The UK could reach its highest temperature on record today or tomorrow, surpassing the current record of 38.7C (101F) set in Cambridge in 2019.
The mercury can soar above 38°C (100°F), 39°C (102°F) or even 40°C (104°F) in parts of the country, with the current heat wave expected to peak on Tuesday, before cooler conditions arrive from the Atlantic, rather than hot weather coming from southern Europe.
The Met Office has issued its first red warning for extreme heat, covering part of England from London to Manchester and York, and weather experts have said high temperatures could put lives at risk.
In addition, the UK Health Safety Agency has raised its health heat warning from level three to level four – a ‘national emergency’.
Level four is reached “when a heat wave is so severe and/or prolonged that its effects extend outside the health and social care system…At this level, illness and death can occur among healthy people, not just in high-risk groups (such as the elderly)”.
Scientists say climate change is increasing the likelihood of exceptional heat waves in Britain, a country unaccustomed to such high temperatures.
So how much are these extreme heat waves due to climate change?
Alex Deakin of the Met Office is no doubt.
The meteorologist told Sky News: “We’ve had heat waves in the past. But what’s absolutely clear is that these heat waves, these heat waves are getting more intense, more frequent. The science is absolutely clear that climate change has its footprints all over this current heat wave.”
He added: “What we do know is that 40C is now 10 times more likely in the UK than it would be under a naturally variable climate – so a climate that humans have not influenced.
“So we are going to experience these kinds of heat waves more and more frequently.”
He continued: “The heat waves are getting more severe, fiercer, they last longer and the temperatures are rising and it’s all part of climate change.”
Jim Dale, senior meteorologist at British Weather Services, said the UK is at a “crossroads” in terms of “the most indisputable sign of change we have ever seen”.
“The data has been one-sided over the last decade and more. The world records have all been set over the last decade in terms of heat and CO2 levels.
“It’s not denial anymore – man-made climate change – it’s here.”
He added: “It’s not just about heat. It’s also about other aspects that we will see in the future – storms, floods – these aspects that climate change brings.”
How prepared is the UK for such high temperatures?
Mr Deakin said the infrastructure in the UK is not ready for such levels but increasingly needs to be prepared for it, including by government.
He called them “unprecedented values”, adding: “When you go on vacation, your body is prepared for it and the infrastructure in those countries (like southern Europe) is in place. You have air conditioning.”
Mr Deakin warned: “It’s the nighttime temperatures, as well as the daytime temperatures, that are going to cause problems (in the UK) because people won’t be able to sleep as well, and if your body doesn’t get that rest then it really struggles to cope with the high temperatures.”
What is a national heatwave emergency and what could it mean for the UK?
Schools close, hospitals cancel appointments and events are canceled
Met Office chief executive Penny Endersby said people may find it hard to know what to expect when “climate change has brought such unprecedented severe weather events”.
“Here in the UK we are used to treating a hot spell as a chance to go play in the sun,” she added.
“It’s not that kind of weather.”
What should the UK do?
Nigel Arnell, professor of climate system science at the University of Reading, said Britain needed to prepare for warmer weather in the future, by retrofitting buildings to cope with extreme weather and planting more greenery in cities.
Adaptation and resilience must become a political priority, he said.
“We cannot continue to deal with the extremes in crisis mode,” Mr. Arnell said.
Susan Scholefield – a former director of the Cabinet Office’s Civil Contingencies Secretariat – said people should make their homes more fuel efficient.
In the immediate situation, she said people should adapt their behavior.
“Close the curtains during the day and open them at night,” she suggested.
London Mayor Sadiq Khan has urged Londoners to only travel on Mondays and Tuesdays if essential and to prepare for disruption as speed restrictions will be in place on the rail and tube networks.
And firefighters including the South Wales Fire And Rescue Service, Scottish Fire And Rescue and London Fire Brigade have issued safety warnings, urging people to act responsibly.
They warn people to dispose of barbecues, lit cigarettes and glass bottles responsibly, not to burn rubbish such as garden waste and to use local authority services instead.
And that barbecues should not be used on balconies or near sheds, fences, trees, shrubs and yard waste to prevent anything from igniting.
They also urge people who cool off in streams to be aware of cold water shock.
What is the evidence from the Met Office linking climate change and heatwaves in the UK?
The Met Office has rated 2018 as the hottest summer on record.
He found that the probability of such a hot summer in a natural climate was only 0.5%. But because of greenhouse gases in the atmosphere, that figure had dropped to 12%.
In other words, a record summer is almost 30 times more likely today due to climate change.
The warming trend will accelerate. Mid-century, the Met Office predicts that a summer as hot as 2018 will happen every two years.
And if greenhouse gas emissions continue to rise as predicted, by the end of the century temperatures in the UK will peak at 40C (104F) or more once every three to four year.
How many heatwave-related deaths are there each year in the UK?
Such sweltering heat is life-threatening – especially for young and old – when temperatures remain high for several days.
Heatwave deaths currently average around 2,000 per year. By 2050, they are expected to reach 7,000.
“Even as a climatologist who studies this stuff, it’s scary,” Professor Hannah Cloke, a natural hazards researcher at the University of Reading, said of the current situation.
“It seems real. At the beginning of the week, I was worried that my goldfish would get too hot. Now, I’m worried about the survival of my family and neighbors.”
What will weather experts learn from this latest heat wave?
Kirsty McCabe, producer of Sky Weather, said scientists are waiting until after the event, once we see how hot it was, before they can attribute it to climate change.
She said: “They compare the temperatures we would expect under different scenarios (i.e. different amounts of carbon dioxide in the atmosphere). With extreme temperatures linked to higher emissions.”
She added: “Current research indicates that heat waves will occur more frequently, last longer and be more intense unless we curb global warming. Otherwise 40C in the UK could occur every few minutes. years in the future.”
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