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。

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 set-based flux obser vation products ET_jung, and energy balance-based diagnosis models ET_modis, ET_PML, and ET_Zhangke, were compared in the Hanjiang River Basin. The results showed that the model tree set-based flux observation product and energy balance-based 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 South-to-North Water Transfer Project.

国家自然科学基金项目( 41330529; 41571024)