Abstract: In recent decades, extreme events resulting from climate change have been occurring more frequently and with greater intensity worldwide, causing serious consequences for agriculture and the economy. In order to mitigate these extreme events, it was proposed during the COP 21 meeting in Paris that the countries involved in this group commit to reducing their greenhouse gas emissions (GHGs) and to seek new tools and technologies primarily utilizing clean energy. Brazil was one of the countries that participated in this agreement. Subsequently, the State of Espírito Santo officially joined the UN’s “Race to Zero” campaign, committing to take actions aimed at neutralizing GHG emissions by 2050. The focal point of this project is the Espírito Santo Decarbonization and Greenhouse Gas Emission Neutralization Plan, which outlines strategies and instruments of public policies to achieve the decarbonization goal by 2050. Among these decarbonization strategies is a plan to electrify the automotive fleet as one of the envisaged strategies for neutralizing the State’s emissions. However, there is still a gap regarding the feasibility and actual environmental gains of this strategy.In this context, a research project was developed using a photochemical air quality model to assess the impacts of electrifying the vehicle fleet on air quality in the Greater Vitória Region, the metropolitan area of the state of Espírito Santo, Brazil. This involved comparing the current scenario of pollutant emissions solely from vehicles in the region with a hypothetical scenario considering the total electrification of the vehicle fleet in the region.The Weather Research & Forecasting (WRF) model was used to simulate meteorological data for the year 2016, the year the emission inventory was conducted. The Community Multiscale Air Quality (CMAQ) model was utilized to estimate concentrations of pollutants linked to GHGs, such as tropospheric ozone. The official emission inventory of the Greater Vitória Region, published by the local environmental agency (IEMA), was employed as the base emissions scenario, while the electrification scenario was built based on this baseline. Ozone (O3) contributes approximately 8% to global warming and is formed through photochemical reactions in the atmosphere involving precursors such as hydrocarbons and nitrogen oxides emitted predominantly by combustion processes like vehicle engines. Therefore, ozone was chosen as the pollutant for analysis in this study. The results indicate that when emissions from mobile sources are removed from the inventory, ozone emission rates are higher compared to the baseline scenario. This is likely associated with the NOx-limiting characteristic of the Greater Vitória Region, as indicated in a previous study on ozone formation potential in the region. Thus, reductions in NOx emissions may favor the O3 formation cycle via direct reaction between OH radicals and VOCs.

Keywords: Climate change, Greenhouse Gas Emissions (GHG), Vehicle Fleet Electrification, CMAQ Model, Ozone Increase.