1961—2015年江西省短历时强降水时空分布特征  

Spatial and temporal variations of short-duration heavy precipitation in Jiangxi during 1961-2015

作　　者：唐传师 许爱华 马锋敏[3] 戴志健 TANG Chuanshi;XU Aihua;MA Fengmin;DAI Zhijian(Nanchang Meteorological Service,Nanchang 330038;jiangxi Meteorological Observatory,Nanchang 330096;Jiangxi Climate Center,Nanchang 330096;Jiangxi Ecologic Meteorology Center,Nanchang 330096)

机构地区：[1]南昌市气象局,南昌330038 [2]江西省气象台,南昌330096 [3]江西省气候中心,南昌330096 [4]江西省生态气象中心,南昌330096

出　　处：《暴雨灾害》2018年第5期421-427,共7页Torrential Rain and Disasters

基　　金：中国气象局气象关键技术集成与应用面上项目(CMAGJ2013M26)

摘　　要：利用1961—2015年江西省83个国家级气象观测站逐时降水资料,采用经验正交函数(EOF)和Morlet小波变换等方法,分析江西省短历时强降水时空分布特征,探讨当地短历时强降水与暴雨的关系。结果表明:(1)江西省短历时强降水极值与发生频次分布不匀,呈东多西少分布;全省短历时强降水发生频次变化一致,其中浙赣铁路沿线地区是其频次异常敏感区。(2)近55 a江西短历时强降水频次增加趋势明显,与江西区域性增暖呈正响应关系,该时段短历时强降水频次存在21 a和14 a左右年代际周期变化。(3)江西短历时强降水主要出现在4—9月,6月最多;其日变化4—7月呈双峰型,8—9月呈单峰型,强降水频次在16—17时最多。(4)江西短历时强降水与暴雨空间分布的高频中心相同,其相似系数达0.98;54.6%的短时强降水当日出现暴雨,尤其是凌晨至上午发生的短时强降水当日,暴雨概率高达69.2%~76.9%。Using the hourly rainfall data from 83 national weather stations in Jiangxi from 1961 to 2015, combined with Empirical Orthogonal Function（EOF） and Morlet wavelet analysis, we have analyzed the temporal and spatial distribution characteristics of short-duration heavy precipitation（i.e. larger than or equal to 20 mm per hour） in Jiangxi, and discussed the relation between rainstorm and short-duration heavy precipitation. The results show that both the maximum and frequency of short-duration heavy precipitation show a spatial distribution of high in the eastern and low in the western Jiangxi. Consistent anomaly distribution is a main spatial mode of short-duration heavy precipitation frequency in Jiangxi, whose anomalous sensitive area is located in the places along Zhejiang-Jiangxi railway. In recent 55 years, the frequency of short-duration heavy precipitation has an obvious increasing trend which is positively responding to regional warming of Jiangxi, and it presents two inter-decadal variation periods of about 21 and 14 years. The short-duration heavy precipitation often happens between April and September, and it is the most frequent in June. The diurnal variation of short-duration heavy precipitation shows double-peak distribution between April to July, while single-peak distribution between August and September. The short-duration heavy precipitation occurs the most frequently between 16：00 and 17：00 every day. The high frequency area of short-duration heavy precipitation is similar to that of rainstorm, and their space similarity coefficient reaches 0.98. The short-duration heavy precipitation accompanied with the rainstorm accounts for 54.6%. Especially, the probability of rainstorm is 69.2% to 76.9% from early morning to midday at the day when short-duration heavy precipitation occurs.

关 键 词：短历时强降水 暴雨 小波变换 周期变化 经验正交函数 江西 

分 类 号：P426.6[天文地球—大气科学及气象学]