黑龙江省夏季干旱气候特征及成因分析

Climatic characteristics and cause of summer drought in Heilongjiang Province

利用1954-2009年气候实测资料,分析了黑龙江省干旱发生的气候特征。结果表明,20世纪70年代与21世纪初的近10年为干旱盛行时期,尤其是2000年后至今,平均每2年发生一次干旱。大部分年份的干旱发生在拉尼娜事件或赤道东太平洋为冷水位相,副高较弱及偏东和北界偏北。从500hPa环流特点表明,东亚区盛行"-、+、-"距平场型式;冷空气偏向乌拉尔北部泰米尔至新地岛,黑龙江处在西风带高脊或高脊与副高结合体控制之下,维持高温少雨造成干旱。选取副高强、厄尔尼诺发生的年份的干旱典型年2004年。恰与过去年份发生的低温多雨形势相反,盛行"-、+、-"距平场型式,造成干旱。从旱年的水汽输送环境来看,来自欧亚大陆40°～50°N与孟加拉弯和南海的水汽输送通道,明显减弱或消失。

Based on the actual climate monitoring data during 1954 -2009 ,we analyzed the climate characteristics of drought in Heilongjiang Province,The 1970s and recent 10 years at the beginning of the century, drought has pre- vailed in the province especially since the year 2000, the drought has happened once every 2 years on average. In most years drought occurred in Lanena event or eastern Pacific equator cold water level phase;the subtropical high is weaker,easterly and north by north part. 500hPa circulation characteristics show that east asia region prevails ＂ - , ＋ , - ＂ anomaly field, the cold air stants to Tamil-Xingdi island of northern Urals, Heilongjiang Province is under control of high ridge of west wind zone or its association with subtropics, and maintains high temperature cau- sing drought.