Yellow weather warnings throughout the UK
The climate crisis is usually associated with overall planetary warming, but in some areas climate disruption brings abnormal colds. If you’re in the UK, there’s a good chance you’ve been pulling out that winter coat and possibly shovelling a bit of snow!
The coldest temperature in the UK this year was -10.4°C in Drumnadrochit (on the western shore of Loch Ness in the Scottish Highlands) on January 19. That number, however, is expected to be obliterated as temperatures may hit -15°C tonight. This is about six degrees colder than last March, when the mercury bottomed out at -9.1°C in Aboyne, Aberdeenshire.
Maybe you remember Anticyclone Hartmut in 2018, more familiarly known as the “Beast from the East”? Although the Beast from the East event was the confluence of storms, the initial event was the same type of polar disruption currently over the UK. Normally centred over the poles when strong, polar vortices are large counter-clockwise flows of low pressure. This vortex can be weakened by events such as sudden stratospheric warmings (SSWs), during which the temperature in the stratosphere can warm up to 50°C after the slowing and/or reversal of winds in the stratospheric polar vortex. In this current case, the SSW was triggered following a large high-pressure blocking event over Greenland. This system disrupts the polar vortex, causing the frigid polar air to spill south, in this case, unleashing an Arctic blast south over the United Kingdom and continental Europe.
Disruptions to the polar vortex have been happening more frequently and with greater intensity in recent years, in part due to the greater climate crisis. Two of the main contributors include the moderation of the temperature differential as the Arctic warms exponentially. This polar warming is associated with a weaker vortex that is more prone to disruption, and thus, southerly dips. Similarly, the warming Arctic is also associated with a less stable jet stream, which gives rise to more extreme weather.
The Met Office warns that the polar air and potential icy conditions will continue through the weekend and are likely to cause various degrees of travel chaos and uncertainty, as well as electrical outages that could isolate more rural communities. Keep some food, water and warm kit in your car if you need to head out on the road in the event of travel disruptions!
Do you need a place to stay? Find a spot near you at https://www.warmwelcome.uk. With the cost of heating being up 96% compared with last year, a warm place to live is beyond the reach of an increasing number of Britons. Luckily, there are more than 4000 warm banks around the country where you can have a warm place to stay without any cost–and some with wifi and food available (sometimes at a cost). Worried about a four-legged friend in this cold spell? The RSPCA is full of tips to keep your feathered and furry friends safe!