1960—2020年珠江流域跨季节尺度干旱时空变化  

Spatiotemporal variations of cross-seasonal drought in the Pearl River Basin of China from 1960 to 2020

作　　者：张灵[1] 吴恩捷 潘浩桦 张朱琳 何钰珍 ZHANG Ling;WU Enjie;PAN Haohua;ZHANG Zhulin;HE Yuzhen(School of Geography and Remote Sensing,Guangzhou University,Guangzhou 510006,China)

机构地区：[1]广州大学地理科学与遥感学院,广州510006

出　　处：《农业工程学报》2024年第13期77-84,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金面上项目(42071123)。

摘　　要：全球气候变化背景下,珠江流域干旱事件尤其是跨季节干旱事件频发,研究珠江流域不同时间尺度下的干旱时空特征对于流域水资源配置和农业结构调整至关重要。为了了解珠江流域跨季节干旱时间时空变化特征,研究基于1960—2020年珠江流域44个气象站逐日气象观测数据,计算不同时间尺度下的标准化降水蒸散指数(standardized precipitation evapotranspiration index,SPEI),结合线性倾向估计法、Mann-Kendall突变检验以及Morlet小波分析,分析了近60 a来珠江流域跨季节干旱时空变化特征。结果表明:1)1960—2020年间珠江流域跨季节干旱事件中,秋冬及秋冬春连旱化趋势显著,呈弱干旱化趋势,且干旱化频率有所上升,连旱强度以中旱和轻旱为主,连旱影响范围以局域性为主,其次为全域性,秋冬春季节连旱在1962年和1997年分布出现由干转湿和由湿转干的突变。2)珠江流域秋冬及秋冬春季节连旱普遍存在9~14 a变化周期,相关分析表明珠江流域干湿变化与同期厄尔尼诺现象显著相关。3)珠江流域秋冬及秋冬春季节连旱尺度下大致呈东西干而中间湿的空间分布格局,红水河至左江及郁江流域连旱化趋势减弱,但连旱化频率仍较高,东江流域秋冬季节连旱化频率高且呈弱连旱化趋势,湿润化速率自西南向东北递减,未来发生季节连旱风险高。研究结果可为珠江流域干旱监测与防灾减灾措施提供指导和建议。The Pearl River Basin is one of the most important agricultural areas and water sources in the subtropical humid region of southern China.Drought events occur frequently in the Pearl River Basin under the background of global climate,especially for the continuous seasonal drought.The temporal and spatial evolution of drought at different time scales is of great significance to allocate the water resources for the agricultural planting structure in the Pearl River Basin.In this study,the daily observation data was selected from 44 meteorological stations in the Pearl River Basin from 1960 to 2020.The precipitation and potential evapotranspiration(ET0)was then calculated by the FAO Penman-Monteith,in order to obtain the standardized precipitation evapotranspiration index(SPEI)at the cross-seasonal drought time scale.Linear tendency estimation was combined with Mann-Kendall mutation test and Morlet wavelet analysis.The temporal and spatial variation of continuous seasonal drought was then analyzed over the past 60 years.The result showed that:1)The instable precipitation was led to the complex and diverse dry and wet changes.The growth trend of the continuous drought was found in autumn-winter and autumn-winter-spring.This variation was attributed to the decrease of autumn precipitation and the concentration of winter precipitation.The frequency of drought was also higher than that before the 21st century.Specifically,the frequency of continuous drought in autumn-winter-spring increased from 0.15 times/a before 2000 to 0.25 times/a after 2000.And there were many consecutive seasonal drought events from 2000 to 2010.The intensity of drought was mostly light and moderate and the continuous drought coverage area is mainly characterized by local,followed by regional drought.Particularly,the drought from dry to wet and from wet to dry occurred in the continuous drought of autumn-winter-spring in 1962 and 1997,respectively.2)There were the outstanding interannual and interdecadal variations of SPEI in the continuous droug

关 键 词：干旱 珠江流域 SPEI 时空特征 M-K突变检验 MORLET小波分析 

分 类 号：P429[天文地球—大气科学及气象学]