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OZONE HOLE INFLUENCES SOUTHERN CHILE & ARGENTINA On the 9th October the town of Punta Arenas in Southern Chile and neighbouring Ushuaia in Argentina became the significantly populated areas to be affected by the Antarctic ozone hole. Ultraviolet radiation levels rose to significant highs after the ozone hole widened to cover the southern tip of South America. Local health authorities urged residents to use protection whilst outside, since the high levels of ultraviolet radiation could cause skin burns within seven minutes. Source: MSNBC News: Cities see radiation alert over ozone.
According to NASA, this year's ozone hole over the Antarctic is the largest ever. The Antarctic ozone hole forms each year between August and October, before dissipating again when air temperatures increase during the Southern Hemisphere summer months. On the 3rd September the ozone hole measured over 28 million square kilometres, larger than the area of the United States. The previous record occurred 2 years ago, with the hole then measuring 27.2 million square kilometres. Measurements of ozone above Antarctica are taken by the Total Ozone Mapping Spectrometer (TOMS) instrument. Ozone hole images provided by TOMS are available on the Internet at: http://toms.gsfc.nasa.gov. Source: Global Environmental Change Report, 22nd September 2000.
RECORD ARCTIC OZONE LOSS? Throughout the 1990s new records for polar stratospheric ozone depletion were regularly set. Although there are now signs that regulation of ozone depletion chemicals under the Montreal Protocol is now having a beneficial effect, the New Scientist has reported that this year's record low Arctic temperatures could create the largest ozone hole in the Northern Hemisphere to date. Ozone holes have been more commonly associated with the Antarctic, where upper atmospheric temperatures are usually lower. At temperatures of less than -78°C, the presence of polar stratospheric clouds speeds up the destruction of ozone. This year, temperatures above the Arctic have been consistently low, with polar stratospheric clouds forming since November 1999. There are fears that global warming may enhance the loss of ozone above the Arctic, as trapped radiation in the lower atmosphere (causing surface warming) will lead to further cooling of the stratosphere. Source: Global Environmental Change Report, January 28th 2000; New Scientist, no. 2222, 22nd January 2000. Main menu | Home
MONTREAL PROTOCOL GAINS NEW BEIJING AMENDMENT The Montreal Protocol added a new amendment to its list during the recent proceedings in China. The new Beijing amendment has put in motion several changes. Chlorobromomethene has been added to the list of controlled, ozone depleting chemicals. Production controls on hydrochlorfluorocarbons (HCFCs) have been set for 2004, along with a ban on trade with nations not supporting the Copenhagen amendment. All countries must phase out the consumption and production of bromochloromethane by 2002. The amendment has finally added the requirement that parties report annually on their use of methyl bromide for quarantine and preshipment purposes. As long as that at least 20 of the member parties ratifies the amendment, it will enter force on 1 January 2001. Aside from the amendment, negotiators have also adopted a Beijing declaration to reaffirm parties’ ‘commitment to the protection of the ozone layer’, urging industrial nations to reduce the transfer of ozone depleting substances to developing nations. More information is available from the UN Environmental Programme’s Ozone Secretariat webpage: http://www.unep.org/ozone/home.htm Source: Global Environmental Change Report, 10 December. Main menu | Home
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OZONE DEPLETION ISSUES |