- Lastly, WDEL depends on various factors, such as relative humidity, air temperature, wind speed, pressure head at the nozzle, drop diameter, and riser height \citep{Tarjuelo_2000}. On the other hand, night watering is not common in the region, and most irrigation takes place during daylight hours. Therefore, based on the findings of previous studies \citep{Sarwar_2019,o2008}, the amount of wind drift and evaporation lost in the study area was considered to be equal to 20%.
Based on the assumptions mentioned above, the sprinkler irrigation systems development in the study area has led to estimated annual wind drift and evaporation losses. According to Table \ref{403523}, 336.1 million cubic meters of water, in 16 years upstream of the Eskandari station evaporated and left the watershed due to wind drift and evaporation losses. This estimation was consistent with the overall decrease in flow volume within the study area, as indicated by the decrease in aquifer storage and the positive trend observed in the Cheshmeh-Langan tunnel, as shown in Table \ref{642548}.