Abstract

This study aimed to was evaluating the performance of 30 methods to estimate reference evapotranspiration ET0 to the city of Parana ba Brazil The meteorological data was removed from National Institute of Meteorology on the period of six year March 2008 to February 2014 The method taken as standard was Penman-Monteith-FAO56 and the comparison of results was by the coefficients of determination r coefficients a and b of the linear regressions estimate of standard-error Willmott s index of agreement d Pearson correlation coefficient r and reliable coefficient c The better methods to ET0 estimate was Penman-Original Stephens-Stewart Priestley-Taylor Hicks-Hess Turc Liquid-Radiation Thornthwaite-Modified Temperature-Radiation Penman-FAO24 Abtew and Camargo The Camargo method should be preferred when only air temperatures data have The methods Blaney-Criddle-FAO24 and Hamon should receive calibration for be utilized on the estimate of ET0 in Parana ba city