多源蒸散发数据融合及其在干旱监测中的应用  

Fusion of multi-source evapotranspiration data and its application in drought monitoring

作　　者：王文 杨佳汇[3] 花甜甜 彭珉 WANG Wen;YANG Jiahui;HUA Tiantian;PENG Min(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;Dayu College,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 [3]河海大学大禹学院,江苏南京210098

出　　处：《人民长江》2020年第8期19-26,共8页Yangtze River

基　　金：国家重点研发计划课题项目(2017YFC0406101);国家自然科学基金项目(41961134003)。

摘　　要：目前,蒸散发和干旱相关的研究不全面,对蒸散发在干旱形成发展过程中的作用机理不明确,对蒸散发在干旱监测中的价值没有客观的认识。为此,利用地面通量观测数据对3种蒸散发数据(GLEAM,GLDAS,SSEBop)进行了精度评估,在此基础上进行数据融合,进而根据4种干旱指数(SPI,RDI,ESI,SMI)分析了我国近年来干湿变化特征及各指数在典型干旱事件监测中的特点。结果表明:①与单一数据产品相比,融合数据减小了与实测数据间的偏差,提高了可靠性;②2001~2015年,东北平原西北部、内蒙古北部、华北平原、云贵高原、青藏高原大部分地区以及塔里木盆地中部有显著变干趋势,而西北及东北地区的主要山脉沿线地区呈现变湿趋势;③1个月尺度的SPI、RDI指数能较好地反映干旱事件的开始与结束,但对干旱持续性表征较差,ESI和SMI的变化滞后于SPI与RDI,能较好地反映干旱程度和持续性。At present,the research on evapotranspiration and drought is not comprehensive,the mechanism of evapotranspiration in the process of drought formation and development is not clear,and there is no objective understanding on the significance of evapotranspiration in drought monitoring.GLEAM,GLDAS and SSEBop evapotranspiration data are evaluated and merged based on their accuracy.Four drought indices(SPI,RDI,ESI,SMI)were used to analyze aridity changes over China in recent years.The results showed that:①Merged ET data had better accuracy than each individual product;②From 2001 to 2015,the northwestern plain of Northeast China,the northern part of Inner Mongolia,the North China Plain,the Yunnan-Guizhou Plateau,most of the Qinghai-Tibet Plateau,and the center of Tarim Basin showed a significant drying trend whereas major mountains in northeastern and northwester China show a trend of wet;③1-motnth scale SPI and RDI indices could better reflect the beginning and end of a drought,but poorly reflect the persistence of the drought;ESI and SMI change lag behand SPI and RDI,and they can better indicate the severity and persistence of drought.

关 键 词：蒸散发 GLEAM GLDAS SSEBop 数据融合 干湿变化 干旱监测 水文气象学 

分 类 号：P332[天文地球—水文科学]