Ozone depletion
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Ozone depletion consists of two related events observed since the late 1970s: a lowered total amount of ozone in Earth's upper atmosphere, and a much larger springtime decrease in stratospheric ozone
Lowest value of ozone measured by TOMS each year in the ozone hole
Ozone hole in North America during 1984 (abnormally warm, reducing ozone depletion) and 1997 (abnormally cold, resulting in increased seasonal depletion). Source: NASA
Ozone levels stabilized in the 1990s following the Montreal Protocol, and have started to recover. They are projected to reach pre-1980 levels before 2075.
Air pollution 3
Antarctica
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Antarctica is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. An
Ozone depletion
…conversion of unreactive chlorine compounds into reactive chlorine compounds, which can easily deplete ozone. Moreover, the polar vortex formed over Antarctica is very tight and the reaction occurring on the surface of the cloud crystals is far different from when it occurs in atmosphere. These conditions have…
Vinson Massif from the northwest, the highest peak in Antarctica
Glossopteris sp. leaf from the Permian of Antarctica
Blue ice covering Lake Fryxell, in the Transantarctic Mountains
Temperate conditions near the coast in December 2006