A review on evapotranspiration data assimilation based on hydrological models  

基于水文模型的蒸散发数据同化研究进展（英文）

作　　者：董晴晴 占车生 王会肖 王飞宇 朱明承 

机构地区：[1]College of Water Sciences,Beijing Normal University [2]Key Laboratory of Water Cycle and Related Land Surface Processes,Institute of Geographic Sciences and Natural Resources Research,CAS [3]University of Chinese Academy of Sciences

出　　处：《Journal of Geographical Sciences》2016年第2期230-242,共13页地理学报（英文版）

基　　金：National Key Basic Research Program of China(973 Program),No.2015CB452701;National Natural Science Foundation of China,No.41271003;No.41371043;No.41401042

摘　　要：Accurate estimation of evapotranspiration(ET),especially at the regional scale,is an extensively investigated topic in the field of water science. The ability to obtain a continuous time series of highly precise ET values is necessary for improving our knowledge of fundamental hydrological processes and for addressing various problems regarding the use of water. This objective can be achieved by means of ET data assimilation based on hydrological modeling. In this paper,a comprehensive review of ET data assimilation based on hydrological modeling is provided. The difficulties and bottlenecks of using ET,being a non-state variable,to construct data assimilation relationships are elaborated upon,with a discussion and analysis of the feasibility of assimilating ET into various hydrological models. Based on this,a new easy-to-operate ET assimilation scheme that includes a water circulation physical mechanism is proposed. The scheme was developed with an improved data assimilation system that uses a distributed time-variant gain model(DTVGM),and the ET-soil humidity nonlinear time response relationship of this model. Moreover,the ET mechanism in the DTVGM was improved to perfect the ET data assimilation system. The new scheme may provide the best spatial and temporal characteristics for hydrological states,and may be referenced for accurate estimation of regional evapotranspiration.Accurate estimation of evapotranspiration （ET）, especially at the regional scale, is an extensively investigated topic in the field of water science. The ability to obtain a con- tinuous time series of highly precise ET values is necessary for improving our knowledge of fundamental hydrological processes and for addressing various problems regarding the use of water. This objective can be achieved by means of ET data assimilation based on hydro- logical modeling. In this paper, a comprehensive review of ET data assimilation based on hydrological modeling is provided. The difficulties and bottlenecks of using ET, being a non-state variable, to construct data assimilation relationships are elaborated upon, with a discussion and analysis of the feasibility of assimilating ET into various hydrological models. Based on this, a new easy-to-operate ET assimilation scheme that includes a water circula- tion physical mechanism is proposed. The scheme was developed with an improved data assimilation system that uses a distributed time-variant gain model （DTVGM）, and the ET-soil humidity nonlinear time response relationship of this model. Moreover, the ET mechanism in the DTVGM was improved to perfect the ET data assimilation system. The new scheme may provide the best spatial and temporal characteristics for hydrological states, and may be ref- erenced for accurate estimation of regional evapotranspiration.

关 键 词：EVAPOTRANSPIRATION data assimilation hydrological model non-state variable 

分 类 号：P426.2[天文地球—大气科学及气象学]