Overview
- The report calculates an average 546,000 heat-related deaths a year in 2012–2021, marking a 23% increase from the 1990s.
- Smoke and pollution tolls are surging, with wildfire smoke linked to a record 154,000 deaths in 2024 and fossil-fuel air pollution killing about 2.5 million annually.
- Extreme heat drove record labor impacts in 2024 with 639 billion work hours lost and an economic cost exceeding $1 trillion, as least developed nations saw losses near 6% of GDP.
- Public and private finance sustained fossil expansion, including $956 billion in government subsidies in 2023, $611 billion in bank lending in 2024, and production plans far beyond 1.5°C pathways.
- Produced by 128 experts led by UCL with WHO collaboration, the 2025 assessment urges rapid deployment of renewables, accelerated adaptation, and stronger health-system preparedness ahead of COP30.