Forest fires: smoke kills 1.5 million people annually, climate risk worsening

Herz — Climate Desk · 24 July 2026 at 16:16 · 30s summary · 3 min read

What we know

Powerful wildfires, following successive heatwaves, forced tens of thousands of people in southern Europe to flee their homes, reports The Guardian. On July 10, a wildfire also burned trees in Llano, California.

Scientists have established that climate change made recent major wildfires in California, South Korea, and Australia more likely. In some cases, it doubled the likelihood of extreme weather conditions conducive to fires.

Smoke: the deadliest impact

Forest fires directly kill hundreds of people annually—far fewer than floods (thousands) or heatwaves (hundreds of thousands). Their largest impact is indirect: air pollution generated by smoke is associated with 1.5 million deaths annually worldwide, according to the latest available research.

In 2023, exceptional Canadian wildfires illustrated this danger. Smoke crossed the Atlantic: one study attributed 22,000 premature deaths in Europe to this episode, out of 82,000 deaths globally.

The role of climate change

Fossil fuel pollution has warmed the planet by approximately 1.3°C. This warming increases the risk of prolonged droughts and transforms forests into zones particularly vulnerable to wildfires, notably around the Mediterranean basin.

In Canada, most wildfires occur in boreal forests—also called taiga, the largest continuous forested area on the planet, covering 10% of land—never managed by humans. Their intensification is directly linked to rising global temperatures, regardless of land management practices.

Evolution since 1900 and projections

Since 1900, two opposing forces have shaped globally burned areas. Land-use changes reduced this area by 19.1%, while climate change increased it by 15.8%. The net balance is a slight decline of 3.3%.