Why is it so hot in UK today? Cause of extreme weather right now explained - is it linked to climate change

Heathrow airport has seen a record weather temperature of 40.2C - well above the 2019 high of 38.7C recorded in Cambridge

The UK is currently being baked by a record-breaking heatwave.

Extreme hot weather has forced the widespread cancellation of train services, while schools have also had to close.

But why are temperatures so hot - and is the current heatwave linked to climate change?

Here’s everything you need to know.

The UK has recorded its highest ever temperature today amid a record heatwave (image: AFP/Getty Images)

Why is the UK so hot today?

The UK has seen temperatures climb above 40℃ for the first time in its history.

Two factors have combined to cause this extreme heat.

  • An area of slow-moving high pressure: this so-called ‘plume’ or ‘heat dome’ has travelled up from North Africa to affect much of South Western Europe. This plume has reached the UK
  • Human activity: Met Office chief meteorologist Paul Davies told Sky News this week that “generating our own heat” has contributed to the heat plume.

We also notice the heat much more in the UK because most homes are not adapted to hot temperatures, having been designed to keep heat in.

The government estimates one in five homes overheat during cool summer weather, meaning the figure is likely to be much higher during the current heatwave.

The Met Office has also said the UK tends to be more humid than the European continent, which means sweating is not as effective in regulating your body temperature because it cannot evaporate as quickly.

Climate scientists say we should expect similarly hot UK heatwaves in future (image: AFP/Getty Images)

Is the heatwave due to climate change?

Most scientists say the heatwave and most of the factors behind it are a direct result of climate change.

Extreme UK heatwaves are likely to become longer, more intense and more frequent over the coming years, they say.

The Met Office says its climate models show the chances of UK temperatures hitting 40°C are 10-times more likely in the current climate, compared to a climate humans haven’t contributed to.

“Climate change has already influenced the likelihood of temperature extremes in the UK,” said climate attribution scientist at the Met Office, Dr Nikos Christidis.

“The likelihood of exceeding 40°C anywhere in the UK in a given year has been rapidly increasing, and, even with current pledges on emissions reductions, such extremes could be taking place every 15 years in the climate of 2100.”

While every 15 years may not sound that frequent, it compares to a frequency of 100 to 300 years for these temperatures at present.

The reason why climate change is having such an effect comes down to how much temperatures have risen since the Industrial Revolution, when mankind first started burning fossil fuels on a mass scale.

Thanks to the heat-trapping effect of the gases given off by these fuels, average global temperatures have risen by as much as 1.2°C - enough to increase the severity of extreme heat events.

“40°C at Heathrow, would have been extremely unlikely or virtually impossible without human caused climate change,” says Dr Friederike Otto, from the Grantham Institute for Climate Change, Imperial College London.

“It’s now an event that shouldn’t have surprised anyone. While still rare, 40°C is now a reality of British summers.

“Whether it will become a very common occurrence or remains relatively infrequent is in our hands and is determined by when and at what global mean temperature we reach net zero.”

Additional reporting by PA