基于Morlet小波的长沙寒露风周期分析

Analysis of Cold Dew Wind Period in Changsha Based on Morlet Wavelet

摘要: 本文利用Excel、Matlab、Surfer等软件，采用Morlet复小波对1959~2023年长沙寒露风指数时间序列进行小波分析，分析了长沙寒露风振荡和周期变化规律。结果表明，长沙寒露风存在4年、20年、12年3类尺度的周期变化。其中第二主周期20年在20世纪80年代振荡开始加强，90年代后振幅越来越剧烈，说明气候变暖，长沙寒露风侵袭不但没有变弱，而且越来越强，为中度–重度寒露风和极轻度和无寒露风交替出现态势，研究成果为长沙农业生产防灾减灾提供理论依据。

Abstract: This article uses software such as Excel, Matlab, and Surfer to perform wavelet analysis on the time series of the Changsha Cold Dew Wind Index from 1959 to 2023 using Morlet complex wavelets, and analyzes the oscillation and periodic changes of the Changsha Cold Dew Wind. The results indicate that the cold dew wind in Changsha exhibits periodic variations on three scales: 4 years, 20 years, and 12 years. The oscillation of the second main cycle began to strengthen in the 1980s, and the amplitude became increasingly severe after the 1990s, indicating that due to climate warming, the invasion of cold dew winds in Changsha not only did not weaken, but also became stronger. This provides a theoretical basis for the alternating occurrence of moderate to severe cold dew winds and extremely mild and no cold dew winds in Changsha’s agricultural production.