Analysis from the EU’s Copernicus Climate Change Service says it is now “virtually certain” that 2024 will top all previous hottest periods in the record books.
“After 10 months of 2024, it is now virtually certain that 2024 will be the warmest year on record and the first year of more than 1.5C above pre-industrial levels,” the service’s director general Samantha Burgess said. “This marks a new milestone in global temperature records.”
Each month from January to August this year had already broken monthly records, and this was followed by the second-warmest September and October on record.
“The average temperature anomaly for the rest of 2024 would have to drop to almost zero for 2024 to not be the warmest year,” the analysis says.
The 1.5C threshold is considered the relatively safe level of global average temperature rise, beyond which climate change will accelerate, potentially out of control.
On average, global temperatures this year have been 1.55C above normal. Almost all the world’s countries signed the Paris Agreement in 2015, committing to keep temperature rise to 1.5C or at least as much below 2C as possible.
Already at current levels of temperature rise, extreme weather events have been more frequent and fiercer than scientists expected.
Periods of heatwave in recent years drove temporary breaches of 1.5C, but breaching it continuously for a full calendar year is a significant and worrying development.
Ireland, by contrast, has had one of its cooler years of recent times, but October temperatures were above normal and November has been exceptionally warm so far for the time of year.
Ice-sheet melt is also giving rise to concerns. The Arctic ice sheets have 19pc less ice than normal for this time of year and the Antarctic ice sheets are 8pc smaller than normal.
The latest bulletin comes just days before the start of the Cop29 global climate summit.
Dr Burgess said the continued record-breaking conditions “should serve as a catalyst to raise ambition” on tackling climate change and its causes.
The summit will be overshadowed by the election of Donald Trump as US president, as he previously pulled the US out of global climate agreements, declared climate change a hoax and vowed to accelerate oil and gas production during his term in office.
Observers expressed concern at the impact of a US withdrawal from global climate pacts, with fears it would encourage other nations to water down their commitments.
However, leading climate scientist Dr Friederike Otto, who has led studies all over the world, including in Ireland, said events were outpacing Trump.
“The global move to renewable energy is now happening at an unprecedented pace,” she said. “Nothing the US government can do will change the simple fact that renewable energy is cheaper and more reliable than oil, gas and coal.
