Simulating Direct Effects of Dust Aerosol on Arid and Semi-arid Regions Using an Aerosol-Climate Coupled System
- 作者：Shuyun ZhaoHua ZhangSong FengQiang Fu
- 会议时间：2013-10-23
- 关键词：dust aerosol ; arid and semi-arid ; AGCM
- 作者单位：Shuyun Zhao(Chinese Academy of Meteorological Sciences,Beijing,China;Laboratory for Climate Studies,National Climate Center,China Meteorological Administration,Beijing,China)Hua Zhang(Laboratory for Climate Studies,National Climate Center,China Meteorological Administration,Beijing,China)Song Feng(Department of Geosciences,University of Arkansas,Fayetteville,Arkansas,USA)Qiang Fu(Department of Atmospheric Sciences,University of Washington,Seattle,Washington,USA)
- 母体文献：第30届中国气象学会年会论文集
- 会议名称：第30届中国气象学会年会
- 会议地点：南京
- 主办单位：中国气象学会
- 语种：chi
摘要
This work uses an aerosol–climate coupled system to study the direct climatic effects of dust aerosol on global arid (including hyper-arid) and semi-arid regions.Results show that dust aerosol can cause surface cooling over these regions.The cooling effects of dust aerosol are larger in the Northern Hemisphere (NH) than the Southern Hemisphere (SH).This asymmetric cooling forces a thermal meridional circulation between 30°S and 30°N,with air descending (ascending) in the NH (SH),leading to a decrease (increase) in precipitation over the arid and semi-arid regions over the NH (SH).Dust aerosol can decrease the potential evapotranspiration in arid and semi-arid regions mainly by decreasing the net radiation flux at the top of the atmosphere,which compensates for the decrease in precipitation caused by dust aerosol.Therefore,as the dominant aerosol in the arid and semi-arid regions,dust aerosol does not exacerbate the aridity over most of these regions.The effects of dust aerosol are indiscernible in the expansion of arid and semi-arid areas on a global scale.