NASA - National Aeronautics and Space Administration

A relatively warm Antarctic winter in 2004 kept the thinning of the protective ozone layer over Antarctica, known as the ozone 'hole,' slightly smaller than in 2003. Each year the 'hole' expands over Antarctica, sometimes reaching populated areas of South America and exposing them to ultraviolet rays normally absorbed by ozone. Scientists have new tools to study this annual phenomenon, and the human-produced compounds that contribute to ozone breakdown are decreasing.

Images above and below: On September 22, 2004, ozone thinning over Antarctica reached its maximum extent for the year at 24.2 million square kilometers (9.4 million square miles). The largest maximum area on record was 29.2 million square kilometers, in 2000. On October 5, 2004 the ozone layer reached a low value of 99 Dobson Units. Data come from NASA's Total Ozone Mapping Spectrometer (TOMS) on the Earth Probe satellite, from Aug. 1 - Oct. 5, 2004. Click on images to enlarge. Gray scale image can be found below. Credit: NASA

Related images:

Click here for full color high resolution image of the ozone hole (14 MB).

Click here for a high resolution of a gray scale image of the ozone hole (4 MB).

Sarah Dewitt
Goddard Space Flight Center