Variação temporal dos elementos climáticos e da ETo em Catalão, Goiás, no período de 1961-2011

In this study, the existence of trends in the temporal distribution of weather elements and reference evapotranspiration were evaluated, for the municipality of Catalao, in the State of Goias-Brazil. The Penman-Monteith method and a dataset of 51 years of daily weather parameters were used. The dataset was composed of daily maximum and minimum air temperature, insolation, wind speed, and relative humidity from 1961 to 2011. In order to identify monthly and yearly weather trends, statistical methods of Mann-Kendall, Sen Slope estimator, and linear regression with Student test were used. Due to increases in maximum and minimum temperature, as well as decreases in relative humidity, statistically significant increases in reference evapotranspiration were found for the months of September, October, December and the annual.