Europe’s Air Quality improves as emissions decline: CAMS Report

Brussels: Europe is making steady progress in improving air quality, with sustained reductions in emissions from transport, industry and energy sectors, according to the Assessment Report on European Air Quality 2025 released by the EU’s Copernicus Atmosphere Monitoring Service (CAMS).

However, the report warns that increasingly frequent heatwaves and wildfires driven by climate change continue to undermine these gains by triggering dangerous episodes of ozone and particulate pollution.

The report says that although some parts of Europe continue to experience local air pollution problems, the overall outlook for air quality across the continent “remains encouraging.” The findings come as the European Union works to align its air quality standards more closely with the recommendations of the World Health Organization (WHO) under the revised Ambient Air Quality Directive.

According to CAMS, emissions of sulphur oxides (SOx) and nitrogen oxides (NOx), two of the most harmful air pollutants—have declined by around three to five per cent annually across the European Union since 2015. The largest reductions have been achieved in industrial activities and road transport.

Industrial SOx emissions have fallen by 59 per cent, while NOx emissions from industry have declined by 39 per cent. Road transport has also registered significant improvements, with NOx emissions dropping by 40 per cent and fine particulate matter (PM2.5) emissions declining by 34 per cent.

The report attributes much of this progress to stricter emission controls, cleaner technologies and the growing adoption of electric vehicles. Europe’s transport sector, which remains responsible for nearly one-third of the EU’s total emissions, emitted 1.05 billion tonnes of carbon dioxide in 2024, down from 1.1 billion tonnes in 2019, a reduction of about five per cent.

The transition towards renewable energy is also contributing to cleaner air. For the first time, more than half of the EU’s net electricity generation came from renewable energy sources during the second quarter of 2025. Sweden led the bloc by generating 99 per cent of its electricity from low-carbon sources last year.

Despite these improvements, CAMS cautions that climate-related extreme weather is creating new air quality challenges.

The report notes that prolonged heatwaves, high temperatures, intense sunlight and stagnant atmospheric conditions favour the formation of ground-level ozone, a harmful pollutant that damages human health and vegetation. Elevated ozone concentrations were recorded during the severe heatwaves that affected much of Europe in June and August last year.

Unlike the protective ozone layer high in the atmosphere, ground-level ozone forms through chemical reactions involving nitrogen oxides under strong sunlight. Exposure to elevated ozone levels can damage lung tissue, aggravate respiratory diseases and harm crops and ecosystems.

The report also highlights the growing impact of wildfires on air quality. Record wildfires that burned between 11 and 19 August last year severely affected Portugal and Spain, causing widespread exceedances of daily PM2.5 air quality limits across parts of the Iberian Peninsula.

Smoke from the fires not only increased concentrations of fine particulate matter but also boosted surface ozone levels by releasing ozone-forming pollutants into the atmosphere.

“Europe continues to make steady progress in improving air quality thanks to sustained efforts to reduce emissions from transport, industry, residential heating, and other key sectors,” said CAMS Director Laurence Rouil.

The report’s author, Paul Hamer, stressed the close relationship between climate extremes and air pollution.

“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 of the release of a significant amount of ozone precursors which react in sunlight as the smoke travels,” he said.

The report concludes that while Europe has made measurable progress in reducing harmful emissions, continued efforts to decarbonise transport and energy systems, alongside stronger adaptation measures to address heatwaves and wildfires, will be essential to sustain improvements in air quality.