摘要
气溶胶间接效应通过对云的作用来影响气候,其过程复杂且不确定性较大。本研究利用美国国家大气研究中心(NCAR)的公共大气模式CAM5.1,通过改变模式中硫酸盐气溶胶转化为云凝结核数浓度的数量,设计了硫酸盐气溶胶间接效应的敏感性试验,通过与控制试验对比来研究其间接效应对中国东部地区冬季云、降水和季风强度的影响。结果表明:在东亚地区云凝结核形成过程中,硫酸盐气溶胶占绝对的主导地位。硫酸盐气溶胶间接效应导致中国东部地区冬季云凝结核和云滴数浓度显著增加,海洋和陆地低层的云滴有效半径减小和总云液水路径的增加,导致了云反照率的增加。引起的负辐射强迫使地表和大气降温,海平面气压升高,增加的海陆气压梯度导致中国南方地区东亚冬季风增强,总降水率减少。硫酸盐气溶胶间接效应可能不是东亚冬季风在20世纪80年代中期年际变率减弱的原因。
The indirect effects(IE)of aerosols affect the climate through clouds,which is complex and uncertain.Based on the CAM5.1(Community Atmosphere Model,V5.1)model developed by the NCAR(National Center for Atmospheric Research),sensitivity experiments of the IE of sulfate aerosols were designed to investigate the influence of the IE on a cloud,precipitation and the intensity of monsoon in winter in East China in this paper by changing the number concentrations of the sulfate aerosols that can serve as the cloud condensation nuclei number concentration.The results show that sulfate aerosols play a dominant role in the formation of cloud condensation nuclei(CCN)in East Asia.The indirect effects of sulfate aerosols result in a significant increasing concentration of CCN and cloud droplet number in winter in East China,decrease the effective radius of cloud droplet in the low layer of ocean and land,and increase the total cloud liquid water path,resulting in an increasing albedo of a cloud.The negative radiation effect forces to cool the surface and lower atmosphere,increases the sea level press.The increasing sea-land pressure gradient leads to the intensification of the East Asian winter monsoon and the reduction of the total precipitation rate in southern China.The indirect effects of sulfate aerosols may not be responsible for the decadal weakening of East Asian winter monsoon in the mid-1980s.
作者
王东东
朱彬
万绪江
WANG Dong-dong;ZHU Bin;WAN Xu-jiang(Institute of Atmospheric Environment,China Meteorological Administration,Shenyang 110166,China;Key Laboratory of Meteorological Disaster,Ministry of Education,Nanjing University of Information Science&Technology,Nanjing 210044,China;International Cooperative Joint Laboratory on Climate and Environmental Change,Nanjing University of Information Science&Technology,Nanjing 210044,China;Collaborative Innovation Center For Meteorological Disaster Prediction,Warning and Assessment,Nanjing University of Information Science&Technology,Nanjing 210044,China;Key Open Laboratory of Aerosol and Cloud Precipitation,China Meteorological Administration,Nanjing University of Information Science&Technology,Nanjing 210044,China;Liaoning Weather Modification Office,Shenyang 110166,China)
出处
《气象与环境学报》
2020年第5期52-61,共10页
Journal of Meteorology and Environment
基金
国家重点研发计划(2016YFA0602003)
辽宁省自然科学基金(20180540093)共同资助。
