Ice residual properties in mixed‐phase clouds at the high‐alpine Jungfraujoch site

Ice residual (IR) and total aerosol properties were measured in mixed‐phase clouds (MPCs) at the high‐alpine Jungfraujoch research station. Black carbon (BC) content and coating thickness of BC‐containing particles were determined using single‐particle soot photometers. The ice activated fraction (IAF), derived from a comparison of IR and total aerosol particle size distributions, showed an enrichment of large particles in the IR, with an increase in the IAF from values on the order of 10−4to 10 for 100 nm (diameter) particles to 0.2 to 0.3 for 1 μm (diameter) particles. Nonetheless, due to the high number fraction of submicrometer particles with respect to total particle number, IR size distributions were still dominated by the submicrometer aerosol. A comparison of simultaneously measured number size distributions of BC‐free and BC‐containing IR and total aerosol particles showed depletion of BC by number in the IR, suggesting that BC does not play a significant role in ice nucleation in MPCs at the Jungfraujoch. The potential anthropogenic climate impact of BC via the glaciation effect in MPCs is therefore likely to be negligible at this site and in environments with similar meteorological conditions and a similar aerosol population. The IAF of the BC‐containing particles also increased with total particle size, in a similar manner as for the BC‐free particles, but on a level 1 order of magnitude lower. Furthermore, BC‐containing IR were found to have a thicker coating than the BC‐containing total aerosol, suggesting the importance of atmospheric aging for ice nucleation.

Schlagwörter

Fachgebiet (DDC)

Projekt

Veranstaltung

Startdatum der Ausstellung

Enddatum der Ausstellung

Startdatum der Konferenz

Enddatum der Konferenz

Datum der letzten Prüfung

ISBN

ISSN

2169-897X
2169-8996

Sprache

Englisch

Während FHNW Zugehörigkeit erstellt

Ja

Zukunftsfelder FHNW

Publikationsstatus

Veröffentlicht

Begutachtung

Peer-Review der ganzen Publikation

Open Access-Status

Hybrid

Lizenz

Zitation

KUPISZEWSKI, Piotr, Marco ZANATTA, Stephan MERTES, Paul VOCHEZER, Gary LLOYD, Johannes SCHNEIDER, Ludwig SCHENK, Martin SCHNAITER, Urs BALTENSPERGER, Ernest WEINGARTNER und Martin GYSEL, 2016. Ice residual properties in mixed‐phase clouds at the high‐alpine Jungfraujoch site. Journal of Geophysical Research: Atmospheres. 2016. Bd. 121, Nr. 20, S. 12343–12362. DOI 10.1002/2016jd024894. Verfügbar unter: https://doi.org/10.26041/fhnw-7802

Komplettanzeige