Visible sunlight allows us to see the world around us. But there is invisible sunlight as well. These rays can not be seen. Some can be felt as heat, but the ones that can't be felt are called ultraviolet rays. These are the culprits that cause changes to happen to our skin, like wrinkles, tans and even cancer. When a person wears sunscreen, they are protecting themselves from these ultraviolet rays.
A protective blanket of gases, the atmosphere, surrounds our planet. It provides us with the air we breathe, and it protects us from the full blast of the sun's radiation. Way up in the part of the atmosphere, called the stratosphere, a layer of gas filters out most of the sun's damaging ultraviolet rays. This layer of gas is called ozone and is located about five miles to 25 miles above the surface of the Earth. (Bright, 1991).
Only about one-millionth of our atmosphere is made up of ozone. But it has a tremendously important job. Ozonecan absorb, or soak up, the part of sunlight called ultraviolet radiation. Some ultraviolet radiation still gets through, but not enough to do serious damage to Earth. If all of those dangerous rays got through, life as we know it would be impossible.
But there is a significant pending problem in the ozone layer. Each year, a large hole appears in it. It is not an actual hle, but a thinning in the layer that shows up on satellite pictures. The "hole" is located over Antarctica. It covers an area about the size of the United States. Experiments done in Antarctica show that the hole in the ozone layer appears to let in twice as much ultraviolet radiation ans...