SYDNEY, September 17 (IslamOnline & News Agencies) - The hole in the ozone layer over Antarctica that protects life on earth from the sun's ultra-violet rays is shrinking and will be closed by 2050, an Australian scientific team forecast Tuesday, news agencies reported.

The team has discovered the level of ozone-eating chlorine from chlorofluorocarbons (CFCs) in the atmosphere has begun to fall some 30 years after the hole was first detected, reported Agence France-Presse (AFP).

At its peak, the hole was three times the size of Australia. But Paul Fraser, chief atmospheric researcher with Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO), said a ban imposed on CFCs in the 1990s under the Montreal Protocol had begun paying off. "This is big news, we have been waiting for this," he said.

Research by a monitoring station run jointly by the CSIRO and the Bureau of Meteorology at Cape Grim in Tasmania found that the chlorine leveled off in 2000 and had started to fall for the first time.

Fraser said the research had proved the CFCs, which he described as "the major culprit" in the erosion of the ozone level, were declining along with some other lesser ozone depleting chemicals.

"There has been some suggestion that, for example, the greenhouse effect, climate change, may change our prediction about when the ozone hole might close," he said. "But on balance, people think that the ozone hole will have recovered by about 2050."

Fraser is the co-author of a report just released by the UN and the World Meteorological Organization which found the total level of ozone-damaging chemicals was already falling and that upper levels had probably peaked.

The latest findings by the Cape Grim station came too late to be included in the report.

CFC levels rose from zero in 1950 to 2.1 parts per billion by 1995 and peaked at about 2.15 parts per billion in 2000, largely because of the effect of old refrigerators and car air-conditioners which used CFCs.

Developed in the 1930s as a domestic refrigerant, CFCs were added as propellants to spray cans issued to U.S. troops in World War II. Then they came into widespread use in refrigerators, air conditioners and fire extinguishers.

Fraser said the successful global effort to save the ozone should give a boost to current efforts under the so-called Kyoto Protocol to curb production of greenhouse gases which cause global warming.

"I think this shows global protocols can work," he said, while acknowledging that "the economics" of greenhouse gases were far more complex than the CFC issue.

An environmental group, the Australian Conservation Foundation, said the latest forecast about the hole in the ozone layer was proof of the need for Australia to sign the Kyoto Protocol on climate change, which it has refused so far to do.

"It shows that when the international community comes together and signs a strong protocol, as they did over 10 years ago for ozone, that we really can fix big problems harming our whole atmosphere," said ACF executive director of Don Henry.

Meanwhile, on Monday, September 16, scientists in Paris said that efforts to repair the damaged ozone layer are proceeding well but the earth's wafer-thin stratospheric shield will remain vulnerable for the next decade or so.

In a rare bit of good news about global environmental problems, they said the world was steadily heading towards the goals of the Montreal Protocol, the 1987 UN treaty that committed signatories to phasing out chlorine-based chemicals that erode the ozone layer.

"These results confirm that the Montreal Protocol is achieving its objectives. During the next decades, we should see a recovery of the ozone layer," said Gerard Megie, co-chair of the international scientific assessment panel that delivered its executive summary in Paris on Monday.

"However, the concentration of chlorine in the stratosphere has now reached a maximum and the ozone layer is still quite vulnerable," Megie said in a statement.

"It is therefore extremely important that the control measures in the Montreal Protocol are strictly respected by all."

The panel's full report -- the latest in a series of evaluations which are published every four years -- will be handed shortly to the UN Environment Program (UNEP) and World Meteorological Organization (WMO). Around 250 scientists took part in its compilation.

In other findings, the scientists said an emerging ozone hole over the North Pole, which was first detected more than two years ago, was unlikely to be as bad as the one over Antarctica.

The Antarctica hole has increased in size in the past decade but not as rapidly as in the 1980s, they said.

"It is not yet possible to say whether the area of the ozone hole has maximized... (but) a future Arctic polar ozone hole similar to the size of the Antarctic appears unlikely."

But they warned there were many unknowns about the possible link between the ozone hole and global warming, the phenomenon caused by greenhouse gases that trap the sun's heat and gradually cause the earth's atmosphere to warm.

Growing evidence suggests that hydro fluorocarbons (HFCs) - the substances that are being used as transitional substitutes for chlorofluorocarbons (CFCs) - could contribute to global warming, they said.

Under the Montreal Protocol, which has been ratified by 183 countries, industrialized countries were scheduled to have scrapped ozone-depleting chemicals by 2000 and developing countries were given another decade to achieve that goal.

The U.N. Environmental Program and World Meteorological Organization said, Monday, that there was little risk of an "ozone hole" developing over the Arctic similar to the one detected over the Antarctic.

The "world is making steady progress toward the recovery of the ozone layer ... with the total amount of ozone-depleting chemicals in the lower atmosphere continuing to decline, albeit slowly," the statement said.

This, however, was more reason to work toward further emission reductions that are harmful to the ozone layer, said Klaus Toepfer, UNEP executive director. "We must not be complacent," Toepfer said.

U.N. Secretary-General Kofi Annan urged all countries to contribute toward reducing the emissions.