Air quality indicators across Europe have continued to improve as emissions of regulated air pollutants decline, providing a clear indication of the success of long-standing air quality management policies, technological improvements and cleaner, more efficient industrial and transport systems.

The findings of the latest Assessment Report on European Air Quality 2025, published by the Copernicus Atmosphere Monitoring Service (CAMS), show that sustained efforts to reduce emissions from transport, industry, residential heating, coupled to environmental policies and advances in technology have steadily decreased emissions of major air pollutants.

Since 2015, emissions of sulphur oxides (SOx) and nitrogen oxides (NOx) have fallen by approximately 3–5 per cent per year across the EU, with the most significant reductions achieved in industry and road transport. Industrial emissions of SOx have fallen by 59 per cent, while NOx emissions from industry have declined by 39 per cent. Road transport emissions have also fallen substantially, with reductions of 40 per cent for NOx and 34 per cent for PM2.5.

Despite progress in cutting overall emissions, the report warns that environmental pressures are becoming an increasingly important factor in determining air quality outcomes across Europe.

According to the European State of the Climate 2025 report, 2025 was the third warmest year on record in Europe, while also characterised by pronounced regional differences. These conditions had important implications for air quality across Europe. High temperatures, intense sunlight and stagnant atmospheric conditions created favourable conditions for ozone formation during summer, while prolonged dry conditions contributed to severe wildfire activity in parts of southern Europe. Colder-than-average conditions also contributed to elevated particulate matter concentrations during winter, largely as a result of emissions from heating systems.

“The wildfires in August 2025 showed how closely these hazardous events are connected to air quality. In addition to elevating the levels of particulate matter at the surface level, the fire plumes also contributed to the increase in surface ozone levels in northern Portugal and Spain, because the release of significant amount of ozone precursors which react in sunlight as the smoke travels,” cautioned Paul Hamer, NILU senior scientist and main author of the report.

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