What does the ozone hole have to do with climate change?

There are a few connections between the two, but they are largely separate issues.

The ozone hole refers to the seasonal depletion of ozone molecules in the lower stratosphere above Antarctica. This layer of "good ozone" near the top of the atmosphere acts as a shield, filtering out most of the ultraviolet light from the Sun that could otherwise prove deadly to people, animals, and plants.

Damage to the ozone shield occurs as sunlight returns each spring, triggering reactions that involve chlorofluorocarbons (CFCs) and related molecules produced by industrial processes. These reactions consume huge amounts of ozone over a few weeks' time. Later in the season, the ozone-depleted air mixes with surrounding air and the ozone layer over Antarctica recovers until the next spring.

Because of international agreements to limit CFCs and related emissions instituted with the Montreal Protocol, it's expected that the ozone hole will be slowly healing over the next few decades.

The ozone hole does not directly affect air temperature at Earth's surface, but ozone is actually a greenhouse gas, and so are CFCs, meaning that their presence in the troposphere contributes slightly to the heightened greenhouse effect. But the main greenhouse gas responsible for present-day and anticipated global warming, is carbon dioxide produced by burning of fossil fuels for electricity, heating, and transportation.

Maximum extent of ozone hole over Antarctic in October 2015
On Otober 2, 2015 the ozone monitoring instrument on NASA's Aura satellite determined that the area of ozone depletion over Antarctica had reached its larest single-day extent for the year. Areas with blue and purple indicate the least ozone, while areas in green and yellow represent more ozone. (Courtesy NASA Ozone Hole Watch.

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