The polar vortex is an area of low pressure. It is located over the Earth’s poles, between the upper troposphere and the stratosphere levels. A weakening in the polar vortex caused by other natural events, such as a volcanic eruption, cause it to almost break away from its normal residence at the poles. When it breaks away, it heads towards the equator. Its at this point that we experience the cold bust of air. 
Contrary to what most believe, the location of the vortex is not actually where humans inhabit on earth. The polar vortex are located on the Earth's magnetic poles. Once you have located the poles you have to then go straight up until you are between the upper troposphere and the stratosphere levels.
It is believed that the reason the polar vortex is moving so much from the poles, is from climate change. It is has claims that because of melting ice caps the less ice there is the easier it can be pushed off the pole.
Although that does play a part, that's not the only reason it shifts. Because of this the ozone levels are decreasing. With everything changing and levels of CO2 rising and being drawn to the poles it becomes highly concentrated and depletes the ozone layer.
Other closely related articles in this wiki include:
- Polar vortex - AMS Glossary. (2015, October 6). Retrieved February 20, 2016, from 
- MacMath, J. (2014, November 12). What is a Polar Vortex? Retrieved January 28, 2016, from 
- Fischetti, M. (2016, February 12). What Is This Polar Vortex That Is Freezing the U.S.. Retrieved September 1, 2016
- Polar vortex visits to U.S. linked to climate change. (2014, September 2). Retrieved February 20, 2016, from 
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