Word: ultraviolet
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...Antarctic ozone hole has gone global. Under assault by man-made chlorofluorocarbons, levels of the vital stratospheric gas have begun to decline over temperate latitudes both north and south of the equator, including the skies above most of the continental U.S. The thinning ozone layer lets more solar ultraviolet light reach the ground, and the incidence of skin cancer and cataracts is likely to rise as a result...
...Planet Earth, an ambitious, long-range program to monitor the planet's pulse. This particular satellite carries four instruments to gather information about the atmosphere's vital ozone layer. The most important goal is to measure how badly this fragile band, which protects the earth from the harmful ultraviolet rays in sunlight, is being depleted by the industrial chemicals known as CFCs...
...loss was occurring both farther south, over the most populous regions of the U.S., and later in the spring -- when more people spend time outside -- than had been thought. Worse, the additional thinning of this protective layer of gases is expected to increase substantially the amount of harmful ultraviolet radiation reaching the earth's surface, threatening a vast array of life-forms and boosting the number of skin-cancer deaths in the U.S. alone by 210,000 over the next 50 years...
...faintest notion what causes the initial genetic changes to occur. "In lung cancer we have a reasonable idea that the major cause is cigarette smoking," says Dr. Philip Leder, chairman of Harvard's department of genetics. "In skin cancer we understand that the major cause is ultraviolet light, which is absorbed by DNA and causes it to break. But with breast cancer we don't have any idea what the precipitating factors...
...millions of Americans bake on the beaches this summer, many are still blissfully unaware that solar ultraviolet rays can cause something far worse than sunburn. In 1990 some 600,000 new cases of skin cancer will be diagnosed, most of them caused by exposure to the sun, and 8,800 will die. The light skinned and fair haired are the most vulnerable, but wearing sunscreens, hats and protective clothing can lessen the risk, especially during childhood and teenage years...