UK will see four heatwaves a year and twice as many flash floods by 2070s, Met Office predicts

The UK will experience increasingly extreme weather by the 2070s, including four heatwaves a year and almost twice the amount of current flash flooding, according to new data from the Met Office.

The organisation has been working on long-term climate projections for the UK and has now published its most detailed estimates yet.

Scientists working on the projections examined the UK using a grid, which broke down Britain into 2.2km squares, so that they could better project local climate events.

“Extreme weather events, such as higher maximum daily temperatures and intense rainfall events leading to flash flooding, are projected to be serious consequences of climate change affecting the UK in coming decades,” said Lizzie Kendon, a climate scientist at the Met Office.

“The new 2.2 km projections will allow us to look at the potential for local temperature extremes to exceed 40C.”

To assist with future climate planning, researchers have set out a range of future outcomes, depending on different rates of greenhouse gas emissions.

Under a high emission projection, the amount of likely flash flooding will almost double by the 2070s.

Daily maximum temperatures will also increase and hot spells exceeding 30C may occur four times a year instead of once every four years.

“Our latest projections shows that by 2070, these events could occur up to four times every year: a 16-fold increase,” Jason Lowe, the head of climate services at the Met Office, said.

But not every summer will see heatwaves.

“Whilst the trend is towards warmer and wetter winters, and hotter and drier summers, we will still get some cold years,” Mr Lowe added.

2019 has already seen the UK’s highest ever daily maximum temperature of 38.7C, which was recorded in Cambridge on 25 July.

“The level of spatial detail we are working with is 10 times finer than the resolution of previous model projections,” Ms Kendon said.

“What we’ve been able to do with the UK’s future climate is to model the impacts of extremely localised events, like the one in Boscastle in August 2004, which saw one month’s rainfall fall in just two hours on the Cornish coastal village: you just can’t capture these in coarser projections.”

The Met Office said its new projections would help local authorities plan for future climate change.

“These new local 2.2km projections show in unprecedented detail the extent of the challenge we face,” said Theresa Villiers, the environment secretary.

“We must adapt to the changes in our climate, but must also continue to take concerted action to reduce our emissions.

“The data will play a crucial role, helping us make decisions on what more we all need to do to cope with impacts from a changing climate and extreme weather events.”

A major study published last month predicted that Britain would experience some of the worst river flooding in Europe in the coming years.

“The projections have already shown that extreme weather will become worse and more frequent in the future,” said Emma Howard Boyd, chair of the Environment Agency.

“Having more local information like this will bring home the challenges that we all face in the places we live.

“With the help of these projections the Environment Agency will do everything possible to respond to the challenges of climate change, build resilience, and protect communities now and through the next century in a new flood and coastal strategy.”