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大气CO2浓度增加,大气辐射平衡调整,将影响到大气的辐射加热,对季风环流的产生影响.CMIP6结果显示,大气CO2浓度增加,可减弱季风区主雨季对流层高,低层的辐射加热,加强对流层中层的辐射加热.各季风区加热响应的峰值层次不同:亚洲季风区平均层次最高(500-775 hPa),北非,南美,澳洲季风区次之(550-600 hPa),北美(600hPa)和南非季风区(600-775 hPa)较低.各季风区水云的垂直分布及其长波辐射效应的变化是形成峰值层次差异的主因.“,”Based on the 1％CO2 experiment of CMIP6,in response to increasing CO2,the summer-mean radiative heating (RH) over the global monsoon area (MA) generally features an increasing response in the mid-troposphere and a decreasing response in the lower and upper troposphere.The pressure level of the maximum RH increase over the Asian MA is the highest and largest in range (500-775 hPa);the maximum increases over the North African,South American,and Australian MA are at 550-600 hPa;throughout the North American MA,the maximum heating increase is at 600 hPa;and the levels of the maximum over South Africa are 600 and 775 hPa.For most of the global MA,the maximum enhancement of RH is at 500,550,and 600 hPa.It is mainly led by the increase in cloud water at and above the maximum level and the decrease in cloud water below,which leads to similar changes in total cloud mass.Because of the longwave heating (cooling) effect at the cloud base (top),the RH enhancements peak at those levels.For the northeast part of the Asian MA and southeast part of the South African MA,RH enhancement peaks at 700 and 775 hPa,mainly attributable to the cloud water reduction below.The reduction leads to similar changes in total cloud.Due to the longwave cooling effect at the cloud top,the reduction contributes to the RH enhancement at the corresponding maximum levels.