NASA has found that the amount of ultraviolet radiation penetrating the Earth's protective ozone layer has increased 7 percent to 10 percent over the last 10 years. NASA scientists confirmed that a combination of man-made chemicals and airborne particles from volcanic eruptions have thinned the ozone layer, thus letting in the sun's harmful UV rays.
Ultraviolet radiation can cause skin cancer and cataracts.
Ozone is found between the Earth's surface and an altitude of 37 miles. It absorbs much, but not all, of the sun's radiation. The finding is based on analysis of data from an instrument known as the Total Ozone Mapping Spectrometer, which is aboard NASA's Nimbus-7 satellite. Although the use of ozone-destroying chemicals has been banned internationally, scientists say it could take up to 15 years to see a corresponding decrease in the levels of ultraviolet radiation reaching the Earth. The Associated Press contributed to this report.