Last year was the world’s third warmest on record, underscoring a trend already fuelling destructive fires and floods in Australia in the early days of 2026.
Official confirmation from respected climate monitoring outfit Copernicus puts 2025 marginally behind 2023 and 0.13C cooler than 2024, which hangs on as the hottest year on record.
In 2025, the global surface air temperature was 1.47C above the pre-industrial level, with temperatures now averaging above 1.5C – the agreed limit set by signatories of the Paris Agreement – for three years running.
The global climate pact has not yet been exceeded as it relies on longer-running trends.
But if warming continues as expected, the 1.5C benchmark could be reached by the 2030s – more than a decade earlier than first predicted when the landmark pact was signed.
In Australia, 2025 was tarnished by record-high ocean temperatures, driving widespread coral bleaching off the Western Australian coast and in the Great Barrier Reef.
Elevated ocean temperatures were also thought to have contributed to the intensity and rainfall extremes brought by ex-tropical cyclone Alfred as it barrelled through southeast Queensland and northern NSW.
Griffith University Emeritus professor of science, technology and society Ian Lowe said that since the 1980s, scientists had been warning of both increases in average temperatures as well as more frequent and severe extreme weather events.
“At the moment, we’re seeing appalling bushfires in Victoria and appalling flooding in Queensland,” he told AAP.
“And this is exactly what the science has been telling us.”
Australians had already been warned of a catastrophic summer of fires and another year of warmer ocean temperature could also spell trouble for coral reefs and the tourism businesses reliant on them.
“It’s getting more and more unlikely that the Great Barrier Reef can recover from the succession of bleaching events,” Prof Lowe said.
Globally, the past three years have been exceptionally warm for a few main reasons, the first being the ongoing accumulation of greenhouse gases in the atmosphere trapping in heat.
Carbon sinks, ecosystems that soak up carbon, have also been weakening.
As well, sea-surface temperatures have been particularly high, in part due to an El Nino event but also other climate change-influenced variability.
Changes in aerosol concentrations has also contributed to the three-year run of particularly elevated global temperatures.
A neutral to weak La Nina – a weather pattern associated with cooler global temperatures – in the equatorial Pacific contributed to lower air and sea temperatures in the tropics last year than in 2024 and 2023.
The higher temperatures of the two years prior were in part driven by a strong El Nino event, linked to warmer global temperatures.
Cooler temperatures in some regions were countered somewhat by a warmer polar region, with Antarctica experiencing its highest annual average temperature value, and second-highest in the Arctic.
In early 2025, sea ice across the two poles was at its lowest level since satellite monitoring began in the 1970s.
Prof Lowe was critical of Australia’s commitment to slowing global temperate rise.
“At the state and national level, governments are still behaving as if we can keep approving extensions of coal mines and new new gas field project, which is literally tipping petrol on the fire.”
Copyright @ AAP 2026
