基于Morlet小波的呼伦湖流域降水多时间尺度分析

Analysis on Multi Time Scale Yearly Precipitation of Hulun Lake Watershed Based on Wavelet Morlet Analysis

利用Morlet小波分析方法对呼伦湖流域,海拉尔市、满洲里市、克鲁伦河水文站与乌尔逊河水文站的1961—2014年降水序列进行小波特征分析,根据降水序列多时间尺度分析结果,揭示呼伦湖流域多年降水变化特征。结果表明:(1)研究区年降水量的周期变化特征主要为,海拉尔市年平均降水存在6a,11a与27a的主周期;满洲里市存在10a,16a与27a的主周期;克鲁伦河存在7a,13a与28a的主周期;乌尔逊河存在5a,13a,20a与29a的主周期。(2)通过对各序列枯水期的计算,预测海拉尔市与满洲里市将于2017年进入枯水期,克鲁伦河与乌尔逊河将于2019年进入枯水期;(3)预测显示呼伦湖流域在2018—2026年,呼伦湖流域降水减少,进入枯水期;在2027—2035年,呼伦湖流域的降水量充沛,进入丰水期。

The Morlet wavelet method is used to analyze the precipitation data series from 1961 to 2014 at Hailaer,Manzhouli,Kelulun river gauge stations and Wuerxun River gauge station of Hulun Lake watershed.The characteristics of the annual precipitation variation of Hulun Lake watershed are determined by the multiple time scale analysis of the precipitation time series.(1)The main periodic variations of the annual precipitation of the research basin are as follows.There are 6-year,11-year and 27-year main variation periods of average annual precipitation in Hailaer city;there are 7-year,13-year and 28-year main variation periods of average annual precipitation at Kelulun river gauge station,and there are 5-year,13-year and 29-year main variation periods of average annual precipitation at Wuerxun river gauge station.(2)Based on estimation of the dry periods of each station,it is predicted that Hailaer and Manzhouli will be in the dry periods since 2017,and Kelulun river and Wuerxun river will be in the dry periods since 2019.(3)It is predicted that Hulun Lake will be in the dry period in 2018-2026,and it will be in the wet season in the period from 2027 to 2035.