Estimated evolution of total pollutant gas emissions associated with vehicle activity in the Metropolitan Region of Porto Alegre until 2030.

In recent years, the majority of economic sectors in Brazil have gone through processes of development and transformation. These processes have led to increases in environmental pollution of all kinds; air pollution being one of the most adverse. The Brazilian transportation sector, which heavily affects the air quality, experienced a significant increase in its vehicle fleet thus provoking larger emissions of pollutant gases, mainly in regions with high population density such as the Metropolitan Region of Porto Alegre (MRPA). Within this research, considering mainly the ozone precursor species and Carbon Monoxide and using the year 2001 as a base year, scenarios are obtained for vehicular emissions of pollutant gases in the MRPA until the year 2030. In addition, scenarios related to the evolution of the study region's vehicle fleet were estimated. The statistical tool LEAP (Long Range Energy Alternatives Planning System) was used. The scenario analysis shows that the vehicle fleet will grow exponentially until 2030, considering that the Light Flex vehicles category will mainly contribute to this increase. It is also noted that vehicle emissions of CO, NOx, and THC decrease in the region. The decrease is caused mainly by the renewal of technology in new vehicles and the implementation of emission control programs created by the government.