Effects of long-range aerosol transport on the microphysical properties of low-level liquid clouds in the Arctic

Author(s)
Quentin Coopman, Timothy J. Garrett, Jérôme Riedi, Sabine Eckhardt, Andreas Stohl
Abstract

The properties of low-level liquid clouds in the Arctic can be altered by long-range pollution transport to the region. Satellite, tracer transport model, and meteorological data sets are used here to determine a net aerosol-cloud interaction (ACInet) parameter that expresses the ratio of relative changes in cloud microphysical properties to relative variations in pollution concentrations while accounting for dry or wet scavenging of aerosols en route to the Arctic. For a period between 2008 and 2010, ACInet is calculated as a function of the cloud liquid water path, temperature, altitude, specific humidity, and lower tropospheric stability. For all data, ACInet averages 0.12 ± 0.02 for cloud-droplet effective radius and 0.16 ± 0.02 for cloud optical depth. It increases with specific humidity and lower tropospheric stability and is highest when pollution concentrations are low. Carefully controlling for meteorological conditions we find that the liquid water path of arctic clouds does not respond strongly to aerosols within pollution plumes. Or, not stratifying the data according to meteorological state can lead to artificially exaggerated calculations of the magnitude of the impacts of pollution on arctic clouds.

Organisation(s)
Department of Meteorology and Geophysics
External organisation(s)
University of Utah, Laboratoire d'Optique Atmosphérique, Université Lille I - Sciences et Technologies, Norwegian Institute for Air Research
Journal
Atmospheric Chemistry and Physics
Volume
16
Pages
4661-4674
No. of pages
14
ISSN
1680-7316
DOI
https://doi.org/10.5194/acp-16-4661-2016
Publication date
04-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
105206 Meteorology
ASJC Scopus subject areas
Atmospheric Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/effects-of-longrange-aerosol-transport-on-the-microphysical-properties-of-lowlevel-liquid-clouds-in-the-arctic(915af0a4-292d-489b-87f9-63753d9d1526).html