Implementation of Automated METRIC Algorithms on the NASA Earth Exchange for Rapid Consumptive Water Use and Drought Impact Mapping in California’s Central Valley

Abstract:

Consumptive water use mapping from agricultural areas in California’s Central Valley is critical for understanding historical surface and groundwater use. During times of drought, groundwater is commonly pumped to supplement reduced surface water supplies in the Central Valley. Due to the lack of extensive groundwater pumping records, mapping consumptive use using satellite imagery is an efficient and robust way for estimating agricultural water use and assessing drought impacts. The objective of this work was to partner with NASA Ames researchers and further develop and implement automated calibration algorithms for estimating evapotranspiration using the METRIC remotely sensed surface energy balance model. Specifically, this study utilizes the NASA Earth Exchange (NEX) computing facilities along with automated calibration algorithms for METRIC to rapidly process Landsat satellite imagery and estimate field scale evapotranspiration and drought impacts for the Central Valley. This research sets the stage for larger consumptive use and drought monitoring at the field scale over the western U.S.