Water Use Estimation using SSEBop ET model and remote sensing radiation data in the United States

Evapotranspiration (ET) is a vital component of the water cycle and remote sensing provides an effective method to mapping water use and availability. We used the Operational Simplified Surface Energy Balance (SSEBop) model to estimate water use in the United States using actual ET numbers. One of the main driver in the model is the temperature difference (dT) parameter, which is the difference between dry bare surface and canopy surface temperature to determine the proper boundary conditions for the available energy transfer during the evapotranspiration process. Instead of using meteorological data, we used remote sensing data to determine dT. This allows for a more consistent data input, improved the ET output data and with that advances the ability to estimate water use on a large scale. Results are evaluated using eddy covariance flux tower data. Remote sensing-based water use mapping is important tool for sustainable agricultural production helping stakeholders and water managers to gain understanding of the impact to land use changes due to the ever-changing water consumption and availability.