1991-2020年沈阳市降水趋势变化及突变分析

Analysis of Precipitation Trend Change and Mutation in Shenyang from 1991 to 2020

根据沈阳市1991-2020年逐日降水数据,应用线性回归法、距平百分率法,对沈阳市年、四季、月降水趋势变化特征进行分析;并采用Mann-Kendall法,对年、四季降水量进行突变分析。结果表明:①沈阳市8月份多年平均降水量最高,可达171.94 mm;1月份多年平均降水量最低,仅为5.95 mm;7月份降水量多年呈降低趋势,且减幅最大;春季和冬季降水量呈增加趋势,夏季和秋季降水量呈下降趋势,4个季节降水量趋势均不显著;近30年沈阳市年降水量总体上呈现出不明显的下降趋势,平均降水量为663.12 mm;②年降水量在1998和2002年发生突变,春季降水量在2004年发生突变,夏季降水量在1996和1998年发生突变,但变化趋势均不显著。分析结果对进一步开展沈阳市降水评估以及防洪工作有重要意义。

Based on the daily precipitation data of Shenyang from 1991 to 2020,using the linear regression method and the percentage method,the variation characteristics of annual,seasonal and monthly precipitation in Shenyang city are analyzed,and the Mann-Kendall method is used to analyze the sudden change of annual and four seasons precipitation.The results show that①Shenyang has the highest annual average precipitation in August,171.94 mm,the lowest annual average precipitation in January,5.95 mm only in July,precipitation declined over many years,and the maximum reduction;Spring and Winter precipitation is increasing,the precipitation in Summer and Autumn is decreasing,four seasons precipitation trend is not significant;in the past 30 years,the annual precipitation in Shenyang has shown an insignificant decreasing trend,average precipitation mm.663.12.②The annual precipitation mutated in 1998 and 2002,Spring precipitation mutated in 2004,Summer precipitation mutated in 1996 and 1998,but the trend of change is not significant.The analysis results are of great significance to further evaluation of precipitation and flood control in Shenyang.