The Earth's atmosphere just pulled a surprising U-turn! The polar vortex, a swirling mass of cold air circling the Arctic, has unexpectedly reversed its direction.
While Australia and New Zealand battles record-smashing heat, interminable drought and deadly bushfires, the United States is in the grip of a polar vortex, with temperatures plunging to their lowest in history.
When the strong winds that circle the Arctic slacken, cold polar air can escape and cause extreme winter chills in parts of the Northern hemisphere - a new study finds.
