The past three years were the world’s hottest on record

1 month ago 14

2025 was officially the planet’s third-warmest year on record behind 2024 and 2023, and positive feedback loops are already accelerating global heating faster than predicted.

The world is on track to overshoot the Paris Agreement target to limit warming to 1.5 to 2 degrees above the pre-industrial average, scientists say, meaning societies must prepare for climate adaptation and should plan how to remove greenhouse gases already in the atmosphere.

The past three years have been the hottest years on record globally.

Last year’s average global surface air temperature was 14.97 degrees, only 0.01 degrees cooler than 2023 and 0.13 degrees cooler than 2024, the European Centre for Medium-Range Weather Forecasts (ECMWF) reported on Thursday. Air temperature above global land areas was second warmest, while global sea surface temperature was third warmest.

“That means that the last three years have been the hottest on record, regardless of the order,” said Professor Sarah Perkins-Kirkpatrick, a climate scientist at Australian National University. “As a globe, when you average out all of the [regional] variability, the signal is very, very strong, and it’s just getting stronger almost year on year.”

The hottest year on record on both land and sea was 2024, and the past 11 years have been the 11 warmest on record. Temperatures for 2023-25 averaged more than 1.5 degrees above the pre-industrial level – exceeding the goal set by the 2015 Paris Agreement over a three-year period for the first time, though the trend would need a decade of data to be considered permanent.

Professor Ian Lowe, a climate scientist at Griffith University, said it was no longer possible to meet the 1.5-degree goal, while 2 degrees also looked increasingly unlikely.

“It’s getting harder and harder to be optimistic,” Lowe said. “The depressing thing is that world emissions are still increasing, which means an observer from another galaxy would say that we know what’s causing climate change, but we’re not doing anything about it as a global civilisation.

“Locally, while we’re facing the bushfires in Victoria and the floods in Queensland and the more frequent extreme events that have been predicted by the science since the 1980s, we are still approving extensions of coal mines and still approving new gas fields as if we didn’t know what was causing the problem.”

The Intergovernmental Panel on Climate Change warns that 2 degrees of global warming would make extreme heat 2.6 times worse, raise sea levels by 6 centimetres, accelerate extinctions, reduce crop yields and global fisheries, and increase extreme weather events.

Lowe said climate models could not account for positive feedback loops, such as forests being more likely to burn and thereby release more carbon dioxide, polar ice caps shrinking so the dark water absorbs more sunlight and heats up, and the Arctic tundra melting and releasing methane, all of which were happening.

“That’s probably why we are now seeing in the mid-2020s the sort of changes that climate models were suggesting we would see sometime towards the late 2030s,” Lowe said.

In February 2025, the combined sea ice cover from both poles fell to its lowest value since at least the start of satellite observations in the late 1970s, the ECMWF figures show. Antarctica saw its warmest annual air temperature on record and the Arctic its second warmest.

Perkins-Kirkpatrick said Australia needed to have a serious conversation about climate adaptation because some warming – “definitely 1.5, extremely likely to 2.0, and very likely higher” – was baked in.

The sooner countries reached net zero – where the amount of greenhouse gases entering the atmosphere is balanced by the amount removed – the less severe the climate change would be, she said. It might also be possible to go further and achieve “net negative” by using technology and reforestation to reduce the build-up of carbon dioxide in the atmosphere.

“It’s imperative we reach net zero – I can’t stress that enough – but we’re now well and truly past the point where that’s no longer enough,” Perkins-Kirkpatrick said.

“Net negative is imperative if we want to maybe overshoot 1.5 degrees and then come back down to a lower global average temperature – there’s talk of that, but whether or not it’s feasible, that’s the problem.”

ECMWF operates the Copernicus Climate Change Service and Copernicus Atmosphere Monitoring Service for the European Commission. The results encompass global climate monitoring from other organisations including NASA, NOAA, the UK Met Office, Berkeley Earth, and the World Meteorological Organisation.

Australia’s fourth-warmest year on record was 2025 at 1.23 degrees above the 1961-90 average, behind 2019, 2024 and 2013, separate figures from the Bureau of Meteorology show.

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