n the 1980s, scientists discovered that emissions of refrigerants and accelerants called chlorofluorocarbons (CFCs) had depleted the ozone layer, especially over Antarctica. Ozone depletion, notorious for permitting more cancer-causing ultraviolet light to reach the surface, has a lesser known impact: It cools the stratosphere, the layer of atmosphere between 10 and 60 kilometers (6 and 37 miles) above the surface.
Since the ozone hole began developing, researchers believe the Antarctic stratosphere has cooled between 2C and 6C (3.6F and 10.8F). Such cooling changes the dynamics between the stratosphere and lower layers of the atmosphere and strengthens Antarctica's already fierce winds.
Ever since mariners first attempted to navigate the Southern Ocean, the region has been notorious for its powerful and stormy cyclonic winds during the winter. The "polar vortex" whips around the Southern Ocean and produces sustained periods of freezing temperatures unlike any other place in the world.
Since 1980, the strength of the polar vortex has intensified by about 15 percent due to ozone depletion. The loss of ozone caused atmospheric pressure to decrease over the Amundsen Sea, thereby strengthening the winds on the Ross Ice Shelf, according to NASA Goddard scientist Josefino Comiso, coauthor of a recent study that models the connection between ozone, wind speeds, and climate in the Antarctic. The changes help explain one of the paradoxes of the Antarctic: while sea ice in some areas is growing rapidly, it's retreating at a rapid pace in others.
The new model suggests that colder, stormier, and faster winds are rushing over the waters encircling Antarctic - especially the Ross Sea, where ice growth has been the most rapid. The winds create areas of open water near the coast - known as polynyas - that promote sea ice production.
At the same time, warmer air from higher pressure systems are simultaneously encroaching upon the Antarctic Peninsula, one sliver of the continent that is experiencing rapid warming.
"We see a very mixed pattern of both melting and ice growth in the Antarctic," said Thorsten Markus, head of NASA Goddard's Cryospheric Sciences Branch. "Changes in the cyclonic pattern due to the ozone hole are one of the best explanations we have."