World Bulletin/News Desk
The hole in the ozone layer, the earth's protective shield against ultraviolet rays, is expected to be smaller this year over the Antarctic than last, showing how a ban on harmful substances has stopped its depletion, the United Nations said on Friday.
But the hole is probably larger than in 2010 and a complete recovery is still a long way off.
The signing of the Montreal Protocol 25 years ago to phase out chemicals that deplete the ozone layer has helped prevent millions of cases of skin cancer and eye cataracts as well as harmful effects on the environment, the U.N. weather agency said.
"The temperature conditions and the extent of polar stratospheric clouds so far this year indicate that the degree of ozone loss will be smaller than in 2011 but probably somewhat larger than in 2010," the World Meteorological Organization (WMO) said in a statement.
The Antarctic ozone hole, which currently measures 19 million square kilometres, most likely would be smaller this year than in the record year of 2006, it said. The annual occurrence typically reaches its maximum surface area during late September and maximum depth in early October.
But the banned chlorofluorocarbons (CFCs), once used in refrigerators and spray cans, have a long lifetime in the atmosphere and it will take several decades before their concentrations are back to pre-1980 levels, the WMO said.
The Montreal protocol has been a "great success", U.N. weather agency expert Geir Braathen told a news briefing.
"This has prevented a major environmental disaster and globally ozone depletion has levelled off. We haven't really seen any kind of unequivocal ozone recovery yet," he said.
"Ozone depletion has stopped, levelled off," Braathen said.
In the Arctic stratosphere, there was record ozone loss in spring of 2011, but it has returned to more normal conditions this year, he said.
Administrator touts success in planetary study, deep-space experiments, aviation innovation
A man left brain-dead after an experimental drug trial in France has died, local media report.
Facebook founder to donate majority of fortune over lifetime to newly formed charity
Facebook will appeal a date privacy ruling in Belgium that forces the social media giant to stop collecting digital information about people who are non-members
Japanese, Chinese, Irish scientists win 2015 Nobel prize in medicine for malaria and parasite research
Discovery could have major implications for pursuit of life on the red planet
Lawsuit sheds light on no poaching policy at Silicon Valley’s biggest companies
Searches for oncoming storms will display information such as maps, forecasts, reminders and preparedness instructions
New service unveiled as survey finds Americans having hard time navigating smartphone etiquette
Turkcell, Vodafone and Avea bid total of over €1.14 billion for the right to use frequencies on the new network
Petition 'will present at least two substantial questions concerning design-patent liability and damages'
The Istanbul Electric Tram and Tunnel Company plans to launch one solar-powered bus on Thursday and several more in the coming days
Roughly 70 million tonnes of fibres are traded globally per year, but nearly two thirds are made from non-renewable products like petroleum and natural gas.
Researchers havfe said that the flaw leaves data stored by apps vulnerable with almost every category of app considered vulnerable
SpaceX revealed Monday that it is building a test track for the Hyperloop, a concept for ultra-fast ground transport the company’s CEO, Elon Musk, unveiled.
Biologists have created chicken embryos with dinosaur-like faces by tinkering with the molecules that build the birds' beaks.