A 25-year-old ozone treaty has prevented environmental disaster, a UN scientist said. In the Arctic, record damage was reported in 2011, but levels have normalized in 2012, according to the scientist.
The Montreal Protocol, signed September 16, 1987, has helped prevent further damage to the ozone layer, which filters harmful ultraviolet rays that can contribute to global warming, cause skin cancers and damage vegetation, according to scientists.
The agreement bans ozone-depleting substances like chlorofluorocarbon gases, which were nearly omnipresent in aerosols and refrigerators when the protocol was signed.
"The Montreal Protocol has prevented a major environmental disaster," said Gael Braathen, the World Meteorological Organization's senior scientific officer for atmospheric environment research.
According to WMO figures, the Antarctic's ozone-depleting gases peaked in 2000. The amount has decreased about 1 percent annually and has now leveled off, according to Braathen, who added, however, that complete recovery is still in the distant future.
"As we speak, ozone depletion is going on," Braathen said.
WMO predictions say the ozone will recover to pre-1980 levels outside of polar regions by mid-century. However, it will take much longer for the ozone layer to recover over the Antarctic.
"Ozone-depleting gases have a long lifetime in the atmosphere, so it will take some decades before the ozone is back to where it was in the past," Braathen said.
mkg/mz (AFP, Retuers)