Europe is making steady progress in reducing air pollution, but increasingly frequent heatwaves, wildfires and other climate-related events are creating new health risks and threatening decades of environmental gains, according to a major assessment released Wednesday.
The European Air Quality Assessment Report 2025, published by the Copernicus Atmosphere Monitoring Service (CAMS), found that emissions from industry and transport continued to decline across Europe in 2025. However, extreme weather events fueled dangerous spikes in ozone and particulate pollution, exposing millions of people to unhealthy air.
“Europe continues to make steady progress in improving air quality thanks to sustained efforts to reduce emissions,” said Laurence Rouil, Director of CAMS. But she warned that the combination of remaining emissions and changing weather patterns can still trigger “significant large-scale episodes” of air pollution.
The report shows that since 2015, emissions of sulphur oxides (SOx) and nitrogen oxides (NOx) have fallen by about 3% to 5% each year across the European Union. Industrial SOx emissions dropped by 59%, while road transport cut NOx emissions by 40% and fine particulate matter (PM2.5) by 34%.
Researchers say the reductions demonstrate that environmental policies have successfully decoupled economic growth from air pollution by encouraging cleaner industrial processes, vehicles and energy systems.
But the report warns that climate change is increasingly shaping air quality.
Europe experienced its third warmest year on record in 2025. During a major heatwave in August, stagnant atmospheric conditions across western and southern Europe created ideal conditions for the formation of ground-level ozone, a pollutant that can damage the lungs, aggravate respiratory disease and reduce crop yields.
At the same time, record-breaking wildfires in Portugal and Spain sent vast plumes of smoke across the Iberian Peninsula, causing widespread exceedances of health guidelines for PM2.5.
For the first time, CAMS scientists used advanced source-attribution techniques to estimate how much wildfire smoke contributed to local pollution episodes.
“The fire plumes also contributed to the increase in surface ozone levels because of the release of significant amounts of ozone precursors which react in sunlight as the smoke travels,” said Paul Hamer, a senior scientist at NILU and the report’s lead author.
Winter also brought challenges. Colder-than-average temperatures in Eastern Europe increased emissions from residential heating, pushing particulate pollution to unhealthy levels in several regions.
Natural events further complicated Europe’s air quality. In March 2025, a large Saharan dust intrusion carried mineral dust across southern, western and central Europe, causing repeated exceedances of PM10 air quality standards. Although naturally occurring, the dust still poses health risks because elevated concentrations of coarse particulate matter can worsen respiratory conditions.
The report concludes that while Europe has made substantial progress in reducing emissions through environmental regulation, future improvements in air quality will increasingly depend on adapting to a changing climate as well as continuing to reduce pollution at its source.
The findings are consistent with growing scientific evidence linking climate change to worsening air pollution episodes. A 2024 review published in the European Environment Agency found that heat, drought and wildfires are becoming increasingly important drivers of poor air quality across Europe, while research published in the The Lancet has warned that climate change is amplifying exposure to harmful air pollutants and increasing the burden of respiratory and cardiovascular disease.
