WATER INTERNATIONAL, cilt.23, sa.3, ss.184-189, 1998 (SCI-Expanded)
Pan evaporation measurements are widely used to estimate evapotranspiration and free water evaporation. Pan evaporation measurements are critical to many applications including irrigation system design, irrigation scheduling, and hydrologic modeling. In many locations, reliable climate measurements consist of daily minimum screen temperature, daily maximum, rainfall, and windspeed. In many situations, it is advantageous to calculate rather than measure pan evaporation. Many formulas have been developed which predict pan evaporation as a function of limited meteorological observations. One of them, a simplified version of Penman's evaporation formula, requires only temperature, wind and dewpoint data in addition to latitude and elevation. This paper evaluates the Penpan Equation for the case of a pan and tests its universality. Estimates differ from measured values by about 0.65 mm/day, at 19 locations in Turkey.