Modelagem espaço-temporal da evapotranspiração de referência na Bacia Amazônica em um cenário de crescimento na emissão de gases do efeito estufa

Abstract

Global climate change presents numerous risks to natural ecosystems, altering important climatic variables in several regions of the globe, including the Amazon Forest. With the greatest biodiversity on the planet, the Amazon Forest influences the climate patterns of other regions in Brazil and Latin America. Among the climatic variables affected by climate changes in the Amazon Forest is evapotranspiration, an important regulator of the Amazonian hydrological cycle. Changes in evapotranspiration may result in a climatic imbalance not only in the Amazon region, but also in other regions, which is why it is important to understand these changes. The main objective was to estimate the values of evapotranspiration in the Amazon Basin under a rigorous climate change scenario, providing a tool for the spatially explicit modeling of evapotranspiration. Using the outputs of the Hadgem2-es climate model, derived from CMIP5, the reference evapotranspiration values for the Amazon Basin were estimated using the Penman-Monteith (FAO) method until the year 2050. Under an extreme emission scenario carbon in the atmosphere (RCP 8.5), an increase in evapotranspiration values was identified in the Amazon Basin until the middle of the century, mainly in the northeast region of the basin extending to the southwest. The annual seasonality remained similar to the current one, with an increase in evapotranspiration during the dry season and a decrease during the rainy season, following the seasonality of temperature values and radiation balance. A better representation of the complex relationship between climate and forest can be achieved by using spatial data for use and occupation of the Amazonian soil projected for the future. The developed model proved to be effective in evapotranspiration calculations, showing results consistent with those observed in the consulted bibliography. In order to avoid climatic imbalance in the Amazon Forest and consequently in other regions, joint government actions are necessary in order to mitigate the growing emission of greenhouse gases into the atmosphere.