What’s with the hole in the ozone layer?
The ozone layer is the layer of the atmosphere that blocks ultraviolet rays from the sun, and it is critical to life on earth. Without the ozone layer, there would be increased harmful ultraviolet radiation that would cause genetic damage to living creatures and organisms. Ozone depleting substances, such as chlorofuorocarbons (CFCs), reduce the amount of ozone in the atmosphere and in 1985 a significant thinning, or hole, was discovered in the ozone layer over Antarctica. The ozone hole prompted the Montreal Protocol to be signing in 1987, which committed nations world wide to phase out ozone depleting substances (currently 191 countries have signed the Montreal Protocol). We have been largely successful, although not completely: current emissions of ozone depleting substances is only 7% of the peak level in 1994! This dramatic reduction demonstrates what is possible when the world decides to act together, and gives hope to stopping global warming.
