近45年来河北省极端降水事件的变化研究  

Analysis of Extreme Precipitation Events Change for Hebei Province

作　　者：高霞[1] 王宏 于成文[3] 戴新刚[4] 史丽红[1] 

机构地区：[1]河北省保定市气象局,071000 [2]河北省承德市气象局 [3]河北省气候中心 [4]中国科学院大气物理研究所

出　　处：《气象》2009年第7期10-15,共6页Meteorological Monthly

基　　金：国家重点基础研究发展规划项目(2006CB400504);国家自然科学基金(40775048)资助

摘　　要：利用河北省1961—2005年逐日降水资料,采用通用的极端气候指数,分析了近45年河北省极端降水事件频率变化的时空特征。结果表明,全省平均年最大日降水量呈下降趋势,1980年为由多向少的转折点;强降水日数和暴雨日数变化不大,但南部平原地区一般减少,北部山地区域多有增加,暴雨日数和强度在1990年代中后期显著增加;降水日数有较明显减少,南部和东南部平原减少更显著;降水日数的减少主要是中、小雨(雪)日数减少造成的。这些结果说明,河北省强降水日数和暴雨日数在降水日数中的比重有增大趋势,强降水量和暴雨降水量在总降水量中的比重可能增加了。这种相对增加趋势主要发生在1990年代中期以后。By using daily precipitation data of Hebei Province, from 1961 to 2005 and the extreme precipitation indices developed by WMO/CCL and CLIVAR, the temporal and spatial characteristics of change of extreme precipitation events in the province were analyzed. Results show that the average maximum one-day precipitation undergoes a decreasing trend, especially in the south of Hebei Plain, with 1980 being the abrupt year; Days with intensive precipitation as defined by R95% and heavy precipitation as defined by RMH more or less remain unchanged over the period analyzed, in spite of the fact that the stations of northern Hebei Plateau generally witness an increase, and those of the south a decrease; An obvious upward trend of days with intensive and heavy precipitation exists in late 1990s. The results indicate that average maximum one-day precipitation, days with precipitation and annual precipitation amount experience similar trends of decrease, but extreme precipitation events including days with intensive and heavy precipitation see no significant change. These imply that the proportion of the extreme precipitation events in the total precipitation days, and probably the proportion of extreme precipitation amount in the total annual precipitation, might increase over period 1961 -2005 in the province. The increase dominantly occurs after mid 1990s.

关 键 词：降水日数 极端降水指数 极端降水 

分 类 号：P532[天文地球—古生物学与地层学] P458[天文地球—地质学]