 |
| Titel |
On the relationship between Arctic ice clouds and polluted air masses over the North Slope of Alaska in April 2008 |
| VerfasserIn |
C. Jouan, J. Pelon, E. Girard, G. Ancellet, J. P. Blanchet, J. Delanoë |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 14, no. 3 ; Nr. 14, no. 3 (2014-02-03), S.1205-1224 |
| Datensatznummer |
250118348
|
| Publikation (Nr.) |
 copernicus.org/acp-14-1205-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| Recently, two types of ice clouds (TICs) properties have been characterized
using the Indirect and Semi-Direct Aerosol Campaign (ISDAC) airborne measurements (Alaska, April 2008). TIC-2B were
characterized by fewer (< 10 L−1) and larger (> 110 μm)
ice crystals, and a larger ice supersaturation (> 15%) compared to TIC-1/2A. It has been hypothesized that emissions of
SO2 may reduce the ice nucleating properties of ice nuclei (IN) through
acidification, resulting in a smaller concentration of larger ice crystals
and leading to precipitation (e.g., cloud regime TIC-2B). Here, the origin of
air masses forming the ISDAC TIC-1/2A (1 April 2008) and TIC-2B (15 April
2008) is investigated using trajectory tools and satellite data. Results
show that the synoptic conditions favor air masses transport from three
potential SO2 emission sources into Alaska: eastern China and Siberia
where anthropogenic and biomass burning emissions, respectively, are produced,
and the volcanic region of the Kamchatka/Aleutians. Weather conditions
allow the accumulation of pollutants from eastern China and Siberia over Alaska,
most probably with the contribution of acidic volcanic aerosol during the
TIC-2B period. Observation Monitoring Instrument (OMI) satellite observations reveal that SO2 concentrations in air
masses forming the TIC-2B were larger than in air masses forming the
TIC-1/2A. Airborne measurements show high acidity near the TIC-2B flight
where humidity was low. These results support the hypothesis that acidic
coating on IN could be at the origin of the formation of TIC-2B. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|