1376. Copernicus: 2025 on Track to be the Third-Warmest October on Record

According to the Copernicus Climate Change Service (C3S), October 2025 will be the third-warmest October on record globally, with an average surface temperature of 15.14°C, 1.55°C higher than the estimated pre-industrial average from 1850 to 1900. It will be the first time since April 2025 that the temperature has exceeded 1.50°C. 2025 is almost certain to be either the second or third warmest year on record.

While the annual average temperature in 2025 may not exceed 1.5°C, the past three years have been exceptionally warm, making it likely that the average temperature from 2023 to 2025 will exceed 1.5°C, and some have suggested that we are entering a decade where the 1.5°C limit is likely to be exceeded.

The average sea surface temperature (SST) between 60°S and 60°N in October 2025 was 20.54°C, the third-warmest on record for that month. Much of the North Pacific continued to record significantly above-average SSTs, with the western portion experiencing record-high temperatures. Meanwhile, temperatures in the central and eastern equatorial Pacific remained near or below the 1991-2020 average, reflecting a transition from ENSO-neutral to a weak La Niña event.

Contributor: Miyuki IIYAMA, Information Program