Are the ozone hole and global warming related?
The ozone hole and global warming are not the same thing, and neither one is the main cause of the other. The ozone hole is an area in the stratosphere above Antarctica where chemical reactions initiated by chlorofluorocarbons (CFCs) have destroyed ozone molecules. Global warming is the rise in average global surface temperature caused primarily by the build-up of human-produced greenhouses gases, mostly carbon dioxide and methane, which trap heat in the lower levels of the atmosphere. There are some connections between the two phenomena, however. The CFCs that destroy ozone are also strong greenhouse gases. Although they are present in the atmosphere in very small concentrations (several hundred parts per trillion, compared to several hundred parts per million for carbon dioxide), CFCs account for about 13% of the total energy absorbed by human-produced greenhouse gases. The ozone hole itself has a minor cooling effect (about 2 percent of the warming effect of greenhouses gases) becau
