2023 virtually certain to be hottest year humans have ever experienced, scientists say

Louise Boyle and Stuti Mishra
Updated ·2 min read

2023 is virtually certain to be the hottest year on record – an ominous milestone just weeks from the global Cop28 UN summit where the need to speed up the fight against the climate crisis becomes more urgent by the day.

Scientists on Tuesday confirmed what most have said was likely in the wake of record-breaking spring and summer temperatures around the world. October 2023 was also the warmest October on record globally.

"We can say with near certainty that 2023 will be the warmest year on record, and is currently 1.43C above the preindustrial average," said Samantha Burgess, deputy director of the EU’s Copernicus Climate Change Service, who made the announcement.

"The sense of urgency for ambitious climate action going into Cop28 has never been higher."

Copernicus also found that:

  • October marked the sixth consecutive month that Antarctic sea ice was at record lows for the time of year – 11 per cent below average

  • Sea surface temperatures hit an average of 20.79C, the highest on record for October

  • Europe saw above-average rainfall in October, notably in Storm Babet which hit northern Europe, and storm Aline impacting Portugal and Spain, bringing heavy downpours and flooding

  • It was also wetter than average in several regions including the US southwest, parts of the Arabian Peninsula, regions of Central Asia and Siberia, southeast China, Brazil, New Zealand and regions of southern Africa. These conditions were often linked to powerful cyclones which triggered heavy rainfall and substantial damage

  • It was drier than average in the US south and parts of Mexico leading to severe drought, along with central and easternmost Asia, and Australia

The Copernicus Climate Change Service (C3S), the EU forecasting and climate agency, based its findings on billions of measurements from satellites, ships, aircraft and weather stations around the world.

Scientists offered blunt responses to the findings.

“Laid out so starkly, the 2023 numbers on air temperatures, sea temperatures, sea ice and the rest look like something out of a Hollywood movie,” said David Reay, executive director of the Edinburgh Climate Change Institute, University of Edinburgh.

"Indeed, if our current global efforts to tackle climate change were a film it would be called 'Hot Mess'.”

This summer has already been declared the hottest on record in the northern hemisphere by WMO and Nasa, and winter temperatures in South America and Australia have also been shattering records.

The high temperatures are largely driven by greenhouse gas emissions released from burning fossil fuels, which trap the heat on the Earth’s surface.

Temperatures are also being amplified this year by the emergence of a natural climatic pattern El Nino.