Mobility particle size spectrometers. harmonization of technical standards and data structure to facilitate high quality long-term observations of atmospheric particle number size distributions

Abstract. Mobility particle size spectrometers often referred to as DMPS (Differential Mobility Particle Sizers) or SMPS (Scanning Mobility Particle Sizers) have found a wide range of applications in atmospheric aerosol research. However, comparability of measurements conducted world-wide is hampered by lack of generally accepted technical standards and guidelines with respect to the instrumental set-up, measurement mode, data evaluation as well as quality control. Technical standards were developed for a minimum requirement of mobility size spectrometry to perform long-term atmospheric aerosol measurements. Technical recommendations include continuous monitoring of flow rates, temperature, pressure, and relative humidity for the sheath and sample air in the differential mobility analyzer. We compared commercial and custom-made inversion routines to calculate the particle number size distributions from the measured electrical mobility distribution. All inversion routines are comparable within few per cent uncertainty for a given set of raw data. Furthermore, this work summarizes the results from several instrument intercomparison workshops conducted within the European infrastructure project EUSAAR (European Supersites for Atmospheric Aerosol Research) and ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure Network) to determine present uncertainties especially of custom-built mobility particle size spectrometers. Under controlled laboratory conditions, the particle number size distributions from 20 to 200 nm determined by mobility particle size spectrometers of different design are within an uncertainty range of around ±10% after correcting internal particle losses, while below and above this size range the discrepancies increased. For particles larger than 200 nm, the uncertainty range increased to 30%, which could not be explained. The network reference mobility spectrometers with identical design agreed within ±4% in the peak particle number concentration when all settings were done carefully. The consistency of these reference instruments to the total particle number concentration was demonstrated to be less than 5%. Additionally, a new data structure for particle number size distributions was introduced to store and disseminate the data at EMEP (European Monitoring and Evaluation Program). This structure contains three levels: raw data, processed data, and final particle size distributions. Importantly, we recommend reporting raw measurements including all relevant instrument parameters as well as a complete documentation on all data transformation and correction steps. These technical and data structure standards aim to enhance the quality of long-term size distribution measurements, their comparability between different networks and sites, and their transparency and traceability back to raw data.

Schlagwörter

Fachgebiet (DDC)

550 - Geowissenschaften

Projekt

Veranstaltung

Startdatum der Ausstellung

Enddatum der Ausstellung

Startdatum der Konferenz

Enddatum der Konferenz

Datum der letzten Prüfung

ISBN

ISSN

1867-1381

Sprache

Englisch

Während FHNW Zugehörigkeit erstellt

Nein

Publikationsstatus

Veröffentlicht

Begutachtung

Peer-Review der ganzen Publikation

Open Access-Status

Gold

Lizenz

Zitation

WIEDENSOHLER, Alfred, Wolfram BIRMILI, Marta NOWAK, A. SONNTAG, Kay WEINHOLD, M. MERKEL, Birgit WEHNER, T. TUCH, S. PFEIFER, Markus FIEBIG, Ann Mari FJÄRAA, Eija ASMI, Karine SELLEGRI, R. DEPUY, H. VENZAC, P. VILLANI, Paolo LAJ, P. AALTO, J. A. OGREN, Erik SWIETLICKI, P. WILLIAMS, P. ROLDIN, P. QUINCEY, C. HÜGLIN, R. FIERZ-SCHMIDHAUSER, Martin GYSEL, Ernest WEINGARTNER, Francesco RICCOBONO, S. SANTOS, C. GRÜNING, K. FALOON, D. BEDDOWS, Roy HARRISON, C. MONAHAN, Stephen G. JENNINGS, Colin D. O’DOWD, A. MARINONI, H.-G. HORN, L. KECK, J. JIANG, J. SCHECKMAN, P. H. MCMURRY, Z. DENG, C. S. ZHAO, M. MOERMAN, B. HENZING, G. DE LEEUW, G. LÖSCHAU und S. BASTIAN, 2012. Mobility particle size spectrometers. harmonization of technical standards and data structure to facilitate high quality long-term observations of atmospheric particle number size distributions. Atmospheric Measurement Techniques. 29 März 2012. Bd. 5, Nr. 3, S. 657–685. DOI 10.5194/amt-5-657-2012. Verfügbar unter: https://doi.org/10.26041/fhnw-9110

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