北疆极端降水事件的区域性和持续性特征分析  

The Feature Analysis of Regional and Persistent Extreme Precipitation Events in Northern Xinjiang Region

作　　者：赵勇[1] 黄丹青[2] 朱坚[2] 杨青[1] 

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002 [2]南京大学大气科学学院,江苏南京210093

出　　处：《冰川冻土》2011年第3期524-531,共8页Journal of Glaciology and Geocryology

基　　金：公益性行业(气象)科研专项(GYHY201006012);国家自然科学基金项目(40675042);中央级公益性科研院所基本科研业务费项目(IDM200804)资助

摘　　要：基于新疆北部1961—2007年43个站点的逐日降水资料,采用百分位方法定义极端降水事件的阈值,分析了北疆地区极端降水事件的区域性和持续性特征.结果表明:春夏秋冬四季,大范围发生极端降水事件的区域分别位于北疆的东北部地区、北部地区、东北部地区和西北部地区以及东南地区,发生持续性较强的极端降水事件的频数大值中心分别集中在伊犁河谷、中东天山地区、北疆西南部和北疆盆地.持续1d的极端降水对总降水贡献四季分布均匀,夏季略高.差异主要表现为由春季到冬季,大值中心呈现出从北疆的东天山地区向中天山和盆地地区移动的趋势.持续2d的极端降水对总降水贡献四季之间差异较显著,一般夏、冬季的较大而春、秋季的则较小.各类持续性极端降水平均强度表明,北疆地区的强降水灾害多数是由持续时间较长的极端降水事件所造成的,四季北疆地区区域平均的持续性极端降水均为显著的线性上升趋势.Based on daily precipitation data from 43 stations in northern Xinjiang Region（NXJ） from 1961 to 2002,the regional and persistent features of extreme precipitation are studied in this paper.The results indicate that： 1） widespread extreme precipitation events taken place in the northeast,the north,the northeast and northwest and the southeast of NXJ,respectively,in the four seasons;2） from spring to winter,the persistent extreme precipitation was concentrated in Ili River valley,the Middle-Eastern Tianshan Mountains,the southwest of NXJ and the basin in NXJ,respectively;3） the contribution of one-day persisting extreme precipitation to the total precipitation was uniform in the four seasons,with a little high in summer.There was a difference mainly in the period from spring to winter,when a maximum moved from the east to the center of the Tianshan Mountains and to the basin in NXJ.There was a remarkable difference of two-day persisting extreme precipitation among the four seasons,larger in summer and winter and less in spring and the autumn;4） average intensity of different persistent extreme precipitation showed that the majority of heavy rainfall disasters were caused by long-term extreme precipitation;5） temporally there was a significant increasing trend of persistent extreme precipitation in NXJ for all seasons.

关 键 词：新疆北部 极端降水 区域性 持续性 

分 类 号：P426.614[天文地球—大气科学及气象学]