The UK should be prepared to cope with weather extremes as a result of at least 2 °C of global warming by 2050, independent climate advisers have said.

The country was "not yet adapted" to worsening weather extremes already occurring at current levels of warming, "let alone" what was expected to come, the Climate Change Committee (CCC) wrote in a letter addressed to the government.

The committee said they would advise that the UK prepare for climate change beyond the long-term temperature goal set out in the Paris Agreement.

The letter came as the World Meteorological Organisation (WMO) confirmed that 2024 had seen a record rise of carbon dioxide (CO2) in the atmosphere.

CO2 is the gas mainly responsible for human-caused climate change and is released when fossil fuels are burnt, as well as in other activities.

The CCC's letter came after it had been asked to provide advice on a timeframe for setting adaption scenarios, based on "minimum climate scenarios".

They urged the government to set out a framework of "clear long-term objectives" to prevent further temperature rise, with new targets every five years and departments "clearly accountable" for delivering those goals.

The CCC said they would be able to provide further details on potential "trade-offs" in May 2026, when they will release a major report outlining how the UK can adapt to climate change.

The committee released their last report in April this year, which said preparations in the UK for rising temperatures were "either too slow, has stalled, or [are] heading in the wrong direction".

It warned that this lack of progress could leave the UK vulnerable to serious economic and health impacts in the decades ahead, from hospitals and care homes to food and water supplies.

And it said that the impacts of high temperatures were already apparent, for example, in schools.

The CCC cited preliminary findings from the Department for Education, which reported there were, on average 1.7 days of "extreme overheating", as well as lost learning time due to heat.

UK 'not keeping up' with increasing climate risks

The Paris Agreement was signed in 2015, and saw almost 200 countries pledge to try and prevent global temperatures from rising more than 1.5 °C above pre-industrial levels, and to keep "well below" 2C.

As the CCC outlined in their letter, a global warming level of 2 °C would have a significant impact on the UK's weather, with extreme events becoming more frequent and widespread.

They said the UK could expect increased heatwaves, drought and flooding, and wildfire season would likely extend into autumn.

Baroness Brown, chairwoman of the adaptation committee for the CCC, said: "People in the UK are already experiencing the impacts of a changing climate, and we owe it to them to prepare, and also to help them prepare.

"Adaptation in the UK is not keeping up with the increase in climate risk. The impacts on the UK are getting worse and [the government] needs more ambition," she told the BBC's Today programme.

The chairwoman also levelled criticism at Conservative leader Kemi Badenoch, who pledged to scrap the UK's landmark climate change legislation and replace it with a strategy for "cheap and reliable" energy.

Baroness Brown dubbed the promise "disappointing", and said she hoped that the Conservative leader would "reflect on the fact that the act covers both adaptation and mitigation".

The UK is already experiencing shifting weather patterns due to climate change, with four official heatwaves confirmed in 2025 across what the Met Office have said was the hottest summer on record.

Met Office climate scientists have found that a summer as hot or hotter than 2025 is now 70 times more likely than it would have been in a "natural" climate, with no human-induced greenhouse gas emissions.

Record rise in CO2

The increase of CO2 in the atmosphere between 2023 and 2024 was the largest since modern measurements started in the late 1950s, the WMO said.

This follows findings first reported by the Met Office in January.

"The heat trapped by CO2 and other greenhouse gases is turbo-charging our climate and leading to more extreme weather," said WMO Deputy Secretary-General Ko Barrett.

"Reducing emissions is therefore essential not just for our climate but also for our economic security and community well-being," she added.

The UN's Intergovernmental Panel on Climate Change has previously said CO2 levels are at their highest in at least two million years, based on longer-term records like marine sediments and ice cores.