Climate change: UK summers could be over 5C warmer by 2070

In its first major update on climate change in almost 10 years, the Met Office has warned of significant temperature rises in the decades ahead.

The UK Climate Projections 2018 study is the most up to date assessment of how the UK may change over this century.

It says that under the highest emissions scenario, summer temperatures could be 5.4C hotter by 2070.

The chances of a summer as warm as 2018 are around 50% by 2050.

One key figure in the report is the rise in summer temperatures - up to 5.4C warmer than the average between 1981-2000.

This would only happen, according to the Met Office, if the world was to continue increasing emissions of carbon dioxide rather than reducing them as most governments intend.

So for a central location in England like Nottingham, the Met Office says that, under a high emissions future (where greenhouse gases released into the atmosphere over coming decades are at the high end of all possible scenarios), temperatures could rise by between 1.1C to 5.8C.

For other central locations in the nations of the UK, there are similar ranges of projected temperature rises.

In Scotland, at Pitlochry, the summer rise ranges from 0.6C to 4.8C warmer. Around Aberystwyth in Wales, they range from 0.9C to 5.9C warmer while Cookstown in Northern Ireland could be 0.8 to 4.9C hotter.

But even under a low emissions scenario, the Met Office says that the UK will see an increase in the average yearly temperature of up to 2.3C by 2100.

Summers as warm as the one just past, are likely to be very common, with a 50% chance of occurring.

"With really hot summers like this year's - in the 1990s that was a less than 5% chance of getting those," said Met Office chief scientist Dr Stephen Belcher.

"Now we are up to a 15-20% chance. By 2050 that's a normal summer…By late century it depends what we do about greenhouse gases."

These warmer summers of the future are likely to be much drier too, with average summer rainfall dropping by 47% by 2070. Winters could be warmer by up to 4.2C but they will also see more rainfall, increasing by up to 35% by 2070, under the worst emissions scenario.

Raised sea levels are also one of the consequences of a warmer world and according to the report, they could increase by 1.15 metres in London by 2100.

The report says the UK is set to see an increase in both the frequency and magnitude of extreme water levels.

Just a few weeks ago the UK's Committee on Climate Change (CCC) warned that by 2080 up to 1.2 million homes may be at increased risk of flooding.

"The UK18 projections are further evidence that we will see more extreme weather in the future - we need to prepare and adapt now, climate change impacts are already being felt with the record books being re-written," said Emma Howard Boyd, chair of the Environment Agency.

"The Environment Agency cannot wall up the country, but will be at the forefront - protecting communities, building resilience, and responding to incidents."

Environment Secretary Michael Gove praised the new study as an "invaluable tool" as it will help with decisions on large infrastructure.

"It is clear that the planet and its weather patterns are changing before our eyes," he said, launching the report at the Science Museum in London.

"We know, more than ever before, the urgency of acting."

Mr Gove has been stressing that Britain has a good track record on climate change, having cut emissions by 40% since 1990 while continuing to grow the economy. However, other political figures say that the new report underlines how much more needs to be done.

"These projections paint a devastating picture of what climate breakdown means for the UK if we continue down the path we're on," said Green party MP Caroline Lucas.

"Michael Gove's vague talk of mitigating the worst impacts of floods, droughts and storms are far from reassuring."

Some researchers were also critical of the report, saying that it gave the impression that scientists can give more detail about the future than is possible.

"It (the report) feeds our desire for specifics and for high resolution pictures," said Prof David Stainforth from the Grantham Research Institute on climate change and the environment.

"It is valuable in bringing to life the types of changes we want to avoid. It is, however, based on research at the edge of scientific understanding, using methods whose reliability has been questioned. It is not reliable and robust in the way that knowledge of the climate change threat is, so it creates its own risks."

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