Comparison of experimental and data-based methods in estimating potential evapotranspiration in Zahedan city

Volume 6, Issue 2 - Serial Number 20
January 2024
Pages 199-214

Document Type : Original Article

Authors

1 water engineering department university of birjand

2 Water engineering Department, agriculture faculty, University of Birjand

3 Associate professor, Department of Water Engineering, Faculty of Agriculture, University of Birjand, Birjand, Iran.

Abstract
The process of evapotranspiration is an important parameter for evaluating and investigating hydrological phenomena and in issues related to the management of water resources in agriculture. In this research, 12 meteorological parameters related to Zahedan meteorological station, including minimum temperature, maximum temperature, average temperature, minimum humidity, maximum humidity, average humidity, rainfall, evaporation rate, sunny hours, wind direction, maximum wind speed and average wind speed were used. The methods include Artificial Neural Network, K-Nearest Neighbor, Priestley-Taylor, Hargreaves-Samani, Torrent-White and Penman methods have been used to evaluate the potential evapotranspiration values. For this purpose, R2, MAE and RMSE evaluation indices were used to compare the calculated evapotranspiration values with the observational values of potential evapotranspiration obtained from the evaporation pan (by applying the pan coefficient of 0.8). Based on the three indicators of MAE, RMSE and R2, ANN and Torrent-White methods showed the best and worst performance respectively in estimating potential evapotranspiration in Zahedan meteorological station. Among the experimental methods, the Hargreaves-Samani method showed better performance. Based on the evaluation results, data-based methods are more accurate than experimental methods in determining potential evapotranspiration.

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