Fundamental Research Division
The DRF at the CEA assemble approximately 6,000 scientists since January 2016.
Scientific result | European ＆ international partnerships | Environment
Should countries reduce their greenhouse gas emissions to meet their December 2015 pledges at COP21, global temperatures would expected to rise by about 3°C by 2050 with respect to pre-industrial climate. For the first time, an international team of LSCE researchers has studied the impact of such a scenario on the air quality in Europe in 2050. Their results show that current efforts to reduce European anthropogenic emission reductions would probably be annihilated.
Unlike stratospheric ozone, which protects us from UV light, atmospheric low-level ozone is a pollutant affecting the respiratory system. It is produced under the effect of solar radiation from industrial pollutants that are by-products of incomplete combustion.
For the past few decades, European regulations to limit emissions of ozone precursors have resulted in improved air quality, and could potentially continue to bear fruit by 2050. This study however shows that climate change and the accompanying polluting emissions from outside Europe are changing the game.
In the case of a 2 °C temperature rise by 2050, this policy will no longer allow to improve air quality in Europe. With +3 °C, the air quality would deteriorate sharply, especially in south-eastern Europe, where the health of populations could be seriously exposed—100 days per year on average, instead of 25.
These results were obtained as part of a European project, from computer simulations using a cascade of atmospheric chemistry and climate models. According to the sensitivity tests carried out, the decrease in air quality is mainly driven by the increase in ozone concentrations on a global scale. Under the +3 °C scenario, climate experts report doubled global methane concentrations, a gas which, on top of its strong greenhouse effect, is an ozone precursor.
According to this study, preserving air quality will need more than sustaining the efforts to reduce polluting gas emissions in Europe—it will also require bolstering climate policies. For example, a reduction in global methane emissions would have beneficial effects, both for global warming mitigation and air quality improvement.
A 3°C global RCP8.5 emission trajectory annihilates benefits of European emission reductions on air quality, Nature Communications.
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.