Overview
- UN and WMO assessments say 2025 is likely to finish as the second or third warmest year, making 2023–2025 the three hottest in the 176‑year record.
- Global temperatures from January to August 2025 averaged about 1.42°C above the 1850–1900 baseline, with a shift toward neutral or La Niña conditions easing but not reversing the heat.
- WMO chief Celeste Saulo says staying within 1.5°C in the near term will be virtually impossible without a temporary overshoot, though returning below that level later remains possible.
- CO2 concentrations jumped by a record amount in 2024 to a new high, and the hydrological year to October 2024 saw about 450 billion tonnes of glacier ice lost, pushing sea levels higher.
- The UN reports growth in multi-hazard early-warning systems since 2015, yet 40% of countries still lack them, and UNEP estimates a US Paris withdrawal would add roughly 0.1°C to future warming.