摘要
基于鲁中地区8个气象站1980—2014年逐日降水数据,统计极端降水阈值,并利用线性倾向率、Morlet小波分析和经验正交分解(EOF)等方法分析极端降水的时空变化规律。结果表明:鲁中地区日极端降水阈值为33.2—40.4mm,东北部平原最低,山区最高,日最大降水量由中部地区向南北两侧递增;鲁中地区极端降水日数随时间呈非显著性增加趋势,2002年为突变发生年份,有2年的主要变化周期,主要空间变化规律一致,但在第二特征向量上呈现山区和平原变化的不一致性;年极端降水强度随时间呈增加趋势,1992年为突变年份,年极端降水日数占年降水总日数的5%,贡献了32%的年降雨量;鲁中地区极端降水最早出现在4月,最晚平原地区出现在10月,山区出现在11月,最多出现在7—8月,月际变化的地域差异不大。
Base on the daily precipitation data of eight meteorological stations during 1980-2014 in the middle area of Shandong Province,the thresholds of extreme precipitation is statistically studied,and the temporal and spatial change characters of extreme precipitation is analyzed by using linear trend,Morlet wavelet and empirical orthogonal function(EOF) methods.The results show that the thresholds of extreme precipitation in the middle area of Shandong Province were from 33.2 to 40.4 mm·d^(-1),the lowest is the eastnorth plain,highest in mountain areas,the daily maximum precipitation increased from the center to the north and south sides.The annual extreme precipitation days in the middle area of Shandong Province had a non-significant increase with time,the sudden change appeared in 2002,which had a main period of two years,and its main spatial change was the same,but its second feature vector presented the difference variation between plain and mountain.The annual extreme precipitation intensity had an increase with time,the sudden change appeared in 1992,the annual extreme precipitation days accounted for five percent of the precipitation days,what contributed thirty-two percent precipitation to annual precipitation.The extreme precipitation first appeared in April in the middle area of Shandong Province,which last appeared in October in the plain,November in the mountain areas,and the maximum appeared in the July and August,the monthly variation of extreme precipitation had a non-significant change with regions.
出处
《中国人口·资源与环境》
CSSCI
CSCD
北大核心
2017年第S2期174-177,共4页
China Population,Resources and Environment
基金
山东省气象局气象科学技术研究项目"鲁中地区极端降水事件时空变化特征及暴雨强度公式分区研究"(批准号:2016sdqxm13)
关键词
极端降水
阈值
时空变化规律
地域差异
extreme precipitation
threshold
temporal and spatial change characters
regional difference
