SIQUEIRA, M. S.; http://lattes.cnpq.br/0754929803491263; SIQUEIRA, Mariana da Silva de.
Abstract:
Evapotranspiration - ET is an important term in the water cycle that integrates atmospheric
demands and surface conditions and one of the main variables of the hydrological cycle, as the
main responsible for the loss of water in hydrographic basins, ET has a great influence on the
hydrological processes. The main objective of this study was to evaluate the performance of the
SWAT Soil and Water Assesssment Tool hydrological model in the simulation of
evapotranspiration estimates for the Piranhas-Açu River Basin (BHRPA) in the state of Rio
Grande do Norte, Northeast semiarid region Brazilian. The results of the hydrological
simulation allowed to analyze the behavior and seasonal variability of ET on a basin scale. The
SWAT model was used without calibration and presented a good performance in the ET
simulation, offering coherent information when compared to those estimated by the water
balance method - BH, indicating that it has an expressive potential for continuously monitoring
the spatial ET, that can be used to determine the behavior of the hydrological cycle. The ET
values of the simulation with the SWAT and of three more products of estimates of different
methods were compared with estimates by the method of BH for localities inserted in the
BHRPA, the spatial distribution of the average of the annual accumulated values of the
simulation for the components was also performed hydrological. The ET estimates for the
period from January 2002 to December 2011 used in this work are derived from hydrological
simulation with SWAT, from global scale ET products MOD16 (Moderate resolution Imaging
Spectroradiometer) and GLDAS (Global Land Data Assimilation System) and the regional R-
SSEB model (Simplified Modeling for Power Balance estimate the area in regional Scale).
Despite the differences between the ET from the evaluated methods and the one calculated by
the BH method, in general it was possible to identify that the simulation with the SWAT model
showed more coherent evapotranspiration results, indicating an expressive potential for spatial
monitoring of the ET continuously. Considering the spatial distribution of the averages of the
annual accumulated hydrological components, through hydrological simulation, described in
the work, it is concluded that there may be possible interferences of vegetation cover, use and
types of soil in the evapotranspiration process, as well as influences of evapotranspiration in
the hydrological components simulated with SWAT.