华北汛期降水与青藏高原地表温度的相关分析探讨

Analysis of the Correlation between Tibetan Plateau Surface Temperature and Precipitation over North China During Rainy Season

利用1980～2002年青藏高原月平均地表温度、1957～2002年我国华北地区104站月降水,分析了青藏高原地表温度与华北以及各分区汛期(7、8月)降水的可能联系,结果表明,青藏高原5月地表温度与华北地区汛期降水具有显著的正相关,高相关区域位于高原的东北部和西南部。华北地区汛期降水偏少年,青藏高原5月地温以负距平为主；降水偏多年,青藏高原5月地温为大范围的正距平,距平中心也位于高原的东北和西南部。SVD的分析表明,青藏高原5月地表温度和华北地区汛期降水的第一典型场表现出一致的变化特点,前者的分布型态与华北地区干旱或洪涝对应的合成分布以及相关系数场相似,高值区域分别位于高原的东北部和西南部地区,后者的高值区域,位于华北中部和东部地区。华北不同区域汛期降水与青藏高原地表温度的相关有明显的差异,华北中部和东部与5月高原地温的正相关最显著,其它地区与上年10～12月地温的负相关最显著,同时,影响各分区夏季降水的高原地温关键区也有所不同。

This paper makes a statistic analysis of the possible correlation between Tibetan Plateau surface temperature（TPST） and the precipitation over North China during rainy season （in July and August） by using the datasets of the monthly TPST for 1980-2002 and 104 stations rainfall over North China for 1957-2002. The results show that a striking correlation exists between TPST during May and the precipitations over North China during rainy season with the high anomaly situated in the northeast and southwest areas of Tibetan Plateau. The synthetic analyses indicate that the negative anomaly of TPST occupies a dominant position for drought rainy season over North China, in contrast,the positive anomaly is principal with its maximum located in the northeast and southwest areas of Tibetan Plateau for flood rainy season. The analyses by SVD reveal that the first pairs of singular grounds of TPST in May and the precipitation during rainy season over North China display consistent anomaly change, the former is similar with the synthetic distribution of TPST corresponding to drought or flood years over North China; the latter has the high value regions over the center and east areas of North China. The rainy season precipitation over center and east sub-region both have positive correlation with the TPST in May. But for other sub-regions, the negative correlations with that of previous Oct.-Dec. are dominant. Simultaneously, the key regions of TPST over Plateau affecting the precipitations during rainy season of each sub-region are different.