Last month was the hottest October on record globally, Europe's climate monitor said on Wednesday, as months of exceptional heat are likely to make 2023 the warmest year in history.

With temperatures soaring beyond previous averages by exceptional margins, scientists say the pressure on world leaders to curb planet-heating greenhouse gas pollution has never been more urgent as they prepare to meet in Dubai for the Cop28 climate conference this month.

October was 1.7C warmer than an estimate of the October average for the preindustrial era, said the EU's Copernicus Climate Change Service (C3S).

And global average temperatures since January have been the highest in records going back to 1940, the monitor added, registering 1.43C above the 1850-1900 pre-industrial average.

Beyond these official records, scientists say proxy data for the climate going back further – like tree rings or ice cores – suggests the temperatures seen this year could be unprecedented in human history, potentially the warmest in more than 100,000 years.

In October, drought parched parts of the United States and Mexico, while huge swathes of the planet saw wetter than normal conditions often linked to storms and cyclones.

Sea surface temperatures were the highest ever recorded for the month, a phenomenon driven by global warming that scientists say plays a key role in driving storms to be more ferocious and destructive.

"October 2023 has seen exceptional temperature anomalies, following on from four months of global temperature records being obliterated," said Samantha Burgess, C3S Deputy Director.

"We can say with near certainty that 2023 will be the warmest year on record, and is currently 1.43 degrees Celsius above the preindustrial average. The sense of urgency for ambitious climate action going into Cop28 has never been higher."

The landmark Paris Agreement saw nearly 200 countries pledge to limit global warming to well below two degrees Celsius since the pre-industrial era and preferably a safer 1.5C. (AFP)