The key facts

  • Signs of polar vortex disruption recorded in November — unprecedented for modern meteorological observations
  • Cold spells are possible in Scandinavia, the British Isles, Germany and Poland
  • The influence of El Niño is being studied; no direct link between the early disruption and climate change has yet been established

A disruption never before seen in November

The polar vortex is a vast area of low pressure and extremely cold air circulating high above the Arctic. Normally it strengthens throughout autumn, peaks around January and gradually weakens toward the end of winter, while major disruptions capable of releasing Arctic air southward usually occur between January and March. This year, however, scientists have recorded signs of disruption as early as November — as Euronews notes, this is an unprecedented event in the modern history of meteorological observations.

What this could mean for the weather

Professor Andrew Charlton-Perez, a meteorologist at the University of Reading, said in an expert commentary published by the universitythat scientists have never before observed such an early-in-the-season sudden stratospheric warming. When the vortex weakens or shifts, the jet stream can become distorted, allowing cold Arctic air to penetrate into lower latitudes. The disruption may raise the likelihood of cold spells in northern and central Europe — including parts of Scandinavia, the British Isles, Germany and Poland — as well as in certain regions of North America and Asia.

It is too early to talk about consequences

The impact of stratospheric processes emerges with a delay of several weeks before it reaches the lower layers of the atmosphere, where weather systems form, and the final effect depends on the position of high- and low-pressure areas. Scientists are also studying the possible influence of a strong El Niño developing in the Pacific Ocean, which is capable of altering atmospheric circulation. Climate change is considered a possible factor in some atmospheric processes, but a direct link to the current exceptionally early disruption has not yet been established. Meteorologists continue their observations: the coming weeks will show whether the disruption leads to significant changes in winter weather across the Northern Hemisphere.