王松 田巍 刘小莽 刘昌明

摘要：蒸散发是流域水循环和能量循环的重要环节，准确估算蒸散发对流域水循环研究具有重要意义，同时也可以为流域水资源优化配置和可持续利用提供支撑。利用汉江流域观测的逐月降水数据、径流数据以及重力卫星（GRACE）反演的流域蓄水量变化数据计算水量平衡蒸散发（ET_WB），以ET_WB为标准在月尺度上评估4类9种不同蒸散发产品（陆面模式产品ET_clm、ET_noah、ET_mos、ET_vic；再分析数据产品 ET_jra；基于模型树集的通量观测产品ET_jung和基于能量平衡的诊断模型产品ET_modis、ET_PML、ET_Zhangke）在汉江流域的适用性。结果表明基于模型树集的通量观测产品和基于能量平衡的诊断模型产品精度较好，再分析产品次之，陆面模式产品（除ET_clm）较差。ET_jung、ET_modis和ET_clm在月尺度上与ET_WB有着较好的相关性，结果误差相对较小；ET_noah、ET_mos、ET_vic结果误差相对较大。该研究结果可以为汉江流域水循环研究和南水北调中线工程管理提供科学参考。

关键词：实际蒸散发；蒸散发产品；流域蓄水变化；GRACE；汉江

中图分类号：P333文献标志码：A文章编号：16721683（2018）03000109

Comparisons of various evapotranspiration products in the Hanjiang River Basin

WANG Song1，2，TIAN Wei1，2，LIU Xiaomang1，LIU Changming1

（1.Key Laboratory of Water Cycle & Related Land Surface Process，Institute of Geographic

Sciences and Natural Resources Research，Chinese Academy of Sciences， Beijing 100101，China；

2.University of Chinese Academy of Sciences，Beijing 100049，China）

Abstract：Evapotranspiration （ET） plays a critical role in linking the water and energy cycle.Accurately estimating ET is important for hydrologic study and supports the optimal allocation and sustainable use of water resources.In this study， monthly precipitation data，runoff data， and GRACE terrestrial water storage data were used to estimate ET with the water balance approach （ET_WB） as the reference.9 ET products，including land surface model products ET_clm，ET_noah，ET_mos and ET_vic，reanalysis product ET_jra，model tree setbased flux observation products ET_jung，and energy balancebased diagnosis models ET_modis， ET_PML，and ET_Zhangke，were compared in the Hanjiang River Basin.The results showed that the model tree setbased flux observation product and energy balancebased diagnosis model products had better accuracy，followed by the reanalysis product and the land surface model products.ET_jung，ET_modis，and ET_clm had a good correlation with ET_WB on the monthly scale. ET_noah， ET_mos，and ET_vic had large error among the 9 products.This study can provide a scientific reference for the hydrologic study of the Han River and the management of the Middle Route of the SouthtoNorth Water Transfer Project.

Key words：actual evapotranspiration；evapotranspiration products；terrestrial water storage；GRACE；the Hanjiang River Basin

流域蒸散发是流域内土壤蒸散发、植被蒸腾、水面蒸散发、截留蒸散发等的总和，是流域水循环的基本环节和水量平衡的基本要素[1]。從全球陆面平均来看，约58%～65%的降水通过蒸散发重返大气，消耗的能量约占净辐射的51%～58%[2]，因此蒸散发一定程度上决定了区域甚至全球的水量平衡过程，同时也影响着区域的水文-生态-大气这个复杂系统的演变[3]。准确观测和估算流域蒸散发对全球气候变化和区域水资源综合利用具有重要意义，同时也对农作物需水管理、旱情监测等具有重要价值。……