中文摘要：

利用区域气候模式RegCM3， 通过调节夏季青藏高原（下称高原）地区近地层的感热加热强度， 模拟分析了高原热源异常对川渝地区降水的影响， 并探讨了其影响机理。试验结果表明， 高原感热加热异常会导致川渝地区降水发生改变。当高原感热加热减弱时， 四川中部及东部与重庆交界处降水增加， 而川渝其他地区降水明显减少； 当高原感热加热增强时， 降水增加的区域主要是四川西北部和重庆地区， 大值中心出现在重庆南部， 四川西南部和东北部降水减少。高原地区感热加热异常通过影响对流层不同层次的温度场和高度场变化， 引起高原及其周边地区对流层中低层大气环流和水汽输送的变化， 最终诱发川渝地区降水变化。

英文摘要：

In recent years, researches pointed out that the thermal anomaly of Qinghai-Xizang Plateau （QXP） has considerable influence on the precipitation over the Yangtze River Basin, and the previous studies were mainly focused on the middle-lower Yangtze River area. Here, the ICTP Regional Climate Model （RegCM3） were used to analyze the influence of sensible heat anomalies in summer over QXP on the rainfall in Sichuan-Chongqing areas, and reveal the mechanism behind the phenomena in details. In the control test, the original sensible heat （E1） was used, and the 0.5 times and 1.5 times of plateau heat transfer coefficient were used for the two designed sensitive schemes （E2 and E3）, respectively. The experiment results show that： The sensible heat anomalies can cause the changes of the South Asian high and the subtropical high system through the thermal process of adaptation. When the QXP sensible heat in summer decreases （increases）, the South Asia high decreases （increases） and shifts westward （eastward） and northward （southward）. The corresponding 500 hPa west Pacific subtropical high shifts northward （southward） and eastward （westward）. The change of the warm center in upper troposphere and the south Asian high lead to adjustment of the atmospheric circulation in the low lever and change of the water vapor transport, and eventually lead to precipitation anomaly in the Sichuan-Chongqing areas. A cyclonic differential circulation occurs in the eastern plateau for both schemes E2 and E3. When the sensible heat decreased, the center of the cyclonic difference circulation is located in the center of the basin, and westerly air flow occurs in the south of the Sichuan-Chongqing areas, which blocks the water vapor transport from the southwest, and therefore the precipitation in south Sichuan-Chongqing areas decreases. Moreover, the center of the cyclonic differential circulation is located in the eastern basin, which conductive to the increase of precipitation in the eastern basin