Global Air Pollution Data for Health Risk Assessments in Lombardy, Italy

Air pollution figures among the top 10 of the Disability Adjusted Life Years (DALY) risk factors. Poor air quality particularly impacts the urban population. In 2021, in Europe, 91% of it was exposed to pollutants' concentrations above the 2021 World Health Organization (WHO) air quality guidelines (WHO, 2021a). For this reason, performing a health risk assessment due to the exposure to air pollution is important to support policy makers and to guide the implementation of mitigation measures. Several data sources of surface air pollution concentration are available today, especially for high-income countries. However, each of them brings strengths and weaknesses in terms of spatiotemporal resolution and coverage. Moreover, data are lacking in many regions of the world. With this study, we present an evaluation of the performance of the European Centre for Medium-Range Weather Forecast (ECMWF) Copernicus Atmosphere Monitoring Service (CAMS) global reanalysis dataset (EAC4), with coarse resolution and worldwide availability, with those of the ECMWF-CAMS European Reanalysis, with higher resolution. This is done in sight of an application of these data to perform a health risk assessment due to a long-term exposure to NO2, PM2.5 and O3. Data aggregates are put in relation to the Fraction of Settled Area (FSA) of the World Settlement Footprint and diurnal variability of the species' concentrations. The geographical area of this study is the highly urbanized Lombardy region in northern Italy. However, the results are discussed with respect to global applicability