A leading British scientist predicted Thursday that an ozone hole would start developing over the North Pole, similar to the badly damaged ozone layer over Antarctica.
Jonathan Shanklin -- one of a trio of British scientists who discovered the Antarctic ozone hole in 1985 -- told the BBC: "We think that within the next 20 years we're likely to see an ozone hole perhaps as big as the present one over Antarctica, but over the North Pole."
The cause, he said, was partly ozone erosion as well as a byproduct of global warming.
An obscure aspect of global warming is that even though it increases the temperature at the Earth's surface, it paradoxically causes colder temperatures in the lower stratosphere, where the ozone layer is located.
These lower temperatures, especially in winter, cause stratospheric clouds to form in the polar regions, initiating a reaction with chlorine molecules released by manmade gases, he said.
"Chemistry can take place on them (the clouds) that activates the chlorine and makes it very much easier for it to destroy the ozone," Shanklin said.
The Antarctic hole has been expanding dramatically in the past few years.
This year's was the largest recorded. US satellite measurements last month estimated it three times bigger than the entire land mass of the United States.
However, such is Antarctica's isolation that only a small number of people, living in the Falkland Islands and the tip of South America, are affected so far.
But a similar-sized hole over the North Pole would affect densely populated parts of Western Europe, northeast Asia and North America.
Ozone molecules make up a thin layer of the atmosphere that absorbs harmful ultraviolet radiation from the Sun, a potential cause of skin cancer, sunburn, cataracts and damage to forests and crops.
Man-made gases such as chlorofluorocarbons (CFCs), halons and bromides are the chief cause of ozone layer destruction.
The first global agreement to restrict CFCs came with the signing of the Montreal Protocol in 1987, ultimately aiming to reduce them by half by 2000.
Until recently, criminologists hope these curbs would lead to a recovery of the ozone layer within 2050. but recent investigations suggest the problem is much worse than previously thought.
The BBC was to broadcast its interview with Shanklin on its domestic service, Radio Four, late Thursday. His remarks were released on the organization’s website -- LONDON (AFP)
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