Copernicus: October 2026 was the warmest October on record, and 2026 is likely the second-warmest year

A record-hot October

The Copernicus Climate Change Service, the climate arm of the European Union's Earth observation programme, announced on Friday, 6 November, that October 2026 was the warmest October ever recorded worldwide. Average global air temperature at the surface was 1.75°C above the 1850-1900 pre-industrial baseline. It was the third consecutive month to exceed the 1.5°C threshold set by the Paris Agreement. Sea surface temperatures outside the polar regions averaged 20.95°C, a record for October that beat the previous high set in October 2023.

What 2026 is likely to look like

Copernicus considers it likely that 2026 will be the second-warmest calendar year on record, behind 2024. The service puts the chance that 2026 matches or exceeds 2024 at 20%. It also calls it almost certain that 2026 will average at least 1.5°C above pre-industrial levels, which would make it the second year after 2024 to do so. The Paris goal refers to a long-term average over many years, so a single warm year does not formally breach it. The average for 2023 to 2026 is also expected to exceed 1.5°C. Independent analyses by Berkeley Earth and Carbon Brief, which use different datasets and methods, had already reached similar conclusions. Scientists cited in the coverage consider a temporary overshoot of the limit unavoidable and say it could occur as early as 2030.

2026-081.65

2026-091.63

2026-101.75

2026-08

1.65 °C

2026-09

1.63 °C

2026-10

1.75 °C

Data from the article text

The summer and early autumn months

August 2026 tied with July 2023 as the warmest month ever recorded, with an average global temperature of 16.96°C, or 1.65°C above the pre-industrial estimate. September 2026 was the second-warmest September on record, at 16.27°C. That was 0.82°C above the 1991-2020 average and 1.63°C above the 1850-1900 baseline. September was also the second consecutive month of 2026 above 1.5°C. The last time two consecutive months ran above that level was October and November 2025. Copernicus says the pattern shows extreme heat is appearing more frequently rather than in isolated episodes.

El Niño drives the heat

The El Niño pattern is strengthening across the tropical Pacific, where Copernicus recorded a sea surface temperature anomaly of 3.21°C for October, described as a historically high level. Copernicus said this exceeded high values recorded in earlier very strong El Niño events. On 21 October, the United Nations warned that the current El Niño, a natural phenomenon that raises global temperatures, could be without precedent. Coverage of the Copernicus release says the effects of the phenomenon are expected to become more noticeable in 2027.

Backdrop to the climate talks

The bulletin was published just before the UN climate conference COP31, which starts on Monday, 9 November, in Turkey and runs for two weeks. Reports ahead of the conference list the events of this year as deadly floods in Nepal, intense heatwaves in Europe and extensive forest fires in Indonesia. Coverage links those events to the growing impacts of climate change.