东亚阻塞高压与我国降水关系的分析及预测

Analysis and Forecasting of Relationship between East-Asia Blocking Situation and Precipitation of China in July

利用1951-2005年资料,采用纬偏距方法定义了7月东亚阻塞高压指数,分析了7月东亚阻塞高压与东亚环流和我国降水的关系,并从大气环流和海温场探讨了7月东亚阻塞高压发展的前期征兆。结果发现：前期2月大西洋上空500 hPa西风环流强度,前期3月鄂霍次克海500 hPa高度,前期秋季10-11月夏威夷海区海温异常变化,对7月东亚阻塞高压建立与否具有显著的指示性,并给出了预测判据。

Using the data from 1951 to 2005 and longitudinal geopotential height departure analysis method to define East-Asia blocking high index in July,the authors analyze the relation between East-Asia blocking high in July,East-Asia circulation and precipitation of China.From atmospheric circulation and sea-surface temperature（SST）field,it has also probed the former period sign of the East-Asia blocking high development of July.It is found that the 500-hPa Atlantic westerly circulation intensity in the former February,the Okhotsk 500-hPa geopotential height in the former March,and the SST abnormality of Hawaii sea area in former period of October to November has good ability to show whether the East-Asia blocking high in July is built up.The reliable forecasting criterion is also presented.