Proceedings of the 2023 Mississippi Water Resources Conference

Year: 2023 Authors: Yang Y., Anderson M., Hain C.

The Lower Mississippi Alluvial Plain (LMAP) is one of the most productive regions in the United States, with large area of corn, soybean, rice and cotton planted. Associated with the intensified agricultural activities, this region has been experiencing a rapid decrease of ground water table that can threaten the sustainability of water supply and this condition may get worse under the changing climate. To solve the issue with groundwater depletion, it is critical to understand how the irrigation water is currently used by various crop types and different fields. Evapotranspiration (ET) represents the land surface water use and is a key parameter in the hydrological cycle. Field-scale ET retrieved from satellite data has been heavily evaluated by comparing with flux tower observations and proved to be efficient for agriculture management impact study, crop water use accounting, crop yield estimation, and irrigation scheduling. This work will assess ET in the LMAP region at field scale to provide critical local water use information for improved agriculture and water resource management. The energy balance model based on remotely sensed data will be used to estimate field-scale daily ET with key inputs from Landsat 8 and Landsat 9 from NASA. Through the OpenET project, with six widely used ET models implemented into Google Earth Engine to leverage the strong cloud computational power, field-scale large area ET over the LMAP region will be estimated. This work will help to address the challenge of water resource sustainability under the changing climate over the environmental vulnerable area.