Potential Evapotranspiration

This layer offers a 1km cell-sized raster displaying the average annual evaporative loss from the land surface, measured in millimeters per year. The data is sourced from the MOD16 Global Evapotranspiration Product, created by a team of researchers at the University of Montana, utilizing MODIS imagery. The algorithm estimates land surface temperature and albedo, then applies the Penman-Monteith equation to derive evapotranspiration values. However, it's important to note that this algorithm does not apply to urban or barren land designated as No Data, along with open water areas. For all other pixels, evapotranspiration was estimated for each 8-day period from 2000 to 2014, and these estimates were subsequently averaged to determine the annual normal.

We selected for areas that have 50 inches or less of average annual evaporative loss.

Source information: MODIS Global Evapotranspiration Projec (MOD16)