The Ozone Layer

"...I drift into a happy, relaxed dream. I swim inside the cell of a plant, watching cytoplasts use light and water and carbon dioxide to make food. In doing so, just as a by-product, an accident almost, they liberate oxygen. I watch the tiny plants of the ocean breathe life into the atmosphere, 3.8 billion years ago. Millions of years pass. The sun's rays grow less deadly, and the barren, flat rocks of the earth are ready for life."
The Secret Under My Skin, p.52

Life on land was not possible until the ozone layer was created in the earth's upper atmosphere. The ozone layer blocks out toxic short-wave ultraviolet radiation from the sun. Without the ozone layer, life on land would not be possible. Today, the ozone layer is in danger.

For an introduction to the ozone layer, visit the University Corporation for Atmospheric Research's Introduction to Ozone page. 

The Ozone Hole

Over the past few decades, scientists have noticed growing holes in the ozone layer at the north and south poles. These holes happen because chemicals that destroy ozone collect in the giant whirlwinds that form at each pole during the dark wintertime. When the summer sun hits these chemicals, they photo react to destroy the ozone. The hole in the ozone layer grows smaller in the dark months of winter, but it isn't going away.

This summer, the hole in the ozone layer above Antarctica was larger than ever, more than 10 million square miles in size. Scientists have now issued a warning to people living in southern Chile: don't go out in the daytime without protection. Because of the hole in the ozone layer, it's now possible for people living at those latitudes to get sunburned even on cloudy days. Scientists predict, within the next ten years, the same will happen to people living in the arctic.

For more advanced information about the ozone layer and its importance to our environment, take the Ozone Hole Tour, a web site maintained by the Centre for Atmospheric Science at the University of Cambridge in England..

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