Stratospheric winds can warn of extreme energy demand in Europe

Stratospheric winds can serve as an early warning signal for extreme energy demand in Europe, according to new research. Strong and stable westerly winds typically circle high above the Arctic in the winter, forming the stratospheric polar vortex. However, about once every two years, this vortex temporarily breaks down in an event called a sudden stratospheric warming (SSW). This causes the cold air near Earth's surface to spill south, affecting locations like Europe and North America.

A study led by the University of Exeter found that SSWs increase the likelihood of extreme electricity demand (defined as at least 20% above average) in northern and central Europe by 1.5 to 3 times. The paper, published in Meteorological Applications, highlights that cold weather following SSWs often arrives a few weeks after the polar winds shift, providing governments and energy providers with a warning to prepare for extreme demand.

For instance, the 2018 "Beast from the East" demonstrated this phenomenon, with cold weather following the polar vortex's split. Dr. Regan Mudhar, now at the University of Lausanne, noted that while SSWs don't always impact surface temperatures, this particular event led to severe cold weather in the U.K. and northern Europe. The study analyzed the relationship between SSWs and extreme electricity demand driven by heating needs, revealing a clear link.

The impact of cold spells varied across nations. Scandinavian countries, well-adapted to extreme cold, experienced a smaller increase in energy usage during colder periods. In contrast, France, with its highly electrified energy system, saw a steeper rise in demand. Dr. Hannah Bloomfield from Newcastle University explained that the U.K. is currently relatively well-prepared for cold weather due to reliance on gas central heating.

However, as society transitions to net zero, many traditional gas heating systems must be electrified, making future cold weather events with low wind particularly challenging to manage and cost-effective.

Mudhar emphasized that while global warming driven by greenhouse gases will continue, SSWs will likely still occur, bringing cold weather with them. This underscores the importance of preparing for extreme events even as the world moves toward renewable energy sources.