Ozone destroying chlorofluorocarbons (CFCs) move around the world through the stratosphere. The CFCs moving over the poles become trapped there by an annual atmospheric phenomenon called the polar vortex, winds that circle the Poles keeping the air there virtually stationary for a time. Cold temperatures exacerbate the chemical reaction that causes CFCs to harm ozone. As the Antarctic air is much colder than that of the Arctic regions, more damage is done to the ozone layer around the South Pole.