基于SPEI的海河流域干旱时空演变特征及环流成因分析  

Analysis of spatial and temporal evolution characteristics and circulation causes of drought in Haihe River Basin based on SPEI

作　　者：王卫光 黄茵[1,2] 邢万秋 魏佳[1,2] WANG Weiguang;HUANG Yin;XING Wanqiu;WEI Jia(State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China;College of Hydrology and Water Resources,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [2]河海大学水文水资源学院,江苏南京210098

出　　处：《水资源保护》2020年第3期8-13,共6页Water Resources Protection

基　　金：国家自然科学基金(51779073);江苏省杰出青年基金(BK20180021)。

摘　　要：基于海河流域31个气象站1961—2017年逐日气象资料、美国国家环境预报中心(NCEP)和美国国家大气研究中心(NCAR)再分析数据集,计算了多时间尺度标准化降水蒸散指数(SPEI),分析了海河流域1961—2017年干旱时空演变特征,并结合流域夏季500 hPa等位势高度场分析了流域干旱演变特征的环流成因。结果表明:1961—2017年海河流域有轻微干旱趋势,且长历时干旱主要集中于1980—2017年,但干旱强度呈减弱趋势,春末(5、6月)湿润化趋势显著,夏季(7、8月)干旱化趋势显著;空间分布上,海河流域内57.4%的区域呈现干旱化趋势,19.0%的区域呈现干旱减弱趋势,全流域夏季呈显著干旱化趋势;蒙古高压增强、西太平洋副热带高压西移、南扩以及增强的环流特征不利于水汽输送及降水形成,高压系统的增强和水汽输送的减少是流域夏季干旱化趋势的原因之一。Based on the daily meteorological data of 31 meteorological stations in Haihe River Basin from 1961 to 2017 and reanalysis data set of NCEP and NCAR,the multi time scale standardized precipitation evapotranspiration index(SPEI)is calculated,and the temporal and spatial evolution characteristics of drought in Haihe River Basin from 1961 to 2017 are analyzed.Combined with the 500 hPa geopotential height field in summer,the circulation causes of the characteristics of the basin drought evolution are analyzed.The results show that there is a slight drought trend in the Haihe River Basin from 1961 to 2017,and the long-term drought is mainly concentrated in 1980—2017,but the drought intensity is weakening,and there is a significant wetting trend at the end of spring(May and June),and a significant drought trend in summer(July and August).In terms of spatial distribution,57.4%of the area in Haihe River Basin shows a drought tendency,19.0%of the area shows a trend of drought weakening,and the whole basin shows a significant drought tendency in summer.The intensified of the Mongolian high,the westward movement and southward expansion of the Western Pacific subtropical high and the enhanced circulation characteristics are not conducive to water vapor transport and precipitation formation.The enhancement of high pressure system and the decrease of water vapor transport are the main reasons for the trend of summer drought trend in the basin.

关 键 词：标准化降水蒸散指数 干旱 大气环流 海河流域 

分 类 号：TV125[水利工程—水文学及水资源] P333[天文地球—水文科学]