青藏高原东南部-川西地区夏季小时极端降水事件特征研究  

Characteristics of Summer Hourly Extreme Rainfall Events in the Region of Southeastern Xizang Plateau-Western Sichuan Basin

作　　者：李若莹 姚秀萍[2,1] LI Ruoying;YAO Xiuping(Chinese Academy of Meteorological Sciences,Beijing 100081,China;China Meteorological Administration Training Centre,Beijing 100081,China)

机构地区：[1]中国气象科学研究院,北京100081 [2]中国气象局气象干部培训学院,北京100081

出　　处：《高原气象》2024年第5期1113-1124,共12页Plateau Meteorology

基　　金：国家自然科学基金项目(42030611);第二次青藏高原综合科学考察研究项目(2019QZKK0105)。

摘　　要：利用2005-2020年6-8月109个测站的小时降水资料,分析了高原东南部-川西地区(28°N-33°N、90°E-105°E)夏季小时极端降水事件的年降水量、发生次数、降水强度和持续时间等指标的时空分布,并进一步探讨了高原东南部-川西地区夏季小时极端降水事件的降水量、降水强度和降水频率的日变化特征。结果表明:高原东南部-川西地区夏季小时极端降水事件的小时极端降水阈值、年降水量、降水强度和持续时间均具有高原东南部地区小、川西地区大的特点,但发生次数反之。高原东南部地区夏季小时极端降水事件的年降水量、发生次数和持续时间整体均呈随时间增加的趋势,但川西地区夏季小时极端降水事件年降水量、发生次数也呈增加的趋势,而持续时间在川西地区的变化并不显著。高原东南部-川西地区夏季小时极端降水事件降水量、降水强度和降水频率的峰值时间呈现自西向东延迟的分布,川西地区的峰值时间比高原东南部地区分别延迟了3h、4h和2h,这种延迟特征在6月降水强度方面最为明显,川西地区比高原东南部地区延迟了11h。然而,高原东南部地区和川西地区小时极端降水事件降水量、降水强度和降水频率的峰值时间均未表现出显著的年际变化。Based on 109 hourly rain-gauge stations from June to August during 2005-2020,the spatial and temporal distribution of annual rainfall amount,occurrence,rainfall intensity,and duration of summer hourly extreme rainfall events in the region of Southeastern Xizang Plateau-Western Sichuan Basin(28°N-33°N,90°E-105°E)are analyzed.Additionally,the diurnal variation of rainfall amount,rainfall intensity,and rainfall frequency during hourly extreme rainfall events in the region of Southeastern Xizang Plateau-Western Sichuan Basin are also explored.Results show that the hourly extreme the rainfall threshold,the annual rainfall amount,the rainfall intensity,and the duration of summer hourly extreme rainfall events in the region of Southeastern Xizang Plateau are lower than those in the region of Western Sichuan Basin,with the occurrence showing the opposite pattern.The annual rainfall amount and occurrence,and duration of summer hourly extreme rainfall events in the region of Southeastern Xizang Plateau increase over time.The annual rainfall amount and occurrence of hourly extreme rainfall events in the region of Western Sichuan Basin also increase,while the duration of hourly extreme rainfall events in the region of Western Sichuan Basin change insignificant.The rainfall amount’,the rainfall intensity’and the rainfall frequency’peak time of the summer hourly extreme rainfall events in the region of Southeastern Xizang Plateau-Western Sichuan Basin exhibit the eastward delayed features,and their peak time in the region of Western Sichuan Basin are 3 h,4 h and 2 h later than those in the region of Southeastern Xizang Plateau,respectively.The most evident delayed feature exists in the rainfall intensity in June,with the peak time in the region of Western Sichuan Basin being 11 hours later than that in the region of Southeastern Xizang Plateau.However,both the Southeastern Xizang Plateau and Western Sichuan Basin regions exhibit insignificant interannual variation in the peak time of the rainfall amount,the rainfall

关 键 词：青藏高原东南部 川西地区 小时极端降水 时空分布 日变化 

分 类 号：P426.6[天文地球—大气科学及气象学]