National Geographic, April 18, 2014

Record low temperatures in the U.S. in early 2014 added a new phrase to the American lexicon: polar vortex. What is it? Is it really new? In this video by Earth Vision Trust, Mark Serreze, Director of the National Snow and Ice Data Center, explains the behavior of the cold polar air jet stream.

Earth Vision Trust is a non-profit founded by National Geographic photographer and grantee James Balog that seeks to educate and inspire the public through innovative visual exploration of the changing environment.