@article{article_1116199, title={Probabilistic Analysis of Variability in Reference Evapotranspiration}, journal={Journal of Agricultural Faculty of Gaziosmanpaşa University}, volume={39}, pages={92–96}, year={2022}, DOI={10.55507/gopzfd.1116199}, author={Yürekli, Kadri}, keywords={Reference evapotranspiration, ITA approach, frequency analysis}, abstract={The amounts of hydro-meteorological data have varied over time due to human-induced global climate change. Obtaining the data to be used in the estimation of the crop water consumption parameter, which is of vital importance especially in the context of agricultural water management, under stationary conditions is a necessity in terms of reliability. The differentiation of data over time means that its frequency distribution behaviour also changes. The main goal of this study was on this change in question. For this purpose, annual reference evapotranspiration (ETo) values of Amasya and Samsun stations were used as material. The change in ETo data was analyzed with the ITA and PITA approaches. The ITA analysis regarding the Amasya station showed a statistically increasing change in the ETo data, whereas there was no statistically significant change for the Samsun station. Probability distributions fit most approximate to the data sequences of the first halve (FH) and second halve (SH) obtained by dividing the full data according to the PITA technique were Gama and Gumbel for the Amasya station, respectively. The normal distribution was found for two halves of the Samsun station. This finding confirmed that the data of the Amasya station has changed statistically over time. Remarkable differences were detected in the quantiles at especially higher risk levels for the Amasya station.}, number={2}, publisher={Tokat Gaziosmanpasa University}, organization={***}