乌苏市夏季降水日变化特征分析

Analysis of Diurnal Variation Characteristics of Summer Precipitation in Wusu City

摘要: 利用乌苏市2010~2019年逐时降水资料，对夏季(6~8月)降水的日变化特征进行分析，主要结论如下：(1) 乌苏市夏季共出现降水611次，累计降水量485.9 mm。夜间累计降水量是白天降水量的1.5倍，分月来看，6月、7月降水以夜间降水为主，8月昼夜降水持平。(2) 乌苏市夏季逐时累计降水量和降水频次呈现出明显的单峰型特征，高值区均出现在20时至次日02时，峰值均出现在24时，累计降水量为57.0 mm，累计降水频率为53次；降水强度呈明显的波动性，降水强度高值区出现在17~20时，19时降水强度最大，04时最小。(3) ≥0.1 mm、≥1.0 mm、≥5.0 mm降水出现频次整体呈现先上升后下降的趋势，20时至次日02时是各级降水出现频次最高的时段，其中24时、01时出现小量级降水频次最多，23时为小时强降水高发时间。

Abstract: Based on the hourly precipitation data from 2010 to 2019 in Wusu city, the daily variation charac-teristics of precipitation in summer (June to August) are analyzed. The main conclusions are as follows: (1) There are 611 precipitation times in summer in Wusu city, with the cumulative precipitation of 485.9 mm. The accumulated precipitation at night is 1.5 times of that during the day. In terms of months, the precipitation in June and July is mainly at night, while that in August is the same day and night. (2) In summer, the hourly accumulated precipitation and precipitation frequency of Wusu city show a single peak type feature. The high value areas appear from 20:00 to 02:00 of the next day, the peak value appears at 24:00, the accumulated precipitation is 57.0 mm, and the accumulated precipitation frequency is 53 times. The precipitation intensity shows obvious volatility. The high value areas of precipitation intensity appear at 17 - 20:00, 19:00, and 04:00, respectively. (3) The frequency of precipitation ≥ 0.1 mm, ≥1.0 mm, ≥5.0 mm shows a trend of rising first and then falling. From 20:00 to 02:00 of the next day, the frequency of precipitation at all levels is the highest, among which the frequency of precipitation at small level is the most at 24:00 and 01:00, and that of heavy precipitation at 23:00 is the high frequency.