长江中下游地区近60a降水变化规律研究  

Study on the variation of precipitation in the middle-lower reaches of the Yangtze River in recent 60 years

作　　者：张峻[1] 张艺玄 ZHANG Jun;ZHANG Yixuan(Hubei Meteorological info.& Tech.Support Center,Wuhan 430074;School of Applied Meteorology,Nanjing University of Information Engineering,Nanjing 210044)

机构地区：[1]湖北省气象信息与技术保障中心,武汉430074 [2]南京信息工程大学应用气象学院,南京210044

出　　处：《暴雨灾害》2019年第3期259-266,共8页Torrential Rain and Disasters

摘　　要：利用1958—2017年长江中下游地区426个国家站逐日降水资料,通过线性趋势分析法、EOF分解法,使用五个降水特征量,分析了60a来长江中下游地区降水的变化规律。结果表明:(1)长江中下游地区年降水量呈上升趋势,线性趋势为2.21mm·a^-1,夏季的线性趋势为2.03mm·a^-1,冬季雨量略增,而春、秋两季雨量略减;(2)年降水日数的线性趋势为-0.46d·a^1,春、秋、冬三季降水日数均有减少,夏季持平;(3)降水强度呈弱上升趋势,降水强度的高值中心在江西以东大部以及湖北东部、安徽南部边缘,夏季的降水强度最大,冬季的最小,四季的降水强度均有弱增加趋势;(4)降水变异系数的高值中心位于安徽西北部边缘,最高值为0.25,低值中心位于湖南西部,最低值为0.14;春季的降水变异系数最低,夏季整体稳定,秋冬两季的波动性较大;(5)以年降水量作为指标可以把长江中下游地区划分为三种空间分布型,即长江中下游流域区域一致型、长江中下游北部和南部南北反相变化空间型以及长江中下游东部和西部东西反相变化空间型。Based on daily precipitation data at 426 national stations in the middle and lower reaches of the Yangtze River from 1958 to 2017,the variation of precipitation during the recent 60 years is analyzed by linear trend analysis,EOF decomposition and fives precipitation characteristic variables.The results are as follows.(1)The linear trend rate of annual precipitation in the middle and lower reaches of the Yangtze River is 2.21 mm·a^-1,while the trend rate in summer is 2.03 mm·a^-1.Rainfall in winter increases slightly,while the precipitation in spring and autumn decreases slightly.(2)The linear trend rate of annual precipitation days is-0.46 d·a^-1.while the precipitation days in spring,autumn and winter are all decreased,and is flat in summer.(3)The precipitation intensity shows a weak upward trend.The high value centers of the precipitation intensity are in the east of Jiangxi province,the eastern part of Hubei province,and the southern edge of Anhui province.The precipitation intensity is the highest in summer,and the lowest in winter.The precipitation intensity has a weak increasing trend for all four seasons.(4)The high value center of the coefficient of variation of precipitation is located at the edge of northwestern of Anhui province and the highest value is 0.25.The center of its low value is located in the western part of Hunan and the lowest value is 0.14.The coefficient of variation of precipitation in spring is the lowest,stable in the whole summer,and the fluctuation is large in autumn and winter.(5)The area of the middle and lower reaches of the Yangtze River can be divided into three spatial distribution types with annual precipitation as the index,i.e.,the regional consistent pattern of the middle and lower reaches of the Yangtze River,the spatial pattern where precipitation in the northern and southern regions of the middle and lower reaches of the Yangtze River varies inversely,and the spatial pattern where precipitation in the east and west regions of the middle and lower reaches of the Yangt

关 键 词：长江中下游地区 降水特征 线性趋势分析 经验正交分解法 

分 类 号：P467[天文地球—大气科学及气象学]