Adjustment of the Evaporation Pan Coefficient: Case Study of Konya Closed Basin

Abstract

AbstractGlobal warming is an accepted fact by everyone, even if climate change still seems to be a controversial issue. The increase in temperature caused by global warming increases the rate of evaporation from open water surfaces. Although it is necessary that the presence of water and removing the saturated vapour layer from the air with the wind to keep on evaporation, temperature is an essential factor. Evaporation is the most difficult component of the hydrological cycle to determine. Evaporation can be estimated by various methods. One of them is the evaporation pan even if the value measured cannot be expected to represent evaporation in large bodies of water. The pan is more easily affected by changes in temperature in the air. Another is the empirical evaporation estimation methods based on measured meteorological parameters. One of these methods is Penman. The Penman method is used as a reference method in studies related to evaporation since it gives the closest results to the measured data in different parts of the world. In this study, evaporation rate was estimated by the Penman method using data measured at five meteorological stations in the Konya Closed Basin. The aim of the study is to recalculate the pan coefficient, which is used as 0.7 in Turkey. The Artificial bee colony algorithm, one of the statistical optimization techniques, was used for this purpose. It was concluded that the measurements would close to Penman estimates if the pan coefficient was taken as 0.79 for the Konya Closed Basin.KeywordsEvaporationPenmanPan coefficientKonya Closed Basin