Overview:

• Location of Ozone Layer

• Ozone Destruction Mechanism

• Balance in the Stratosphere

• Annual Data on Ozone Levels

• Oct. 15 Annual Data on Ozone Levels

• Annual Ozone Hole Size Data

• Annual Minimum Levels

• Switzerland Annual Data

• MPEG Animation of 1994 Hole

• A Bigger Animation

• Ozone Mythology

1995 Hole data:

Why do we see the hole in the Antarctic Spring?

Chlorine from CFCs is stored on stratospheric cloud surfaces during the long polar night and then released to attack ozone when the sun returns in spring. The process involves a series of unusual chemical reactions taking place at temperatures as low as -85 degrees C (188K). Normal ozone levels are restored in the summer when the Antarctic atmosphere, isolated during the winter inside a cold "polar vortex", becomes mixed with ozone-rich air from other latitudes.

The Antarctic spring of this year is arriving, and with it the annual depletion of ozone within the south polar vortex. In recent years, the destruction of ozone within the lower stratospheric region from 14 to 20 km has been virtually total.

Internet Resources Relevant to the Ozone Problem:

• Ozone Hole Image Archive
• Frequently Asked Questions
• Canadian Weekly Ozone Watch
• Ozone Page from Sweden; nice collection of references
• NASA Fact Sheet
• EPA Straospheric Ozone Page
• What about Bromides?
• Ozone Reality Check

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