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高原对我国天气、气候的影响一直以来受到学者的关注，很多研究是围绕高原积雪展开的，然而关于高原积雪影响我国夏季降水的机制尚缺乏统一的认识，这种“隔季相关”的本质以及其具体实现过程仍需要进一步的研究。本文拟利用耦合模式着重分析高原土壤湿度对我国夏季降水的影响机制，通过对地表热源、大气热源的计算，探讨了高原热源与土壤湿度、大气环流之间的关系，结果表明：耦合模式NCAR CCSM3 能够较好地模拟大气环流场等主要特征；高原春季土壤湿度与我国夏季降水有很好的相关，其中以高原土壤湿度对7月的降水影响最为显著，相对而言，中层土壤湿度异常的持续性较好；高原中层土壤湿度异常与表层土壤湿度异常有很好的一致性，可通过影响春末至夏初高原地面状况，改变高原地表热源，进一步影响高原大气的热力作用，影响大气环流形势、我国夏季雨带位置分布，以及江淮地区降水，即：若5月高原中层土壤偏湿，则春末至夏初地面蒸发、潜热通量增加，感热通量、地面温度降低，高原表面的热力作用减弱，使得印度高压西撤偏晚，环流系统的季节性转换偏晚，东亚地区形成有利于我国夏季第I类雨型的环流分布形势，我国东部雨带偏北，华北地区多雨，江淮地区降水偏少，华南地区降水偏多，反之亦然。

Due to the special topographic characterize, Tibetan Plateau (TP) make itself unique plateau climate, and play an important role in the Asian monsoon, atmospheric circulation, further to the globe climate. Many researchers study on its effect from snow, as we know, snow cover over the TP in winter and spring can affect rainfall in China in the following summer, however, the mechanism has been remained to be confirmed for a long time. The coupled model NCAR CCSM3 was employed in this study to investigate how the spring soil moisture resulted from anomalous snow cover over the TP influences summertime precipitation in China. And we also calculated the TP heating to invest the relationship with general circulation, and soil moisture. The results indicate that NCAR CCSM3 can simulated the major characterize of general circulation; the anomalies of top layer soil moisture and middle layer soil moisture have good consistency, but the anomaly of middle layer soil moisture persists longer; the wetter the middle soil moisture over the TP in May, the more the surface evaporation and associated latent heat flux, leading to less surface sensible heat flux and lower surface temperature in early summer; the weaker surface heating over the TP results in weaker heating for atmosphere, and further to a later westward withdraw of the mid-troposphere Indian High and a later seasonal transition of the circulation system over south and east Asia to its summer regime. All of these factors are in favor of the first spatial rainfall pattern of China in summer: more rainfall in North China and South China, but less rainfall in the Yangtze-Huaihe River Basin, and vice versa.