sezer, çağlar özkan ankara üniversitesi - ziraat fakültesi - tarımsal yapılar ve sulama bölümü, Ankara, Turkey , öztekin, tekin gaziosmanpaşa üniversitesi - ziraat fakültesi - biyosistem mühendisliği bölümü, Tokat, Turkey , kutlu sezer3, esra ankara üniversitesi - ziraat fakültesi - toprak bilimi ve bitki besleme bölümü, Ankara, Turkey

Prediction of Class-A Pan Evaporation By Using Penman and Priestley-Taylor (PT) Models

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Objective: This study researched for two years; how evaporation models with daily climate data will predict when weather station is new installed somewhere that does not have a weather station previously, when there is no meteorological data for many years or when daily immediately evaporation data are needed. Material and Methods: Two models chosen as Penman (1948) and Priestley-Taylor (PT) (1972), which give the amount of evaporation, were used for this study. These models estimated the amount of evaporation from the A class evaporation pan (Epan) were tried under the humid climate conditions of Samsun in years 2012 and 2013. In terms of climatic characteristics, 2012 and 2013 were different from long time periods annual averages and extremely rainy. Statistical methods given as regression test (R2), root mean square error (RMSE), average deviation (AD), average relative percentage error (ARPE), coefficient of efficiency (CE) were used to find out the success of Epan values measured in the station and predicted by models. The performance of Epan values of the models were evaluated daily and monthly (by using daily totals). Epan in the weather station installed for six months (from April – to October). During this time, total Epan values measured in the station and total predicted by models were compared. Results: The results of both Penman and PT models gave the good Epan prediction. In addition, Penman models gave the very good statistical results. 2012 and 2013 Penman model gave the daily values of 0.52 and 0.70 R2, the monthly values of 0.98 and 0.96 R2 respectively. Conclusion: Finally, use of Penman model for evaporation estimate from dam, lake or any water mass is recommended in places with a humid climate such as Samsun.

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Class , A evaporation pan , Penman , Priestley , Taylor , PT , model , equation

The Journal Of Ege University Faculty Of Agriculture

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