Traffic and PM10 in Veneto region (northeastern Italy): The lesson of the 2020 lockdown

The COVID-19 lockdown in 2020 represented a unique opportunity to evaluate the way reduced traffic may influence air pollution levels. In the present study, this analysis is performed in the Veneto region, northeastern Italy, one of the most polluted areas in Europe, in the eastern Po Valley. During the first month of the COVID-19 lockdown period, the concentrations of fine particles (PM10) fell by 20–25% in the area, which corresponded to a 30–40% decrease in NO 2 emissions, mostly attributed to lower traffic volumes. In order to understand if the specific atmospheric conditions of the period affected the decrease in PM10 concentration, meteorological data from ground stations and radio-soundings, together with ERA5 reanalysis data, were analysed to better define the role of meteorology in the reduced pollution concentrations. The analysis does not identify significant changes in the meteorological conditions. The improvement in the concentrations of PM10 during the lockdown period emphasizes the potential benefits of traffic reduction in achieving air quality goals. Unfortunately, current policy plans are insufficient, failing the 39% reduction in traffic emissions declared as necessary by the Veneto region to comply with EU standards. This consideration highlights the urgent need for significant changes in traffic management strategies in the region.