The Coastal Post - September 2000

Early Ozone Hole

By Jim Scanlon

The Antarctic Ozone Hole is forming this year further to the north, outside its traditional confines. Images from NASA's web site shows serious ozone depletion occurring as far north as 50S a populated region of southern South America where there are a number of small cities.

Catastrophic ozone depletion takes place when sunlight strikes ice crystals of Polar Stratospheric Clouds on which chlorine compounds are deposited during the long winter's night.

Previously these clouds have not formed so far north, but this year something different is going on.

Check out the months of July through August at http://toms.gsfc.nasa.gov/, click on "Earth Probe," set day and month and change "Global Ozone gif" to "South Pole Ozone gif."

One can observe the formation of small ozone holes outside the area of winter darkness during the month of July. The depletion gets worse from as August progresses. By September sunlight will have reached the stratosphere over Antarctica, initiating the Ozone Hole as we have known it up till the present.

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