The hole in the Earth's ozone layer is growing faster than ever and is already twice the size it was at this time last year, according to the U.N. weather agency. The hole was first observed over Antarctica in the 1980s.
There has been a reduction in the use of ozone-destroying chemicals such as chlorine and bromine, but the hole is growing because these chemicals have a life of 60 to 100 years, scientists say. The hole usually appears at the end of August and persists until January or February of the following year, when it is dissipated by winds. So far this year the hole has expanded to 3.9 million square miles--roughly the size of Europe--according to the World Meteorological Organization.