Publication Date January 6, 2014

What is a polar vortex? The arctic winds that brought cold air and chaos to the US

United States

Some scientists believe that warmer-than-average conditions in the Arctic can weaken the polar vortex, so causing colder-than-average conditions at lower latitudes. They think this could help to explain the extreme conditions of the 2009-2010 winter when the normal pattern of Arctic winds broke down causing a weakened polar vortex to allow a frigid body of air to move south. This brought record snow conditions to northern Europe, eastern Asia and eastern North America