This year ‘certain’ to be hottest in history, with October breaking monthly heat record

This year is “virtually certain” to be the hottest in 125,000 years, as October broke global monthly heat records for the fifth time this year.

Last month smashed the previous record set in 2019 by 0.4 degrees, data released by the Copernicus Climate Change Service found.

October marked the fifth time this year that the Earth broke heat records.Credit: Brook Mitchell

“When we combine our data with the Intergovernmental Panel on Climate Change, then we can say that this is the warmest year for the last 125,000 years,” Samantha Burgess, deputy director of the Copernicus Climate Change Service told Reuters.

An agency statement added that this meant 2023 was “virtually certain” to be the hottest on record.

Meanwhile, the average surface air temperature was 15.3 degrees, 0.85 degrees above the 1991-2020 average for October.

The first 10 months of this year have recorded the highest global mean temperature at 1.43 degrees above the 1850-1900 pre-industrial average, and 0.1 degree hotter than the 10-month average for 2016 – the warmest year on record.

That year, the Great Barrier Reef experienced some of its worst coral bleaching as global temperatures soared during an El Nino event, which makes the weather hotter and drier.

The data comes just weeks before COP28, the annual United Nations climate meeting, where governments will discuss how to limit and prepare for future climate change as well as what progress has been made to reduce emissions since the 2015 Paris Agreement.

Already this year June, July, August and September have been the hottest-ever consecutive months globally.

Melbourne University climate scientist Dr Andrew King said while El Nino was contributing to the heat, it didn’t explain the massive temperature anomalies.

“Human-caused climate change, due to our ongoing high greenhouse gas emissions, is the main reason we’re seeing record high global temperatures,” he said.

“For Australia, October was dry but not especially hot. With the continuing El Nino we should be prepared for drought development and a higher chance of extreme heat events in the coming months.”

“This might seem like an unusually hot year, but in 10 or 20 years this won’t seem that unusual which is a scary thought. This is what is expected with global warming.”

Monash University associate professor in the School of Earth, Atmosphere and Environment Dr Ailie Gallant

Monash University associate professor in the School of Earth, Atmosphere and Environment Dr Ailie Gallant described the data as “mind-boggling”, and warned that warming would continue without aggressive action to limit greenhouse gases.

“[The figures] are just insane,” she said. “This is something as climate scientists we look at our computer screens and think, ‘yes this will happen one day’. But that day is now.”

“This might seem like an unusually hot year, but in 10 or 20 years this won’t seem that unusual which is a scary thought. This is what is expected with global warming.”

“There is only one solution here: we need to lower emissions to slow this down and move completely away from fossil fuels - that is the only hope we have of reversing it in the coming decades.”

Emeritus Professor Ian Lowe, from Griffith University, the former president of the Australian Conservation Foundation, said he had warned about climate change for the last 35 years and was disappointed by the lack of mitigation measures that have been implemented.

“The Paris Agreement recognised that global emissions would need to peak by 2020 to avoid dangerous climate change, but emissions are still increasing,” he said. “While Australian people have voted with their wallets and embraced solar electricity, we still don’t have policies to clean up our transport, agriculture and industry.”

“Given what the climate data are showing, it is criminally irresponsible to be allowing and in some cases even promoting new fossil fuel projects such as gas fields. Rather than squandering hundreds of billions on nuclear submarines, we should be investing urgently in mitigation and measures to allow us to adapt to changes we cannot prevent.”

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