安徽省极端降水演变规律及与气候因子遥相关研究  

Spatio-temporal evolution of extreme precipitation and their teleconnection with climate factors in Anhui Province

作　　者：姚蕊 杨惠琳 张书亮[2] 苑倩玉 于世芳 YAO Rui;YANG Huilin;ZHANG Shuliang;YUAN Qianyu;YU Shifang(Key Laboratory of Environmental Change and Natural Disaster,Ministry of Education,Beijing Normal University,Beijing 100875,China;School of Geography,Nanjing Normal University,Nanjing 210023,Jiangsu,China;School of Geography and Tourism,Anhui Normal University,Wuhu 241002,Anhui,China)

机构地区：[1]北京师范大学环境演变与自然灾害教育部重点实验室,北京100875 [2]南京师范大学地理科学学院,江苏南京210023 [3]安徽师范大学地理与旅游学院,安徽芜湖241002

出　　处：《水利水电技术（中英文）》2024年第1期62-73,共12页Water Resources and Hydropower Engineering

基　　金：国家自然科学基金(42271483,4207136);北京师范大学环境演变与自然灾害教育部重点实验室2021年开放课题;安徽省自然科学基金优青项目(2108085Y13);安徽省重点研究与开发计划项目(2022m07020011,2021003);安徽高校协同创新资助项目(GXXT-2021-048)。

摘　　要：【目的】随着全球气候变暖,极端降水事件强度和频率呈显著增加趋势,强降水引起的洪涝灾害不仅对社会经济造成严重的损失,还对生态环境带来极大破坏。2020年安徽省遭受持续时间长和降雨量大的特强梅雨降水过程,造成安徽省受灾严重。【方法】利用气象站点观测降水数据和ERA5再分析数据,探究安徽省极端降水时空演变特征和典型小时尺度降水过程,分析其与气候因子的遥相关关系。【结果】结果显示:1960—2020年安徽省6月和7月平均PRCPTOT变化率为9.0 mm/10 a和8.0 mm/10 a。2020年梅雨期影响范围最大的四次降水事件,累计雨量超过100 mm的气象站数占比达34%以上。相比1998年和2016年,2020年安徽省6—7月平均PRCPTOT为900.56 mm,是1960年以来最大值,是1998年和2016年的1.9倍和1.5倍;降雨强度(25.37 mm/d)为2016年的1.2倍、1998年的1.1倍,是历史均值的1.4倍。【结论】研究结果表明:(1)安徽省主汛期极端降水显著增加,且主要中心位于长江以南。极端降水量、降水强度、降水日数均增加。2020年强降水主要分布在长江河谷和皖南山区,降水主要发生在夜间和清晨;安徽北部地区降水更加集中,主要出现在下午,在15:00达到最大值。(2)与1998年和2016年相比,2020年安徽省降水总量、中雨以上日数和连续降水期明显增加。在降水强度相同的情况下,2020年中雨和大雨日数发生次数多,且连续降水期更长,是2020年6—7月降水量高的最主要原因。(3)安徽省6—7月极端降水指数与PDO在滞后3个月尺度上正相关性最显著,而滞后6个月尺度上极端降水指数与气候因子的正相关性不显著,SOI在滞后1个月(6个月)尺度上与极端降水指数呈正(负)相关性显著。[Objective]The intensity and frequency of extreme precipitation events due to global warming are increasing significantly.Regional floods and urban waterlogging disasters caused by heavy precipitation have brought serious losses to the ecological environment and social economy.In 2020,Anhui Province has been affected by the long duration and heavy rainfall of the super-strong Meiyu precipitation process,causing floods in all rivers basin in Anhui Province.[Methods]In this study,we have used the observed precipitation data and ERA5 reanalysis data to calculation extreme precipitation index,explored the temporal and spatial characteristics of extreme precipitation,and analyzed its teleconnection relationship with climatic factors.[Results]The result show that the average PRCPTOT increased by 9.0 mm and 8.0 mm per decade in June and July from 1960 to 2020.In the four precipitation events with the largest impact during the Meiyu period in 2020,the number of meteorological stations with precipitation exceeding 100 mm accounted for more than 34%.Moreover,average June-July precipitation in Anhui Province in 2020(900.56 mm)reached a record high,1.9 times and 1.5 times higher than in 1998 and 2016.Besides,rainfall intensity(25.37 mm/d)was 1.2 and 1.1 times higher than in 2016 and 1998,and 1.4 times higher than the historical average.[Conclusion]The result show that(1)the extreme precipitation has a significantly increasing trend in the main flood season in Anhui Province,and the center is located in the south of the Yangtze River.The heavy precipitation in 2020,occur at night and early morning,is mainly distributed along the Yangtze River and in the mountainous areas of southern Anhui.While the precipitation in the northern part of Anhui occur in the afternoon(15:00).(2)Compared with 1998 and 2016,PRCPTOT,R10,R25 and CWD in 2020 have increased significantly.Under the same rainfall intensity,the heavy precipitation in June-July 2020 is mainly attributed to the significant increase of R25 and CWD.(3)The positive correlation

关 键 词：极端降水 时空特征 气候因子 遥相关 安徽省 气候变化 降雨 

分 类 号：P426.6[天文地球—大气科学及气象学]