abstract in recent years, automatic weather stations have been widely used for recording meteorological data in different time scales. therefore the accurate estimation of eto by combination equations can be evaluated using these set of short time scales data. daily eto can also be calculated by summation of hourly eto values. the purpose of this study is to compare the eto values estimated by ...

the intensity – duration – frequency (idf) curves play most important role in the hydraulic design of structures. the traditional method to construct idf curves has a long estimation process and also has high number of parameters which this property reduces the reliability of idf curves. in the traditional method, rainfall in different durations should be available until the extraction of idf c...

the hargreaves-samani (hs) equation, which estimates reference evapotranspiration (et0) using only temperature as input, should be most suitable for et0 prediction based on weather forecasting data. in the current study, the hs equation is calibrated with daily et0 by the penman-monteith equation, and is evaluated to check the possibility of predicting daily et0 based on weather forecast data. ...