The past 11 years have been the warmest in the modern era, while oceans continue to heat up, too, says the UN weather agency.
The World Meteorological Organization ( WMO ) confirmed on Wednesday that 2025 was one of the three warmest years on record, continuing the streak of extraordinary global temperatures.
After analysing eight international datasets, the organization said that global average surface temperatures last year were 1.44°C above the 1850 to 1900 average.
Two of these datasets ranked 2025 as the second warmest year in the 176-year record, and the other six ranked it as the third warmest year.
Warm despite La Niña
The fact that 2025 was very slightly cooler than the three-year average from 2023 is partly explained by the La Niña phenomenon, which is associated with colder weather.
But WMO insisted that any temporary cooling from La Niña is not reversing the long-term trend of warmer temperatures.
"The year 2025 started and ended with a cooling La Niña and yet it was still one of the warmest years on record globally because of the accumulation of heat-trapping greenhouse gases in our atmosphere," said WMO Secretary-General Celeste Saulo.
The organization added that the high temperatures on land and sea last year helped to fuel extreme weather, including heatwaves, heavy rainfall and deadly tropical cyclones, underlining the need for early warning systems.
Ocean heat
Citing a separate study, WMO highlighted that ocean temperatures were also among the highest on record last year, reflecting the long-term accumulation of heat within the climate system.
Regionally, about 33 per cent of the global ocean area ranked among its historical (1958-2025) top three warmest conditions, while about 57 per cent fell within the top five, including the tropical and South Atlantic Ocean, Mediterranean Sea, North Indian Ocean and Southern Oceans, underscoring the broad ocean warming across basins.
WMO will provide full details of key climate change indicators, including greenhouse gases, surface temperatures, ocean heat and other trends, in its State of the Global Climate 2025 report to be issued in March 2026.
