Aplicação do algoritmo SAFER na obtenção da evapotranspiração da caatinga no Estado do Rio Grande do Norte utilizando imagens MODIS.

Abstract

The main objective of this work was to estimate and validate the Evapotranspiration (ET) and the seasonality of the energy balance for the State of Rio Grande do Norte, using micrometeorological data and orbital data from the Simple Algorithm for Retrieving Evapotranspiration (SAFER) algorithm applying MODIS images in temporal and spatial scale and measuring surface data (in situ) at the ESEC (Seridó Ecological Station) located in the municipality of Serra Negra do Norte - RN and contrasting with global ET data (MOD16A2 and GLDAS). The behavior of some biophysical variables for different soil uses was also analyzed. The results showed that the temporal variability of the ET adjusts to the climatic seasonality of the region, allowing the identification of the spatial occurrence of the ET, demonstrating its sensitivity to different types of land use and occupation especially in relation to the radiation fluxes available in the area studied. The results indicate that the ET estimated by SAFER Algorithm obtained better correlation between the other methods compared to MOD16A2 and GLDAS, which obtained a value of 0,654. The methodology used by remote sensing showed that through the estimates of temporal and spatial distribution proved the efficiency of this method, being possible to estimate the volume of water emitted to the atmosphere through Evapotranspiration.