Seasonal Impacts of Atmospheric Aerosols on Reference Evapotranspiration in the Mato Grosso Cerrado

Atmospheric aerosols significantly influence climate systems and hydrological processes, but their impacts on evapotranspiration remain insufficiently understood, particularly in tropical savanna regions. This study investigates the direct and indirect effects of aerosol optical depth (AOD) on reference evapotranspiration (ET0) in the Mato Grosso Cerrado, Brazil, a biome characterized by pronounced seasonal climatic variations. Using data collected from the AERONET network at Fazenda Miranda, AOD was analyzed alongside meteorological variables such as air temperature, global radiation, and ET0, estimated using the FAO Penman–Monteith method. The results reveal distinct seasonal patterns, with aerosols having a more pronounced influence during the dry season. Positive correlations were observed between AOD and air temperature, while negative correlations were found between AOD and global radiation, especially during the dry season. The relationship between AOD and ET0 varied between years and seasons, with significant reductions in ET0 linked to high aerosol concentrations during the dry period. These findings demonstrate that aerosols play a critical role in modulating evapotranspiration and radiation balance, particularly in regions affected by biomass burning. This study provides valuable insights into the interplay between aerosols, climate variables, and hydrological processes, contributing to a better understanding of aerosols’ impacts on tropical ecosystems.