Publication Date:
2023-07-07
Description:
We present an intercomparison of different regional atmospheric chemistry model simulations over the Metropolitan Area of São Paulo (MASP), analyzing the capacity and limitations of those models to simulated secondary aerosol production, which plays a fundamental role to well represent PM2.5 and PM10 concentrations over the area. It has been shown in the past that secondary aerosol production in the MASP is generally underestimated by the models. Secondary aerosols in the MASP mainly form from precursors emitted by extensive vehicle emissions from a fleet using a high percentage of biofuels. Also, the MASP’s atmosphere is affected by pollution from biofuel burning in thermoelectrical plants around the city, apart from distinct remote biomass burning activities from the Amazon and Cerrado biomes in central Brazil, sugarcane burning in the state of São Paulo and, more recently, also from fires in the Pantanal wetland in the southwest of the country. Model results were evaluated with available observations from the state’s monitoring network and available campaign data. An ensemble run shows that the capacity of all models together generally improves the simulated results for ozone and other relevant species, despite the low number of ensemble members. However, PM2.5 is constantly overestimated by an order of 10 ug/m2. We analyze by which means the secondary aerosol calculations may be improved by the models to reduce uncertainties of future particulate air quality estimates, and to which extent the uncertainty in estimates of primary emissions from biomass burning may also still play a role in this.
Language:
English
Type:
info:eu-repo/semantics/conferenceObject
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