Global Actual Evapotranspiration at Daily/1-km Resolution from 2000 to 2019

Terrestrial actual evapotranspiration (ET) is an essential ecohydrological process linking the land surface energy, water and carbon cycles, and plays a critical role in the earth system. This global ET dataset is obtained based on ETMonitor model, which combines parameterizations for different processes and land cover types, with multi-source satellite data as input. Several open accessed remote sensing variables, e.g., LAI, FVC, albedo, surface soil moisture, dynamic surface water cover and snow/ice cover, were used as input to estimate daily ET. The meteorological variables from ERA5 reanalysis dataset were also adopted. The ETMonitor model is applied at daily scale to estimate the ET components at 1-km resolution, including vegetation transpiration, soil evaporation, canopy precipitation interception loss, water surface evaporation and snow/ice sublimation on daily step, and the total actual ET is estimated as the sum of these components. Overall, the actual ET estimated by ETMonitor agreed well with ground measurements from 251 flux towers across various ecosystems and climate zones globally, with high correlation (0.75), low bias (0.08mm/d), and low root mean square error (0.93 mm/d). The estimated ET showed reasonable spatial patterns, and superior in presenting the spatial variation of ET especially in the mountain regions and in the arid irrigated cropland regions. The ETMonitor global actual evapotranspiration dataset released now covers the whole world with 1-km spatial resolution and daily time step, and the unit is mm/d. The data type is 16-bit signed integer, the scale factor is 0.01, The missing values were filled by -1. Users are required to cite the following reference: Zheng C., Jia L., Hu G. Global Land Surface Evapotranspiration Monitoring by ETMonitor Model Driven by Multi-source Satellite Earth Observations. Journal of Hydrology, 2022, 128444; https://doi.org/10.1016/j.jhydrol.2022.128444. Zheng C., Jia L., Hu G. 2022. Global Land Surface Evapotranspiration Monitoring by ETMonitor Model Driven by Multi-source Satellite Earth Observations. Journal of Hydrology. https://doi.org/10.1016/j.jhydrol.2022.128444.