“The high emissions caused by these fires have the potential to affect not only Spanish cities but also the rest of Western Europe and the entire continent,” stated the chief scientist of the World Meteorological Organization (WMO).
In a press conference, Lorenzo Labrador emphasized that the impact of emissions caused by fires—which have affected up to 1% of the Iberian Peninsula—often crosses borders.
The expert recalled last year’s wildfires in Canada, the effects of which on air quality were also felt in Europe, crossing the North Atlantic.
Labrador also mentioned that wildfires are a permanent source of the most polluting and harmful atmospheric particles, those with a diameter of less than 2.5 microns (known as PM2.5).
The expert made these remarks while presenting the annual edition of the WMO’s air quality bulletin, which compiles data from 2024.
The report indicates an increase in pollution from PM2.5 particles, particularly in South America due to wildfires affecting regions like the Amazon, as well as in Canada, Siberia, and Central Africa under similar circumstances.
Conversely, this type of pollution has decreased again in eastern China, where cities like Beijing were once among the most polluted in the world, but where systematic mitigation measures have yielded positive results.
The report also examines variations in aerosol presence (small suspended particles), with some types contributing to global warming while others produce cooling.
For example, aerosols produced by sulfur emissions have decreased over the years thanks to measures taken to reduce their presence in fuels, something that has improved air quality and reduced premature deaths and childhood asthma.
However, this reduction has also contributed to an increase of 0.04 degrees Celsius in global temperatures by 2025, Labrador indicated, since these aerosols reflect part of solar radiation.
The UN agency also highlights the rise in smog episodes, or pollution fog, in winter in many regions of the world, including the densely populated north of India, warning that “they are not merely a seasonal meteorological phenomenon,” but a symptom of increasing pollutant emissions due to human activity.
This forecast comes a day after the release of a study concluding that climate change caused by human activity has increased the risk of heatwaves like the one that fueled the wildfires in Portugal and Spain by 40 times in August.
