Our atmosphere is made up of different layers, One layer, between 6 and 30 miles above the Earth, is made up of ozone gas. This ozone layer protects us from the Sun’s harshest rays can, called ultraviolet or UV rays. These rays can cause sunburn and skin cancer.
When old refrigerators, air conditioners, and similar items are thrown away, gases from them called chloroflourocarbons, or CFCs rise into the air and destroy some of the ozone in this layer. Most countries no longer produce CFC's, but the gas can stay in the atmosphere for years - destroying ozone and adding to the greenhouse effect.
Each August, a hole in the ozone layer forms over Antarctica (it usually closes by December). Since it was discovered in the 1980s, it has doubled to about the size of North America. It sometimes extends over souther Chile and Argentina. On some days, people in Punta Arenas, Chile (the world's southernmost city), may limiy their sun exposure to no more than 20 minutes between noon and 3 P.M. Other days, they don't go out at all!
