The EU’s Copernicus Climate Change Service (C3S) said 2026 is virtually certain to exceed 1.5°C of global warming above pre-industrial levels, becoming the second calendar year to do so after 2024.

The service explained that exceeding the 1.5°C threshold in a single year does not constitute a formal breach of the long-term climate threshold, which is assessed on the basis of sustained average temperatures over a longer period.

Copernicus said 2026 is most likely to become the second-warmest year on record.

It estimated a 20 percent chance that 2026 could tie or exceed the record set in 2024, while forecasts indicate that the average global temperature for the 2023–2026 period will also exceed 1.5°C above pre-industrial levels.

October was the warmest October on record globally, with the average surface air temperature standing 1.75°C above pre-industrial levels.

It was the third consecutive month in which global temperatures exceeded the 1.5°C threshold.