利用NCC/CMA资料分析了2008年6月深圳降水异常事件的成因。结果表明, 2007年7月—2008年2月赤道西太平洋海表温度异常偏低、2008年前冬今春青藏高原积雪面积偏大是深圳异常降水事件的前期气候背景; 2008年6月东亚阻塞高压的异常强大及乌拉尔山长波槽的异常加深发展, 促进了经向环流异常增强; 偏强的冷空气以阶梯槽的形式频繁入侵华南, 为深圳异常降水事件提供了动力条件。副高西段较常年偏南、西伸脊点偏东, 强劲的季风潮为深圳地区输送了巨大的水汽和热量, 冷暖空气在深圳繁交汇等, 是深圳异常降水事件的主要成因。上述多种因素的异常共同导致了深圳异常降水事件的发生。

The authors analyze the causes of abnormal rainfall in Shenzhen in June 2008 based on the NCC/CMA data. The results indicate that the abnormally low sea surface temperature in the equatorial western Pacific during July 2007-Februry 2008 and the more spacious snowy area over the Qinghai-Tibet Plateau in the winter before June 2008 were the climatic background of the abnormal rainfall in Shenzhen. Moreover, the blocking high was much stronger in Northeast China and the Urals long-wave trough was abnormally deepening in June 2008, which promoted the meridional circulation. At the same time, much stronger cold air mass outburst in China frequently in the form of ladder troughs, which provided energy for the Shenzhen rainfall. Finally, the subtropical high was stronger and shifted southward, stronger monsoon transmitted huge water vapor and heat, and cold and warm air masses converged in Shenzhen frequently; these were the causes of the abnormal rainfall in Shenzhen. In summary, all the above conditions worked together and resulted in the abnormal rainfall in Shenzhen.