Wildfires, heat waves pose growing threat to global air quality: UN weather agency

GENEVA: Increasingly severe wildfires and heat waves are threatening progress in improving air quality and protecting public health, the World Meteorological Organization (WMO) said on Monday, warning that climate change could make global air-quality targets harder to achieve.

In its annual report on air quality and climate, the United Nations weather agency said air pollution and climate change are closely connected and should be addressed through coordinated policies rather than as separate challenges.

The WMO warned that achieving the World Health Organization’s air-quality guidelines could become more difficult as climate change increases the likelihood of extreme wildfires.

Wildfires are also emerging as a larger source of hazardous air pollution, even as tighter regulations have helped reduce emissions from industrial activity and transport in many developed countries, the report said.

The agency called for coordinated action on both air pollution and climate change, highlighting the growing impact of wildfire smoke and extreme heat on air quality and human health.

“No matter how clean your city or your region is … if you have a lot of pollution brought about by wildfires, that has the potential to negatively impact air quality in those regions as well,” Lorenzo Labrador, scientific officer at the WMO, told Reuters.

The report highlights the growing impact of fine particulate matter, known as PM2.5, and ground-level ozone, pollutants linked to respiratory and cardiovascular disease. It also calls for improved monitoring of pollutants and aerosols including black carbon and microplastics, which it said remain poorly tracked despite their widespread presence in the atmosphere.

This year has been marked by extreme heat and destructive wildfires across parts of Europe, including Spain, France and Greece. The WMO has said extreme heat is becoming more frequent, intense and longer-lasting as the planet warms.

The new report said PM2.5 concentrations in 2025 were above long-term averages in northern Canada, parts of Russia and western-central Africa due to heightened fire activity, while northwestern Spain was a hot spot following exceptional late-summer fires.

A study cited in the report found extreme fire-smoke events have tripled globally since the 1990s and may have contributed to nearly 100,000 additional deaths annually between 2010 and 2018.

Particulate matter from wildfires is particularly harmful because it comes with a host of toxic chemicals, Labrador said, adding that inhalation causes body-wide inflammation that can lead to pulmonary disease.