东北暖季冷涡降水日变化的聚类分析  

Clustering Analyses of Diurnal Precipitation Variations Associated with the Northeast Cold Vortex in Warm Season

作　　者：朱晓彤 姚凯 涂钢[1,2] 杨旭 吴彤[4] ZHU Xiaotong;YAO Kai;TU Gang;YANG Xu;WU Tong(Jilin Meteorological Sciences Institute,Changchun 130062;Jilin Province Key Laboratory of Changbai Mountain Meteorology and Climate Change,Changchun 130062;Jilin Meteorological Observatory,Changchun 130062;Yingkou Meteorological Observatory,Yingkou,Liaoning Province 115001)

机构地区：[1]吉林省气象科学研究所,长春130062 [2]长白山气象与气候变化吉林省重点实验室,长春130062 [3]吉林省气象台,长春130062 [4]营口市气象台,辽宁营口115001

出　　处：《气候与环境研究》2024年第2期136-144,共9页Climatic and Environmental Research

基　　金：国家重点研发计划2023YFC3007702;国家自然基金面上项目42275015;中国气象局创新发展专项CXFZ2023P004、CXFZ2022P005、CXFZ2022J007;吉林省气象局技术发展专项202314、202101。

摘　　要：使用2017~2022年5~9月逐小时三源融合实况格点降水(CMPAS)资料,采用K-均值聚类算法对东北暖季冷涡降水日变化分类,分析其特征及空间分布,结果显示:1)东北暖季冷涡降水多年平均降水量空间分布从西北到东南增加,降水频次的空间分布与其相似,降水强度大值区集中在辽东半岛附近。2)东北地区冷涡背景下降水量、降水频次和降水强度暖季平均日变化均呈双峰型,降水量的下午主峰值主要源于降水频次,而夜间次峰值与降水频次和降水强度均关系密切。3)聚类后冷涡降水量、降水频次的日变化表现为单峰型和双峰型特征,且单峰型格点占比较大,降水强度的日变化表现为单峰型。依据峰值出现时间及日变化形态间差异,降水量、频次与强度均可划分为4类不同的日变化类型。4)各类日变化空间占比统计结果显示,冷涡降水量、降水频次日变化存在下午峰值的格点均占比最大,夜间峰值次之,两者聚类后区域特征明显,与地形关系密切且分布相对规整;冷涡降水强度日变化下午单峰型格点占比最大,聚类后空间分布较为零散。Using the China Meteorological Administration(CMA)Multisource Precipitation Analysis System and European Center’s Fifth Generation Reanalysis data for warm seasons(May–September)from 2017 to 2022,precipitation Mar.2024 Climatic and Environmental Research characteristics and diurnal variation patterns are classified using the K-means clustering algorithm under the background of cold vortex in the Northeast China.The following conclusions are drawn from the study.1)The spatial distribution of the multiyear average precipitation amount shows an increasing trend from the northwest toward the southeast.A similar pattern is observed in the spatial distribution of precipitation frequency,and high-intensity precipitation areas are concentrated near the Liaodong Peninsula.2)Under the influence of cold vortex,average diurnal variations in precipitation amount,frequency,and intensity exhibit a bimodal pattern.The main diurnal peak in the precipitation amount is primarily attributed to precipitation frequency,while the secondary peak exhibits a remarkable correlation with precipitation frequency and intensity.3)Third,diurnal variations in the precipitation amount and frequency exhibit either unimodal or bimodal characteristics,while precipitation intensity shows a unimodal distribution.Based on the peak time and patterns,the precipitation amount,frequency,and intensity can be classified into four distinct types of diurnal variation.4)The spatial distribution statistical results show that grid points exhibiting afternoon peaks form the largest proportion of daily variations in precipitation amount,frequency,and intensity.This is followed by nocturnal peaks.Meanwhile,two variation types display evident regional features closely tied to topography and a relatively orderly distribution.Concerning diurnal variations in cold vortex precipitation intensity,grid points with a single afternoon peak dominate,with their spatial distribution becoming more dispersed after applying the clustering algorithm.

关 键 词：东北冷涡 降水日变化 K-均值聚类算法 暖季 空间分布 

分 类 号：P426.62[天文地球—大气科学及气象学]