Trends in pan evaporation and actual evapotranspiration across the conterminous US:: Paradoxical or complementary? -: art. no. L13503

Pan evaporation (ETpan) has decreased at 64% of pans in the conterminous U.S. over the past half-century. Comparing trends in ETpan and water budget-derived actual evapotranspiration (ETa*), we observe the so-called "Pan Evaporation Paradox,'' which we confirm is no more than a manifestation of the complementarity between actual evapotranspiration (ETa) and potential evapotranspiration (ETp). Examining trends in the components of ETa - the radiative energy and regional advective budgets - we show that both components must be considered together to explain the relationship between ETpan and ETa*.