Spatial and Temporal Changes in Grass-­Reference Evapotranspiration (EC3022)

Changes in reference (potential) evapotranspiration as a function of change in climate variables can substantially impact availability and utilization of water resources, which can lead to changes in agricultural operations and productivity. This Extension Circular includes scientific findings, visual interpretation, and discussion of geographic (spatial) variation and patterns of historical reference evapotranspiration across the 834 counties in the United States Great Plains. It also includes the temporal (1968–­2013) trends observed in reference evapotranspiration for each county, and potential consequences and significance of these trends in the context of agricultural production and water resources in the region.