|
10
de diciembre del 2000
|
||||
![]() |
![]() |
![]() |
||
|
|
|
|||
|
The latest satellite measurements, according to the Nairobi-based UN agency, reveal that the stratospheric "hole" over the Antarctic had reached a record 28.3 million square km in September. The figure exceeds the previous record - from 1998 - by at least a million square km, despite progress made in global efforts to phase out the use of chlorofluorocarbons (CFCs) and other chemicals responsible for ozone depletion. Reports earlier this year indicated that ozone depletion over the earth's northern latitudes had also reached record levels, leading to predictions of a second ozone hole over the Arctic. "While enormous progress has been made over the past decade in phasing out ozone destroying chemicals, the health of the ozone layer remains critical," notes Dr. Klaus Toepfer who heads the UNEP, which spearheaded the adoption of the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987. "Our key task for the next decade, and for the meeting here in Ouagadougou, is to complete the efforts of the previous decade to ensure that developing countries have the financial and technological resources they need to make full transition to ozone -friendly economies." The delegates at the conference will review 1999 data reports on CFCs from developing countries, which the Montreal Protocol stipulates must now begin to accelerate phase-out to achieve a 50 percent cut by 2005. The deadline for a complete phase-out of CFCs is 2010. Industrialized countries have met their deadlines, while developing countries enjoyed a ten-year grace period before they began making cuts in their CFCs, halons, and carbon tetrachloride emissions to average 1995 levels by July 1, 1999. The depletion of the ozone layer is believed to allow more of the ultraviolet B radiation to reach the earth's surface, with potentially harmful effects on human and animal health, on plants, aquatic life and even on plastics. Excessive UV-B radiation can lead to skin cancer, eye cataracts and loss of physical immunity in humans. ''The warming of the atmosphere near the ground causes the stratosphere to become even cooler, and cold stratospheric temperatures, particularly during early Antarctic spring, catalyze the chemical processes that destroy ozone molecules,'' says a new UNEP study. The
Scientific Assessment Panel of the Montreal Protocol, projects that the
ozone layer could recover to pre-1980 levels by 2050, but only if the
Montreal protocol is implemented to the letter, and all countries phase
out the use of CFCs. Copyright © 2000 Tierramérica. Todos los Derechos Reservados |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||