气候变化领域集成服务门户(CCPortal): Anthropogenic aerosol effects on tropospheric circulation and sea surface temperature (1980-2020): Separating the role of zonally asymmetric forcings

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DOI	10.5194/acp-21-18499-2021
	Anthropogenic aerosol effects on tropospheric circulation and sea surface temperature (1980-2020): Separating the role of zonally asymmetric forcings
	Diao C.; Xu Y.; Xie S.-P.
发表日期	2021
ISSN	1680-7316
起始页码	18499
结束页码	18518
卷号	21 期号:24
英文摘要	Anthropogenic aerosols (AAs) induce global and regional tropospheric circulation adjustments due to the radiative energy perturbations. The overall cooling effects of AA, which mask a portion of global warming, have been the subject of many studies but still have large uncertainty. The interhemispheric contrast in AA forcing has also been demonstrated to induce a major shift in atmospheric circulation. However, the zonal redistribution of AA emissions since start of the 20th century, with a notable decline in the Western Hemisphere (North America and Europe) and a continuous increase in the Eastern Hemisphere (South Asia and East Asia), has received less attention. Here we utilize four sets of single-model initial-condition large-ensemble simulations with various combinations of external forcings to quantify the radiative and circulation responses due to the spatial redistribution of AA forcing during 1980-2020. In particular, we focus on the distinct climate responses due to fossil-fuel-related (FF) aerosols emitted from the Western Hemisphere (WH) versus the Eastern Hemisphere (EH). The zonal (west to east) redistribution of FF aerosol emission since the 1980s leads to a weakening negative radiative forcing over the WH mid-to-high latitudes and an enhancing negative radiative forcing over the EH at lower latitudes. Overall, the FF aerosol leads to a northward shift of the Hadley cell and an equatorward shift of the Northern Hemisphere (NH) jet stream. Here, two sets of regional FF simulations (Fix_EastFF1920 and Fix_WestFF1920) are performed to separate the roles of zonally asymmetric aerosol forcings. We find that the WH aerosol forcing, located in the extratropics, dominates the northward shift of the Hadley cell by inducing an interhemispheric imbalance in radiative forcing. On the other hand, the EH aerosol forcing, located closer to the tropics, dominates the equatorward shift of the NH jet stream. The consistent relationship between the jet stream shift and the top-of-atmosphere net solar flux (FSNTOA) gradient suggests that the latter serves as a rule-of-thumb guidance for the expected shift of the NH jet stream. The surface effect of EH aerosol forcing (mainly from low-to midlatitudes) is confined more locally and only induces weak warming over the northeastern Pacific and North Atlantic. In contrast, the WH aerosol reduction leads to a large-scale warming over NH mid-to-high latitudes that largely offsets the cooling over the northeastern Pacific due to EH aerosols. The simulated competing roles of regional aerosol forcings in driving atmospheric circulation and surface temperature responses during the recent decades highlight the importance of considering zonally asymmetric forcings (west to east) and also their meridional locations within the NH (tropical vs. extratropical). © 2021 Chenrui Diao et al.
语种	英语
scopus关键词	aerosol; anthropogenic source; atmospheric circulation; atmospheric forcing; sea surface temperature; source apportionment; zonal wind; Eastern Hemisphere; Western Hemisphere
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/246351
作者单位	Department of Atmospheric Sciences, Texas AandM University, College Station, TX 77843, United States; Scripps Institution of Oceanography, University of California, San Diego, CA 92093, United States
推荐引用方式 GB/T 7714	Diao C.,Xu Y.,Xie S.-P.. Anthropogenic aerosol effects on tropospheric circulation and sea surface temperature (1980-2020): Separating the role of zonally asymmetric forcings[J],2021,21(24).
APA	Diao C.,Xu Y.,&Xie S.-P..(2021).Anthropogenic aerosol effects on tropospheric circulation and sea surface temperature (1980-2020): Separating the role of zonally asymmetric forcings.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(24).
MLA	Diao C.,et al."Anthropogenic aerosol effects on tropospheric circulation and sea surface temperature (1980-2020): Separating the role of zonally asymmetric forcings".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.24(2021).