Overview

• The WMO’s latest Air Quality and Climate Bulletin reports that wildfires significantly increased particle pollution in 2024, with the sharpest PM2.5 rise in the Amazon basin and above-average levels in Canada, Siberia and central Africa.
• Officials say wildfire smoke carries a complex mix of pollutants that can degrade air quality far from the flames, with Canadian fires affecting Europe and record 2025 blazes in southern Europe contributing to continent-wide pollution.
• The agency links more frequent, longer fire seasons to climate change and says climate and air-quality challenges must be tackled together, echoing messages from Ko Barrett and scientific officer Lorenzo Labrador.
• The WHO estimates ambient air pollution causes about 4.5 million premature deaths each year, with PM2.5 small enough to penetrate deep into the lungs and cardiovascular system.
• Eastern China recorded continued declines in PM2.5 in 2024 that the WMO attributes to sustained mitigation, underscoring that targeted policies can deliver measurable improvements.