|
|
Study: Ozone Depletion May Slow
The rate of increase of the ozone-destroying chemical CFC-12 in the upper atmosphere is slowing, German scientists report, suggesting that the Montreal Protocols are beginning to have an effect.
By Associated Press
Start Date: 8/19/98
(Aug 19, 1998) -- Increases in the ozone-destroying chemical CFC-12 in the upper atmosphere are slowing, German researchers report.
"The CFC-12 data show a continuous and rather constant increase between 1978 and the early 1990s, while a slowing down of the trend is observed after about 1990," the scientists report in a paper scheduled to appear in the Sept. 1 edition of Geophysical Research Letters.
CFC-12, a chlorofluorocarbon once commonly used in refrigerators and air conditioning systems, is one of the main chemicals found to be damaging the ozone layer in the upper atmosphere.
The high-altitude natural ozone layer forms a barrier against ultraviolet radiation from the sun. Excessive levels of UV radiation cause skin cancer in humans and can damage many plants and animals.
The depletion has been particularly severe over the Antarctic, where it gained the designation "ozone hole."
Fears that severe ozone depletion could spread to populated areas of the world led to the 1989 Montreal Protocol in which countries agreed to reduce or eliminate ozone-damaging chemicals.
Although some 165 countries have agreed to that protocol, levels of CFC-12 continued to increase as the gas escaped from old refrigerators and other equipment that remained in use.
The slowing of those increases, the new paper reports, confirms that the Montreal Protocol has become effective, though it will take years to reduce CFC levels because the chemical can remain in the air 10 to 15 years.
The study was done by Andreas Engel and Ulrich Schmidt of Johann Wolfgang Goethe University in Frankfurt and Daniel McKenna of the Institute for Stratospheric Chemistry in Julich, Germany. Geophysical Research Letters is published by the American Geophysical Union.
[Disclaimer: This article is copyright (c) The Associated Press. The information contained in AP news reports may not be published, broadcast, rewritten or otherwise distributed without the prior written authority of The Associated Press. This text is posted in the public interest.]
 Excelsior, Michael Lindemann's new novel (written under the pen name Michael Paul), depicts a wholly plausible near future in which human cloning is both widespread and widely abused; terrorists have access to target-specific biological weapons; recreational space travel is commonplace; and mounting pressures of global climate change, environmental decline, population growth and civil unrest inspire radical new approaches to urban security.
|
Built by Frontier on a Macintosh on 6/17/00; 11:51:26 AM.
Web Comments  -
Produced by Larry Lowe
Served 1553 times since 8/19/98.
|
Global Warming Devastates World's Coral Reefs
Rising sea water temperature due to global warming threatens to destroy the majority of coral reefs on earth, with potentially huge ecological and economic consequences.
1998 Was the Hottest Year on Record
NASA and NOAA (National Oceanic and Atmospheric Administration) both released data showing that 1998 was the hottest year on record, by a surprisingly large margin.
New Data Points to Reality of Climate Change
Recent studies of atmospheric surface temperatures and ocean temperatures support the claim that global warming is occurring and will probably bring major climate changes in coming years.
Greenhouse Effect May Boost Frequency of El Nino
Global warming could lead to more frequent and violent El Nino weather patterns, according to a new study.
Evidence of Ancient Asteroid Found
Evidence suggests an asteroid hit Argentina 3.3 million years ago, causing regional extinctions and climate change.
Forecasters See Severe Hurricane Season Ahead
Meteorologists say the La Nina cold water condition in the Pacific is likely to produce higher than average hurricane activity in the Atlantic and Caribbean this year.
Water Shortages Will Bring Strife in New Millennium
Limited water supplies will be a major source of international tension in coming years. In March, 1999, Israel and Jordan almost came to blows over water; more trouble lies ahead.
Humankind's Grave Impacts on the Natural World
Human activity has altered almost 50 percent of the Earth's total land area and now threatens to cause the greatest extinction of species seen in the last 65 million years.
Trees Grow Faster With More Carbon Dioxide
If atmospheric CO2 increases as expected, trees will absorb more of the greenhouse gas and grow faster. But that can't prevent global warming, scientists say.
Antarctic Summit on Fishing, Environment, Tourism
Delegates from 24 nations met for the first time ever at Antarctica in January, 1999 to discuss a wide range of issues affecting the ice continent.
|
|
