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利用1955-2010年地面气象站积雪深度、降水资料和NCEP再分析资料，采用统计相关，异常指数与相关矢等计算方法，对2010年西南春旱区域性特征、青藏高原积雪视热源特征进行了综合分析，研究了西南春旱典型区域，获得了影响西南地区春季降水的青藏高原积雪视热源关键区。对高原积雪关键区积雪深度与该区域大气视热源的相关性进行了综合分析，发现青藏高原积雪关键区2月的视热源代表性最好。重点分析了青藏高原积雪关键区2月大气视热源与后期西南严重春旱区降水的异常指数年际变化及其相关关系，结果表明，冬季青藏高原积雪关键区积雪浅、整层大气视热源偏高，有利于西南地区春季出现干燥的偏北气流，导致我国西南地区春雨异常偏少。青藏高原积雪关键区视热源对我国西南春旱预测具有明显的指示意义。“,”Using NCEP/NCAR reanalysis data, observational snow depth and precipitation data in China, adopting the statistical correlation model, including anomaly index and the correlation vector calcu- lation method, the regional characteristics of spring drought in Southwest China and the ＇ strong signal＇ of snow cover and heat source in the Qinghai-Xizang Plateau were analyzed. The typical region of spring drought in Southwest China was studied and then the key area of atmospheric apparent heat source of snow cover on the Qinghai-Xizang Plateau was got which in its later stage influenced the spring precipitation over the typical region of spring drought in Southwest China. Through the comprehensive analysis of the corre- lation between the snow depth and the atmospheric apparent heat source in all levels over the ＇strong sig- nal＇ Key area of snow cover on the Qinghai-Xizang Plateau, it is found that February is the precursor ＇strong signal＇ typical month of the snow cold source in the Key area of snow cover on the Qinghai-Xizang Plateau. Through the anomaly index and the correlation vector analysis, the correlation of the annual change of anomaly index between the apparent heat source （Q1） in ＇strong signal＇ typical month （February） in the Key area of snow cover on the Qinghai-Xizang Plateau and spring precipitation in the lat- er period over the area of spring drought in Southwest China were focused on. Then, the relation between the two anomaly index above have a character of ＇anti-phase＇ in annual change is found. The analyzed re- sult showed that when the snow depth on the Qinghai-Xizang Plateau was shallow, the apparent heat source （Q1） in the Key area of snow cover on the Qinghai-Xizang Plateau was high. And this was beneficial for relative dry northerly flow over Southwest China in spring. This also lead to a abnormal less precipita- tion in spring in Southwest China. The atmospheric apparent heat source in all levels over the Key area of snow cover on the Qinghai-Xizang Plateau has a obviously precursory effect to predict the spring drought in Southwest China.