青藏高原对东亚夏季风影响的数值模拟  

Numerical simulation of the influence of Tibetan Plateau on east asian monsoon

作　　者：张晨[1] 韩佳芮[2] 李聪 王子谦[4] 

机构地区：[1]中国海洋大学,青岛266100 [2]中国气象局发展研究中心,北京100081 [3]南京市气象局,南京210009 [4]中国科学院大气物理研究所LASG,北京100029

出　　处：《地球物理学进展》2012年第6期2322-2334,共13页Progress in Geophysics

基　　金：国家自然科学基金项目(40775069)资助

摘　　要：本文基于大气环流模式CAM,对青藏高原大地形进行简单处理并积分15年,在月和候时间尺度上对比分析了东亚夏季风对高原的响应特征.模式模拟结果表明:高原的隆升加强偏北风,使热带季风爆发之前华南及长江流域的降水加强,并通过对高层大气的显著加热作用,强化了东亚地区上层大气的南北热力差异,使得东亚夏季风加强.在西南风引导下,暖湿气流北上并使长江及江淮流域梅雨期提前,雨量加大且持续时间更长,进而使太平洋副热带高压位置偏西,并改变了东部沿海地区的降雨分布,使其呈现出旱涝相间分布的状况.自7月上旬,高原的存在反而减弱了北方雨季的降雨强度,但是延长了北方降雨期.同时由于降雨释放潜热减少与偏南风加强的作用相互消减,使得337.5假相当位温线到达最北时的位置变化不大.hrough simply changing terrain of the Tibetan Plateau and integrating for 15 years in CAM model,this study compares and analyzes the impact of the plateau on the East Asian monsoon in the month and pentad scale.The results show that： the uplift of Tibetan Plateau enhances northerly winds and rainfall in south China and Changjing river area before tropical monsoon.Through heating upper atmosphere significantly,the thermal difference between land and sea is strengthened,which makes the east Asian monsoon stronger.With the sourthwest wind transporting moisture to Changjiang and Jiang-huai river area,rainy seasons are earlier and last longer,which cause sub-tropical high farther western and change the distribution of monsoon rainfall.The results also show that： since July,there are less rainfall along coastal areas over north China in Tibetan experiment.Meanwhile,since there are less latent heat and more southerly air flow,the position of 337.5 °K pseudo-equivalent temperature line changes little.

关 键 词：CAM模式 东亚季风 青藏高原 

分 类 号：P461[天文地球—大气科学及气象学]