 |
| Titel |
Quantifying sources, transport, deposition, and radiative forcing of black carbon over the Himalayas and Tibetan Plateau |
| VerfasserIn |
R. Zhang, H. Wang, Y. Qian, P. J. Rasch, R. C. Easter, P.-L. Ma, B. Singh, J. Huang, Q. Fu |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 15, no. 11 ; Nr. 15, no. 11 (2015-06-08), S.6205-6223 |
| Datensatznummer |
250119793
|
| Publikation (Nr.) |
 copernicus.org/acp-15-6205-2015.pdf |
|
|
|
|
|
| Zusammenfassung |
| Black carbon (BC) particles over the Himalayas and Tibetan Plateau (HTP),
both airborne and those deposited on snow, have been shown to affect
snowmelt and glacier retreat. Since BC over the HTP may originate from a
variety of geographical regions and emission sectors, it is essential to
quantify the source–receptor relationships of BC in order to understand the
contributions of natural and anthropogenic emissions and provide guidance
for potential mitigation actions. In this study, we use the Community
Atmosphere Model version 5 (CAM5) with a newly developed source-tagging
technique, nudged towards the MERRA meteorological reanalysis, to
characterize the fate of BC particles emitted from various geographical
regions and sectors. Evaluated against observations over the HTP and
surrounding regions, the model simulation shows a good agreement in the
seasonal variation in the near-surface airborne BC concentrations, providing
confidence to use this modeling framework for characterizing BC
source–receptor relationships. Our analysis shows that the relative
contributions from different geographical regions and source sectors depend
on season and location in the HTP. The largest contribution to annual mean
BC burden and surface deposition in the entire HTP region is from biofuel
and biomass (BB) emissions in South Asia, followed by fossil fuel (FF)
emissions from South Asia, then FF from East Asia. The same roles hold for
all the seasonal means except for the summer, when East Asia FF becomes more
important. For finer receptor regions of interest, South Asia BB and FF have
the largest impact on BC in the Himalayas and central Tibetan Plateau, while
East Asia FF and BB contribute the most to the northeast plateau in all seasons
and southeast plateau in the summer. Central Asia and Middle East FF
emissions have relatively more important contributions to BC reaching the
northwest plateau, especially in the summer. Although local emissions only
contribute about 10% of BC in the HTP, this contribution is extremely
sensitive to local emission changes. Lastly, we show that the annual mean
radiative forcing (0.42 W m−2) due to BC in snow outweighs the BC
dimming effect (−0.3 W m−2) at the surface over the HTP. We also find
strong seasonal and spatial variation with a peak value of 5 W m−2 in
the spring over the northwest plateau. Such a large forcing of BC in snow is
sufficient to cause earlier snow melting and potentially contribute to the
acceleration of glacier retreat. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|