© NASA/Science Photo LibraryA coloured satellite map of atmospheric ozone in the southern hemisphere between mid-August and early October 1998. An ozone "hole" is seen over Antarctica.
Pointing to the recovery of the ozone layer as humanity's one great triumph of environmental remediation may have been premature, a new report warns.
A team led by Joanna Haigh of the Grantham Institute at Imperial College London, UK,
has discovered that while ozone density is indeed improving at the poles, it is not doing so at lower latitudes, roughly between 60 degrees north and 60 degrees south.That encompasses everywhere on the planet between the Shetland Islands off the north coast of Scotland to south of Tierra del Fuego at the foot of South America.
The researchers found that although the decrease in ozone concentration is not as great as that seen at the poles before the banning of ozone-depleting chlorofluorocarbons (CFCs) in 1987, the effects may be worse, because ultraviolet radiation is stronger in the region, and it contains most of the world's population.
Ozone is an inorganic molecule also known as trioxygen, or O
3. It is present in low concentrations throughout the Earth's atmosphere, but is found in much larger levels in the stratosphere, about 20 to 30 kilometres above the planet's surface, where it is formed by the interaction of O
2 with ultraviolet light from the sun.
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