中文摘要：

随着东亚地区经济高速发展,气溶胶成为最主要的大气污染物之一,其时空分布受到东亚季风气候的影响.本研究利用MODIS（Moderate-Resolution Imaging Spectroradiometer）和TOMS（Total Ozone Meteorological Satellite）气溶胶卫星产品以及NCEP（National Centers for Environmental Prediction）月均气象场再分析资料,统计分析了1979—2011年东亚地区气溶胶光学厚度的分布特征以及冬季风的大气环流特征,同时分析了东亚冬季风对气溶胶传输和分布的影响.结果表明,东亚冬季风存在明显的年际和年代际差异,年际变化幅度较大.1979—2011年东亚冬季风出现逐渐减弱的趋势.近10年来东亚地区气溶胶光学厚度呈现上升趋势,主要是由于人类活动导致气溶胶排放量增加.东亚地区冬季风对气溶胶的分布有较大影响,强冬季风年会加强气溶胶的向南输送,同时降水增加导致气溶胶湿清除增大,使东亚气溶胶减少.在风场和降水对气溶胶的影响中,降水的清除作用更加明显.

英文摘要：

With the rapid economic development in East Asia,atmospheric aerosol becomes one of the key air pollutants,whose spatial and temporal distribution was affected by the East Asian monsoon climate.In this study,MODIS and TOMS aerosol products,as well as NCEP reanalysis monthly meteorological field data were used to statistically analyze regional distribution of aerosol optical thickness and atmospheric circulation of winter monsoon between 1979 and 2011in East Asia.Additionally,analysis on the effect of East Asia winter monsoon on the distribution of aerosol were carried out.Investigations showed that the East Asian winter monsoon has strong inter-annual and inter-decadal variations,while inter-annual variation was more significant.In 1979-2011,East Asian winter monsoon exhibits a gradually decreasing trend.Aerosol optical thickness was continuously increasing in East Asia during recent ten years,probably due to enhancement of human activities which could intensify aerosol emissions.East Asia wintermonsoon has significant influence on distribution of aerosol.For instance,strong winter monsoon can reinforce transportation of aerosols to the south area,and increasing precipitation leads to faster wet deposition and less burden of aerosol.It seems that the precipitation scavenging effect is more efficient rather than the wind transport effect.