Numerical modeling of potential evapotranspiration using WRF regional model – Urmia Lake basin case study

Document Type : Research Paper


1 PhD student, Atmospheric Science & Meteorological Research Center (ASMERC), Tehran, Iran

2 Assistant Professor, Atmospheric Science & Meteorological Research Center (ASMERC), Tehran, Iran


In this study, by introducing a novel approach and developing the required programs and codes, the standard FAOPenman-Monteith method is applied on the output of WRF (Weather Research and Forecasting) model, and the daily potential evapotranspiration has been calculated for a month of the study period, from 23th June to 23th July of the year 2017. The calculated values have been validated by the measured station data. The results showed that despite of the underestimation of the model outputs for the reference evapotranspiration, WRF model generally had a good performance with rational outputs on the locations of the stations as well as the whole simulation domain. Hence, model WRF could be considered as a precious tool in operational forecasting for agro-meteorological needs. Errors are expected due to various reasons; such as stationary land surface data which are not updated and the effect of spatial resolution in atmospheric simulations of the model. The results of this research could manage the agricultural water consumption by predicting the future values of daily potential evapotranspiration which is important in estimation of crop water requirement.


Main Subjects

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