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Title: Source attribution of black carbon and its direct radiative forcing in China

Abstract

The source attributions for mass concentration, haze formation, transport and direct radiative forcing of black carbon (BC) in various regions of China are quantified in this study using the Community Earth System Model (CESM) with a source-tagging technique. Anthropogenic emissions are from the Community Emissions Data System that is newly developed for the Coupled Model Intercomparison Project Phase 6 (CMIP6). Over north China where the air quality is often poor, about 90 % of near-surface BC concentration is contributed by local emissions. Overall, 35 % of BC concentration over south China in winter can be attributed to emissions from north China, and 19 % comes from sources outside China in spring. For other regions in China, BC is largely contributed from nonlocal sources. We further investigated potential factors that contribute to the poor air quality in China. During polluted days, a net inflow of BC transported from nonlocal source regions associated with anomalous winds plays an important role in increasing local BC concentrations. BC-containing particles emitted from East Asia can also be transported across the Pacific. Our model results show that emissions from inside and outside China are equally important for the BC outflow from East Asia, while emissions from China account formore » 8 % of BC concentration and 29 % in column burden in the western United States in spring. Radiative forcing estimates show that 65 % of the annual mean BC direct radiative forcing (2.2 W m −2) in China results from local emissions, and the remaining 35 % is contributed by emissions outside of China. Efficiency analysis shows that a reduction in BC emissions over eastern China could have a greater benefit for the regional air quality in China, especially in the winter haze season.« less

Authors:
ORCiD logo; ; ORCiD logo; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1349152
Grant/Contract Number:
AC05-76RLO1830
Resource Type:
Journal Article: Published Article
Journal Name:
Atmospheric Chemistry and Physics (Online)
Additional Journal Information:
Journal Name: Atmospheric Chemistry and Physics (Online); Journal Volume: 17; Journal Issue: 6; Related Information: CHORUS Timestamp: 2017-03-30 09:13:20; Journal ID: ISSN 1680-7324
Publisher:
Copernicus GmbH
Country of Publication:
Germany
Language:
English

Citation Formats

Yang, Yang, Wang, Hailong, Smith, Steven J., Ma, Po-Lun, and Rasch, Philip J. Source attribution of black carbon and its direct radiative forcing in China. Germany: N. p., 2017. Web. doi:10.5194/acp-17-4319-2017.
Yang, Yang, Wang, Hailong, Smith, Steven J., Ma, Po-Lun, & Rasch, Philip J. Source attribution of black carbon and its direct radiative forcing in China. Germany. doi:10.5194/acp-17-4319-2017.
Yang, Yang, Wang, Hailong, Smith, Steven J., Ma, Po-Lun, and Rasch, Philip J. Thu . "Source attribution of black carbon and its direct radiative forcing in China". Germany. doi:10.5194/acp-17-4319-2017.
@article{osti_1349152,
title = {Source attribution of black carbon and its direct radiative forcing in China},
author = {Yang, Yang and Wang, Hailong and Smith, Steven J. and Ma, Po-Lun and Rasch, Philip J.},
abstractNote = {The source attributions for mass concentration, haze formation, transport and direct radiative forcing of black carbon (BC) in various regions of China are quantified in this study using the Community Earth System Model (CESM) with a source-tagging technique. Anthropogenic emissions are from the Community Emissions Data System that is newly developed for the Coupled Model Intercomparison Project Phase 6 (CMIP6). Over north China where the air quality is often poor, about 90 % of near-surface BC concentration is contributed by local emissions. Overall, 35 % of BC concentration over south China in winter can be attributed to emissions from north China, and 19 % comes from sources outside China in spring. For other regions in China, BC is largely contributed from nonlocal sources. We further investigated potential factors that contribute to the poor air quality in China. During polluted days, a net inflow of BC transported from nonlocal source regions associated with anomalous winds plays an important role in increasing local BC concentrations. BC-containing particles emitted from East Asia can also be transported across the Pacific. Our model results show that emissions from inside and outside China are equally important for the BC outflow from East Asia, while emissions from China account for 8 % of BC concentration and 29 % in column burden in the western United States in spring. Radiative forcing estimates show that 65 % of the annual mean BC direct radiative forcing (2.2 W m−2) in China results from local emissions, and the remaining 35 % is contributed by emissions outside of China. Efficiency analysis shows that a reduction in BC emissions over eastern China could have a greater benefit for the regional air quality in China, especially in the winter haze season.},
doi = {10.5194/acp-17-4319-2017},
journal = {Atmospheric Chemistry and Physics (Online)},
number = 6,
volume = 17,
place = {Germany},
year = {Thu Mar 30 00:00:00 EDT 2017},
month = {Thu Mar 30 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.5194/acp-17-4319-2017

Citation Metrics:
Cited by: 4works
Citation information provided by
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