新疆北部夏季强降水分析  

Analysis on Summer Heavy Rainfall in the Northern Xinjiang

作　　者：赵勇[1] 黄丹青[2] 古丽格娜[3] 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 [3]新疆气象局信息中心,新疆乌鲁木齐830002

出　　处：《干旱区研究》2010年第5期773-779,共7页Arid Zone Research

基　　金：中央级科研院所基本科研业务费专项(IDM200804);中国气象局气候变化专项(CCSF-09-20);新疆维吾尔自治区自然科学基金(200821176)联合资助

摘　　要：基于1961-2007年新疆104站的逐日降水资料,分析了新疆北部夏季强降水量、强降水日、强降水比和强降水强度等特征量的气候条件和时间变化。结果表明:新疆北部夏季的强降水各特征量分布存在明显的区域差异。各特征量随地形增高而增多或增强,可能在海拔2000m左右存在最大降水带。局地强降水频繁,平均3～4d就发生一次。北疆夏季强降水事件呈增多、增强趋势,天山山区和伊犁河谷尤为显著。同时,强降水各特征量存在明显的年代际变化,强降水量、强降水日和强降水比自20世纪90年代中后期以来,处在高值期,而强降水强度自1990年后,就处在相对高值期。用Mann-Kendall法对强降水各特征量进行突变检验发现,强降水量、强降水日和强降水比在1995年左右发生了由少到多的气候突变,而强降水强度在1990年和2000年后这种变化趋势表现显著。Xinjiang is a famous arid and semiarid region,and the precipitation occurs mainly in summer.Heavy rainfall is one of the serious meteorological disasters,so the research on heavy rainfall is a key field investigated by meteorologists.Since the 1980s,the extremely meteorological events have been in an increase trend with global warming.Under the background of global climate change,heavy rainfall is possibly becoming as the main contribution to total precipitation.Based on the daily rainfall data observed by 104 meteorological stations in Xinjiang during the period of 1961-2007,in this paper the climatic distribution and the temporal variation of the characteristic parameters of heavy rainfall,i.e.,the volume,occurring days and intensity of heavy rainfall as well as the proportion of heavy rainfall in total precipitation,are analyzed.The results show that the characteristic parameters of heavy rainfall are quite different from different regions in north Xinjiang because of the great disparity of altitude.These characteristic parameters increase or strengthen with the altitude,and there is a maximum rainfall belt around 2000 m a.s.l.Local heavy rainfall occurs frequently and once every 3-4 days in average.The heavy rainfall events are in an obvious increasing and strengthening trend,especially in the Tianshan Mountains and the Yili Valley.Moreover,there is an obvious interdecadal variation of characteristic parameters of heavy rainfall,the volume and occurring days of heavy rainfall as well as the proportion of heavy rainfall in total precipitation are currently the highest since the mid-1990s,but the intensity of heavy rainfall has been the highest since 1990.The sharp changes of the characteristic parameters of heavy rainfall are tested using the Mann-Kendall method,it is found that a sharp change of the volume and occurring days of heavy rainfall as well as the proportion of heavy rainfall in total precipitation occurred around 1995,but that of the intensity of heavy rainfall occurred in 1990,and such trends have

关 键 词：夏季 降水量 降水变化 降水强度 新疆 

分 类 号：P426.6[天文地球—大气科学及气象学]