MONTHLY ANALYSIS, SEASONAL AND INTERANNUAL OF POTENTIAL EVAPOTRANSPIRATION TO THE EAST OF THE STATE OF ACRE, BRAZIL

The aim of this study was to investigate climatological aspects (characterization) in seasonal potential evapotranspiration east of Acre, with the unit of study is the city of Rio Branco, capital of the State, considering a period of 34 years from 1980 to 2013, from monthly data from a weather station in a conventional surface. The methodology was adopted to realize the consistency of meteorological data in this way, first, was made the gap filling through the imputation of missing data in time series by means of Multivariate Time Series Data imputation and statistical tests of homogeneity of data (test or Run sequence) suggested by the World Meteorological Organization through its technical note 81 the indirect method Penmann-Montheith was used to calculate the potential Evapotranspiracao. The results of this work through examination of the descriptive statistics showed that the average annual ETp is 3.54 mm d -1 , with a very marked seasonality in June featuring a minimum of 2.93 mm d -1 and a maximum in October from 4.13 mm d -1 with an average annual accumulated 1290.99 mm and Standard Deviation of 53.41 mm and the months of June and August are what have higher variability and the interval from October to February the lowest variability.