dry carbonation with CO2 (Wang et al. 2017). Regarding the carbonation of minerals, despite being thermodynamically favorable, it is not easy to carry on an industrial scale. The main challenges to be faced in this type of reactions lie in the gigantic scale needed to reduce real CO2 emissions and be able to carry out this mineralization, in addition to the need to accelerate the formation of carbonate to make it more efficient. The question whether this process would significantly affect the reduction of emis- sions has to take into account two opposite aspects: treatments such as transport, heating or cooling 57 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1419 Table 7. Industrial waste suitable for mineral carbonation (Gao et al. 2018; Olajire 2013). INDUSTRIAL WASTE CaO – MgO PRESENCE Ashes from coal-fired power plants 65% mass CaO Bottom ash from solid waste incinerators 20% mass CaO Fly ash from solid waste incinerators 35% mass CaO Paper recycling ash 35% mass CaO Stainless steel slag 65% mass CaO+ MgO Figure 4. Ex situ mineral carbonation process. Adapted from Mazzotti et al. (2005). of CO2 would not be entirely necessary, since carbonation would take place around the emitting plant of this gas. On the other hand, the extraction, transport, and preparation of minerals also consume energy, but this is something that could be solved with the use of alternative raw materials such as wastes from different industries. Thus, the main advantage of mineral carbonation is the formation of stable carbonates capable of storing CO2 for long periods of time, without the risk of leakage as in other CCS. Due to these qualities, it is presented as one of the most interesting and favorable technologies for the reduction of CO2 emissions on a large scale. Fuels from CO2 Converting CO2 into fuels generally requires a reforming reaction, typically, hydrocarbon and carbon reforming reactions and hydrogen reforming reactions (hydrogenation) (Jiang et al. 2010; Styring et al. 2011). The main processes to obtain fuels from CO2 are syngas from reforming of CH4, gas hydrates, and biofuels from microalgae. CO2 reforming of CH4 Three different processes have been proposed to obtain syngas via reforming of methane used for the synthesis of syngas: steam reforming (SRM), partial oxidation (PO) and dry reforming (DRM). The SRM is the conventional technology used for the production of hydrogen from hydrocarbon fuels 58 #cyclesofcirculation 1420 F. M. BAENA-MORENO ET AL. (Abdullah, Ghani, and Vo 2017). Approximately 75% of the hydrogen produced is obtained by this process, due to its higher performance compared to the other two alternatives (Fan et al. 2016). The differences among SRM, PO, and DRM for syngas production are based on the kinetics and energy of reaction, the ratio of synthesis gas produced (H2/CO) and the used oxidant: water in SRM (1), oxygen in PO (2) and CO2 in DRM (3) (Abdullah, Ghani, and Vo 2017; Ebrahimi, Sarrafi, and Tahmooresi 2017). Thus, of all these technologies, DRM is the most promising since it uses two abundant greenhouse gases for the manufacture of a useful product and of great importance in the industry, at the same time that it is presented as a possible method to reduce the net emission of these gases into the environment (Selvarajah et al. 2016). This process is also more economical than others, since it CH4 þ H2O ! COþ 3 " H2 ΔH298K ¼ þ228kJ=mol (1) CH 14 þ 2 " O2 ! COþ 2 " H2 ΔH298K ¼ $22; 6kJ=mol (2) CH4 þ CO2 ! 2 " COþ 2 " H2 ΔH298K ¼ þ247kJ=mol (3) eliminates the gas separation process of the final products. Additionally, biogas (CO2, CO, and CH4) can be reformed through this process and the synthesis gas product is even considered as a storage of solar and nuclear energy. The use of catalysts in the dry methane reforming process is of great importance to maximize the production of syngas by altering and improving the reaction rate. Being an endothermic reaction, high temperatures are required to be carried out effectively, which can be lowered due to the presence of catalysts (Aramouni et al. 2018; Egawa 2018). Among the numerous possible materials to be used as catalysts for CH4 reforming with CO2, it has been found that the catalysts supported by noble metals show a promising performance in terms of conversion and selectivity towards the synthesis gas. Particularly Ru, Rh, and Ni are classified as active metals. Most of the catalysts used in this synthesis are based on nickel, which has reported long-term deactivation problem due to the deposition of coke, causing the conversion of reagents to decrease (Abdullah, Ghani, and Vo 2017; Aramouni et al. 2018; Egawa 2018). Several authors concluded that the main and desired reaction of the dry reformate is favored thermodynamically at temperatures above 730°C, although to achieve an H2/CO = 1:1 mixture ratio of the synthesis gas obtained with a minimum formation of coke and a CO2/CH4 feed-rate of the unit, temperatures higher than 900 ºC are required (Abdullah, Ghani, and Vo 2017; Egawa 2018; Nikoo and Amin 2011; Selvarajah et al. 2016). At this high temperature, secondary reactions responsible for the formation of coke were not favored, except for the decomposition of methane to be endothermic. Thus, the maximum carbon formation usually occurs at temperatures between 100 and 300 ºC, which is favored by a CO2/CH4 ratio greater than unity, due to the presence of H2 (Aramouni et al. 2018). Recently, Hassani et al. conducted a study where they showed, among other effects, the H2/CO ratios produced in the DRM reaction at different temperatures under a pressure of 1 atm, using a Ni/Al2O3 nanocatalyst and with a CO2/CH4 = feed ratio of 1. They observed that as the temperature increased, the H2/CO ratio increased with it, which is due to the endothermic nature. Under the conditions specified to obtain an H2/CO ratio of the unit in the synthesis gas produced, temperatures higher than 850 ºC were necessary, thus giving the greatest conversion of reagents and the best performance (Hassani et al. 2016). Another very recent study analyzed the activity and selectivity of Ni catalysts with natural clay base for the DRM reaction. The effectiveness of catalysts with natural clay support (Al2O3 · 2SiO2 · 2H2O), clay modified with Fe and clay modified with Cu were checked. The methane and CO2 conversions recorded were greater than 75% at temperatures above 800°C for 59 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1421 all catalysts, except for the clay modified with Fe, which reached a maximum conversion at this temperature of 50% and 55% for CH4 and CO2, respectively (Liu et al. 2018a). Despite its great environmental potential, DRM is not considered an industrially mature process. The extremely high endothermic reaction requires a lot of energy, along with the rapid carbon formation that ultimately leads to the deactivation of the catalyst, long reaction time, and the requirement of pure CO2. These disadvantages make the DRM an impractical process that still needs additional developments. Future research in this field will probably revolve around catalysts based on bimetallic nickel like the Co-Ni catalyst. This is due to the fact that these catalysts have shown stable activity and high resistance to deactivation, even though carbon deposition is gener- ated. The combined reforming reactions, such as DRM and partial oxidation, should also be considered and studied in greater depth, since the heat released by partial oxidation may be the heat supplied for DRM, which may lead to minimizing the operating cost. Gas hydrates from CO2 Gas hydrates are non-stoichiometric crystalline forms of water that are filled with small-sized gas molecules in its molecular cavities via hydrogen bonding at low temperatures and high pressures. Among the gases that could form a hydrate compound (methane, ethane, carbon dioxide, and nitrogen), CH4 hydrates are expected to be an important energy resource in the near future, due to the fact that it is estimated that there are about 20,000 trillion m3 of CH4 hydrate below the ocean, which is more than all of the current fuel sources combined (Collett 2002; Pan et al. 2018). Many researchers in the past decades have studied the recovery of CH4 hydrate from the ocean floor at various conditions (Fujioka et al. 2003; Collett 2002; Pan et al. 2018; Liu et al. 2018a), and more recently the idea of the replacement of CH4 in the hydrate with high-pressure CO2 emerges as a long-term storage of this gas and a way to keep the ocean floor stabilized after recovering CH4 gas (Ota et al. 2005). Also, the direct use of CO2 hydrate in oil production pipelines has been reported by some authors, as well as CO2 hydrate-technology which is growing in relative to transportation processes (Jiang et al. 2016; Sabil, Azmi, and Mukhtar 2011; Veluswamy et al. 2018; Yu et al. 2008). The advantages of CO2 hydrate as a way of capturing are numerous. Firstly, the main chemical compound needed for CO2 formation is water, which makes the process cheap and green since a solvent such as MEA or sodium hydroxide is not required. Secondly, it has been studied that the reduction of energy requirements for hydrate formation is possible by employing some chemicals in low concentrations (Liu et al. 2018b; Mooijer-Van Den Heuvel, Witteman, and Peters 2001). Among their uses, the feasibility of seawater desalination via hydrates was developed industrially and demonstrated that could be economically beneficial with the use of a promoter (Englezos 1993; Javanmardi and Moshfeghian 2003). Studies have been conducted where the feasibility of employing eutectic freeze crystallization with CO2 hydrates for the separation of highly soluble salts from aqueous solutions has been shown (Güner 2015; Sabil, Azmi, and Mukhtar 2011; Vaessen, Ham, and Witkamp 2006). Also, CO2 hydrates have been studied as cold distribution agent and phase-change material, due to the fact that the melting temperatures are consistent with the temperature needed in these applications and the dissociation heat is suitable for refrigeration application as well as easily regenerable. CO2 hydrate based process can also be a good alternative to freeze-crystallization processes to concentrate water-rich streams which require relatively low temperatures (Sabil, Azmi, and Mukhtar 2011). Another usage of CO2 hydrate is to increase CO2 concentration in culturing algae, where its addition to algal culture systems can increase algal biomass effectively (Nakano et al. 2014). Biofuels from microalgae Microalgae cultivation can be carried out in submerged areas, infertile lands, and seawater (Mashayekhi et al. 2017; Singh, Nigam, and Murphy 2011). The cultivation of algal biomass, apart from providing biofuel feedstock, has a favorable environmental impact by reducing the concentra- tion of greenhouse gases because it uses large amounts of CO2 (Demirbaş 2009; El-Sheekh et al. 60 #cyclesofcirculation 1422 F. M. BAENA-MORENO ET AL. 2017). To choose a desired type of microalgae, a selection strategy should be considered based on various criteria such as growth rate, quantity of lipids that can be produced and its quality, response to external changes in the environment, temperature variations, nutrient input and light source, absorption speed, and affinity for nutrients, and particularly CO2, nitrogen, and phosphorus (Amaro, Guedes, and Malcata 2011; Singh, Nigam, and Murphy 2011; Ugwu, Aoyagi, and Uchiyama 2008). There are three different sources of CO2 for microalgae: atmospheric CO2, industries emissions of CO2 and CO2 from soluble carbonates (Wang et al. 2008). Moreover, there are two kinds of possible ways to carry out microalgae cultivation: in open raceway ponds or photo-bioreactors (flat-plate, annular or tubular) (Brentner, Eckelman, and Zimmerman 2011; Styring et al. 2011). Economically, bioreactors are more expensive than open-bond systems and recent research have tried to make this process cheaper in terms of capital cost and energy requirements (Brentner, Eckelman, and Zimmerman 2011). The main problem of microalgae cultivation is that a large land area is required. Also, process control is difficult, what makes the productivity to be limited (Cuéllar-Franca and Azapagic 2015). Microalgae cultivation does not compete to food markets that makes them especially interesting for futures researches. This research should be lead towards a reduction of the cultivated area needed and a reduction of general costs (Tan et al. 2018). Figure 5 presents a block diagram of the process needed to convert microalgae to biofuels. In this process, after converting a carbon source in a flue gas, a microalgae cultivation stage is employed to obtain a wastewater biomass that will be dry before its transformation into biofuels. Enhanced oil and coalbed methane recovery Throughout the life of an oil production field, there are three stages. Firstly, at the beginning of production, the oil flows naturally to the surface due to the pressure difference existing alongside the deposit. In the second phase, when the pressure in the reservoir falls, water is typically used to increase it while displacing the crude and continuing extracting it. Finally, in a third stage, the remaining oil can be recovered through various technologies with the injection of either steam or Figure 5. Biofuels from microalgae process. Modified from Tan et al. (2018). 61 #cyclesofcirculation ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1423 CO2 being the most common (Ghoodjani and Bolouri 2015). The use of CO2 as an oil or natural gas recovery agent in techniques such as EOR and ECBM, respectively, has been investigated for many years. Outcomes from both laboratory scale and industrial studies show that CO2 is an efficient agent displacing oil and natural gas (Panwar et al. 2017). EOR with CO2 injection is the second most improved hydrocarbon recovery technique after water injection according to the International Energy Agency (IEA 2015). Its application is preferable in oil fields with a depth greater than 800 m that have at least between 20% and 30% of the original oil, in which there have been previously applied secondary recovery methods (Godec, Kuuskraa, and Dipietro 2013). The injection of CO2 is not only valid for specific gravities of medium or light oils, but it has also been increasing its application year after year for the recovery of heavy oils. The flexibility of the CO2 injection process allows it to be used in a miscible or immiscible manner, depending on the existing conditions (pressure, temperature, and composition of the oil in the deposit) (Hertwich et al. 2008; Sweatman, Parker, and Crookshank 2009). Lately, EOR studies assessed the impact of various methods for allocating CO2 system emissions and the benefits of sequestration under a number of different scenarios (Godec, Kuuskraa, and Dipietro 2013; Jaramillo, Griffin, and McCoy 2009). Also, some studies developed some methodologies for the identification and screening of oil reservoirs that are suitable for CO2 flooding (Bachu, Shaw, and Pearson 2004; Dai et al. 2014). Moreover, Li et al. (2016) modified these applications for estimating CO2 seques- tration capacity at depletion as well as under enhanced oil recovery. Regarding ECBM process, studies focused on economic issues as well as potential storage in mixed gas while studying the best places to apply this during these recent years (Saghafi 2010; Jikich et al. 2004; Busch and Gensterblum 2011; BarBaran et al. 2014; Hamelinck et al. 2002). EOR has been practiced for long periods of time in countries such as the United States or Canada. However, ECBM is under test phase (IPCC 2005). The information collected in this section argues that CO2-EOR deserves to be a major part of a worldwide carbon management strategy. According to IEA, growth in production from CO2-EOR is now limited by the price of CO2 (IEA 2015). LCA studies for CCU techniques Subsequently, a comparison of the environmental impact of some CCU technologies studied based on LCA found in the literature, summarized in Table 8, will be made. LCA is a quantitative tool that allows collecting and evaluating the inputs and outputs of matter and energy and the potential impacts of a product, service, process or activity throughout the life of the product. Thus, in a complete LCA, all the environmental effects derived from the consumption of raw materials and energy necessary for production, emissions and waste generated during the productive activity as well as the environmental effects of its transportation, use, and consumption are attributed to the final product. The prerequisites that are generally important for a CCU technique to really reduce this environmental impact are the availability and use of clean energies as well as the use of raw materials that do not imply a negative environmental effect including CO2 capture (Cuéllar-Franca and Azapagic 2015; Kressirer et al. 2013). Conclusions and future prospect This study confirms that a range of CCU technologies are available for use in several applications. From direct utilization of CO2 as a solvent or for chemicals production, to obtain fuels or improve EOR techniques, with the potential for meaningful cuts in CO2 emissions and associated benefits in the industry globally. Among the different alternatives studied, the processes of carboxylation have stood out, that is the synthesis of carbonates and carboxylates. The production of salicylic acid, DMC, and mineral carbonation are presented as the most likely applications of CO2, at least in the short term. Along with the production of urea, the synthesis of salicylic acid and DMC has been carried out on an 62 #cyclesofcirculation 1424 F. M. BAENA-MORENO ET AL. 63 #cyclesofcirculation Table 8. LCA studies for some CCU options. FUNCTIONAL UNIT (kg of REFERENCE CCU OPTION PROCESS SCOPE CO2 CAPTURE METHOD CO2 per item indicated) EPA-7 2015 Carboxylation Production of salicylic LCA comparison of different methods of synthesis of salicylic acid from Post-combustion capture Production of 1 kg of acid resorcinol by K-S reaction. LCA includes initial and processing processes, via MEA salicylic acid waste disposal, isolation and purification of the final product. Comparing different reaction media and heating methods for continuous and discontinuous process. Honda et al. Acyclic Production of LCA comparison of different methods for the synthesis of DMC from Post-combustion capture Production of 1 kg of DMC 2014b carbonates dimethyl carbonate methanol. The environmental impact of the most widespread commercial via MEA methods (Eni and Ube) is compared with a process that involves the electrochemical reaction of methanol with CO2 in potassium methoxide. Khoo et al. 2011 Mineral Serpentine mineral LCA from a mineral carbonation plant in Singapore, comparing 4 Post-combustion capture Production of 1 MWh of carbonation carbonation scenarios. It is considered CO2 capture, mineral carbonation, the via MEA/Direct use of electricity in NGCC exploitation and the transport of the serpentine. CO2 is captured from combustion gases a natural gas combined cycle power plant (NGCC), analyzing capture LCA with MEA or direct use of combustion gases. Two possible yields of carbonation are distinguished. Nduagu, Mineral MgCO3 production LCA from a coal power plant located in Canada. This study includes coal Post-combustion capture Sequestration of 1 tonne of Bergerson, carbonation from CO2 and serpentine mining and transport, CO2 capture, transport and via MEA CO2 and mineralization. Zevenhoven (2012) Wang et al. Polymerization Synthesis of polyols LCA comparison of polyols based on CO2 with the conventional method Post-combustion capture Production of 1 kg of polyols 2016b based on CO2 for use for its synthesis, to use it for the production of polyurethane. The LCA via MEA and 0.36 kWh of lignite in polyurethane includes all the energy supply for obtaining the raw materials, as well as power plant electricity the CO2 capture of a lignite power plant. Elbashir et al. CO2 reforming CO2 reforming of CH4 LCA comparison of different synthesis gas production methods. Problem Post-combustion capture Production of 1 kg of (2018) of CH4 when comparing LCA since the ratio of synthesis gas produced by each via MEA synthesis gas method is very different. Campbell, Beer, Biofuels from Production of Comparative LCA of biodiesel production from microalgae between Direct injection/Post- Tonne kilometer and Batten microalgae biodiesel canola and ultra-low sulphur diesel. combustion capture via (2011) MEA Jaramillo, Enhanced oil IGCC and EOR LCA comparison among five IGCC plants including capture, compression, Pre-combustion capture The total amount of Michael recovery transport and use for EOR. via selexol electricity production during Griffin, and the project lifetime McCoy 2009 Viebahn et al. CO2 pure for Could be applied to LCA comparison of CCS to obtain a pure CO2 applied to PC, CCGT and Pre-combustion via 1 kWh of electricity (2007) multiple uses multiple processes IGCC power plants in Germany. rectisol and oxy-fuel combustion ENERGY SOURCES, PART A: RECOVERY, UTILIZATION, AND ENVIRONMENTAL EFFECTS 1425 industrial scale with success. Although at the moment, mineral carbonation has been the technology whose analysis of life cycle has reflected the most positive result on global warming prevention by reducing the net emission of CO2 into the atmosphere. As it is gathered in this paper, technological advances in this field are being a slow but constant process. The number of studies on CCU continues to increase, achieving satisfactory results and, in some cases, better than expected. Future work should be aimed at the economic improvement of the processes mentioned above, which could allow its implementation on an industrial scale, as well as at technological improvement in the development of processes to achieve a greater added value such as, for example, the synthesis of methanol, the use of CO2 consuming microalgae for the generation of ethanol and the use of electrochemical reactions that are showing initial results of great interest. 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Suess deals as well with the conceptual tools of new materialism that focus on the mechanics which extract both logistics and industry for capital, and their impacts on environments. 73 #cyclesofcirculation Distributed Resistance 65 DistributedQ Resistance, Streamlined SilkSolveig Suess Fig. 1 The train tracking system at the rail yard on the Chinese border in Dostyk is a remnant of the Soviet era, photography by James Hill for the New York Times, 2013. (Accessed from www.nytimes.com/ newsgraphics/2013/07/21/silk-road, 06/02/17) In 2012, Hewlett Packard had negotiated the construction of an alternate rail route between their Assessment and Forecasts, 2017). Faster than slow-ocean, cheaper than airfreight, this calculation led the rail route to travel from Chongqing through the Xinjiang Province into Kazakhstan, Russia, Belarus, and Poland, before reaching its destination in Germany, 11,179 kilometres later (Asia Perspective, 2017). Translated as Here, streamlined circulation is permitted through the displacement of sovereign borders, installing a new framework of transnational regulation, labour management, and security measures along with standardized units across various platforms. Later known to be part of the New Silk Road, distributive and docking 74 #cyclesofcirculation 66 SYNOPTIQUE | Vol. 8, no. 1 | spaces become key nodal events, where time and territory along its routes are converted for maximum value ongoing exploitation and resistance. With an optimization of commodity movements, the counter-efforts of slowing the desert have become increasingly pressing as Asian dust storms frequently ride the air currents, sometimes as far as California, blind to jurisdictions. The storm moves through a series of chemical transformations where during their long-range transport, its particles collide with bacteria, gases, and coagulate solid particles. “The dust aerosol [mixes] with pollution aerosol, such as industrial soot, toxic materials, and acidic gases” (Yele Sun et al, 2005) as it travels over China‘s heavily industrialized zones. Particulate matter is then scattered, congealed into a whole new series of constellations, embroiled with manufactured and chemical residue: “What emerges, then, is a contest between the tenacity of corporeal memory and the corrosive power, over time and space, of corporate amnesia emboldened by a neoliberal regime of deregulation.” (Nixon 2009, 449) They collect the corporate afterlives of the unevenly distributed ravages remnant of high-carbon industrial practices, bringing a sense of an environmental uncanniness when modernity is materially readdressed with the unintentional consequences of its own grand designs. In light of such movements, the formations of these studies on logistical innovations towards economic growth must be understood alongside managing weather behaviours and methods of containment. John Durham Peters describes what he calls “logistical media” to “establish the zero points where the x and y axes converge.” (Peters 2016, 37) Ned Rossiter includes various logistical media ranging from calendars and clocks, to addresses, maps, indexes, and logs, to extend inquiry on logistical media’s “[coordination] and control [of] the movement of labour, people, and things situated along and within global supply chains.” (Rossiter 2015, 139). Both Peters and Rossiter engage with media as ordering devices, providing a closer attentiveness to the protocols structuring the parameters in which movement occurs. With growing scholarly attention on the role of logistics in shaping the conditions of contemporary political, economic, and social life, this article seeks to bring in a more ecologically informed understanding of logistical media. Within the literature on logistics, a select number of authors take as their main focus the linkages between capitalism, modernity and imperialism (see, for example Chua, 2017; Cowen, 2010; Moten and Harney & Moten, 2013; Sekula, 2002 [1995]). However, these prior inquiries scarcely frame these histories as a longer project, where calculating material conditions such as weather acted as foundational to global forms of capitalism. Drawing on a range of reportage and theory, I utilize the conceptual tools of new materialism to capital have long colluded with spatial and environmental conditions. I use these theories to foreground the role of environmental agency where, as Karen Barad explains, agency “is about the possibilities for materialising potential.” (Barad 2007, 230) Barad’s idea of “intra-action” argues for a more performative and ‘entities,’ ‘relata’—[which] infects much of the way we understand the world and our relationship to it.”(Barad calculations, remnants from the Enlightenment, brought forth a certain assemblage of governmentality over geographies of distribution and production. (Tsing, 2012, 505) In this article I will place Paul Virillo’s notion of speed into productive tension with Anna Tsing’s terminologies of friction and scalability when speaking of geographies across the supply chain. I also aim to evoke Amitav Ghosh, Denise Ferreira da Silva, and Rob Nixon urgent calls to bring together postcolonial and environmental theories. Here I consider the intrinsically colonial past of logistics against the currently unsettled desert of Xinjiang, China. The method of argumentation in this article goes in order of three scales: from a general investigation into the relationships between weather-natural phenomena and logistics, the management of sand and wind 75 #cyclesofcirculation Distributed Resistance 67 across western Chinese territories, to the closer lens of Hewlett Packard’s involvement in the New Silk Road as case-study. I begin with the extended histories of intermediary infrastructures and their roles in co-constructing global-scale production networks, as a way to stress its importance towards understanding contemporary conditions along the New Silk Road project. To this end, I refer to the railroads from the organizations of forms and movements. In the late 1950s, the Vietnam War served as a testing ground for logistics and provided a key example of how differences were reproduced and felt along the chain. Finally, the digitalization and abstraction of pre-emptive network organization acted as a continuance of economic hierarchies between the Global North and South that we see in today’s supply chains, with Hewlett Packard taking origins from the U.S. military industrial complex. The global race to the bottom naturalizes deeply engrained inequalities, alienation, and violence. It is particularly urgent to relink these histories as we see an increase of logistical practices used as tools to remake and rescale territories. issues in western China, largely as a result of large scale social agricultural experiments. Environmental factors, such as sandstorms, interrupt the production of a smooth inter-Asian space as imagined by corporations and the state. Taking a closer look into the corporate beginnings of the Silk Road economic of supply chains with their most current involvement with Chinese state elites revealing how logistics is premised on a form of control, where the centralization of capital power in monopolistic companies rely on the state‘s cooperation in aspects of development. Hewlett Packard scaled up their operations to include monopolizing the entirety of their supply chain, where their moves contributed to the state‘s overall large-scale efforts to move industries towards the western, most arid parts of China. These networks form as a hybrid grown from China‘s reform-era politics, where the economy is controlled through state-led efforts. As the Chinese economy slows, technologies of zoning and logistical strategies become increasingly important. Infrastructural expansion rearranges cartographic space into nodes and events catering to strategies of controlled circulation and containment. These activities often lie paradoxical to the efforts of slowing the increasing environmental problems in the area. Distinctly intertwined with the securitizing and direct targeting of Xinjiang’s Uyghur minorities, the increasing ecological unpredictability and societal ills from broken lands forms a different reality on the ground to that of so-called “liquid modernity” (Bauman 2000). Sedimented Elsewheres Fig. 2 76 #cyclesofcirculation 68 SYNOPTIQUE | Vol. 8, no. 1 | The trade-winds were originally labelled to mean “steadily in one direction,” with the term “trade” borrowed from the German language during the 14th century. While historically the word simply meant a way th and 19th centuries that it took on the more familiar resonances—of business, a frequent practice of bartering (Online Etymology Dictionary, 2017). It was the th century. The logic was that one had to understand weather in order to be able to extract its use value: “The oceans and the atmosphere form a nonlinear dynamic system that contains ten times more solar energy than plants capture through photosynthesis” (Delanda 2014, 53). the relationship between turbulent waters and patterns within the currents of the Atlantic Ocean. He drew them while being Deputy Postmaster General of the Colonies, after hearing a complaint from the Board of Customs in Boston. Mail packets from England took two weeks longer to make the westward crossing than the Rhode Island merchant ships. Perplexed at this difference in time, he later found that the captains who were able to move faster were familiar with the Gulf Stream and were thus able to avoid it while traveling the westward crossing. The English captains, however, were not, and instead were being trapped in its currents while en-route (Carson 2014, 101). Like in Franklin‘s maps, boundaries were drawn to involve calculations of the wind, its currents and directions in which would later be technically engineered in favour of the through its ability to observe atmospheric conditions, used wind and currents as force multipliers of trade, engineering it alongside managerial strategies of the supply chain. They were able to use these conditions to allow for cheaper modes of production and extraction elsewhere, while speeding up nationalist, transnationalist, and corporate interests within their imperial centres. The “intra-action” in the trade winds, between the atmosphere, its windy circulations, the ships, its captains, and their maps, colluded in what accelerated the uneven formations of a whole series of relations across vast bodies of water. These formations can be interpreted as what Barad writes of in Agential Realism, the reciprocated and active formation of objects and agencies of observation within phenomena; here, “individuals emerge through and as part of their entangled intra-relating” (Barad 2007, ix). These dynamic relations continuously brought into being many elements of our current modern political geography (Ahmed 2017). Fig. 3 Department of Mechanical Engineering. Stanford University. (Accessed from courses.washington. edu/mengr543/handouts/Album-Fluid-Motion-Van-Dyke.pdf) The beginning of the 19th century marked a rupture in epistemology. With the rise of thermodynamics, thermodynamic systems, along with hydraulic metaphors of reservoirs and damming, as these concepts became essential in thought (Frow 2005, 120). With Newton‘s invention of calculus, being able to predict nature and its behaviours through clean calculations gave humanity an apparently objective viewpoint (Barad 2007, 233). Grounding the modern subject, many such instances of methodological and ontological thinking featured linear temporality and spatial separation. Theorist Denise Ferreira da Silva writes that separability is the 77 #cyclesofcirculation Distributed Resistance 69 perspective that all things of the world are able to be rationally understood through quantity, quality, relation, and modality, when gathered through space and time. Knowledge can be extracted through the understanding of its ability to be outlined, formalized, and made useful—allowing for truth claims to be deducted (da Silva 2017, 61). Symptomatic of a Cartesian split which privileged binaries, it produced hierarchies such as the mind over land to be exploited were the very foundations of modern state and law, with lines drawn separating human individuals and nature. This began what da Silva calls “a trajectory that would extend beyond the Silva 2017). Along with the seemingly objective practice of science, the Enlightenment project of modernity fueled notions of mastery and possession through reason and intellect (Serres 2011, 32). As da Silva articulates, “The emergence of modern science can be described as a shift from a concern with forms of nature, which prevailed in scholastic thought, to an inquiry into the causes of temperatures, the calculus of thresholds, and of the transformations of phases allowing for new heights of energy to be accessed. It was during this era when the telegraph, steam-powered vessels, administrative reforms, whole region became part of a single economy geared towards cotton production on a massive scale. This followed a distinct mode of upscaling, including immense projects on land irrigation, across long-distance networks, expanding the ambit of Russian imperial power and dynamics (Uryadova 2012, 5). Campaigns for modernization under later Soviet rule continued such large-scale plantations that in turn exhausted the region’s land and water networks, leading to devastating ecological effects (Kreutzmann 2016, 113). Western powers determined the shape of the global carbon economy through military and political presence in much of Asia and Africa, when steam technology was in its beginnings. to the rising costs of production and wages, and sought cheaper production costs elsewhere. The answer was to return to older colonial modes of production, where seeking extraction and cheap labour sources designed as a way for the US army to supply materials and arms in the Vietnam War (Charmaine Chua, Skype interview with author. May 05, 2017). Fig. 4 Sealand container trucks for shipping throughout the Republic of Vietnam under project HandClasp, National 78 #cyclesofcirculation 70 SYNOPTIQUE | Vol. 8, no. 1 | Together, these threads of inquiry demonstrate how environments have long been instrumentalized towards extracting value in ways which are historically contextualized. The managerial sciences of colonialism continued into logics that were later adopted by the Industrialized Global North, albeit construed through various ongoing geopolitical events. One event crucially being the U.S. involvement in the Vietnam War. During the burgeoning of the “military industrial complex” in the 1960s, new surges in state funding funnelled into developments relevant for military applications. Fluid mechanics emerged as a discipline extending from mechanical engineering that was dedicated to research for the designs of faster trains, jet engines, and re-entry physics for spacecraft and ballistic missiles. Eighty percent of graduates from these departments found employment in the defence industry (Wisnioski 2016, 103). It was at this time from industrial design to meteorology (Holmes 2007). It was also during this period that the military science of logistics was developed and digitized. Designs of containers, along with IBM‘s involvement in automated, streamlining decision-making processes which made the distribution of commodities extremely RAND (Wesley Attewell, Skype interview with author, August 9, 2017). computers but in business, development, the ‘conquest’ of nature, and, more generally, world-making. It is a form of design that has a long history of dividing winners and losers.” (Tsing 2012, 505) The art of logistics was in the method deployed through dividing and supplying various forms of life (Wesley Attewell, Skype interview with author, August 9, 2017). From 1965 onwards, the Vietnam War’s military backlog allowed for faster mobilization, which transported commodities into Vietnam, mitigating bottlenecks (Wesley Attewell, Skype interview with author, August 9, 2017). But as these systems ran through experience, when implemented, scalable data along with its differences are reproduced. Hierarchies amongst racialized labour became more pronounced, along with the ability to mobilise certain U.S. power relations in South-east Asia. It was also claimed that the experiments in management led to the sudden boom of Asian economies, nicknamed the Four Asian Tigers (Wesley Attewell, Skype interview by author. August 9, 2017). Along with the Cold War and all its uncertainties, the time period nurtured a desire for U.S.-led technological The increase of transnational mobility and geographical dispersal went together with resources for managing and servicing that network of movement. Calculations for the least amount nodes and allows for these designs to further perpetrate global modes of production foundational to power dynamics today. With the current global infrastructural project of the New Silk Road, the ordering of things are led by alliances between transnational corporations and the Chinese State. These alliances simultaneously produce frictions from their designs. While acknowledging that imperialism had crucially designed itself in relation to planetary currents such as wind, the contemporary state of imperialism is no doubt different. The New Silk Road traverses terrains which are amongst the most affected by climate change, with its long- distance infrastructures needing to be designed in ways to withstand increasingly erratic weather events. 79 #cyclesofcirculation Distributed Resistance 71 Uneasy States Fig. 5 Sand management methods along the Chongqing Xinjiang Europe rail-route, Solveig Suess, 2017 A grain of sand is found, amongst many others, covering patches of the Chongqing Xinjiang as solid as infrastructure. Despite algorithmic oversight, a relentless material disruption frequents the New Silk Road. Every grain carries the potential for interfering into the machinic workings of infrastructure on various temporal levels. The intense sand-carrying wind requires trains to be cleaned every three days, or it would have the power to corrode the surface of trains and fade its paint. Sand becomes an oxide after reacting with moisture on the ground, where it does not forget the industrial chemicals which meld into its chemical composition, nor the salt from its original bed (Chuanjiao and Chang 2015; Rahn 2007). Over a longer duration, it gradually wears down the tracks and train wheels (Windblown Sand Modelling and Mitigation Research Group 2016). Its material disturbances are happenings, enfolding into and (re) Sand becomes an agent which troubles the totalising ambitions of the New Silk Road. Encountering sand and its erratic movements provoke a feeling of the “environmental uncanny”—striking a chord of familiarity with something we had once known, but cannot seem to remember how we turned away from. Eerie moments of sudden confrontation with strange weather remind us of “the presence and proximity of nonhuman interlocutors” (Ghosh 2017, 32). The landscape is a sentient entity, one without subjectivity, but nonetheless an entity, not a background. Our recently announced current geological epoch, the Anthropocene, describes shifts in the earth‘s own physical processes as human activities have become the world-determining forces of change. But we should add that it is not just any human that produces or a set of relations, maybe an assemblage of industrial and post-industrial high-carbon lifestyles (Choy and In 2007, the press covered a hurricane-force sandstorm which derailed a train in the Xinjiang area. Some cars were knocked off the rails, others were left with cracked windows (The Associated Press, along its routes costing up to $US 23 billion (Shepard 2017). All along the New Silk Road economic belt, the infrastructure rushes through vast landscapes which clearly suffer from high degrees of aridity. Its 80 #cyclesofcirculation 72 SYNOPTIQUE | Vol. 8, no. 1 | landscapes are criss-crossed with various methods designed to keep dust and sand grounded, to prevent particulate matter from being mobilized by the winds, from transitioning its phase into suspension. Netted materials are pinned to the ground, both in grids and as vertical walls. Grids made out of stones create Train tracks undulate on and above ground, the heights determined by the intensities of the landscape‘s sand composition. 463 kilometers of windproof walls were built along the Gobi Desert stretch of the line, as well as the 3600 meter-high Qilianshan tunnel in Gansu Province (Shepard 2017). Delaying its future, governmental efforts have been organized to predict and slow the terrain‘s relentless movements eastwards, against the current of the Western economic tide. As each train carries around $US6 million-worth of goods when heading towards Europe, strong winds remain a major threat to the rail-line, particularly around the Xinjiang-Lanzhou-Urumqi 710 kilometre stretch. The faster the trains, the more of a threat they become (Jia, 2013). The sands are close reminders of the expanding deserts from the nation state’s peripheries, Xinjiang and Inner Mongolia. The low pressures in the atmosphere over the Taklamakan and Gobi deserts create windy conditions in the area during late winter and early spring. Loose top soils are picked up by westerly winds, pulling these sands into an increasingly intense Asian dust storm (Phys.org, 2017). Freezing all activity in its path, such storms have become an annual occurrence, compared to half a century ago when each phenomenon struck only once every seven or eight years. The deserts are expanding roughly 1,300 square miles a year, with movements both fast and slow. Each grain of sand carries the potential to be thrown across thousands of miles with the storm (Mullany, 2017). Over the past few decades, utopian social-agricultural experiments of high Maoist socialism have completely drained groundwater and many lakes across Xinjiang and Inner Mongolia. The Uyghur ethnic minorities of Xinjiang had previously used an extensive network of karez, a localized technique which had irrigated arid areas for millennia. These infrastructures were then replaced by large-scaled agricultural production used towards cotton plantations which resulted in its quickly receding water tables (Vanderklippe, 2017). Lop Nur, a lake that disappeared forty years ago, is now one of the four sources of sandstorms in China. Twenty percent of the country currently exists as desert, whereas in 1975 desert lands were of the deserts are “sites and material forms where we can trace emergent alignments of politics to the these areas speak of “blocking wind, holding sand” (fangfeng gusha), where it is through the control of have been known to be riskier due to overland possibilities of local ‘terrorist’ insurgencies and extreme weather events, especially those which traverse deserts. They cannot be easily governed due to shifting lands. With China‘s rail-network spanning across a wide range of climatic zones, sandstorms frequently Trains crossing the Eurasian steppes are armed with guards stationed aboard, with a high-speed rail monitoring system actively sensing and monitoring for possible risks of a transition into turbulence—wind speeds, anti-intrusion, vibration, and geological disasters (Szyliowicz et. al., 2016, 154). Maintaining an all- encompassing algorithmic oversight while traversing westwards towards Europe, the route has become one of the most monitored areas within China. Algorithmic oversight of the rail-line operates by feeding data through numerous types of radio systems, inventory histories, and the internet of things, which in turn translate back into risk assessments and security protocols informing management procedures. As business advisory manager Wing Chu explains, “Today, most logistics operators are capable of monitoring the cargo during the whole process and provide the consignor with clearance on arrival at the railway terminus, warehousing, and trans-shipment to the desired destination” (Chu 2016). Just-in-time, precision management, and forms of regulation seek to calibrate the supply chain precisely towards predictive models for the destination of goods. Virilio writes, “modernity is a world in motion, expressed in translations of 81 #cyclesofcirculation Distributed Resistance 73 Wind and its movements have not always been seen as a hindrance to production. Rather, one could towards capitalistic means. As outlined in the previous section, observing weather laid the groundwork for future techniques of predictive analytics. The project of optics and of observation came to shape the world in a particular formation which powered commerce, measurement, and forecasting, producing differences which matter. Taking cues from Karen Barad, carefully reading for such differences demonstrates how they are not predicated on conditions which are external to them but rather in entanglement, with effects produced as concrete in mattering and in material conditions. Without such an understanding and instrumentalization of weather, there would be no global capitalism as we know it. But increasing ecological disturbances signal an urgent need to shift our common-sense understandings and contemporary culture in ways which are resulting from the build-up of certain human practices, now acting as an agent of disruption feeding back onto those same practices. The replacement of the karez with state-led social agricultural experiments absorption of contingencies, fold into larger societal shifts and formations of communities. Turbulent Drag Fig. 6 Still taken from a Russian logistics company, AvtoGSM, employee surveillance camera, 24/03/15. (Accessed through www.youtube.com/watch?v=pt2lGOQnj_s, 03/02/17) In the wake of slowing economies, geographies of supply and demand currently spread themselves across vast spaces in mutable forms. Capable of absorbing peripheral communities at the edges of markets, logistical networks assist the drive of states and corporate conglomerates to continuously seek the extraction of capital in places otherwise untouched by its capture. As Virilio notes, layers of people and things move Speed fuels economic production Used now as a tool to stave off slowing economies by “bringing the outside in,” (youwai zhinei), a catchphrase amongst planners of the New Silk Road economic belt, reinforces the logistical and infrastructural as a new method of governance (Eyler, 2015). When recasting geographies 82 #cyclesofcirculation 74 SYNOPTIQUE | Vol. 8, no. 1 | of law and violence through the arranging of the inside and outside of state space, actions like land 102). Deregulated environmental and labour laws offer legal independence from the domestic laws of the host country through the creation of zones: “The zone typically provides premium utilities and a set of incentives—tax exemptions, foreign ownership of property, streamlined customs, cheap labour, and deregulation of labour or environmental laws—to entice business” (Easterling 2015, 10). Within the Chinese Communist state system, zoning technologies are devised as a distinctive way to re-territorialise national socialist space whilst generating a controlled development of capitalism (Ong 2004, 72). In the case of the New Silk Road, the transnational company Hewlett Packard initiated the inter- governmental negotiations for saving two weeks-worth of transportation time (Shepard, 2017). It was followed a move made by the company, as well as others including Foxconn and Volkswagen, to shift their factories towards China‘s western border (Abe, 2014). As part of the “Go West” program, state-led encouragement was offered to develop these western regions. The western regions are also the location of large amounts of energy and mineral resources, including coal and iron ores from the politically troubled Xinjiang Uygur autonomous region. With more speed and less cost of transporting Chinese-made goods to western markets, large incentives allowed transnational corporations like Hewlett Packard to leverage geo- politics in their favour (Frankopan, 2015). The Hewlett Packard-initiated rail-route later became part of the Chinese state‘s centralised framework of the New Silk Road Economic Belt initiative in 2015, ironing out any potential issues with bottlenecking (Yin-nor 2015, 112). There is a particular characteristic of scalability which remains faithful to the universalist notion sways and naturalizes the idea of expansion. Scalability appears across various forms throughout the supply-chain, where to be “scalable” is to be expandable without needing to rethink basic elements (Tsing 2012, 505). A common tactic of neoliberal global capitalism, or large transnational corporations, scalability describes what Rob Nixon calls “geographies of concealment in a neoliberal age” (Nixon 2009, 444). By its design, difference is disguised in homogeneity, occluding troubled relations within transnational spaces industrial complex to embed their standards within America‘s domestic policies (Weiss and Schoenberger 2015, 69). In post-war Japan, Toyota pioneered supply-chain management by moving production outside production technique, just-in-time (J.I.T) management aimed to shave off expenses and optimize, where possible, through various methods of tweaking. This technique standardized a rhythm of labour throughout the production line, with working hours described by Stefano Harney as a “killing rhythm of labour” (Wesley Attewell, Skype interview with author, August 9, 2017). It globalizes an acceptance of working the body at a rate which physically and mentally destroys it over time (Wesley Attewell, Skype interview with author, August 9, 2017). As an Economist The Economist, 2009). which then inform overall operational decisions. J.I.T management pioneered a rationalization which seeks calibration of work throughout the whole body of the supply chain (Cowen 2014, 196). economic agreements along the New Silk Road railway. Thousands of laptop computers and accessories are piled neatly in these sealed shipping containers to travel across the New Silk Road three times a week. a two-day wait for a ten percent physical container inspection has been eliminated because of the Eurasian Customs Union Agreement, allowing for goods to instead travel freely through Russia, Kazakhstan, and Belarus. Time is shaved through a shortened transit duration; inventory lists are reduced, leaving less room 83 #cyclesofcirculation Distributed Resistance 75 for complications. Objects placed in inventories are effectively tracked, allowing for quick calculations to and environmental conditions where theft or violence are also part of the production process are siphoned off as excess. Neoliberalism is an agent of general equivalence. Hewlett Packard negotiated with the Chinese government to implement their own border customs software for processing documents, permitting its containers to instead stay locked and un-inspected at border crossings en route. This allows for the inclusion of cargo inspection, quarantine, and customs capital means the arrest of movement for others. In 2016, the Uighur ethnic minorities of Xinjiang were told to hand in their passports to local authorities for “examination and management”; the area had been heavily policed for forms of separatist activity. Police checkpoints dot the area, targeting local inhabitants during the duration of the developmental works (Al Jazeera 2016). Since the development of the New Silk Road economic belt, the faster trade through these overland lines means more restrictions and containment kilometres, providing only the surface of the extremities of the police occupation and colonization in the province as big as France and Germany combined. Deborah Cowen writes that the neoliberal management and standardization, eliminating resistances including possibilities for political claims or ruptures. The management and security of the life of the whole supply chain is crucial, not just the population it serves This includes anything from identity and mobile phone screenings, WiFi sniffers, cars with compulsory tracking devices, to one meter of resolution available through satellite imagery. Xinjiang is currently the The fantasy of logistics, and where it accumulates its power, appears as the all-encompassing smooth operator, adept at hiding the fact that it needs friction in order to stay in business. Friction, in Anna Tsing’s view, is the awkward, unequal, and unstable force which “refuses the lie that the global operates as a well-oiled machine” (Tsing 2015, 6). Understanding these global points of friction is exactly what logistical solutions towards keeping costs low. Speed, then, is engineered across frictions traversing between the body and continents. Hewlett Packard’s innovations for the New Silk Road aligned with the national interests of the Chinese state in that these joint plans assisted the westward movement of industries. This is an increasingly serious collaboration, as the mitigation of risks involves both the violent arresting of the Uyghur population along with the increased deterioration of the lands. The implications of these logistical calculations are disturbing ecologies as well as societies. It is with this urgency that these processes need to be seen together as two sides of the same coin. 84 #cyclesofcirculation 76 SYNOPTIQUE | Vol. 8, no. 1 | Fig. 7 NASA’s Aqua satellite took a photo of a dust storm blowing over the Taklimakan Desert in China, 01/02/14. (Accessed from https://earthobservatory.nasa.gov/NaturalHazards/view.php?id=51705, 02/07/17) This paper has mapped logistical media through its intra-actions with weather across various scales. Backgrounding with the epistemological shifts that came with different forms of forecasting and of production, distribution, consumption, and dispossession. Long-distance networks of transportation, initially wind-dependent, later connected scalable operations of production through networks of steamships and railways, expanding the ambit of what is possible for global logistical capitalism. With the development of the military industrial complex during the Cold War underwriting a lot of how current transnational between human individuals and nature across its spatial and temporal orderings. Together, they demand we interrogate fundamental logics to how we make sense of increasingly strange weather—knowing that these storms do not merely trouble global scale ambitions, but that they are as much part of it. their agencies. The various temporal disturbances in which sand affects the railway and its supporting and goods. As sandstorms assert themselves as an undeniable threat to the infrastructure of the New Silk Road, it folds and reorganizes corporate and material histories and futures, generating their own sets of towards protecting the corpus of the supply chain. The turbulent nature of sands and winds are able to Referring to Hewlett Packard’s history of supply chain logistics, their current collaboration with Chinese state elites is crucial in understanding newer forms of logistics today. Hewlett Packard based its innovations on points of friction for keeping its industry dominance. As the New Silk Road is currently one of the most ambitious ongoing infrastructural projects in the world, it is important to observe such points 85 #cyclesofcirculation Distributed Resistance 77 of friction as they feed back and reinforce the supply chain as a whole. The corporation’s involvement with infrastructural and material conditions includes repercussions which are both environmentally and socially devastating. The calculations for speed and the least amount of resistance exceeds into biopolitical control like Hewlett Packard through the lens of logistical media enables increased attentiveness to the logics of organization that bear such spatial and temporal implications. With the engineering of immediate time and space, the long-term, delayed effects of industry and capital form what Rob Nixon would call a temporal through an amalgamation of global-scale industrial, modern, and capitalist practices. The increasing nervous attentiveness to weather prediction within these regions coincide with the province as a testbed for algorithmic governance. While western colonial projects functioned differently to Chinese state-led experiments, both fundamentally imply a dismissal of other forms of logistical organization. This can be seen through the denial of older methods of irrigation, such as the Uygher karez technique, in parallel with systemic destruction and colonial dispossession by the Chinese state. The sheer scale of control which Chinese state-elites have over various territorial decisions places is further evidence of the current urgency to examine these trans-corporate and state infrastructural collaborations. Decisions made by these collaborations shape broader hegemonic parameters coordinating a wide range of material settings, such as ports, warehouses, transport, and even university and military operations. 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Center for Strategic Assessment and Forecasts. http://csef.ru/en/oborona-i-bezopasnost/326/bitva-za-shyolkovyj-put-kazahstan- 88 #cyclesofcirculation MacKenzie, D. (2009). Making things the same: Gases, emission rights and the politics of carbon markets. Accounting, organizations and society, 34(3-4), 440-455.  A paper on the ways that markets level things out and create means of exchange for incommensurate elements, materials and value. MacKenzie’s work analyses carbon markets specifically, how these markets were created, and how something as ephemeral as atmospheric gases have come to be measured and analyzed through the “politics of market design.” 89 #cyclesofcirculation ARTICLE IN PRESS Available online at www.sciencedirect.com Accounting, Organizations and Society xxx (2008) xxx–xxx www.elsevier.com/locate/aos Making things the same: Gases, emission rights and the politics of carbon markets Donald MacKenzie School of Social and Political Studies, University of Edinburgh, Adam Ferguson Building, Edinburgh EH8 9LL, Scotland, United Kingdom Abstract This paper analyses the development of carbon markets: markets in permits to emit greenhouse gases or in credits earned by not emitting them. It describes briefly how such markets have come into being, and discusses in more detail two aspects of the efforts to ‘make things the same’ in carbon markets: how different gases are made commensurable, and how accountants have struggled to find a standard treatment of ‘emission rights’. The paper concludes by discussing the attitude that should be taken to carbon markets (for example by environmentalists) and the possibility of developing a ‘politics of market design’ oriented to making such markets more effective tools of abatement. ! 2008 Elsevier Ltd. All rights reserved. Introduction one place is made commensurate with emissions of a different gas in a different place, and how accoun- Around the world, markets in permits to emit tants have sought (so far with only limited success) greenhouse gases or in credits earned by not emit- to make ‘emission rights’ equivalent. Finally, the ting them are emerging. Some already exist; others article discusses the issue of politics: the question are in construction.1 This article describes briefly of the attitude that should to be taken to carbon the route – at the level of ‘policy’ – that has led to markets (for example by environmentalists, espe- their emergence. It then delves a little deeper into cially those who conceive of themselves as oppo- the conditions of possibility of these markets, by nents of ‘capitalism’), and the tightly-related issue examining two examples of what it takes to make of the process of market design viewed, as it has the entities traded in these markets ‘the same’. The to be, as politics. examples are how the destruction of one gas in Although the article draws upon the ‘finitist’ per- spective sketched briefly below (see Barnes, Bloor, & Henry, 1996; Hatherly, Leung, & MacKenzie, E-mail address: D.MacKenzie@ed.ac.uk 1 This paper was originally presented to the workshop ‘Carbon submitted for publication), its approach is Markets in Social-Science Perspective’, Durham University, 7 prompted by the view of economic life suggested November 2007. The research was supported by a UK Economic by the ‘actor-network’ theory of Michel Callon and Social Research Council Professorial Fellowship, RES-051- and Bruno Latour (for which see, for example, 27-0062, and I am deeply grateful to the Institute of Advanced Latour, 2005). In Callon’s and Latour’s view, the Study, Durham University for supporting the workshop and for a Fellowship which enabled me to complete the paper. characteristics of an ‘actor’ – a term which, follow- 1570-8705/$ - see front matter ! 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.aos.2008.02.004 Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 90 #cyclesofcirculation ARTICLE IN PRESS 2 D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx ing semiotics (especially Greimas, 1987), they view the risk of severe impacts rises sharply (Schellnhu- as encompassing more than just human beings – ber, 2006). are not intrinsic, but are the result of the networks In consequence, this paper is necessarily preli- of which the actor is made up and forms part. What minary. The empirical material on which I am draw- we call ‘capitalism’, for example, is not an entity ing is limited. It consists primarily of a set of 24 with fixed characteristics. ‘Que faire contre le capi- interviews conducted with people involved with car- talisme?’, they write: ‘D’abord évidemment ne pas bon markets (particularly with the European Union y croire’ (Callon & Latour, 1997, p. 67). What is Emissions Trading Scheme) as market designers, as to be done against capitalism? First of all, of course carbon traders and brokers, or as members of do not believe in it. NGOs seeking to influence the evolution of carbon In Callon’s and Latour’s view, economic life is markets. This interview material is supplemented ‘performed’ – framed and formatted – by ‘econom- by analysis of relevant documents such as monitor- ics at large’, a term that encompasses not just the ing reports and contributions to the debate in academic discipline but also economic practices accountancy touched on below. such as accounting and marketing (Callon, 1998, The article’s main aim is simply to help broaden 2007). The characteristics of economic actors and social-science research on carbon markets, both in of markets arise from, amongst other things, the terms of its disciplinary base (though their origins ‘dispositifs de calcul’ (Callon & Muniesa, 2003) – lie in economics, carbon markets cannot be under- the calculative mechanisms – of which they are stood by the conventional tools of that discipline made up. alone) and in terms of its empirical focus. In that If the characteristics of ‘capitalism’ are not inher- latter respect, I hope to show that it is productive ent, they can be changed by changing the calculative to investigate not just overall questions such as the mechanisms that constitute it. The markets in green- reasons why policy-makers might choose carbon house-gas emissions that are being constructed markets rather than other tools to combat global globally are a set of experiments (Muniesa & Cal- warming, but also the specifics of how carbon mar- lon, 2007) in the validity of this prediction. Hith- kets are constructed. Whether or not carbon mar- erto, greenhouse-gas emissions have been, in kets are environmentally and economically economists’ familiar terminology, an ‘externality’: effective depends on such specifics, and the issues from the viewpoint of the emitter, they bore no cost, involved are various and demand inter-disciplinary and so did not figure in emitters’ economic calcula- treatment. One of the two topics examined below tions. The goal of a carbon market is to bring emis- – how different gases are made commensurable – sions within the frame of economic calculation by is a natural question for the social studies of science giving them a price. In such a market, emissions and technology; the other – how to find a standard bear a cost: either a direct cost (because allowances treatment of ‘emissions rights’ – is a question obvi- to emit greenhouses gases need to be purchased), or ously suitable for researchers in accounting. an opportunity cost (because allowances that are Although for reasons of space I do not discuss them not used to cover emissions can be sold, or because here, questions for other disciplines can also easily credits can be earned if emissions are reduced below be identified: for example, vastly more needs known ‘business as usual’). A carbon market is thus an about how emission reduction projects in develop- attempt to change the construction of capitalism’s ing countries actually work in practice, a question central economic metric: profit and loss, the ‘bottom that raises issues ranging from how verification is line’. conducted to the impact of projects on local com- The experiments in carbon-market construction munities and local environments. Investigating such have scarcely begun, so the validity of the prediction issues in genuine depth requires the skills of, that capitalism can be ‘civilized’ (Latour, forthcom- amongst others, anthropologists and other area ing) by changing calculative mechanisms remains specialists. undecided. We do not yet know whether the bottom Because the specifics of market design matter, I line will be changed to any substantial extent, in make no apology for the fact that this article particular to an extent sufficient to keep global touches upon matters of apparent detail. The com- warming below the threshold (uncertain and fiercely mensurability of gases and the accounting treatment contested, but often taken to be 2 !C) beyond which of emission rights are inevitably ‘technical’ ques- tions, and those technicalities cannot altogether be Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 91 #cyclesofcirculation ARTICLE IN PRESS D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx 3 avoided: they matter to overall outcomes. The com- atively minor and sometimes ham-fisted ways in the mensurability of gases, for example, is crucial to 1970s and 1980s, mainly in the United States (see, how the world’s two main existing carbon markets e.g., Hahn, 1989). It was only in the 1990s that the – the European Union Emissions Trading Scheme idea became mainstream. and the Kyoto Protocol Clean Development Mech- The crucial development was the start of sulphur- anism – interrelate, while there is at least tentative dioxide trading in the US in 1995 (for which see, evidence that the accounting treatment of emissions especially, Ellerman, Schmalensee, Bailey, Joskow, rights affects firms’ behaviour in carbon markets. It & Montero, 2000; Burtraw, Evans, Krupnick, Pal- is precisely issues of this detailed kind that an effec- mer, & Toth, 2005). It had been known for twenty tive, inter-disciplinary analysis of carbon markets years or more that damage to the environment and will need to address. to human health was being caused by sulphur-diox- ide emissions, notably from coal-fired power sta- tions, which react in the atmosphere to produce Carbon markets ‘acid rain’ and other acid depositions. Numerous bills were presented to Congress in the 1980s to Carbon markets come in two main species: ‘cap address the problem, but all failed in the face of and trade’ and ‘project-based’.2 Let me begin with opposition from the Reagan administration and the former. It involves a government or other from Democrats who represented states that might authority setting a ‘cap’ – a maximum allowable suffer economically from controls on sulphur-diox- aggregate total quantity of emissions – and selling ide, such as the areas of Appalachia and the mid west or giving the corresponding number of allowances in which coal deposits are high in sulphur. to emitters. The authority then monitors emissions Sulphur trading broke the impasse. It combined a and fines anyone who emits without the requisite simple, clear goal that environmentalists could allowances. If the monitoring and penalties are embrace (reducing annual sulphur-dioxide emissions stringent enough, aggregate emissions are thus kept from power stations in the US by 10 million tonnes down to the level of the cap. The ‘trade’ aspect of from their 1980 level, a cut of around a half) with cap and trade arises because those for whom reduc- a market mechanism attractive to at least some tions are expensive will want to buy allowances Republicans. The cut was achieved in practice far rather than incurring disproportionate costs. The more cheaply than almost anyone had imagined. requisite supply of allowances is created by the Industry lobbyists had claimed it would cost $10 bil- financial incentive thereby provided to those who lion a year, while the actual cost was around $1 bil- can make big cuts in emissions relatively cheaply. lion. Allowance prices of $400 a tonne were They can save money by not having to buy allow- predicted, but in fact prices averaged around $150 ances, or (if allowances are distributed free) can or less in the early years of the scheme. The flexibility earn money by selling allowances they do not need. that trading gave to utilities helped to reduce costs So, as already noted, emissions, which previously (by around a half compared to having to meet a stan- had no monetary cost, now have one. dard that imposed a uniform maximum emission The origins of the idea of controlling emissions rate: see Burtraw et al., 2005; Ellerman et al., 2000) via a cap and trade scheme can be traced to the but other factors were equally important. ‘Scrub- work of Nobel Laureate Ronald Coase (1960), but bers’ to remove sulphur from smokestacks turned a more proximate source is the University of Tor- out to be cheaper to install and to run than had been onto economist Dales (1968a, 1968b), who first anticipated, and rail-freight deregulation sharply put forward the idea in something like full-fledged reduced the cost of transportation from Wyoming’s form.3 Emissions markets were implemented in rel- Powder River Basin, the main source of low-sulphur coal in the United States (Ellerman et al., 2000). 2 This article concentrates on regulatory markets, largely That the sulphur-dioxide market was, broadly, a setting aside the ‘voluntary’ market, in which, for example, firms success shaped how the Clinton Administration choose to ‘offset’ their emissions, even though they are under no approached the negotiations that led to the 1997 compulsion to do so: see, for example, Bumpus and Liverman Kyoto Protocol. In the Protocol, the industrialized (forthcoming). 3 The history of emissions trading will be treated in more detail nations undertook that by Kyoto’s 2008–2012 ‘com- in MacKenzie (submitted for publication). The brief account mitment period’ they would have limited their given here draws upon that in MacKenzie (2007). greenhouse-gas emissions to agreed proportions of Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 92 #cyclesofcirculation ARTICLE IN PRESS 4 D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx their 1990 levels: 93% for the US, 92% for the Euro- for example, China or India can thus be transformed pean Community overall (with varying levels for its into a permit to emit in Europe. member states), and so on. As with the CDM, the ETS, launched in January At the insistence of the US, Kyoto gave its signa- 2005, was shaped by political exigencies.4 What tories sulphur-like flexibility in how to meet their pushed Europe towards trading rather than its initial commitments. The Protocol contains provision for preference, harmonized carbon taxes, was in good a cap and trade market between nation-states. part an idiosyncratic feature of the political proce- States with caps they will exceed can pay others that dures of the European Union. Tax measures require in the commitment period are emitting less than unanimity: a single dissenting country can block their caps for their unneeded ‘Kyoto units’ (quanti- them. Emissions trading, in contrast, counts as an ties of carbon dioxide or their equivalents in other environmental, not a tax matter. That takes it into gases: see below). Just how much trading of such the terrain of ‘qualified majority voting’. No single units between nation-states there will be remains country can stop such a scheme: doing so takes a to be seen: it is possible it will be quite limited. More coalition of countries sufficiently populous (since significant so far have been two other Kyoto mech- voting weights roughly follow population) to form anisms – ‘Joint Implementation’ and, especially, the a ‘blocking minority’. A plan for a Europe-wide car- ‘Clean Development Mechanism’ (CDM) – which bon tax had foundered in the early 1990s in the face are project-based schemes, not cap and trade. of vehement opposition from industry and from par- Let me concentrate on the CDM (for which see, ticular member states (notably the UK), and its for example, Lecocq & Ambrosi, 2007), which is advocates knew that if they tried to revive it the una- the more important of the two. It is a crucial – per- nimity rule meant they were unlikely to succeed. ‘We haps the crucial – aspect of the Kyoto Protocol learned our lesson’, one of them told me in interview. (Grubb, 1999), crystallizing the political compro- Hence the shift in allegiance to trading. mise at the Protocol’s heart, between the refusal of In terms of volume of transactions, the ETS is the developing countries to take on emissions caps largest greenhouse-gas market. The scheme has had and the Clinton Administration’s conviction that its difficulties – the over-allocation, violent price global emissions could be restrained far more fluctuations and ‘windfall profits’ discussed below cheaply if the developing world were part of the – but it saw trades worth $24 billion in 2006 (World Kyoto regime. The CDM allows the creation of Bank, 2007, p. 3). The prospect of ‘monetizing’ Kyoto units from projects in developing countries CERs via the ETS is the main driver of investment approved by the Executive Board of the CDM (a in Clean Development Mechanism projects, which body established under the United Nations Frame- generated CERs worth $5 billion in 2006 (World work Convention on Climate Change). Bank, 2007, p. 3). Between them, the ETS and To gain approval, it must be shown that a project CDM form the core of the world’s carbon markets, is ‘additional’ (that it would not take place without and it is on them that this paper focuses. CDM funding) and that it will reduce emissions below the ‘baseline’ level they would have been at Making things the same: Gases without the project. A developing world entity, or industrialized-world government, corporation, bank The political decision to create a carbon market or hedge fund can then earn the difference between such as the CDM or ETS is not the same as con- emissions with and without the project in the form structing such a market. A new commodity – an of a specific type of Kyoto units: ‘Certified Emission emission allowance or emission credit – needs Reductions’ (CERs). A CER is a credit, not a permit brought into being: defined legally and technically, or allowance: it does not directly convey any right to allocated to market participants, made transferable emit. However, some governments are purchasing and tradable, and so on. To give a flavour of what is CERs as a way of meeting their Kyoto caps, and cru- involved, let me concentrate on one issue: the heter- cially CERs also have monetary value because the ogeneity of the means by which the ‘sameness’ – the European Union permits its member states to issue fungibility of allowances and credits – necessary for allowances in the most important cap and trade mar- ket, the European Union Emissions Trading Scheme 4 On the emergence of the ETS, see, e.g., Zapfel and Vainio (ETS), in exchange for the surrender of CERs (Euro- (2002), Christiansen and Wettestad (2003), Damro and Méndez pean Parliament, Council, 2004). A credit earned in, (2003), Wettestad (2005) and Cass (2005). Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 93 #cyclesofcirculation ARTICLE IN PRESS D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx 5 Fig. 1. The interface of the gas corrector meter in the input pipe to Edinburgh University’s central area combined heat and power plant. Photograph courtesy David Somervell, Estates and Buildings, University of Edinburgh. a carbon market is brought into being.5 Consider, sions from the combined heat and power plant are for example, two very different sites: the central-area measured using a gas corrector meter (the interface combined heat and power plant of Edinburgh Uni- of which is shown in Fig. 1) on the large pipe that versity, situated a couple of hundred meters from takes gas from the national gas grid into the plant. my office there, and the refrigerant plant operated It is called a ‘corrector meter’ because it samples by Zhejiang Juhua Co., 6.5 km south of Quzhou temperature and pressure, and can thus convert vol- City in China’s Zhejiang province. How is the activ- umes into masses of gas input, which are in turn ity at one made commensurable with that at the converted to estimates of CO2 output using stan- other, so that both can form part of the same mar- dard multiplication factors. ket, and CERs at Zhejiang Juhua’s plant can be Zhejiang Juhua Co. is involved in something equivalent to the ETS allowances that a European quite different, the manufacture of HCFC-22 (chlo- emitter such as Edinburgh University needs? rodiflouromethane), which is used mainly as a As its name indicates, the combined heat and refrigerant (especially in air conditioners), though power plant in Edinburgh generates electricity (by also as a foam blower and as a chemical feedstock. burning natural gas in a device that resembles a The standard process used to produce chlorodiflou- giant car engine), and uses what would otherwise romethane involves combining hydrogen fluoride be waste heat to warm up nearby buildings. Because and chloroform, using antimony pentachloride as its thermal input capacity is slightly greater than the a catalyst, and even when optimized the process 20 MW threshold of the European Union Emissions leads to a degree of ‘overfluoridation’: trifluorome- Trading Scheme, this plant became part of the ETS thane, HFC-23, is produced as well.6 HFC-23 is, in January 2008. (Most such installations have been unfortunately, long-lived in the atmosphere and an part of the scheme since its launch in 2005, but efficient absorber of infrared radiation; the combi- Edinburgh University was exempted from the first nation makes it a very potent greenhouse gas. phase because of its involvement in an earlier, vol- untary UK emissions trading scheme.) CO2 emis- 6 ‘HFC-23’ and ‘HCFC-22’ are not standard chemical formu- lae, but instances of a code, widely used in the refrigerant business, for identifying haloalkanes. The standard formula for 5 On commensuration in the SO2 market, see Levin and trifluoromethane is CHF3, but ‘HFC-23’ is how it is referred to in Espeland (2002). carbon markets. Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 94 #cyclesofcirculation ARTICLE IN PRESS 6 D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx Until recently, the HFC-23 was discharged into the Crucially, the allowable mass of HFC-23 that the atmosphere. Now, the Zhejiang Juhua plant’s waste measurement devices reveal has been decomposed is gases are fed into a specialised incineration furnace then multiplied by 11,700.8 By decomposing a tonne imported from Japan, in which they are mixed with of HFC-23 in China, one can – via the link between hydrogen, compressed air and steam, burned at the CDM and ETS – earn allowances to emit 11,700 1200 !C using a high-intensity vortex burner, and thus tonnes of CO2 in Europe. Certified Emission Reduc- converted to hydrogen fluoride, carbon dioxide and tions are now a major income stream for China’s hydrogen chloride. These products pass through a refrigerant plants, and for the Chinese government quencher (in which they are cooled rapidly to mini- (which imposes a 65% tax on them, hypothecated mize the formation of dioxins), and the resultant acid for environmental purposes). Indeed, HFC-23 solution is either sold or disposed of via a facility for decomposition is the biggest single sector of the treating fluoric waste (CDM Executive Board, 2007). Clean Development Mechanism, accounting for As already noted, to gain approval it must be 67% of the CERs generated in 2005 and 34% of those shown that a Clean Development Mechanism project generated in 2006 (World Bank, 2007, p. 27). Since reduces emissions below the ‘baseline’ level they would the price of CERs is likely to be a chief determinant have had in the absence of the project, which in many of the European carbon price – and thus, for exam- cases is a tricky exercise in establishing a credible coun- ple, a major input into electricity prices – the effects terfactual (Lohmann, 2005): for an introduction to the of the commensuration are considerable. issues involved, see Michaelowa (2005). In the case of The crucial figure, 11,700, is the product of a cal- HFC-23 decomposition, however, a straightforward culation of the ‘global warming potential’ (GWP) of argument has sufficed: without the decomposition pro- HFC-23 published by the Intergovernmental Panel cess, the HFC-23 would, as already noted, simply have on Climate Change. Set up in 1988 by the World been discharged into the atmosphere (CDM Executive Meteorological Organization and United Nations Board, 2007). The amount actually decomposed then Environmental Programme, the IPCC has as its needs measured, but in such a way that a connection remit the establishment of authoritative scientific is kept to the baseline of the HFC-23 that would have knowledge about climate change (see Agrawala, been emitted in the absence of the decomposition 1998a, 1998b). As the IPCC put it in 1990, GWP incinerator. (The quantity of HFC-23 generated is is ‘[a]n index... which allows the climate effects of affected by the precise parameters of the HCFC-22 the emissions of greenhouse gases to be compared. production process, and hence there is a need to reduce The GWP depends on the position and strength of the incentive to operate the process in an unoptimized the absorption bands of the gas, its lifetime in the way and generate unnecessary HFC-23 in order to atmosphere, its molecular weight and the time per- earn credits by destroying it.) So to standard equip- iod over which the climate effects are of concern’ ment such as flow meters and a gas chromatograph (Houghton, Jenkins, & Ephraums, 1990, p. 45). is added a regulation: for each tonne of HCFC-22 pro- Although very similar notions are to be found in duced, there is a maximum mass of HFC-23 whose the scientific literature of the time (see, e.g., Lashof decomposition can earn credits.7 & Ahuja, 1990), it was the IPCC itself that gave ‘global warming potential’ its canonical definition 7 RThe mass of HCFC-22 produced (which is determined by TP ax½xðtÞ%dt weighing shipping containers and storage tanks) determines the GWP ¼ ROTP ‘eligible quantity’ of HFC-23: the quantity for the incineration of O ar½rðtÞ%dt which credits can be earned. For each tonne of HCFC-22 produced by the standard antimony pentachloride process, the x designates the gas in question (e.g., HFC-23). ax is eligible quantity of HFC-23 is 0.0137 tonnes, corresponding to an estimate of the effect on the radiation balance at the lowest recorded emission level from a process optimized to minimize HFC-23 production (see McCulloch, 2005, p. 11). The the tropopause (the boundary of the upper and lower mass of gas fed into the incinerator is determined from the atmosphere) of an increase in the amount of gas in readings of a flow meter, and the concentration of HFC-23 in it is the atmosphere, an effect measured in watts per determined by gas chromatography of periodic samples. (A square meter per kilogram. x(t) is the mass of the correction for leakage is also applied.) The product of mass of gas (in tonnes) and HFC-23 concentration, up to the maximum given by the eligible quantity, is, as noted in the text, then multiplied by 8 I am grateful to Thomas Grammig and to members of the 11,700 to give the quantity of Certified Emission Reductions audience of a talk I gave at the University of Oxford for sparking earned (SGS United Kingdom Ltd., 2007). my interest in how gas equivalents are brought into being. Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 95 #cyclesofcirculation ARTICLE IN PRESS D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx 7 gas that will remain in the atmosphere at time t from IPCC’s mid-1990s estimates should be used until l kg released at time zero. TP is the overall time per- the end of the 2008–2012 commitment period.10 iod in question: in the calculation in the HFC-23 The ‘exchange rate’ of 11,700 used to translate commensuration, it is 100 years. The denominator HFC-23 into CO2 is thus an example of ‘black-box- is the equivalent integral for the reference gas, CO2. ing’ in the sense of Callon and Latour (1981) and The expressions in this equation inscribe complex MacKenzie (1990, p. 26). GWPs could be contested processes. r(t), for example, is not (and obviously in at least two senses. First, whether GWPs really could not be) determined by releasing a kilogram give the best estimates of the climatic effects of dif- of carbon dioxide and measuring what happens over ferent gases could be and has been challenged (see a century: it is a mathematical function generated Shackley & Wynne, 1997, and also Shine, Fug- from a standard model (the Bern model: see, e.g., lestvedt, Hailemariam, & Stuber, 2005, and the liter- Siegenthaler & Joos, 1992) of the exchange of car- ature cited in the latter): for example, the choice of a bon between the atmosphere, the oceans and the ter- 100-year time period is in a sense arbitrary, and very restrial biosphere. ax and ar, likewise, are in part the different GWPs can be generated if, for example, 25, products of sophisticated spectroscopic studies, 50 or 500 years is used.11 Second, GWP estimates recorded largely in a database managed by the Har- were acknowledged to be subject to significant vard–Smithsonian Center for Astrophysics. (The uncertainties, of the order of ±35% (Houghton database was originally a military project, designed et al., 1996, p. 73, 119). By 2007, for example, the to enhance understanding of absorption of infrared consensus estimate of the global warming potential radiation with a view to improving the detection of of HFC-23 had increased from 11,700 to 14,800 heat sources: see Taubes, 2004.) But ax and ar also (Intergovernmental Panel on Climate Change, assume a scenario that is believed to be helpful in 2007, p. 212). Neither of these two forms of chal- predicting the climatic impact of a gas. In this sce- lenge, however, has spilled over into the carbon nario, temperatures in the stratosphere, which are market. GWPs, with their apparent simplicity and understood as adjusting relatively quickly to such the black-box ‘possibility of use by policy-makers perturbations, have done so, while temperatures in with little further input from scientists’ (Shine the lower atmosphere and at the earth’s surface et al., 2005, p. 297) remain the way in which different (which adjust only slowly) have not.9 Again, the sce- gases are made commensurable, and the inscription nario cannot be observed empirically, so modelling of the mid-1990s’ estimates of GWPs into the Kyoto as well as spectroscopy is involved in the determina- Protocol means that uncertainties and the changing tion of ax and ar. estimates of GWPs remain inside the black-box: a In 1990, the IPCC felt able to offer estimates of the matter for technical specialists, not carbon traders. GWPs of only 19 gases, not including HFC-23, and it This black-boxing is crucial to allowing carbon labelled the figures ‘preliminary only’ (Houghton markets to encompass greenhouse gases other than et al., 1990, p. 59 & Table 2.8, p. 60). By 1995–1996, CO2: liquidity in such markets would be greatly the list had expanded to 26, and included HFC-23, reduced if the relevant ‘exchange rate’ between the GWP of which was estimated as 11,700 (Hough- gases had to be negotiated ad hoc for each ton et al., 1996, table 2.9, p. 121). Both the notion of ‘global warming potential’ and the IPCC’s mid-1990s 10 See article 5, paragraph 3 of the Kyoto Protocol, the text of estimates of GWPs were then inscribed into the which is available at http://unfccc.int/resource/docs/convkp/ Kyoto Protocol, which laid down that they should kpeng.html. Accessed 24.03.06. be used to translate emissions of other greenhouse 11 Amongst other criticisms is ‘the fact that, despite its name, the gases into their equivalents in CO2 and that the global warming potential does not purport to represent the impact of gas emissions on temperature. The GWP uses the time- integrated radiative forcing and this does not give a unique indication of the effect of pulse emissions on temperature, because 9 ‘The long-term forcing is. . .more accurately represented by of large differences in the time constants of the various that acting after the stratosphere has returned to a state of global- greenhouse gases. Although a strong greenhouse gas with a short mean radiative equilibrium. Studies with simple models show that lifetime could have the same GWP as a weaker greenhouse gas the climate response, that is, the surface temperature change, is with a longer lifetime, identical (in mass terms) pulse emissions of proportional to the radiative forcing when the radiative forcing is the two gases could cause a different temperature change at a defined in this way. . . Importantly, the proportionality constant given time. Economists have also criticised the GWP concept for is found to be the same for a wide range of forcing mechanisms’ not being based on an analysis of damages caused by the (Pinnock, Hurley, Shine, Wallington, & Smyth, 1995, p. 23227). emissions’ (Shine et al., 2005, p. 282). Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 96 #cyclesofcirculation ARTICLE IN PRESS 8 D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx transaction. Note that the black-boxing rests upon burgh University needs to emit carbon dioxide a ‘social’ factor: the authority of the Intergovern- and the CERs generated by Zhejiang Juhua Co. mental Panel on Climate Change. Although that are items that Europe’s (or indeed China’s) accoun- authority has been challenged by climate change tants have not previously encountered. What kind ‘sceptics’ and ‘deniers’, public controversy has of items are they? What accounting treatment focused on the reality, extent of and evidence for should they receive? These questions are significant anthropogenic climate change, not on matters of for the operation of carbon markets, since account- ‘detail’ such as GWPs, debate over which has ing makes economic items visible, and whether and taken place only in much more limited circles. how it does so is consequential.13 The IPCC’s authority in such detailed matters is Hatherly et al. (submitted for publication) argue thus an essential part of ‘making things the same’ that a ‘finitist’ perspective is useful for the analysis in carbon markets, by keeping the ‘exchange rates’ of accounting, especially of accounting classifica- between gases inside the black-box and separate tion, and it is particularly appropriate here. In this from political and economic disputes. perspective, how to classify an item (not just an It is perfectly possible, however, that this black- accounting item, but an item of any kind) is always boxing may become harder in the future. At the implicitly a choice. Past classifications – which are time of the Kyoto Protocol, it is unlikely that any- always finite in number, hence ‘finitism’ – influence one imagined that the figure of 11,700 for the global present classifications by analogy (‘this item is like warming potential of HFC-23 would determine a previous items we classified as X, so this should be flow of funds of the order of $3.5 billion (the likely classified as an X’), but do not determine them. total value of credits from HFC-23 decomposition Of course, classification often does not feel like a up to 2012: see Wara, 2007). As negotiations begin choice. Classifiers – bookkeepers, accountants, orni- over a successor to Kyoto, however, the financial thologists, botanists, and so on – often, probably consequences of such figures can now be seen. It is normally, come across items that seem familiar possible that GWPs will remain in practice unchal- and simply ‘see’ them as an X (‘this is an X’, not lenged – it would be very hard, given the diversity ‘I am classifying this as an X’). Items that seem to of economic interests involved, to get agreement classifiers to be unfamiliar are thus of particular on a measure other than GWPs, or on anything analytical interest, because they make implicit other than the IPCC’s estimates of them (which choice explicit. Instead of relying on habit and rou- are a ‘focal point’ in game-theoretic terms), so no tine, those involved have consciously and explicitly party to the negotiations may attempt to do so – to decide what classification is appropriate, and but it is not a foregone conclusion. the debate that is often sparked can reveal the con- tingencies that affect classification. In the run-up to the launch of the European Making things the same: ‘Emission rights’ Union Emissions Trading Scheme, the International Financial Reporting Interpretations Committee Gases are thus made the same by a combination (IFRIC), a subsidiary body of the International of measurement devices, complex natural science, Accounting Standards Board, discussed how to and the capacity (at least so far) of the Intergovern- apply accounting standards to the new items, which mental Panel on Climate Change to keep the estima- it called ‘emission rights’, which were about to come tion of global warming potentials bracketed off into being. What kind of items were they? For from carbon-market politics. But practices of many example, were they indeed ‘rights’? The IFRIC con- other kinds are also needed to make ‘carbon’ fungi- cluded that they were not: ‘an allowance itself does ble, and amongst these accounting is of particular importance.12 The European allowances that Edin- 13 The issue of devising appropriate frameworks for making 12 I am deeply grateful to Allan Cook, who served as Co- carbon emissions ‘visible’, for example in corporate accounts, has ordinator for the International Financial Reporting Interpreta- received considerable attention: see, for example, the work of tions Committee at the end of the period in question for his help Fred Wellington and his colleagues at the World Resources in the research underpinning this section. Cook (forthcoming) is Institute (such as Lash & Wellington, 2007) and The Prince’s his own account of these events. For broader legal debate over Charities (2007). How to account for emissions allowances, the nature of carbon credits and allowances, see, Wemaere and however, has received much less attention: see Cook (forthcom- Streck (2005). ing) and Casamento (2005). Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 97 #cyclesofcirculation ARTICLE IN PRESS D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx 9 not confer a right to emit. Rather it is the instru- visions’ whose treatment should follow IAS 37 ment that must be delivered in order to settle the (IFRIC, 2004, p. 7). obligation that arises from emissions’ (IFRIC, The IFRIC’s conclusions – crystallised in IFRIC 2004, p. 19).14 Interpretation 3: Emission Rights, issued in Decem- An allowance was, however, in the IFRIC’s view ber 2004, on the eve of the start of the European clearly an asset. But what was its nature? Was it an Union Emissions Trading Scheme – thus made ‘intangible asset’ – ‘An identifiable non-monetary ‘emission rights’ the same by laying down a homo- asset without physical substance’ (IASB, 2005, p. geneous approach to accounting for them, in which, 2227) – and thus within the scope of International for example, an allowance received free by an indus- Accounting Standard (IAS) 38? Or was it a ‘finan- trial company or bought by an investment bank cial instrument’ – a ‘contract that gives rise to both were both treated in the same way as intangible a financial asset of one entity and a financial liability assets. However, IFRIC 3 encountered strong oppo- or equity instrument of another entity’ (IASB, 2005, sition, with critics arguing that the relationship of p. 2219) – and thus within the scope of the standard IFRIC 3 to the three relevant standards – IAS 20, governing such instruments, IAS 39? Some of those 37 and 38 – would create accounting mismatches, who commented on the IFRIC’s initial draft argued especially in the light of anticipated changes to that an allowance was indeed a financial instrument, IAS 20, which if made will mean that non-repayable but the IFRIC disagreed: though allowances ‘have government grants have to be recognized when they some features that are more commonly found in are received (see Cook, forthcoming). For example, financial assets than in intangible assets’ – such as the fair value of the allowances that a company being ‘traded in a ready market’ – they were not received free would have to be recognized immedi- financial instruments (IFRIC, 2004, p. 21). ately as income, while the costs of the corresponding An allowance was thus, in the IFRIC’s view, an emissions would be recognized only gradually as intangible asset, and therefore governed by IAS they accumulated. 38. If governments issued allowances at less than Reflecting the criticism of IFRIC 3, the Euro- their market value (most have issued them free-of- pean Financial Reporting Advisory Group told charge) the difference was, IFRIC decided, a ‘gov- the European Commission in June 2005 that the ernment grant’, and its accounting treatment should interpretation ‘will not always result in economic therefore follow the relevant standard, IAS 20. reality being reflected’, and recommended that the Emissions themselves – as noted, previously outside Commission not endorse it.15 The following month, an economic or accounting frame – now had to the International Accounting Standards Board, come within it. The emissions of those governed while defending IFRIC 3 as ‘an appropriate inter- by cap-and-trade schemes should, said the IFRIC, pretation’ of existing accounting standards, be treated as giving rise to liabilities that were ‘pro- acknowledged that it ‘creates unsatisfactory mea- surement and reporting mismatches’ and withdrew it.16 14 ‘It therefore follows that a participant in a cap and trade There was, of course, a ‘bottom line’ issue under- scheme does not consume the economic benefits of an allowance pinning the controversy surrounding IFRIC 3. Cor- as a result of its emissions. Rather a participant realises the porations generally fear earnings volatility: there is benefits of that allowance by surrendering it to settle the obligation that arises from producing emissions (or by selling it a widespread conviction that investors prefer earn- to another entity). Therefore, the IFRIC observed that amorti- ings that rise smoothly to those that fluctuate, even sation, which is the systematic allocation of the cost of an asset to around the same underlying trend. IFRIC 3 threa- reflect the consumption of the economic benefits of that asset tened to produce volatility that, in its critics’ eyes, over its useful life, is incompatible with the way the benefits of the would be artificial. For example, the advantage, allowances are realised. Although the IFRIC agreed that this for corporations, of classifying an ‘emission right’ observation pointed to precluding amortisation, it agreed with those respondents who highlighted that in some cases such a requirement could be inconsistent with the requirements of IAS [International Accounting Standard] 38. The IFRIC therefore 15 Letter from Stig Enevoldsen to Alexander Schaub, 6 May decided not to proceed with its proposal... that allowances should 2005. Available from http://www.iasplus.com/interps/ not be amortised. Nonetheless, for most allowances traded in an ifric003.htm. Accessed 11.07.07. active market, no amortisation will be required, because the 16 International Accounting Standards Board, ‘IASB withdraws residual value will be the same as cost and hence the depreciable IFRIC Interpretation on Emission Rights’, available from http:// amount will be zero.’ (IFRIC, 2004, pp. 22–23). www.iasplus.com/interps/ifric003.htm. Accessed 11.07.07. Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 98 #cyclesofcirculation ARTICLE IN PRESS 10 D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx as a financial instrument would have been that it shouldn’t change? An economist will quickly tell would make available the ‘hedge accounting’ treat- you what’s wrong with that argument. As already ment permitted under IAS 39. If allowances could noted, there’s an opportunity cost involved. In a ‘be treated as the hedging instrument of a forecast ‘perfect market’, a profit-maximizing firm will pro- transaction (ie future emissions)’ (IFRIC, 2004, p. duce electricity only if the price it receives is greater 20), then allowances and the corresponding emis- than what it can earn by not generating electricity sions would offset each other. If a company received and selling its stocks of the required inputs: its coal, N free allowances, forecast emissions of N tonnes of its gas, and now its carbon allowances (Point Car- carbon dioxide, and emitted N tonnes, then its earn- bon, 2007, pp. 24–25). If its allowances can com- ings would at no point be affected. ‘Carbon’ would mand a non-zero price, the price of electricity thus remain invisible. must rise correspondingly. The withdrawal of IFRIC 3 means that it According to an interviewee in the electricity remains permissible to treat carbon in this way: as market, however, it has required accountants to give inside an economic frame, but in a sense invisibly force to this economists’ reasoning. The ‘naı̈ve’ view so, since no accounting recognition is needed if the prevailed in the industry until explicit valuations of above conditions are met. A survey by Deloitte allowances started to be made. The price effect (2007) found that some market participants were ‘should’ have been manifest in forward contracts doing just that. Others were in effect following covering supply from January 2005 (the start of IFRIC 3, while others again were doing so partially, the ETS) onwards, but apparently it initially was treating the provision for the liability created by not.18 The effect began in the UK only once January emissions in a different way.17 The attempt to make 2005 was reached, and analysis by the consultancy ‘emission rights’ the same has, in this sense, so far Point Carbon (2007) suggests it was even slower to failed. appear on the Continent. (Once the effect began, The partial invisibility of carbon also means that the result in the UK was, for example, an increase the incorporation of the carbon price into the mar- in domestic electricity prices in 2005 of around ket’s ‘calculative mechanisms’ (Callon & Muniesa, 7%19 – for example, about £20 on a £300 annual bill 2003) is only partial. Although it is impossible to – and it is increases of this kind that are the source be certain, there is tentative evidence from my inter- of the much-criticized ‘windfall profits’ that electric- view data of effects of both the accounting visibility ity generators have made from the Emissions Trad- of carbon in some firms and its invisibility in others. ing Scheme.) Consider, for example, the effect of the European Carbon has thus been ‘visible’ for some time in Union Emissions Trading Scheme on electricity the electricity sector. When, in contrast, carbon is prices. If allowances are distributed free, one might kept invisible in accounting terms effects of three naı̈vely think that they should have no effect on the price of electricity. If a generator is given enough allowances to cover its emissions (most generators 18 This is an interviewee’s assertion. Unfortunately, I do not have actually had to buy some allowances, but let have access to the price data needed to test it quantitatively. me set that aside), what it charges customers surely 19 Calculation by Karsten Neuhoff, quoted on BBC Radio 4, ‘File on Four’, 5 June 2007. Controversy is growing across Europe about these ‘windfall profits’. In the UK, for example, the energy regulator Ofgem has called for the windfall profits of the 17 Deloitte (2007) does not estimate the relative prevalence of the UK’s electricity generators in the 2008–2012 phase of the three forms of accounting treatment. Those in the third category Emissions Trading Scheme – which Ofgem estimates at £9 billion ‘recognise a provision on the following bases: To the extent that – to be used to help customers in fuel poverty (Crooks, 2007). In the entity holds a sufficient number of allowances, the provision Germany, the Bundeskartellamt (Federal cartel office) charged should be recognized based on the carrying value of those electricity generator RWE with behaving illegally by incorporat- allowances (i.e., the cost to the entity of extinguishing their ing in the price it charged industrial consumers the market value obligation). To the extent that the entity does not hold a sufficient of permits it had received free. The case was settled out of court in number of allowances, the provision should be recognized based September 2007, with RWE continuing to defend its pricing but on the market value of emission rights required to cover the agreeing that in 2009–2012 it would hold annual auctions of shortfall; and the penalty that the entity will incur if it is unable to quantities of power almost equivalent to its annual sales to obtain allowances to meet their obligations under the scheme, German industry (46,000 GWh in total over the 4 years) and and it is anticipated that the penalty will be incurred (note that transfer to the purchasers, free of charge, the corresponding the obligation to deliver allowances must still be fulfilled).’ carbon allowances if it had received these at no cost (RWE AG, (Deloitte, 2007, p. 3) 2007). Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 99 #cyclesofcirculation ARTICLE IN PRESS D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx 11 kinds can be anticipated. The first, which is hypo- thetical (I have no direct evidence on the point), would be to undermine a major desired effect of a carbon market: incentivizing even those compa- nies which have ‘enough’ allowances to cut their emissions so as to generate income by selling allowances. For this effect to be realized, allow- ances need to be seen as assets with potential monetary value, not simply as means of complying with regulatory requirements. The second, related effect (of which there is some tentative evidence) is to delay the sale of allowances by those who, even without abatement, have more allowances than they need. The sale of allowances – and also lending allowances for short sale – means that Fig. 2. Price history of allowances, phase I of European Union they can no longer be kept invisible. They must Emissions Trading Scheme. Courtesy Point Carbon. be recognized in accounting terms, and, for exam- ple, a tax liability may be crystallized. This disin- ances accounts for this paradoxical behaviour of centive may reinforce other reasons for not the carbon price. Even though it was clear that selling, such as the fact that emission levels will allowances were intrinsically close to worthless in general be known in advance only approxi- (because, in aggregate, there were more of them mately and the lack of a culture of proprietary, than would be needed), they still commanded a risk-taking trading in many industrial companies price of several euros, because not enough were (in contrast to electricity suppliers, which are brought to market.20 active traders) that would permit the sale of allow- The third – again hypothetical – effect of the ances that probably – but not certainly – will not accounting invisibility of carbon may be to be needed. strengthen the hand of managers whose interests My interview data do not permit me to judge lie in protecting market share by not passing on to the relative importance of the various reasons for customers the opportunity cost of allowances that postponing the sale of allowances that are likely have been allocated free, even when passing on the to be surplus to requirements, but those intervie- cost is profit-maximizing for their firms. The extent wees with whom I explored the topic all believed to which firms pass on the opportunity cost is cru- delayed sale to be a real phenomenon. It has been cial to the environmental effects of a cap-and-trade consequential because the complex process of set- market – if they pass it on, there is likely to be car- ting national allocations for the first phase (Janu- bon ‘leakage’ from the scheme, as imports from out- ary 2005–December 2007) of the European scheme side its boundaries become more attractive – and led to over-allocation of allowances. The extent of there is fierce controversy over likely behaviour in over-allocation was, however, not clear initially, this respect. Economists tend to predict profit-max- and the failure of those who were ‘long’ allow- imization, cost pass-through and thus leakage, while ances to bring them to market led to a constric- firms themselves tend to argue that market share tion of supply, which helped market prices to will be protected and costs will not be passed rise to €31/tonne (see Fig. 2). Curiously, when through, at least in full. Unfortunately, empirical the extent of over-allocation became clear in the analysis of the Emissions Trading Scheme so far is spring of 2006, prices – though plunging dramati- too limited to be confident how firms outside the cally – did not initially fully reflect the fact that electricity sector have behaved in this respect: see allowances no longer had any significant economic Carbon Trust (2008). value. It took several months for the market price of a phase-one European allowance to fall close to zero (only in 2007 did prices become in effect zero, with allowances towards the end of the year cost- 20 One interviewee, at a hedge fund, reported making a ing less than €0.10/tonne). Interviewees suggested considerable amount of money by taking a short position in that delayed sale by those who were ‘long’ allow- allowances in this period. Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 100 #cyclesofcirculation ARTICLE IN PRESS 12 D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx The politics of carbon markets HCFC-22 will not expand the market for it very much. However, the de facto subsidy may slow the One could go deeper into the issue of fungibility, replacement of HCFC-22 by more environmentally of making things the same. A trade, for example, is friendly refrigerants. (HCFC-22 is an ozone deplet- a legal transaction requiring documentation, and er, the use of which as a refrigerant will eventually with three bodies (the International Swaps and be phased out under the Montreal Protocol govern- Derivatives Association, the European Federation ing such substances, and it is also a greenhouse of Energy Traders, and the International Emissions agent, though not as potent as HFC-23.) Because Trading Association) competing in this sphere, of fears of this kind, ‘new’ HCFC-22 production interviewees reported that it has taken orchestrated (i.e., over and above 2000–2004 levels) is currently action to reduce the differences to a level at which a not eligible for CDM credits, but the consequence trade documented in one format can be regarded as is that there is no economic incentive not simply to similar enough to one documented in another, for discharge HFC-23 from such new production into example for one to be used to hedge the other. the atmosphere rather than decomposing it. There has also, for instance, been sharp criticism In the light of issues such as these, it is tempting from competitors of the efforts by Barclays Capital, to conclude that carbon markets are inherently a leading player in the carbon market, to standard- flawed means of achieving abatement. As Callon ise CERs via its SCERFA (Standard CER Forward (1998) points out, constructing a market requires Agreement). The competitors regard a SCERFA as an enormous degree of ‘cooling’: of knowledge, of specific to Barclays, not as a ‘standard’ entity. metrologies, of actors, of identities, of interests. In Instead, however, let me consider the question of a perceptive article, Lohmann (2005, pp. 211 and the attitude to be taken to carbon markets. There is 229) applies Callon’s analysis to the carbon market a great deal of suspicion of them, ranging from right- and essentially concludes that market construction wing distaste for emissions caps to leftwing hostility to will indeed fail: ‘conditions are not cool enough an extension of market relations. The efforts at market for the spadework for commercial relations’, and construction so far have led to some environmental ‘an unstoppable fount of complexity’ has been benefits – for example, because of HFC-23’s potency, uncorked. curbing emissions of it is very valuable – but also sig- Indeed, much of what I have described is consis- nificant problems. There has, for example, been only tent with a bleak, essentialized view of capitalism, as modest abatement by Europe’s electricity producers inherently irresponsible and environmentally dam- (the sharp rise in gas prices in 2005–2006 swamped aging, rather than Callon and Latour’s more opti- any carbon-price incentive to switch from coal to mistic perspective. Yet the conclusion that carbon gas), while the mechanism discussed above led them, markets are inherently flawed carries a risk. Aban- as noted, to make substantial windfall profits. donment of such markets might well mean no seri- Similarly, the large sums that can be earned by ous international abatement efforts, rather than decomposing HFC-23 also create substantial profits, abatement by other means. If the Emissions Trading because the costs of decomposition are modest. A Scheme were abandoned, could the European specialized incinerator of the kind needed costs Union find a viable alternative, and how long would around $4–5 million to install and $20,000 a month it take? The political viability of a harmonized car- to run (McCulloch, 2005, p. 12). Even with China’s bon tax, the obvious other route, remains question- 65% tax, a large HCFC-22 plant can recoup the able, because of the unanimity required. installation cost in a few months and go on to earn Similarly, political constraints mean that if inter- revenues of well over a million dollars a month. national agreement on a replacement for the Kyoto There is debate over just how much the subsidy Protocol can be reached, it is likely to include some- increases HCFC-22 production: McCulloch (2005) thing similar to the Clean Development Mechanism. argues that because the cost of HCFC-22 is only a The CDM is, as noted, a result of the need to secure small proportion of the costs of the products in developing-country participation in abatement which it is used,21 a reduction in the price of efforts in a context in which the developing world was and is unwilling to take on caps: even caps post- 21 An air conditioning unit retailing at $500–1000 needs less than poned to a later date, given the risk that by then a kilogram of HCFC-22, which costs around $1–$2 (McCulloch, many of the cheaper opportunities for abatement 2005, p. 7). might be exhausted. The reluctance is understand- Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 101 #cyclesofcirculation ARTICLE IN PRESS D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx 13 able, given the desire not to allow a problem caused effects. Although from the viewpoint of the Kyoto by the industrialized countries to serve as a brake Protocol or of monetizability via the European upon development, and it is likely to persist – even Emissions Trading Scheme, an ordinary and a gold in a context in which China, in particular, no longer standard CER are identical, my interviewees fits the traditional template of a developing country. reported that the market price of the latter is now Abatement efforts in the developing world are thus around 10–20% higher. (They suggest that the cause likely to continue to require funding from the devel- of the higher price is that those who are buying oped world. Of course, such funding could be CERs not just for compliance but to achieve ‘car- achieved by direct government aid – Wara (2007) bon neutrality’ or other forms of offsetting fear rep- points out that HFC-23 decomposition could have utational risk if it is discovered that ‘neutrality’ is been achieved far more cheaply via this route than being achieved via industrial gas projects such as via the CDM – but that again raises the question HFC-23.) ‘Multiple monies’ have emerged in the of whether governments would in practice make carbon market, as a result of intervention by the requisite large transfers of resources.22 activists. To conclude that carbon markets must fail may The intervention by the World Wildlife Fund and also be unduly pessimistic, in that it would miss other NGOs was informal: it did not alter the for- the extent to which carbon markets hitherto have mal procedures of the CDM. However, NGOs are been experimental, in the case of phase 1 of the also seeking to practise a politics of market design European Union Emissions Trading Scheme, quite in a more formal sense, seeking to alter rules and explicitly so: interviewees involved in establishing procedures. That, indeed, is precisely the course of it reported the many compromises that had to be action that Callon and Latour’s perspective implies. made to get it up and running, such as the fact that If markets are plural – Callon’s best-known work is it was possible to challenge only the most egre- titled The Laws of the Markets (Callon, 1998) – and giously over-generous national allocations of allow- ‘capitalism’ has no unalterable essence, then this ances. While existing carbon markets may indeed be productive. unquestionably have major flaws, those flaws are Such efforts are too recent and too limited to increasingly becoming manifest, and ways of reme- know whether they will be successful. However, it dying them are available. Thus, windfall profits is worth noting that changes in market design of a within the European scheme could be eliminated kind that seem potentially achievable could be con- by moving from free allocation to full auctioning sequential. Take the underlying issue of a carbon (Dales’s original proposal), and there is now a real market versus a carbon tax. Many environmental possibility that this will happen from 2013 on, at activists prefer the latter, as do some economists least in the electricity sector. such as Nordhaus (2007). Nordhaus argues that If carbon markets are here to stay, can they be the classic analysis by Weitzman (1974) of the con- improved? One example of a successful intervention ditions that influence the relative efficiency of ‘quan- is of particular interest from the viewpoint of this tity-based’ instruments (such as a cap-and-trade paper, because it involves making things not the scheme) and ‘price-based’ instruments (such as a same. NGOs, especially the World Wildlife Fund, carbon tax) suggests, given the specific cost-benefit have sought to create a separate category of ‘gold features of combating global warming, the superior standard’ CERs, covering only renewable energy efficiency of a carbon tax. and energy conservation projects, and excluding Yet carbon markets seem politically feasible, industrial gas projects such as HFC-23 decomposi- even in the US; carbon taxes may not be, even in tion.23 The gold standard is a form of cooling in Europe. Intriguingly, however, a cap-and-trade Callon’s sense (as with the CDM as a whole, there market, with full auctioning rather than free alloca- is a formal methodology, automated tools, a role tion, can be equivalent to an optimally set tax. In for auditors, and so on), and there are ‘bottom-line’ both, polluters pay, either by having to buy permits or by paying the carbon tax. Indeed, under admit- tedly ‘idealized conditions’ (Hepburn, 2006, p. 22 For an intriguing suggestion of a means of achieving north– 229) they pay the same amounts, and the environ- south transfers at a sufficient level to make a significant impact on developing countries’ needs to adapt to climate change, see mental outcomes are the same. Thus, if the relation- Müller and Hepburn (2006). ship between emission levels and the carbon price is 23 See http://www.cdmgoldstandard.org. Accessed 17.01.08. known with certainty, either a cap-and-trade market Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 102 #cyclesofcirculation ARTICLE IN PRESS 14 D. MacKenzie / Accounting, Organizations and Society xxx (2008) xxx–xxx or a correctly set tax can achieve a required level of politics’ in Beck’s sense: politics ‘outside and abatement, and the necessary tax rate will be the beyond the representative institutions of the polit- same as the allowance price. Of course, the relation- ical system of nation-states’ (Beck, 1996, p. 18; see ship between emission levels and the carbon price is Holzer & Sørensen, 2003). For example, the not known with certainty, and for that and other IFRIC and now the International Accounting reasons the full equivalence between tradable per- Standards Board (which is turning its attention mits and a tax does not pertain in the real world. to emission rights) have to contend with pressure However, economists’ analyses suggest ways of that has had the effect of blocking efforts to ‘make designing a carbon market that might make it and things the same’ in carbon markets. In the case of a tax more closely equivalent in practice. These the IPCC, the key ‘subpolitical’ matter is, para- include rules facilitating the ‘banking’ of permits doxically, preserving the boundary between ‘sci- for future use and the ‘borrowing’ of permits from ence’ and ‘politics’, since that boundary is future years, regulated perhaps by an adjustable precisely what is needed to facilitate political requirement for firms to hold a certain amount of action, because it matters that action can be seen permits in reserve, analogous to the adjustable as based upon ‘sound science’. reserves that banks are required to hold (Newell, The subpolitics of carbon markets may seem Pizer, & Zhang, 2005). esoteric, and it is certainly not simple, but it is Precisely because of the similarity of auctioning important. Clearly, such markets are only one tool to a carbon tax, emissions markets seem almost for combating global warming, and other tools are always initially to involve free allocation, because also important: direct regulation, carbon taxes this reduces lobbying against them and political (where these are feasible), greatly increased public opposition. However, once markets are well-estab- expenditure on research and development and on lished, as the European Union Emissions Trading necessary infrastructure (for example, the electric- Scheme now is, shifting to auctioning may become ity grid changes needed to make increased renew- easier (especially now the ‘economic experiment’ ables production more attractive economically), of Phase I of the ETS has made publicly visible the removal of the many subsidies for fossil-fuel the problems that free allocation leads to). For extraction and use, and so on (see, for example, example, in October 2007 Sweden announced that Lohmann, 2006; Prins & Rayner, 2007). Neverthe- it was ending free allocation of allowances to its less, making carbon markets more effective is cru- electricity and heat sectors.24 Indeed, as noted cial, and the esoteric nature of their subpolitics above, it seems increasingly likely that in the third means that researchers have a particularly salient phase of the ETS, from 2013 onwards, auctioning role to play in bringing to light matters of appar- may be much more heavily employed, at least for ent detail that in fact play critical roles in this sectors such as electricity that cannot in practice respect. easily move production outside of the European It is this author’s hope that this paper will Union. encourage the work of this kind that is so badly The effort to shift the ETS to auctioning is ‘pol- needed. The existing and planned experiments in itics’ of a classic, recognizable kind, involving gov- changing capitalism’s bottom line are heteroge- ernments, the policy-makers of a supranational neous, widely diffused worldwide, and involve many body, nation-state representatives, fierce industry aspects – scientific, technological, political, account- lobbying against auctioning, and so on. Not all ing, sociological, anthropological, geographical – the politics of carbon markets, however, fits that beyond economics as narrowly conceived. The recognizable template. Neither the IPCC nor the experiments need ‘witnesses’ (Shapin & Schaffer, International Accounting Standards Board see 1985), and those witnesses must be multiple: lay as themselves as political bodies, and indeed it is of well as professional, from many countries, and if particular importance that the former not be seen they are academics from many disciplines.25 Carbon as political, despite the efforts of its critics to paint markets need to become part of a process of ‘social it as such. Yet they are arguably locales of ‘sub- learning’ (qv Williams, Stewart, & Slack, 2005), in which institutions to mitigate climate change are 24 Announcement of Environment Minister Anders Calgren, reported by news service Point Carbon (www.pointcarbon.com). 11.10.2007. 25 I owe this way of formulating the matter to Andrew Barry. 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Please cite this article in press as: MacKenzie, D. , Making things the same: Gases, emission rights and the ..., Account- ing, Organizations and Society (2008), doi:10.1016/j.aos.2008.02.004 105 #cyclesofcirculation TRACE CARBON ja@jamieallen.com csinders@gmail.com #cyclesofcirculation 106 #cyclesofcirculation