ozone hole

American  

noun

1. any part of the ozone layer that has become depleted by atmospheric pollution, resulting in excess ultraviolet radiation passing through the atmosphere.

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ozone hole Scientific  

1. A severe depletion of ozone in a region of the ozone layer, particularly over Antarctica and over the Arctic. The depletion is caused by the destruction of ozone by CFCs and by other compounds, such as carbon tetrachloride (CCl ₄) and carbon tetrafluoride (CF ₄). The amount of ozone in ozone holes is about 55 to 60 percent of the normal concentration in the ozone layer. Although the full effect of increased ozone depletion is not yet known, the amount of ultraviolet radiation the Earth receives is greatly increased by ozone depletion, creating a heightened risk of skin cancers and likely contributing to global warming.

2. See Note at ozone

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ozone hole Cultural  

1. A depletion of ozone that occurs over Antarctica in the winter. The ozone returns to normal levels in the summer, and the amount of depletion varies from year to year. The hole is thought to be caused by a combination of the peculiarities of atmospheric circulation (see atmosphere) near the South Pole and chemical reactions involving chlorofluorocarbons in the atmosphere and ice crystals in clouds.

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Etymology

Origin of ozone hole

First recorded in 1985–90

Example Sentences

Climate change biologist Prof Sharon Robinson told BBC News: "When I tell people I work on the ozone hole, they go: 'oh, isn't that better now?'"

From BBC • Apr. 26, 2024

A 2022 United Nations assessment concluded that the ozone layer, including an ozone hole over the Antarctic, will be largely restored over the next several decades.

From Science Daily • Apr. 23, 2024

The ozone hole and thinning ozone layer has improved a bit thanks to the 1987 Montreal Protocol, when countries in the world agreed to stop producing many of the chemicals that deplete ozone, Newman said.

From Seattle Times • Nov. 1, 2023

Massive wildfires that raged across southeast Australia in 2019–20 unleashed chemicals that chewed through the ozone layer, expanding and prolonging the ozone hole.

From Scientific American • Mar. 10, 2023

The ozone hole of over- information broke the protective bubble of literacy.

From The Civilization of Illiteracy by Nadin, Mihai