长三角城市群下垫面变化气候效应的模拟研究

利用法国动力气象实验室发展的高分辨可变网格大气环流模式LMDZ,分别通过LMDZ的高分辨可变网格区域版及其全球版模式的数值模拟,研究长三角城市群下垫面变化带来的夏季气候效应,并尝试探讨大尺度环流的响应.其中LMDZ高分辨区域模式的模拟结果表明长三角城市群下垫面变化可导致夏季长三角地区接受的净辐射明显增加,感热通量上升,潜热通量下降,引起局地地表温度显著上升.同时西太平洋副热带高压西伸北抬控制长三角地区,反气旋性水汽通量异常,导致该地区降水异常减少.进一步对LMDZ全球模式的模拟结果分析,发现长三角城市群下垫面变化可能会引起大气基本模态的变化,进而引起南北半球中高纬异常波列结构的出现.

Numerical simulation of climate effects of urbanization over the Yangtze River Delta

LMDZ global and regional model with two sets of numerical experiments was used to investigate the influence of urbanization over the Yangtze River Delta on East-Asia regional climate and global atmospheric general circulation in summer. The result of the sensible experiments of regional model presents that the land use change (LUC) over Yangtze River Delta may result in the increasing of regional net radiation and sensible heat flux, and the decreasing of latent heat flux, finally, lead to the significant warming of the earth surface; meanwhile, due to the domination of west Pacific subtropical high and the anomaly of anticyclone moisture flux, the precipitation over Yangtze River Delta decreases. The sensible experiments of global model suggested that the LUC over Yangtze River Delta may induce the alternation of basic pattern of global circulation and excite wave trains in the high latitude regions both in Northern and Southern Hemisphere.