寿光市近56年降水量及雨日雨强变化特征分析

Variation Characteristics of Precipitation, Rain Days and Rainfall Intensity in Shouguang During Recent 56 Years

为了掌握寿光市降水的演变规律,充分利用降水资源,为切实做好气象灾害防御工作提供决策依据。根据寿光市1959—2014年逐日降水资料,利用线性拟合、Mann-Kendall和滑动t等方法,分析了寿光市近56年来降水量、雨日和雨强的变化特征。结果表明:寿光年降水量平均每10年减少12.50 mm,未发生显著突变。日降水量≥0.1 mm、≥1.0 mm的日数减少显著,平均每10年分别减少2.61天和7.83天。日降水量50.0 mm以下的降水日数呈减少趋势,50.0 mm以上降水日数呈不显著微增多趋势。各级降水日数与年降水量多呈显著正相关,日降水量≥10.0 mm的日数与年降水量的相关性最显著。寿光市最长连续降水日数平均每10年减少0.33天,最长连续无降水日数平均每10年增加1.07天。寿光市1日最大降水量和任意15时段降水量均呈不显著略增多趋势,任意1 h、24 h最大降水量分别以3.80 mm/10 a、9.13 mm/10 a的趋势增加,1日最大降水量以3.71 mm/10 a的趋势增加。

The study aims to master evolution law of precipitation in Shouguang, make full use of precipitation resources, and provide decision- making basis for meteorological disaster prevention. Linear fitting, Mann-Kendall, sliding t and other methods were utilized for analyzing the variation characteristics of precipitation,rain days and rainfall intensity in Shouguang during recent 56 years based on daily precipitation data ofShouguang from 1959 to 2014. The results showed that： the annual precipitation decreased by 12.50 mm onaverage per decade in Shouguang without significant mutation. Days with daily precipitation ≥0.1 mm andduration≥1.0 mm reduced significantly by 2.61 days and 7.83 days respectively on average per decade. Therain days with daily precipitation of less than 50.0 mm were decreasing, while the rain days with dailyprecipitation of more than 50.0 mm showed an insignificantly increasing trend. Rain days at all levels weresignificantly and positively correlated with annual precipitation, days with daily precipitation ≥10.0 mm wasmost significantly correlated with annual precipitation. The longest continuous rain days in Shouguangaveragely decreased by 0.33- day per decade, while the longest continuous days without rain averagelyincreased by 1.07- day per decade. 1- day maximum precipitation and arbitrary 15 hours precipitation inShouguang had an insignificantly and slightly increasing trend. 1 hour, 24 hours and 1 day maximum precipitation respectively increased according to the trend of 3.80 mm/10 a, 9.13 mm/10 a and 3.71 mm/10 a.