Ozone depletion wind activity. On March 15, 2011, a record ozone layer loss was observed, with about half of the ozone present over the Arctic having been destroyed. The change was attributed to increasingly cold winters in the Arctic stratosphere at an altitude of approximately , a change associated with global warming in a relationship that is still under investigation. By March 25, the ozone loss had become the largest compared to that observed in all previous winters with the possibility that it would become an ozone hole. This would require that the quantities of ozone to fall below 200 Dobson units,
Views of Lyndon LaRouche and the LaRouche movement Science & Technology", which conducted what has been called "a very effective campaign of misinformation on the issue of ozone depletion", published "The Holes in the Ozone Scare" in 1992. The book, by LaRouche followers Rogelio Maduro and Ralf Schauerhammer, said that chlorofluorocarbons (CFCs) were not destroying the ozone layer and opposed the proposal to ban them. It asserted that most chlorine in the atmosphere came from oceans, volcanoes, or other natural sources, and that CFCs were too heavy to reach the ozone layer. It went on to say that even if the ozone layer were depleted there would not