Reference evapotranspiration estimated with limited climate data compared with alternative models in the semi-arid region - DOI: 10.7127/rbai.v1901383

Resumo

Accurate knowledge of reference evapotranspiration (ETo) is fundamental for the hydrological and agroclimatic planning of a region. Therefore, the objective of this study was to evaluate the estimate of reference evapotranspiration (ETo) by the Penman-Monteith-FAO (PM) model with limited data, and to compare it with alternative methods for the semi-arid region of Cariri, CE, Brazil. A period of climate data from 2021 to 2023 was used. For the evaluation, ETo was estimated by the PM method with all climatic data and compared with combinations of missing climatic data, and also with the alternative methods of Hargreaves and Samani, Jensen and Haise, and Makkink. ETo estimates were analyzed with statistical indices. According to the results, for the condition of missing solar radiation and wind speed data, the PM model can be used to estimate ETo for the study site. When the number of missing variables is increased, the error of ETo estimates also increases, reducing the accuracy of the models. If it is not possible to use the PM model, the Jensen and Haise model can be used to estimate ETo, since this method proved to be satisfactory and accurate.