The world just experienced its warmest January on record, marking the first 12-month period in which temperatures averaged more than 1.5 degrees Celsius above preindustrial times, the European Union's climate change monitoring service said on Thursday.
Already 2023 was the planet's hottest year in global records going back to 1850, as human-caused climate change and El Nino, the weather pattern that warms the surface waters in the eastern Pacific Ocean, pushed temperatures higher.
"It is a significant milestone to see the global mean temperature for a 12-month period exceed 1.5 C above preindustrial temperatures for the first time," said Matt Patterson, an atmospheric physicist at the University of Oxford.
The previous warmest January was in 2020, according to the Copernicus Climate Change Service (C3S) records, which go back to 1950.
Countries agreed at United Nations climate talks in Paris in 2015 to keep global warming well below 2 C and aim to limit it to 1.5 C, a level regarded as crucial to preventing the most severe consequences.
The first 12-month period of exceeding 1.5 C does not yet mean the Paris goal has been missed, as the U.N. agreement refers to an average global temperature over decades.
Some scientists, however, have said the 1.5 C aim can no longer realistically be met, and have urged governments to act faster to cut carbon dioxide emissions to limit the amount of overshoot of the target.
"Rapid reductions in greenhouse gas emissions are the only way to stop global temperatures increasing," C3S deputy director Samantha Burgess said.
At the same time, economic weakness and political pressures are challenging government will to implement policies to curb greenhouse gases as politicians strive for re-election in a bumper year for democratic elections.
"We are heading towards a catastrophe if we don't fundamentally change the way we produce and consume energy within a few years," said Denmark's Global Climate Policy Minister Dan Jorgensen. "We don't have long," he said.
Every month since June 2023 has been the world's hottest on record, compared with the corresponding month in previous years.
U.S. scientists have said 2024 has a one-in-three chance of being even hotter than last year, and a 99% chance of ranking in the top five warmest years.
El Nino began to weaken last month, and scientists have indicated it could shift to the cooler La Nina counterpart later this year. Still, average global sea surface temperatures last month were the highest for any January on record.
While it is winter in the northern hemisphere, in parts of South America, experiencing the southern hemisphere summer, temperatures are blistering.
Argentina endured a heatwave between Jan. 21 and 31, while the Chilean capital of Santiago registered its third hottest temperature on record on Jan. 31, climbing above 37 C.
Such heat in central Chile caused wildfires that killed at least 131 people in early February.