- GENEVA (Reuters) - The earth's protective ozone layer will hit its all-time
thinnest by 2000 or 2001, the World Meteorological Organization said Monday.
- Despite forecasts that international
measures to halt the decline will help the layer improve by the middle
of the next century, the ozone layer is at its most vulnerable now and
things will get worse before they get any better, the WMO said.
- "We could expect this ozone depletion
to be stronger than anything we have observed up to now," Rumen Bojkov,
the leading ozone expert at the Geneva-based U.N. weather agency, told
a news conference.
- The ozone layer is a protective fragile
shield of gas that absorbs harmful ultraviolet rays of the sun but has
been increasingly pierced by
- holes caused by man-made chemicals. The
holes are blamed for causing skin cancer and cataracts.
- Bojkov said the holes were forecast to
stay for the coming 20 years before a recovery by the middle of the next
century brings it back to the 1960s levels, according to scientific models.
- But he said detecting any such recovery
would take at least another 20 years because of scientific limitations.
- The WMO also said its research showed
that the role of the chemical methyl bromide as an ozone-depleting substance
was less than previously thought. The fumigant used in agriculture was
seen as the most important ozone-depleting chemical used worldwide.
- It called on countries of the world to
implement measures agreed by the 1987 Montreal Protocol -- an international
agreement on limiting substances that deplete the ozone layer.
- Under that agreement, developed and developing
countries agreed to phase out CFCs -- chlorofluorocarbons which are commonly
used in aerosols and refrigeration systems. Many experts doubt the targets
can be met, although CFC use has dropped dramatically in many industrialized