毕节市短时强降水时空分布特征分析
Characteristics of Spatio-temporal Distribution of Short-time Heavy Precipitation in Bijie City
李文倩 1林雪飞 2蔡军 1张丹 1赵庭飞3
作者信息
- 1. 贵州省威宁彝族回族苗族自治县气象局,贵州 威宁 553100
- 2. 贵州省遵义市气象局,贵州 遵义 563000
- 3. 贵州省织金县气象局,贵州 织金 552100
- 折叠
摘要
[目的]为探究毕节市短时强降水时空分布特征.[方法]利用毕节市2006-2022 年 8 个国家级气象站逐小时降水观测资料,采用统计诊断分析、EOF 等方法对毕节市近 17a短时强降水时空分布与暴雨关系进行研究.[结果](1)2006-2022 年共发生短时强降水 537 站次,年平均 31.6 站次,空间分布东南多、西北少,高发区在织金、纳雍,最少出现在赫章.87.9%的短时强降雨出现在20 mm≤R1h＜40 mm.(2)年际变化呈增长趋势,最大值出现在2019 年(53 站次),最小值出现在2013 年(17 站次);月际变化呈单峰型,5-9 月是短时降水高发时段,7 月达到峰值,主要以局地性单站降水出现;日变化呈单峰型,主要出现夜间,20 时—次日04 时为高发时段,峰值在 02 时.(3)共出现暴雨天气过程 327 次,65.1%的暴雨天气过程伴有短时强降水,7 月暴雨最多,织金暴雨与短时强降水出现最多;暴雨与短时强降水相关性达0.82,暴雨日、伴随短时强降水的暴雨日与短时强降水空间分布均呈东南多、西北少的特征;暴雨日降水量与最大雨强有显著正相关关系.[结论]对了解和认识毕节市短时强降水的气候背景,提升短时强降水防灾减灾能力和临近预报预警能力具有重要意义.
Abstract
Using the hourly precipitation data from eight national meteorological stations in Bijie City from 2006 to 2022,this article analyzes the relationship between the spatio-temporal distribution of short-time heavy precipitation and the rainstorm events in Bijie City from 2006 to 2022 by means of statistical diagnostic analysis and EOF.The results show that:(1)A total of 537 stations/times of short-time heavy precipitation occurred in the last 17 years,with an annual average of 31.6 stations/times,occurring more in the southeast and less in the northwest.Zhijin and Nayong were the places with high occurrence frequency of short-time heavy precipitation,while Hezhang had the least.The hourly rainfall of 87.9%short-time heavy precipitation processes was 20 mm≤R1h＜40 mm.(2)The interannual variation of short-time heavy precipitation shows an increasing trend,with the maximum value of 53 stations/times in 2019 and the minimum of 17 stations/times in 2013.Its inter-monthly variation shows a single-peak pattern,with May-September being the period of high frequency of short-time rainfall,peaking in July,characterized mainly by localized single-station rainfall.Its daily variation shows a single-peak pattern,occurring mainly in the nighttime,with the high frequency between 20∶00 and 04∶00 of the next day and the peak at 02∶00.(3)There were 327 rainstorm processes in total during the 17 years and 65.1%of the rainstorms were accompanied by short-time heavy rainfall,with the most rainstorms in July and the most rainstorms plus short-time heavy rainfall events in Zhijin.The correlation between rainstorms and short-time heavy precipitation amounted to 0.82.The spatial distributions of rainstorm days,rainstorm days accompanied by short-time heavy precipitation,and short-time heavy precipitation were all characterized by more in the southeast and fewer in the northwest.There was a significant positive correlation between the daily precipitation amount of rainstorms and the maximum rainfall intensity.These findings are of great significance for understanding and recognizing the climatic background of short-time heavy precipitation in Bijie City,and for improving the capacity of short-time heavy rainfall prevention and mitigation as well as the capability of nowcasting and early warning.
关键词
短时强降水/暴雨/时空分析/相关性/毕节Key words
short-time heavy precipitation/rainstorm/spatial and temporal analysis/correlation/Bijie City引用本文复制引用
出版年
2024
NETL
NSTL
万方数据