Abstract:
Evapotranspiration (ET) can be identified as a key function of vegetation which develops
interaction in between climatologic, hydrological and terrestrial environments. Though there are
number of climatologic methods are available to calculate ET such as Penman-
MonteithMethod(PMM), Blany-Criddle Method(BCM), Radiation Method (RM), Hargreaves- Samani
Method(HSM), Linacre Method(LM), Makkink Method(MM) and Turc Method(TM),in practice Penman-
Monteith Method is used since it is likely to provide the most satisfactory result. But, it is not easier to
obtain all types of climatic data since malfunctioning ofweather stations.However, the method
selected to estimate ET should produce reasonable result with minimum number of climatic data.
Thus, this attempt was taken in order to identify the most suitable method to utilize in various months
to calculate ET considering the quality of result and input data requirement.According to the obtained
results both Hargreves- Samani and Linacre Methods have shown reasonable values to replace
PMM. Therefore Irrigation demand can be predicted and will be able to plan fairly successful irrigation
scheduling in the field.
