Inter-decadal variations of springtime rainfall over southern China mainland for 1979–2004 and its relationship with Eurasian snow
Inter-decadal variations of springtime rainfall over southern China mainland for 1979–2004 and its relationship with Eurasian snow
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DOI：
10.1007/s11430-011-4337-4
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发表时间：
2012-01
期刊：
影响因子：
--
通讯作者：
Z. Zuo;Renhe Zhang;Bingyi Wu
中科院分区：
文献类型：
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作者：
Z. Zuo;Renhe Zhang;Bingyi Wu
利用1979-2004年华南春季（3 - 4 - 5月）降水资料，分析了华南春季降水的年代际变化特征。结果表明，在年际和年代际时间尺度上，中国东南部春季降水的变化与中国东南部和西南地区相反。20世纪80年代末，中国南方降水表现出明显的年代际变化。20世纪80年代末以来，中国东南部地区的春季累积降雨量减少了30%，而西南地区的春季累积降雨量增加了两倍。与此变化相关的大气环流表明，亚洲中高纬地区对流层中低层出现异常高压，中国东部地区出现偏强的偏北风。因此，来自热带海洋的湿气流在华南减弱，导致中国东南部降水减少，而西南地区降雨增多。此外，亚洲中高纬度地区的大气环流异常与80年代后期欧亚春雪的年代际下降密切相关，表明80年代后期欧亚春雪的年代际变化可能是中国南方春季降水年代际变化的重要因素。
This study analyzes the inter-decadal variations of rainfall over southern China in spring (March–April–May) using the observed precipitation data for 1979–2004. The result shows that the variations of spring rainfall over southeastern China are opposite to those over and southwestern China in both inter-annual and inter-decadal time scales. The precipitation over southern China exhibits an apparent inter-decadal shift in the late 1980s. The accumulated spring rainfall has reduced 30% over southeastern China after the late 1980s, whereas it has increased twice as much over southwestern China. The atmospheric circulations related to this shift show that an abnormal high at lower and middle troposphere appears over Asian middle and high latitudes, accompanied by stronger-than-normal northerly wind over eastern China. Consequently, the wet air flows from tropical oceans are weakened over southern China, resulting in less rainfall over southeastern China and more rainfall over southwestern China. Furthermore, the anomalous atmospheric circulation over Asian middle and high latitudes is closely related to the inter-decadal downward shift of Eurasian spring snow in the late 1980s, indicating that the inter-decadal shift of Eurasian spring snow in the late 1980s is probably an important factor in the decadal shift of spring rainfall over southern China.