Waves in the Atmosphere Batter South Pole, Shrink 2002 Ozone Hole

A greater number of large "planetary sized waves" in the atmosphere that move from the lower atmosphere into the upper atmosphere were responsible for the smaller Antarctic ozone hole this fall, according to NASA researchers. The September 2002 ozone hole was half the size it was in 2000. However, scientists say that these large-scale weather patterns in the Earth's atmosphere are not an indication that the ozone layer is recovering.

Paul Newman, a lead researcher on ozone at Goddard, said that large scale weather patterns have an affect on ozone when large "planetary sized waves" move up into ozone layer. If the waves are more frequent and stronger as they move from the surface to the upper atmosphere, they warm the upper air. Such weather phenomena are known as "stratospheric warmings."

The stratosphere is an atmospheric layer about 6 to 30 miles above the Earth's surface where the ozone layer is found. Ozone breaks down more easily with colder temperatures. A long wave or planetary wave is a weather system that circles the world. It resembles a series of ocean waves with ridges (the high points) and troughs (the low points).

Typically, at any given time, there are between one and three of these waves looping around the Earth. With more or stronger atmospheric waves, temperatures warm aloft. The warmer the upper air around the "polar vortex" or rotating column of winds that reach into the upper atmosphere where the protective ozone layer is, the less ozone is depleted.

For more in the atmospheric waves and its affects on the ozone, go to: http://www.gsfc.nasa.gov/topstory/20021206ozonehole.html