How the last ice age could save the North from global warming
WHEN it comes to surviving climate change, communities in the north of Britain will bounce back far more quickly, experts have predicted, and it’s all thanks to the last ice age.
A report setting out the expected impact on the UK as the climate warms has found that areas squashed down by the huge ice sheets that covered northern regions until 11,700 years ago are now rebounding with sufficient vigour to protect them from sea level rise.
Three-mile-thick glaciers once covered huge swathes of Britain, and in the last big freeze pushed almost as far south as Cardiff and Norwich.
The recovery process – known as isostatic rebound – could see land rising by nearly 4in (10cm) in some northerly areas by the end of the century, providing a huge mitigating force against sea level rises. While areas in the South, such as London, will see sea level rises of 11- to 27in (30- to 70cm) even if Paris climate targets are achieved, northerly areas such as Edinburgh will only see 3- to 19in (8- to 49cm) rises.
Outlining the climate change projections at the Science Museum in central London, Prof Stephen Belcher, the Met Office chief scientist, said: “Sea level is a pervasive aspect of climate change. We have seen sea levels rise continuously through the 20th century. There is a strong contrast between the south of England and the north of England and Northern Ireland, roughly a factor of two thirds of an increase in sea level in the north and Scotland.
“The reason for that is slightly the melting of sea ice where warming occurs but also because of a rebound of the land. In the last Ice Age the land was weighed down by ice and what we’re seeing now is rebound, more in the North than in the South and that gives us less sea level rise in the north of England.”
The projections, compiled by scientists from the Met Office, Defra and the Environment Agency, show a future of hotter summers and wetter winters.
The findings show all of the UK’S top 10 warmest years on record have been since 1990, and temperatures in the recent decade are 0.8C (1.4F) warmer than they were in 1961-1990.
In the past few decades, the average annual rainfall in the UK has increased, particularly in Scotland, where the most recent decade was 11 per cent wetter than 1961-1990, though there has also been natural variation over time.
By 2070, UK average temperatures could be as much as 5.4C (9.7F) hotter in summer and up to 4.2C (7.6F) warmer in winter if the world continues to put out increasing levels of greenhouse gas emissions.
Michael Gove, the Environment Secretary, said: “This cutting-edge science opens our eyes to the extent of the challenge we face, and shows us a future we want to avoid. By having this detailed picture of our changing climate, we can ensure we have the right infrastructure to cope with weather extremes, homes and businesses can adapt, and we can make decisions for the future.”
Rainfall is expected to change too, with an increase of as much as 35 per cent in winter and a drop of up to 47 per cent in summer if emissions are high.
Hot summers are expected to become more common. The probability of a summer as hot as this year has increased from below 10 per cent in recent decades to 10-20 per cent now, and the chances of a 2018-style heatwave summer is likely to rise to around 50 per cent by mid-century.
‘In the last Ice Age the land was weighed down by ice and what we’re seeing now is rebound’