This is a computer drawing of the two main chlorofluorocarbon (CFCs) molecules that release chlorine in the stratosphere, ultimately causing the destruction of ozone molecules.
Click on image for full size
Courtesy of COMET program

Ozone in the Stratosphere

Most of the ozone that we know about is found in the the stratosphere, the second layer of the Earth's atmosphere. Ozone forms a kind of layer in the stratosphere. This layer shields us from the Sun's ultraviolet light. This ultraviolet light can cause damage to people like giving them skin cancer or causing tissue damage to their eyes. Ultraviolet light can also be bad for plants and animals.

The ozone layer would be very good at its job of protecting Earth from too much ultraviolet radiation - that is, it would if humans did not contribute to things! Human-released chemicals are speeding up the breakdown of ozone, so that there are "holes" now in our ozone protection shield.

Scientists know about this problem. They have told governments around the world that they need to stop making and releasing these harmful chemicals that break down ozone in the stratosphere. Countries have started doing this, and scientists are hoping that this will eventually heal the "holes" that were made in the ozone shield.

Last modified January 8, 2007 by Jennifer Bergman.

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