Scenarios over the past 3 decades: air quality impact of European legislation

Abstract:

The impacts of air pollution span from local to global, affecting human health, climate, visibility and ecosystems. Several actions at national, regional and global scale have been adopted to reduce pollutant emission levels. In our work we make use of the EDGAR_ v4.3 emission database to compare today’s pollutant levels with ex-post scenarios developed to assess the impact and effectiveness of legislation over the last 3 decades on air quality and climate. Differently from most of literature works addressing future air quality, here we focus on historical global anthropogenic emissions (years 1970-2010) of several gaseous and particulate air pollutants (SO₂, NOx, CO, NMVOC, NH₃, PM₁₀, PM_2.5, BC and OC) and past emission scenarios to demonstrate the role that policy has played in improving air quality. Three scenarios have been developed and compared to today’s situation (year 2010), assuming the lack of abatement measures, the complete stagnation of technology (no reduction measures applied and constant emission factors from 1970), and a constant fuel mixture (with a more prominent role for coal in the 1970s).

Special focus is dedicated to the power generation sector, manufacturing industry and road transport activities since these were mostly influenced by official regulations in the EU. Global SO₂ emissions from transport dropped down by 8.5 times due to the deployment of low S content fuels; NOx and CO emissions are indeed a function of combustion efficiency and therefore decreased with the introduction of new technologies, while NH₃ emitted by road transport increased in Europe by 18% due to the introduction of catalyzers. Finally, particulate matter emissions are mainly abated by the installation of End-of-Pipe measures (e.g. filters) especially in the energy and transport sectors.