利用在线耦合的区域气候化学模式系统(R.egCCMS),对2003～2007年的3,4,5月中国沙尘气溶胶的空间分布,间接辐射强迫和间接气候效应进行模拟.结果表明:沙尘分布主要集中在中国西北的新疆、内蒙、甘肃等地区.5月份最高的中心值浓度达到3500.μg/m3,3个月地面浓度依次增大.3,4,5月由沙尘气溶胶造成的第一间接辐射强迫平均值分别为- 1.26,-2.0,-2.69W/m2.局部地区达到-7W/m2.考虑到沙尘气溶胶的第一间接气候效应后,使近地面气温下降,降水减少,3,4,5月地面气温变化的平均值为-0.05,-0.07,-0.08K.3,4,5月降水变化平均值分别为-0.0037,-0.037,-0.1mm/d.不同的月份和地区,温度和降水的变化存在明显的差异.%A regional climate chemistry model system (RegCCMS) was constructed by coupling the regional climate model (RegCM3) with a tropospheric atmosphere chemistry model (TACM). Then it was used to investigate the influence of the spatial distribution of dust aerosol over China in March, April and May during 2003 to 2007, its associated indirect radiative forcing and the climatic effect. The simulated results show that high concentration of dust aerosol was mainly found in Xinjiang, Inner Mongolia, and Gansu Provinces of northwest China. The concentration increases with the time evolution and reaches to 3500 μg/m3 in May. The monthly averaged indirect radiative forcing at the tropopause due to dust aerosol over China is -1.26 in March, -2.0 in April and -2.69 W/tn2 in May. In some regions, a value of -7 W/m2 was simulated. Sensitivity tests showed that the dust aerosol reduces the surface air temperature and precipitation. Mean changes in surface air temperature and precipitation are -0.05K. And -0.0037 mm/d in March, -0.07K. And -0.037 mm/d in April and -0.08K. And -0.1 mm/d in May, respectively. There were significant spatial variations in reductions of surface air temperature and precipitation in the simulations.
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