摘要
利用我国西南地区1971—2017年的逐日降水和气温数据对极端降水的变化进行了研究,采用百分位阈值法来定义极端降水,并通过对逐日降水的计算和统计得出6个极端降水指数,经分析发现:从时间上看,近47年来西南地区总降水量减小,但极端降水的频次和强度增大;从空间上看,西南地区东部的极端降水比率和强度都大于西部。此外,夏季平均气温的升高会导致极端降水量的平稳增加,但日平均气温的升高却会导致极端降水量先缓增后骤减,说明西南地区极端降水随温度的升高有更多不确定性的同时极端降水趋于一个频次更高、时间更短、强度更强的趋势发展,极端降水量随夏季平均气温升高的变化率为8.52%/℃,大于C-C方程的理论解。
In this paper,the daily precipitation and temperature data from 1971 to 2017 in Southwestern China were used to study the changes in extreme precipitation.The percentile threshold method was used to define extreme precipitation,and six extreme precipitation indexes were obtained through the calculation and statistics of daily precipitation.After research and analysis,the following conclusions were obtained:from the time point of view,the total precipitation in Southwestern China decreased in the past 47 years,but the frequency and intensity of extreme precipitation have increased.From the spatial point of view,the ratio and intensity of extreme precipitation in the east part of Southwestern China were higher than those in the west part of Southwestern China.The increase in summer averaged temperature will lead to a steady increase in extreme precipitation.Still,the increase of daily average temperature will cause the extreme precipitation to increase slowly and then suddenly decrease,it shows that extreme precipitation in Southwestern China has more uncertainty with the increase of temperature,and extreme precipitation tends to develop in a trend of higher frequency,shorter time,and more vigorous intensity.The change rate of extreme precipitation with summer averaged temperature was 8.52%/℃,which was higher than that of the C-C equation.
作者
汪靖
张少波
袁利平
Wang Jing;Zhang Shaobo;Yuan Liping(Plateau Atmosphere and Environment Key Laboratory of Sichuan Province,Chengdu University of Information Technology,Chengdu 610225;Gongshan County Meteorological Bureau,Nujiang 673500;Nujiang Prefecture Meteorological Bureau,Nujiang 673200)
出处
《气象科技进展》
2021年第6期31-37,共7页
Advances in Meteorological Science and Technology
基金
四川省教育厅重点项目(18ZA0095)
成都信息工程大学引进人才启动项目(KYTZ201737)。
关键词
极端降水
西南
温度
相关性
extreme precipitation
Southwestern China
temperature
correlation
