2011—2020年德州市短时强降水时空变化特征

Temporal and Spatial Variation Characteristics of Short-Term Heavy Rainfall in Dezhou City from 2011 to 2020

本文利用德州市各县(市、区)2011—2020年4—10月11个国家自动站及76个区域自动站的逐时降水资料,研究德州市降水量超过20 mm/h的时空变化特征,分析其空间分布、年际变化、月变化及日变化特征。结果表明:德州市短时强降水的均次年平均降水量空间分布较为均匀,年平均降水频次的空间分布为南多北少;均次降水量和降水频次年际间呈明显的波动变化;月平均降水量和月平均降水频次以7月、8月最多,10月最少;日变化降水量分布较为均匀,而降水频次日变化分布存在两个明显的大值区域,分别是凌晨和下午时段。

This paper uses the hourly precipitation data of 11 national automatic stations and 76 regional auto⁃matic stations from April to October of 2011—2020 in all counties(county-level cities and districts)of Dezhou city to study the temporal and spatial characteristics of precipitation over 20 mm/h in Dezhou city,and analyzes its spatial distribution,inter-annual variation,monthly variation and daily variation characteristics.The results show that the average annual average precipitation of short-term heavy rainfall in Dezhou city is more evenly distributed,and the average annual precipitation frequency is more in the south and less in the north.The aver⁃age precipitation and precipitation frequency show obvious fluctuations between years.The monthly average precipitation and the monthly average precipitation frequency are the most in July and August,and the least in October.The distribution of daily variation of precipitation is relatively uniform,while the distribution of daily variation of precipitation frequency has two obvious large-value areas,namely the early morning and afternoon periods.