Copernicus says 2026 is “very likely” to become the second-hottest year on record, with a 20% chance of matching or surpassing 2024, currently the hottest year recorded.¹ The accounts converge on a dual explanation: the El Niño climate pattern is lifting global temperatures on top of longer-term warming caused by human activity.

Both reports point to October as the clearest sign of the pressure on the annual average. Copernicus recorded the planet’s warmest October, with global average air temperature 1.75°C above the pre-industrial benchmark. It was also the third consecutive month above 1.5°C.¹

The ocean figures reinforce the same assessment. Outside the polar regions, average sea-surface temperature reached a record 20.95°C for October, while the tropical Pacific anomaly reached “a historic maximum of 3.21°C,” exceeding peaks seen during earlier very strong El Niño events.² The second account places particular emphasis on that Pacific warmth, arguing that the persistence and intensity of El Niño will determine how much further it pushes the yearly average upward.²

At the same time, the reports draw a distinction between a calendar-year breach and the Paris Agreement’s long-term temperature objective. Copernicus considers it “almost certain” that 2026 will exceed 1.5°C above pre-industrial levels, making it the second calendar year after 2024 to do so.¹ But that does not mean the Paris target has been formally and permanently missed, because the threshold must be exceeded over a much longer period.

The shared conclusion is nevertheless stark: scientists see a temporary crossing of 1.5°C as increasingly likely, potentially before 2030, even as the formal long-term measure remains unresolved.²