唐山地区汛期降水日变化特征分析

Diurnal variation characteristics of precipitation in flood season in Tangshan area

根据2010-2019年唐山地区11个气象观测站逐时降水资料,对唐山汛期降水的日变化特征进行分析。结果表明:(1)唐山地区汛期降水频率和降水强度均呈现双峰型的日变化特征,其中,06∶00降水频率最高,凌晨1时降水强度最大。(2)汛期降水以局部降水为主,其中6月局部降水发生概率最高;7、8、9月全区性降水发生概率相对较高,但仍以局部降水为主;区域性降水在各月差异不明显。(3)近10年来唐山地区白天局部降水和区域性降水发生次数显著性增加,导致各站降水频率和降水强度白天呈增强趋势,而区域性降水和全区性降水在夜间发生次数降低,导致夜间降水强度和降水频率呈减小趋势。

Based on the hourly precipitation data of 11 meteorological observation stations in Tangshan from 2010 to 2019,the daily variation characteristics of the precipitation in the flood season of Tangshan are analyzed.The results show that:(1)the frequency and intensity of the precipitation in the flood season of Tangshan are bimodal,among which the precipitation frequency is the highest at 6:00 in the morning and the precipitation intensity is the highest at 1:00 in the morning.(2)The precipitation in flood season is mainly local precipitation,and the probability of local precipitation in June is the highest;the difference of regional precipitation is not obvious in each month.(3)In the past 10 years,the number of local precipitation and regional precipitation increased significantly,which led to the increase of precipitation frequency and precipitation intensity of each station in the daytime,while the number of regional precipitation and regional precipitation decreased at night,which led to the decrease of precipitation intensity and frequency at night.