吉林省近60年降水量时空演化特征分析

Temporal and Spatial Features Analysis of Precipitation in Recent 60Years in Jilin Province

为准确分析吉林省1951~2011年近60年年降水量时空演化特征,基于8个雨量站年降水量数据,采用一元线性回归分析法、预置白Mann-Kendall法(PW-MK法)进行趋势特征分析,结合预置白Mann-Kendall法和滑动t检验法进行突变特征检测,并采用Morlet小波进行周期特征识别。结果表明,1951~2011年吉林省各站年降水量均呈减少趋势,年降水量多年平均值在三大地貌单元上自西向东呈增加趋势,其与雨量站高程存在较强的正相关关系,且年降水量自东向西减少趋势越来越显著,其中西部和中部呈显著性减少趋势,东部呈不显著减少趋势;吉林省西部和中部降水突变年份在1998年前后,东部突变年份在1975年前后;吉林省各站均存在5、10年左右的主周期,其中,西部和中部还存在15、20年左右的主周期,东部还存在15、28年左右的主周期。

In order to accurately analyze the temporal and spatial evolution characteristics of annual precipitation over the past 60 years in Jilin Province from 1951 to 2011,linear regression analysis and PW-MK method were used to analyze the trend characteristics based on the annual rainfall data of 8 rainfall stations.Combination of the PW-MK method and sliding t-test was used for sudden change detection.Morlet wavelet method was used to periodic feature recognition.The results show that the trend features are as follows.The annual precipitation decreased from 1951 to 2011 in all stations of Jilin Province.On the spatial distribution,the annual average of annual precipitation showed an increasing trend from west to east over the three major geomorphological units.There is strong positive correlation between the rainfall station elevation and the annual precipitation.The annual precipitation has a decrease trend from east to west,which is significant trend in the west and middle part,and is insignificant decrease trend in the east part.Mutational characteristics are as follows.The year of mutation was around 1998 in the western and central Jilin Province and the year of the eastern mutation was around 1975.There are 5 or 10 years of major cycles in all stations in Jilin Province.There are still 15 and 20 years of major cycles in the west and center,and 15 and 28 years cycles in the eastern part of Jilin Province.