全球和中国地区PM_(2.5)时空变化特征的模拟

利用气溶胶-气候耦合模式BCC_AGCM2.0.1_CUACE/Aero,模拟了1850~1980和1980~2010年PM_(2.5)及其人为和自然气溶胶柱含量的时空变化,并分析了人为和自然气溶胶对这种变化的贡献.结果表明:1850~1980年,大部分陆地范围人为PM_(2.5)的柱含量有所增加,尤其是北美东部、欧洲和中国东部等地区,人为PM_(2.5)增加地更明显,且以夏季最为明显;自然PM_(2.5)的变化主要分布在几大沙漠地区,以春、夏季最为显著;人为气溶胶对总PM_(2.5)变化的贡献在秋季最大,达94%,夏、冬季次之,分别为46%和41%,春季最小,仅占28%.1980~2010年,人为PM_(2.5)在东亚、东南亚等地区均有所增加,春夏季较为显著,在欧洲中部和北美东部有所减少,且以夏季减少最为明显;自然PM_(2.5)在沙漠地带有显著的变化,以春季最为明显;人为PM_(2.5)的变化对总变化的贡献相比之前有所减少,四季均小于50%.

Simulation of global distribution of temporal and spatial variation of PM2.5 concentration

The temporal and spatial variations of the concentration of PM_2.5 from the year 1850 to 1980 and 1980 to 2010, as well as the contributions of anthropogenic and natural aerosols to these variations were simulated in this work, using an aerosol-climate coupled model BCC_AGCM2.0.1_CUACE/Aero. Results show that from 1850 to 1980, the column concentrations of anthropogenic aerosols increased significantly over the globe. The column concentrations of anthropogenic aerosols in PM_2.5 mainly increased in eastern North American, Europe and eastern China, and their changes in summer were more significant than in other seasons. The column concentrations of natural aerosols changed more obviously over several large deserts, and their changes in spring and summer were the most significant of all seasons. Anthropogenic aerosols contributed the largest to the variation of PM_2.5 column concentration in autumn(95%), but in spring their contributions were the smallest(28%), and in summer and winter their contributions were almost equal(46% and 41% respectively). From 1980 to 2010, the column concentrations of PM_2.5 and anthropogenic aerosols increased(especially in spring) in Southeast Asia, while decreased(especially in summer) in Central Europe and North American. Whereas, natural aerosols decreased sharply in desert regions during 1980 to 2010, and their changes were more significant in winter and spring. Variations of natural aerosols almost appear in deserts. The contributions of anthropogenic aerosols to the seasonal change of PM_2.5(less than 50% in all seasons) generally reduced comparing with that from 1850 to 1980.