Much of Europe has been enjoying warmer than usual temperatures in recent days - but an unseasonably cold front is incoming, bringing with it snow, and potential disruption.
The UK for example has had record temperatures in some areas for the time of year, and the Met Office has indicated a “big change” is coming over the Easter weekend.
It will be “much colder than usual” and “much wetter too” by early next week, according to forecaster Alex Deakin, who said “very cold air is on its way” from the Arctic.
What exactly is driving this strange weather?
“We can’t tell until the weather event has happened,” Alun Hubbard, a professor of glaciology at UiT, the Arctic University of Norway, told Euronews.
But a new study, published by Hubbard and colleagues in the journal Nature Geoscience, could hold some clues.
Melting Arctic ice fuelled the Beast from the East
The team tracked water vapour from the Arctic in real time in 2018 and followed it as it ended up as massive snowstorms that covered much of Europe that year in an event that was dubbed the Beast from the East.
They used a geochemical isotopic fingerprinting technique to do this: because isotopes in water vapour from melted snow are different from those in water vapour from the sea, they were able to quantify exactly how much excess moisture had been released from the Barents Sea during this period.
“One hundred years ago, even 40 years ago in winter, the Barents Sea would be frozen. Now it’s become warm, it’s become salty, it’s become a much stronger evaporative source of moisture,” said Hubbard, who explained the ice acts as a “lid” on the ocean, stopping it from evaporating.
About 140 gigatonnes of water evaporated from the sea, or 88% of the moisture that fell as snow on Europe, according to the team’s calculations.
The storm caused havoc in much of northern Europe in February and March 2018, costing the UK’s economy alone more than €1 billion a day.
While the study cannot prove that the incoming weird weather in Europe is a direct result of the same phenomenon, it warns if current warming trends continue the ice-free Barents Sea will be a major source of moisture for continental Europe.
“We used the Beast from the East to illustrate as a case study of what happens,” says Hubbard.
“The Beast from the East is embedded in our memory, Heathrow got shut, people were dying, people were stuck on motorways,” says Hubbard.
“While we’re not seeing it every year, what it means is there will be a lot more snowfall associated with these events in the future.”
Melting Arctic ice is affecting Europe now
He adds that while the public gets “saturated” with warnings about climate change, it can often feel like something that is happening far away. But the melting of the Arctic ice, as this study shows, has serious effects in Europe.
“People feel insulated and remote from the actual effects of what’s going on,” says Hubbard.
“And OK we’re getting some hotter summers. But it’s all part of more extreme weather. Extreme weather is very bad for infrastructure, it brings countries to a standstill, very bad for agriculture, it really is creating a more inhospitable place.”
He points out it is a global phenomenon. When the US was hit by unprecedented cold weather last winter - an event in which the power grid in Texas was overwhelmed by the added need for heating - it was a similar phenomenon.
“Texas was getting these nutty, crazy cold temperatures with Arctic cold outbreaks, and it’s carrying more moisture because the sea ice is disappearing north of North America as well.”
Now, when these cold weather events with high levels of moisture come in from the Arctic region in March or April, “when traditionally the sea ice would have been at its maximum extent”, we will know it will be at least “partially driven by what’s going on in the Arctic and the reduced sea ice there,” he adds.
“It really is like a forensic investigation into a crime scene, where there’s very little evidence so you have to piece the story together. We did it very well and very conclusively in this study.
“This geochemical fingerprinting of the vapour that came from the Arctic is almost like getting the smoking gun of this effect. It’s something people have been talking about and speculating for a long time, but for the first time what we’ve shown is what goes on in the Arctic actually does have a big influence in the lower latitude, southern Europe and the UK.”