近40 a来秦岭及周边地区极端降水变化特征  

Variation characteristics of extreme precipitation in Qinling and surrounding areas over the past 40 years

作　　者：张宏芳 潘留杰[2] 卢珊 沈姣姣 ZHANG Hongfang;PAN Liujie;LU Shan;SHEN Jiaojiao(Shaanxi Meteorological Service Centre,Xi’an 710014,Shaanxi,China;Shaanxi Meteorological Observatory,Xi’an 710014,Shaanxi,China)

机构地区：[1]陕西省气象服务中心,陕西西安710014 [2]陕西省气象台,陕西西安710014

出　　处：《干旱区地理》2024年第3期380-390,共11页Arid Land Geography

基　　金：陕西省重点研发计划(2022SF-360);中国气象局创新发展专项(CXFZ2022J023);陕西省自然基金(S2023-JC-QN-2729)资助。

摘　　要：利用1980—2021年秦岭及周边地区337个气象监测站逐日降水资料,分析了极端降水的时空变化特征,并采用广义极值分布、气候统计等方法,对比了第一阶段(1980—2000年)和第二阶段(2001—2021年)极端降水年及春、夏、秋各季节的差异变化。结果表明:(1)秦岭及周边地区极端降水主要集中在4—11月,其中7月极端降水日数最多,近40 a来极端降水整体呈增加趋势。日极端降水阈值、最大日降水量空间分布呈现东南高于西北,极端降水日数则呈现以秦岭为界,南部多、北部少。(2)从全年角度看,2001—2021年较1980—2000年极端降水事件更多,极端性更强。日极端降水阈值、极端降水日数、最大日降水量的空间变化趋势总体也表现为增多趋势的站点数多于减少趋势的站点数。(3)极端降水季节性差异明显,春季与夏季和秋季呈现出明显的不同。不管是极端降水概率还是极端降水次数,在春季总体表现为1980—2000年极端性更高,而夏季和秋季表现为2001—2021年更强。空间分布季节性差异也较明显,春季日极端降水阈值、极端降水日数总体表现为西部增加东部减小,从西向东表现为由正向负转变的分布,且负趋势站点多于正趋势站点。而夏季和秋季日极端降水阈值、极端降水日数呈增加趋势的站点超过呈减少趋势的站点,特别是秋季增加趋势的站点占比更多。Based on daily precipitation data from 337 meteorological monitoring stations in Qinling Mountains and surrounding areas during 1980—2021,the spatiotemporal characteristics of extreme precipitation were ana-lyzed.The generalized extreme value distribution and climate statistics methods were used to compare the differ-ences in extreme precipitation years and seasons(spring,summer,and autumn)between two phases:the first phase(1980—2000)and the second phase(2001—2021).The results are as follows:(1)Extreme precipitation in Qinling and surrounding areas mainly concentrated from April to November,with July registering the highest number of extreme precipitation days.Over the past 40 years,extreme precipitation has shown an overall increas-ing trend.Spatially,the southeast exhibits higher values for the extreme daily precipitation threshold and daily maximum precipitation than the northwest.Additionally,a clear boundary along the north-south direction,align-ing with the Qinling,highlights more occurrences in the southern region than in the northern region.(2)On an an-nual scale,there is a discernible rise in both the number and intensity of extreme precipitation events during 2001—2021 compared with 1980—2000.The spatial changes in the extreme daily precipitation threshold,the number of extreme precipitation days,and daily maximum precipitation also show an overall increasing trend,with more meteorological stations exhibiting an increasing trend.(3)Considerable seasonal differences in ex-treme precipitation exist,particularly between spring and summer/autumn.The probability and frequency of ex-treme precipitation were generally higher in spring during 1980—2000,whereas in 2001—2021,extreme precipi-tation peaks in summer and autumn.Spatial distribution differences are also evident.In spring,the extreme daily precipitation threshold and the number of extreme precipitation days generally show an increasing trend in the western region,contrasting with a decreasing trend in the eastern region,transitioning from

关 键 词：日极端降水阈值 最大日降水量 极端降水日数 时间变化 

分 类 号：P426.614[天文地球—大气科学及气象学]