Without the ozone layer in the upper atmosphere, chances for life on Earth would be bleak. This is because, in addition to the light we see, the Sun also emits energetic and short-wavelength ultraviolet radiation that is invisible to the human eye. This UV radiation can damage cells and destroy the DNA of living things. It also damages ecosystems in the ocean and on land and can cause skin cancer in humans.

The ozone layer is in the stratosphere at a height of 15 to 50 kilometers and contains about 90 percent of the atmosphere’s ozone. Ozone absorbs a portion of the Sun’s UV radiation that would be dangerous to living things. Scientists noticed in the 1980s that the ozone layer was becoming depleted, especially over the Antarctic around the South Pole. This increased the risks associated with higher UV radiation. The ozone hole was caused by substances known as chlorofluorocarbons (CFCs), which can damage ozone. Researchers had already discovered in the 1970s that these substances, which were used in refrigerators and spray cans, can destroy ozone.

Today the Montreal Protocol and its subsequent agreements regulate the use of ozone-destroying substances like CFCs and their replacements. Some of these substances not only destroy ozone, they also have a high global warming potential, which means they can trap heat in the atmosphere and contribute to the global rise in temperatures. By banning ozone-damaging chemicals, policymakers not only rescued the ozone layer, they also helped protect the climate.

A specific factsheet including Belgian situation will be available for download June 24.

External links (that will be elaborated further)