Modelagem e assimilação de aerossóis atmosféricos sobre São Paulo - Brasil com o modelo de transporte químico regional EURADIM em alta resolução

Abstract

A high-resolution air quality study over the Metropolitan Area of São Paulo (MASP), Brazil is presented using the EURopean Air Pollution Dispersion - Inverse Model (EURAD-IM) for a highly detailed simulation of the air pollution plume interactions. In these first case studies on particulate matter (PM2.5 and PM10) modeled data are evaluated with observational in-situ data from 24 surface stations from the Environmental Company of the State of São Paulo (CETESB) and a Lidar. The two presented case studies, focusing on July 10-13 and October 22-25, 2016, show how different meteorological conditions affect the transport of pollution plumes over the MASP originating from (i) central South America, associated to biomass burning activities, (ii) from the interior of the state of São Paulo (SP), (iii) the metropolitan region of Rio de Janeiro (RMRJ) 429 km apart, including transportation in the opposite direction, (iv) the port and city of Santos, as well as Campinas and contrary direction. Three simulations were carried out, the first using the emissions inventory of EDGAR v4.3.2, the second replacing the category of land transport emissions with data from the Vehicle Emissions Model (VEIN) with high spatial resolution and the third using the three-dimensional variational data assimilation technique (3D-VAR) for PM2.5. The performance of the model varied from excellent to good agreement with the observations varying within the standard deviations and elucidated the role of long-range transport of particulate matter from central South America and local transport within the state of SP, affecting the air quality at MASP. For the period from July 10-13, the results of PM10 and PM2.5 in the simulations without assimilation for the domain with 1 km x 1 km resolution underestimated the observations, and the bias varied between 8 - 41%. For MASP center, EURAD-IM performed better using VEIN emissions. The second case study in October revealed that air pollution plumes from the MASP and MARJ interact with each other, through two possible routes: via the Vale do Paraíba or via the ocean between the coast of Rio de Janeiro and São Paulo. For October 22-25, EURAD-IM performance was more accurate outside the city of SP where the simulation underestimated observations, and the bias varied between 2 - 41%. EURAD-IM 3D-Var scheme was adapted and used in the MASP for first time. The assimilation significantly reduced errors, which improved the subsequent performance of PM2.5 during July 10- 13.