BRUSSELS - This year is virtually certain to rank among the three warmest on record, with October 2025 being the third-warmest October globally, according to data released Thursday by the EU's Copernicus Climate Change Service (C3S).

The average global surface air temperature in October was 15.14 degrees Celsius, 0.70 degrees above the 1991-2020 average and 1.55 degrees above the pre-industrial level (1850-1900). It was 0.16 degrees cooler than the record October in 2023 and 0.11 degrees cooler than October 2024, the data showed.

The 12-month average from November 2024 to October 2025 stood 1.50 degrees above pre-industrial levels, continuing an extended spell of exceptional warmth.

C3S said that 2025 is almost certain to end as the second- or third-warmest year since records began, possibly tied with 2023 and just behind 2024, the hottest year on record.

"While 2025 may not be the hottest year, it is almost certain to rank in the top three. The last three years saw exceptional temperatures, and the average for 2023-2025 is likely to exceed 1.5 degrees Celsius, the first time for a three-year period," said Samantha Burgess, Strategic Lead for Climate at C3S.

October's global sea surface temperatures remained close to record highs, averaging 20.54 degrees Celsius over latitudes from 60 degrees north to 60 degrees south, the third-highest on record.

The North Pacific recorded extreme warmth, while cooler conditions appeared in the central and eastern equatorial Pacific, indicating a transition toward weak La Nina conditions, according to C3S.

In the Arctic, sea ice extent was 12 percent below average, ranking eighth lowest for October, while Antarctic sea ice recorded its third-lowest October extent, 6 percent below average, the data showed.