【摘要】 利用MERRA-2(第2版现代研究与应用再分析)资料分析了1980-2017年全球硫酸盐、黑碳、有机碳、海盐、沙尘及总气溶胶光学厚度的时空分布特征;选取了北美、北非、南非、印度、中国和印度洋6个典型区域研究了硫酸盐、黑碳、有机碳、海盐和沙尘气溶胶对总气溶胶光学厚度的贡献率。结果表明,硫酸盐、黑碳、有机碳、海盐和沙尘气溶胶在全球非均匀分布,并且具有季节变化;全球总气溶胶的光学厚度(Aerosol Optical Depth,AOD)在夏季最大(0.137),春季次之(0.130),冬季最小(0.118);在6个典型区域里,北非地区总气溶胶的光学厚度最大,为0.43;其次是中国的东部地区,为0.41;每个区域其主要气溶胶的类型并不相同,在北美、中国东部及印度中部地区,硫酸盐是主导的气溶胶类型,贡献率分别为66%,63%和42%,在印度洋、南非及北非地区,海盐、有机碳和沙尘分别是最主要的气溶胶类型,贡献率分别为65%,51%和82%;对于黑碳、硫酸盐和总气溶胶,中国东部地区和印度中部地区有较为明显的增长趋势,其中总气溶胶光学厚度的线性增长率分别为0.007 a-1和0.0056 a-1,但在2010年以后,中国东部地区出现明显的下降。更多还原

【Abstract】 The spatial and temporal distribution of aerosol optical thickness for sulfate,black carbon,organic carbon,sea salt,dust,and total aerosols from 1980 to 2017 was analyzed using MERRA-2;six typical regions were selected to study the contribution of each type of aerosol to total aerosol optical depth.The results show that five types of aerosols are unevenly distributed globally and have seasonal variations;the global total aerosol optical thickness is the largest in summer(0.137),followed by spring(0.130),and the smallest in winter(0.118);in the six typical regions,the largest aerosol optical depth is in North Africa whose value is 0.43,followed by the eastern part of China,which is 0.41;the dominant types of aerosols in each region are different,in North America,Eastern China and Central India,sulfate is the dominant aerosol type with the contribution of 66%,63% and 42% to total AOD,respectively,in the Indian Ocean,South Africa and North Africa,sea salt,organic carbon and dust are the main types of aerosols,respectively,with the contribution of 65%,51% and 82%,respectively.There is a clear growth trend for black carbon,sulfate and total aerosols in Eastern China and central India and the linear trend 0.007 a-1 and 0.0056 a-1 for total aerosol optical depth in Eastern China and central India,respectively,but after 2010 there is a significant decline in Eastern China.更多还原