“We are living through climate collapse in real time,” the UN secretary-general, António Guterres, has told COP28 delegates in Dubai.

He spoke at the launch of the World Meteorological Organization’s stark State of the Climate report, which said 2023 will be the hottest year ever recorded.

“This year has seen communities around the world pounded by fires, floods, and searing temperature – and the impact is devastating,” Guterres said. “Record global heating should send shivers down the spines of world leaders. And it should trigger them to act.”

The WMO report, timed to inform the negotiations at COP28, said climate records had been shattered in 2023, leaving “a trail of devastation and despair”.

Data up to the end of October showed 2023 was about 1.4C (2.5F) above pre-industrial levels, driven by the continued rise in carbon emissions from fossil fuel burning and by the return of the El Niño climate pattern. The latter is likely to make 2024 another record year, and bring the internationally agreed limit of 1.5C (2.7F) ever nearer.

“Greenhouse gas levels are record high. Global temperatures are record high. Sea level rise is record high. Antarctic sea ice is record low. It’s a deafening cacophony of broken records,” said the WMO secretary-general, Prof Petteri Taalas.

“These are more than just statistics,” he said. “Extreme weather is destroying lives and livelihoods on a daily basis – underlining the imperative need to ensure that everyone is protected by early warning services. We cannot return to the climate of the 20th century, but we must act now to limit the risks of an increasingly inhospitable climate in this and coming centuries.”