1961-2013年东北地区夏季极端降水事件变化特征  

Temporal and spatial variability of summer extreme precipitation events in Northeast China during 1961-2013

作　　者：梁丰[1] 刘丹丹[1] 王婉昭 张富荣[1] 于芳健 

机构地区：[1]辽宁省朝阳市气象局,辽宁朝阳122000 [2]辽宁省气象科学研究所,辽宁沈阳110166

出　　处：《干旱区地理》2016年第3期565-572,共8页Arid Land Geography

基　　金：公益性行业(气象)科研专项(GYHY201106016);辽宁省气象局项目(2015SXI01)

摘　　要：利用东北地区84个气象站1961-2013年逐日降水资料,通过线性回归、气候倾向率、Mann-Kendall非参数检验、相关分析和经验模态分解(EMD)等方法,分析了东北地区夏季6个极端降水指数(连续干旱日数(CDD)、连续湿润日数(CWD)、强降水量(R95)、极端降水量(R99)、最大1 d降水量(RX1day)和最大5 d降水量(RX5day))的变化规律。结果表明:近53 a夏季CDD在东北大部都呈增加趋势,气候倾向率达到0.45 d·(10 a)^(-1),而CWD在东北南部地区表现出一定的减少趋势。进一步研究发现,CDD对东北地区夏季旱年异常敏感,而R95、R99和RX5day与东北地区旱涝年都有很好的对应关系。除CDD和CWD外,其它4种极端降水指数与夏季总降水的变化存在很好的一致性,即各极端降水指数的增加(减少)能够反映出降水量的增加(减少)。在近53 a的时间尺度上,除R95和R99外,各极端降水指数都存在显著的准3 a振荡周期。此外,RX1day和RX5day的17 a周期也较为明显,CDD、R95、R99、RX5day还存在30~32 a的长周期变化。Extreme weather events have been paid wide attention in recent years because it is an important aspect in the field of climate change research. Influenced by human activities and environmental changes, extreme weather events have increased significantly in different degrees in global scale. Extreme precipitation has the most typical characterization of extreme weather events, both domestic and overseas scientists have focused on the change of extreme precipitation. Northeast China is very sensitive to climate change;however, research on extreme precipitation index in Northeast China still remains fragmented. Based on daily precipitation data of 84 weather stations in Northeast China from 1961 to 2013, this paper analyzed the features of six extreme precipitation indices over Northeast China by using linear regression, climate tendency, Mann-Kendall nonparametric test, Principal component analysis and Empirical Mode Decomposition （EMD） method. Results show as follows：（1） Consecutive Dry Days （CDD） exhibited significant increase trend during the recent 53 years, while the other five extreme indices showed decrease trend.（2） In 1960s and 1980s, the average of CDD was the lowest, while the Consecutive Wet Days （CWD） was the highest.（3） The variation coefficient of extreme wet day precipitation （R99） was the biggest of all the extreme indexes, while CDD and CWD were the smallest, indicating that R99 was the most unstable index and CDD and CWD were the most stable index in recent 53 years.（4） Except for CDD and CWD, other extreme precipitation indices all had good correlations with total precipitation in summer. （5） Almost all extreme precipitation indices varied with a three-year period except for very wet day precipitation （R95） and extreme wet day precipitation （R99）. In addition, maximum 1-day precipitation （RX1day） and maximum 5-day precipitation （RX5day） had a period of 17 a, and CDD, R95, R99, RX5day had periods between 30 and 32 years. It is well known that

关 键 词：极端降水事件 时空变化 东北地区 

分 类 号：P426.614[天文地球—大气科学及气象学]