That limit is hotter and sooner than most of the previous official advice, and is worse than the 1.5C level most of the world has been trying to stick to.
What is the 1.5C temperature threshold?
Under the 2015 Paris Agreement, countries agreed to try to limit warming to “well below” 2C – and ideally 1.5C.
But with global average temperatures already nearing 1.4C, warnings that we may have blown our chances of staying at 1.5C have been growing.
This new warning from the government’s top advisers, the independent Climate Change Committee (CCC), spells out the risk to the UK in the starkest terms yet.
In a letter today, the CCC said ministers should “at a minimum, prepare the country for the weather extremes that will be experienced if global warming levels reach 2C above pre-industrial levels by 2050”.
It is the first time the committee has recommended such a target, in the hopes of kickstarting efforts to make everything from flooded train tracks to sweltering classrooms more resilient in a hotter world – after years of warnings the country is woefully unprepared.
How climate change affects the UK
The UK is already struggling to cope with the drought, flooding, and heat brought by the current 1.4C – “let alone” what is to come, the advisers said.
Just this year, the country battled the second-worst harvest on record and hottest summer ever, which saw an extra 300 Londoners die.
“Though the change from 1.5C and 2C may sound small, the difference in impacts would be substantial,” CCC adviser Professor Richard Betts told Sky News.
It would mean twice as many people at risk of flooding in some areas, and in southern England, 10 times as many days with a very high risk of wildfires – an emerging risk for Britain.
The experts said the mass building the government is currently pushing, including new nuclear power stations and homes, should even be adaptable for 4C of warming in the future – a level unlikely, but which cannot be ruled out.
Is it too late to stop climate change or limit to 1.5C?
The CCC’s Baroness Brown said in a briefing: “We continue to believe 1.5C is achievable as a long-term goal.
“But clearly the risk it will not be achieved is getting higher, and for risk management we do believe we have to plan for 2C.”
World leaders will discuss their plans to adapt to hotter temperatures at the COP30 climate summit in Brazil in November.
Professor Eric Wolff, who advises the Royal Society, said leaders needed to wake up.
“It is now very challenging even to stay below two degrees,” he told Sky News.
“This is a wake-up call both to continue reducing emissions, but at the same time to prepare our infrastructure and economy for the inevitable climate changes that we are already committed to.”
