'Nobody is safe': The world has endured its 'hottest 12 months on record'

Temperatures on Earth in the past 12 months were the hottest ever recorded, with everybody experiencing "unusual climate-driven heat", an analysis has found.

Last month was the world's hottest October on record by a massive margin. Source: AAP / Joel Carrett

KEY POINTS

• Earth has had its hottest 12 months on record, according to a new analysis.
• It found that 90 per cent of humanity endured at least 10 days of high temperatures.
• The average global temperature was 1.3C higher than the pre-industrial climate.

The past 12 months on Earth were the hottest ever recorded, according to a report by Climate Central, a US-based non-profit science research group.

The peer-reviewed report says burning petrol, coal, natural gas and other fossil fuels that release planet-warming gases such as carbon dioxide, and other human activities, caused the unnatural warming from November 2022 to October 2023.

During the course of the year, 7.3 billion people, or 90 per cent of humanity, endured at least 10 days of high temperatures that were made at least three times more likely because of climate change.

"People know that things are weird, but they don't they don't necessarily know why it's weird. They don't connect back to the fact that we're still burning coal, oil and natural gas," said Andrew Pershing, a climate scientist at Climate Central.

"I think the thing that really came screaming out of the data this year was nobody is safe. Everybody was experiencing unusual climate-driven heat at some point during the year."

The average global temperature was 1.3C higher than the pre-industrial climate, which scientists say is close to the limit countries agreed not to go over in the Paris Agreement - a 1.5C rise.

The impacts were apparent as one in four humans, or 1.9 billion people, suffered from dangerous heatwaves.

At this point, said Jason Smerdon, a climate scientist at Columbia University in the US, no one should be caught off guard.

"It's like being on an escalator and being surprised that you're going up," he said.

"We know that things are getting warmer, this has been predicted for decades."

The heat of the last year, intense as it was, is tempered because the oceans have been absorbing the majority of the excess heat related to climate change, but they are reaching their limit, said Kim Cobb, a climate scientist at Brown University.

"Oceans are really the thermostat of our planet ... they are tied to our economy, food sources and coastal infrastructure."`

One in four humans, or 1.9 billion people, suffered from dangerous heatwaves in the past year. Source: Getty / Pablo Blazquez Dominguez

On Wednesday, European Union scientists said this year is set to be the world's warmest in 125,000 years, after data showed last month was the hottest October on record by a massive margin.

Last month exceeded the previous highest October average temperature, from 2019, by 0.4C, the EU's Copernicus Climate Change Service (C3S) Deputy Director Samantha Burgess said, describing the temperature anomaly as "very extreme".

That has made 2023 as a whole "virtually certain" to be the warmest year recorded, C3S said in a statement.

The heat is a result of continued greenhouse gas emissions from the burning of fossil fuels, combined with the emergence this year of the naturally occurring El Niño climate pattern, which warms the surface waters in the eastern Pacific Ocean.

The current hottest year on record is 2016 — another El Niño year — although 2023 is on course to overtake that.

Copernicus' dataset goes back to 1940. "When we combine our data with the IPCC, then we can say that this is the warmest year for the last 125,000 years," Burgess said.

The longer-term data from the United Nations climate science panel IPCC includes readings from sources such as ice cores, tree rings and coral deposits.