By Elisa Jiménez Alonso
According to research published in the journal Nature Climate Change, the Arctic polar vortex is shifting towards the Eurasian continent.
The Arctic polar vortex is regularly in the news, especially for causing wild wintery weather and sub-zero temperatures in North America. Put simply, it is an area of low atmospheric pressure, or cold air, that sits in the polar regions. Normally, it doesn’t stray far from the Poles, but occasionally, when the low-pressure system is weakened, parts of it leave the Arctic circle. When this happens, higher pressure systems get in its way and push the cold air southwards (see figure below). This famously happened in 2014, when a cold wave hit North America and caused record low temperatures as well as heavier than usual snowfall.
Image: A strong polar vortex on the left in comparison to a weakened polar vortex on the right with parts of it detaching (NASA/public domain)
Recently, researchers have discovered that the wintertime Arctic polar vortex has weakened over the past three decades. This has increased its likeliness to move from high to middle latitudes. The data showed that the vortex shifted away from North America and towards the Eurasian continent. Scientists expect that this could lead to cooler temperatures in late winter and early spring, which could impact ecosystems, agriculture, and other sensitive sectors.
The data also showed a close relationship between the vortex shift and increasing sea ice melt, especially in the Barents-Kara seas. This correlation, as the saying goes, does not equal causation: at this point the research has not proven how melting sea ice might cause the polar vortex shift. However, the link is worthy of further research, as understanding the relationship would improve our ability to prepare for and adapt to future climate impacts.
Currently temperatures in the North Pole are at a record high, which should offer scientists plenty of opportunity to undertake more research.