Avaliação do modelo de reanálise GLDAS/NOAH e obtenção de fluxos de energia a partir do SEBS, em Minas Gerais

Abstract

In this study, we analyzed a model that estimates energy flows on soil surfaces and current daily evapotranspiration in the state of Minas Gerais, Brasil, in 2010. The flow of sensible heat, solar radiation and current daily evapotranspiration were estimated by means of the Surface Energy Balance System (SEBS), based on the energy balance equation, using image data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, Global Land Data Assimilation System (GLDAS), Instituto Nacional de Meteorologia (INMET) and Integrated Land and Water Information System (ILWIS) freeware. We also evaluated other SEBS input data variables: near surface specific humidity, near surface wind speed, near surface air temperature and surface pressure, originated of the GLDAS/Noah product. To do this, we created a batch file that allowed the extraction of information from 11,680 images and the calculation of the daily and monthly mean of each variable. The results obtained were compared to the data of 46 INMET meteorological stations using correlation coefficient, mean bias error and root mean square error. The presence of clouds over the study area allowed for the use of SEBS on only ten days, generating current daily evapotranspiration, solar radiation and sensible heat flow maps for days 02/23, 06/22 and 08/27, which better allowed the visualization of the spatial distribution of these variables.