The hole in the ozone layer over Antarctica is approaching record size, and this indicates that 20 years of efforts against ozone-depleting substances have not had the desired effect, says the UN.
The ozone layer is destroyed by ozone-depleting substances such as SF6, CFCs and related substances that have been used in refrigerators, air conditioning and cleaning. The Montreal Protocol was signed in 1987 to stop the emissions of these substances.
The 189 countries that have ratified the protocol have contributed to preventing more than 1.5 million tonnes of CFC substances from escaping into the atmosphere, but there are still substances that need to be taken care of, says UN Secretary-General Kofi Annan. - But the developing countries are only halfway through their obligations, he says. Geir Braathen, who is the ozone expert at the World Meteorological Organization (WMO), says that the ozone hole is 27 million square kilometers, and that it is expected to increase by another square kilometer.
This is not enough to set a new record, but it shows that the work to stop the depletion of the ozone layer has not been completed. - The rebuilding of the ozone layer cannot currently be demonstrated, he says. American scientists reported last month that the depletion of the ozone layer appears to have stopped, but that it will take several decades before it is rebuilt.
The breakdown of the ozone layer causes more ultraviolet radiation to reach the earth, and this leads to an increased frequency of skin cancer. It will also have an effect on a number of organisms other than humans. There is significantly higher UV radiation in southern parts of Argentina now, due to this hole in the ozone layer.