渠江流域短时强降水气候特征分析
Climatic Characteristics of Short-term Heavy Rainfall in Qujiang River Basin
于竹娟 1罗贵东 1夏菲 2程鑫君1
作者信息
- 1. 四川省达州市气象局,达州 635000
- 2. 四川省达州市达川区气象局,达州 635000
- 折叠
摘要
利用 2009-2018年达州、巴中、广安 14个国家基本观测站和 117个区域自动站逐时降水资料,分析渠江流域短时强降水发生频次、小时雨强极值的多尺度时空变化特征.结果表明:(1)除个别年份外,2009-2018年渠江流域≥50 mm/h短时强降水每年发生频次均在 10次以上,特别是 2014年以后呈增加趋势.(2)渠江流域多年平均的短时强降水发生频次月际变化呈单峰型分布,峰值均出现在 7月.(3)渠江流域短时强降水多发生在 02-08时,夜雨特征非常显著,白天随着气温升高在 16时左右有一个次高峰.(4)春季渠江流域短时强降水主要出现在早晨,白天不易出现短时强降水;夏季峰值在 06时前后,白天午后也有一个次峰值,谷值在 19-23时;秋季峰值在早晨,谷值不明显.(5)渠江流域短时强降水平均强度介于 28～29 mm/h之间,2014年以后 40 mm/h以上的短时强降水呈增加趋势.(6)年内最大小时雨强主要出现在 5-9月,7月最多,6月次之.(7)渠江流域下游地区短时强降水发生频次较中上游偏少.
Abstract
Based on the hourly precipitation data of 14 national basic observation stations and 117 regional automatic stations in Dazhou,Bazhong,and Guang'an from 2009 to 2018,this paper analyzes the multi-scale spatial and temporal variation characteristics of short-term heavy precipitation frequency and hourly rainfall intensity extreme value in Qujiang River Basin.The results show that:(1)The frequency of short-term heavy precipitation in the Qujiang River Basin with a precipitation of≥50 mm/h is more than 10 times per year,and there is an increasing trend after 2014.(2)The monthly average number of short-term heavy precipitation events follows a unimodal distribution,with the peak occurring in July.(3)Short-term heavy precipitation mostly occurs from 02:00 to 08:00 with a significant char-acteristic of night rain.During the day,there is a secondary peak around 16:00 with the increase of temperature in the daytime.(4)Short-term heavy precipitation mainly occurs in the morning in spring,and it is not easy to occur during the day.The peak value in summer is around 06:00,and there is also a secondary peak in the afternoon during the day,with a valley value between 19:00 and 23:00.The peak value in autumn is in the morning,and the valley value is not obvious.(5)The average intensity of short-term heavy precipitation is between 28 and 29 mm/h,and there has been an increasing trend of short-term heavy precipitation above 40 mm since 2014.(6)The annu-al maximum hourly rainfall intensity mainly occurs from May to September,with the highest intensity in July and the second highest in-tensity in June.(7)The frequency of short-term heavy precipitation in the lower reaches of the Basin is less than that in the middle and up-per reaches.
关键词
渠江流域/短时强降水/气候/特征Key words
Qujiang River Basin/Short-term heavy precipitation/Climate/Characteristics引用本文复制引用
基金项目
达州市气象局科学技术研究项目(DZQXKJ-201803)
出版年
2024
NETL
NSTL
万方数据