摘要
为更好地了解中亚地区极端降水事件的时空分布特征,利用CPC的逐日降水数据,基于百分位法和极端降水指数研究1983-2022年中亚地区季节极端降水事件的空间特征及其趋势变化,初步探讨极端降水对气温的响应关系。结果表明:极端降水事件具有明显的空间差异和季节差异。(1)极端降水阈值、极端降水平均强度、1日最大降水量在春、秋、冬3个季节均表现为南高北低的空间分布特征,在夏季则表现为北高南低;四季的极端降水日数和持续湿期表现为由西南向东北递增,持续干期与之相反;极端降水贡献率的空间分布在春季和冬季较为均匀,而在夏季和秋季表现为西南低东北高。(2)极端降水日数、极端降水贡献率、持续湿期等在春、秋、冬季均表现正趋势,其中春季信号最强;持续干期在春、冬季表现为减弱趋势。1日最大降水量仅在春季有显著增加趋势。四季极端降水平均强度均无显著的变化趋势。(3)极端降水日数在春季对日最低气温的响应比最高气温更敏感,夏季则与日最高气温呈负相关,秋季和冬季对日最高、最低温度都有显著相关。
To better understand the spatial and temporal features of seasons of extreme precipitation events in Central Asia,using CPC daily precipitation data,the spatial distribution characteristics and the long-term trends of extreme precipitation events over Central Asia in four seasons during 1983-2022 were analyzed based on percentile threshold method and extreme precipitation indices,the responses of extreme precipitation to temperature were also discussed.The results are as follows:The extreme precipitation events have obvious spatial and seasonal differences.(1)The spatial distribution of the threshold and intensity of extreme precipitation and Rxlday all show higher values in the south than in the north in spring,autumn,and winter,while higher values in the north and lower in the south in summer.Both the frequency and CWD gradually increased from the southwest to the northeast in four seasons,while CDD was the opposite.The contribution rate of extreme precipitation is evenly distributed in spring and winter,while displays are low in the southwest and high in the northeast in summer and autumn.(2)The frequency,CWD,and Rxlday of four seasons are generally increasing in spring,autumn,and winter,among which the spring signal was the strongest and the summer trend change was weak;CDD in spring and winter shows a decreasing trend.Rxlday has a significant increase trend only in spring.There is no obvious trend in the intensity of the extreme events in the four seasons.(3)The response of extreme precipitation to the daily minimum temperature is more sensitive than to the maximum temperature in spring,while the frequency is negatively correlated with the daily maximum temperature in summer,and significantly correlated with both maximum and minimum temperature in autumn and winter.
作者
梁雨欣
陈樟
赵勇
刘文丽
LIANG Yuxin;CHEN Zhang;ZHAO Yong;LIU Wenli(College of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610225,China)
出处
《成都信息工程大学学报》
2025年第2期212-219,共8页
Journal of Chengdu University of Information Technology
基金
四川省杰出青年科技计划资助项目(2020JDJQ0050)。
关键词
中亚地区
极端降水
时空分布
变化趋势
温度
季节
Central Asia
extreme precipitation
spatial and temporal distribution
change trend
temperature
seasons
