Validação dos dados da espessura ótica dos acrossóis dos sensores MODIS e OMI e do modelo MERRA-2 através dos dados observados da AERONET

Abstract

Of the variables related to air pollution, aerosols are one of the main factors responsible for affecting the radiation balance, causing changes in the atmosphere resulting in long-term climate changes. Since their characteristics are very varied, their distribution in the atmosphere are heterogeneous, making the measurement means specific, there are some ways to study these characteristics and / or properties, one of which is the analysis of the Optical Thickness, which is responsible for quantifying the radiation attenuation in a medium containing optically active material, so remote sensing is one of the most effective tools. This study aims to compare data on aerosol optical thickness from three different sources to the surface data from AERONET (Aerosol Robotic Network), two of them obtained through remote sensing from MODIS (Moderate-Resolution Imaging Spectroradiometer) and OMI (Ozone Monitoring Instrument) and the third using reanalysis data from MERRA-2 (Modern Era Retrospective-Analysis for Research). For this, the independente observations from 4 stations of the AERONET will be used, evaluating the quality of optical thickness of other data sources through statistical methods such as BIAS, RSME and Pearson, the main areas with the highest values over South America for the period were observed 2005 to 2019 and pointed out possible reasons for the results obtained. Of the three data sources used in the comparison with what was observed, the MODIS sensor was highlighted by presenting the best results. The OMI sensor obtained two of the worst correlations observed throughout the study, always overestimating the station data. The AERONET station where the 3 data sources has obtain the best correlations was Alta Floresta. On the other hand, the one that obtained the worst results was the CEILAP RG station.