Is the "Beast from the East" caused by global warming? Short answer: maybe. Long answer: it's all about sudden stratospheric warmingby Kelly Oakes / February 26, 2018 / Leave a comment
This time last week you’d have been forgiven for thinking spring was just around the corner. But now the UK has been plunged into freezing cold temperatures and parts of the country are under snow, thanks to a blast of cold air forecasters are calling the “beast from the east.” The Met Office says in some areas it’ll be the coldest spell we’ve had for several years. Does it have anything to do with climate change?
It turns out our current weather can be blamed on a meteorological event called “sudden stratospheric warming.” It all starts with a pool of cold air about thirty kilometres above the North Pole. A specific set of meteorological circumstances lead to the air being compressed, which in turn makes it up to 50 degrees warmer in a matter of days. When that happens, it sets off a chain of events that lead more often than not to wintry conditions for all of us on the ground.
What is sudden stratospheric warming?
Usually the UK’s weather comes in from the west and we get relatively mild air from the Atlantic. But after sudden stratospheric warming happens, the newly warm air above the North Pole disturbs the jet stream, blocking the mild Atlantic weather from reaching us and allowing cold air in from eastern Europe. This cold air gets trapped and builds up, eventually coming down to ground level. “The jet stream has weakened and actually buckled,” says Met Office spokesperson Oli Claydon.
That’s how this particular cold snap came to be. But you’re probably aware that extreme weather events are due to increase in frequency because of climate change.
Just last week researchers from Newcastle University published a paper analysing how floods, droughts and heatwaves are all set to become more common in European cities in the years ahead.
As well as looking to the future, scientists are now beginning to figure out which past extreme weather events can be blamed in some way to human-induced climate change.
Using the emerging science of probabilistic event attribution, scientists at the University of Oxford have shown that Storm Desmond in 2015 and the floods in the southeast in 2014 were most likely made worse because of human activity.