Overview
- Global mean temperature from January to August 2025 was about 1.42°C above the pre‑industrial average, putting the year on pace to rank second or third warmest on record.
- The period 2015–2025 constitutes the 11 warmest years in the 176‑year record, with 2023, 2024 and 2025 identified as the three hottest years.
- Concentrations of heat‑trapping gases hit new highs in 2024 and continued rising in 2025, while ocean heat content set records and increased further this year.
- Observed impacts include roughly 450 gigatonnes of glacier ice lost in 2024, record‑low Arctic post‑winter sea ice, persistently depressed Antarctic sea ice, and a continuing long‑term rise in sea level.
- The update lands ahead of COP30 in Belém, where attendance by top leaders is reduced, as UN chief António Guterres urges urgent action to minimize and shorten any overshoot after global emissions rose 2.3% in 2024.