夏季青藏高原与热带西太平洋下垫面热源异常对中国短期气候的影响

INFLUENCE OF HEAT SOURCE ANORMAL OF UNDERLYING SURFACE OVER TIBETAN PLATEAU AND WESTERN TROPICAL PACIFIC ON SHORT-TERM CLIMATE IN CHINA

本文利用一个两层全球大气环流格点模式进行了控制试验、青藏高原地表反照率增加及热带西太平洋海温升高等三个数值试验,以研究夏季这两个地区下垫面热源异常对短期气候变化的影响。结果表明,高原地面热源减弱将造成海平面气压场上亚洲大陆低压减弱;高原及其以西地区500 hPa高度下降,黄河以北地区高度升高;同时高原地区、江淮流域以及黑龙江流域降水减少,但从北疆、内蒙到辽河流域以及我国西南局部和东南沿海地区降水增加。热带西太平洋海温异常带来的变化与此不同.文中还就下垫面热源异常在短期气候预测方面的可能应用等问题进行了讨论。

By using a two-level, grid point, global general circulation model, three numerical experiments including the control one, the one with the increase of the surface albedo in Tibetan Plateau as well as the one with the increase of the sea surface temperature (SST) in western tropical Pacific have been conducted in order to investigate the influence of underlying surface heat source abnormal in this paper. The results suggest that when the heat source intensity in the Plateau is reduced by increasing its surface albedo, the continental low at sea level over Asia weatens; the 500 hPa height over the Plateau and to its west side falls, but that in the north of Yellow River rises; the precipitation in the Plateau, the reaches of Yangtse River, Huai He and Hei Long Jiang decreases, but that in the areas from the north Xinjiang and Nei Mongol to the reach of Liao He as well as southwest and southeast part of China increases. When the SST over west tropical Pacific increases, the continental low trough at sea level extending toward east China deepens; the geopotential height from north European to Tajmyr Pennisula rises, but that in north Asia falls; the precipitation in most of west China, Da Hingg An Ling and Mid- and lower-reaches of Yangtse increase, but that of rest China decreases. In addition, the possible application of heat source abnormal of underlying surface to short-range climate in China is also discussed in the paper.