无锡市近50年降水变化特征分析

Analysis of Precipitation Variation Characteristics in Wuxi City over the Past 50 Years

气候在水文循环过程中是一个重要的因素,降水作为气候要素中最直接、最敏感的要素,其变化情况对人类生产生活产生最直接的影响。本文以大运河(无锡)水文站为代表,采用滑动平均、回归分析、Mann-Kendall检验以及小波分析方法对无锡市1971—2020年共50年降水量进行分析。分析结果表明:无锡市降水量年内分布呈单峰型,降水量最大的月份为6月,最大的季节为夏季。降水量年际变化呈显著上升趋势,平均上升速度为58.68mm/10a。降水量存在18~20年、11~12年以及4~5年这三种时间尺度下的循环周期,最为显著的主周期为12年。

Climate is a crucial factor in the hydrological cycle,and precipitation,as the most direct and sensitive element of climate,has a direct impact on human production and livelihood.This paper takes the Grand Canal(Wuxi)Hydrological Station as a representative,and employs methods such as moving average,regression analysis,Mann-Kendall test,and wavelet analysis to analyze the precipitation data in Wuxi City from 1971 to 2020,covering a period of 50 years.The analysis results reveal that the annual distribution of precipitation in Wuxi City follows a unimodal pattern,with the highest rainfall occurring in June and the peak season being summer.There is a significant increasing trend in annual precipitation,with an average growth rate of 58.68 mm per decade.The precipitation data exhibits cyclic patterns at three time scales:18~20 years,11~12 years,and 4~5 years,with the most prominent main cycle being 12 years.