12 October 2005Inter Press Service News Agency
Climate change, which the scientific community links to the increased intensity of tropical storms and other extreme weather phenomena, is also making itself felt in Antarctica, where the "hole" in the ozone layer continues to grow and the increasing break-up of the ice shelves could have played a role in the recent deaths of Argentine and Chilean scientists and members of the military. "The hole in the ozone layer expanded this year, and the quantity of ozone destroyed within that area increased as well," Bedrich Magas, a researcher with the University of Magallanes, told IPS from the city of Punta Arenas. Magas carries out daily measurements of ultraviolet radiation in the port city of 120,000, located at the southern tip of Chile. According to the Argentine Antarctic Institute, in September - the start of the southern hemisphere spring - the hole in the ozone layer reached 28 million square kilometres, representing an eight percent increase from 2004. In addition, the ozone value dropped from 95 to 87 Dobson Units (a measure of the "thickness" of the ozone layer, with 220 units considered the acceptable lower limit). In satellite images, the hole appears as a fluctuating oval-shaped area that in the most critical period - which peaks in September and October - stretches from Antarctica to the southern part of South America, affecting cities in southern Argentina and Chile like Punta Arenas, 1,000 km north of the Antarctic's King George Island and 2,300 km south of Santiago. The ozone layer protects the earth from the harmful effects of ultraviolet radiation, which include skin cancer and cataracts in humans and threats to flora and fauna. Claudio Casiccia, a physicist who heads the Ozone Laboratory at the University of Magallanes, told IPS that in early October, the hole shrank to 21 million square kilometres, from 24 million square kilometres in August and 28 million square kilometres in September. Nevertheless, the ozone value has remained below 100 Dobson Units. "The southern portion of South America, Patagonia and the Magallanes region, are under the influence of the Antarctic ozone hole for a short period in springtime, with varying thickness and intensity. This year, we had an event (in Punta Arenas), but there was no major increase in ultraviolet radiation, because the angle of the sun is still steep and it is quite cloudy," said the scientist. The thinning of the ozone layer is blamed on chemical emissions like halons, which are used in fire extinguishers, CFCs (chlorofluorocarbons), used in refrigerators, air conditioners and aerosols, and methyl bromide, used as a pesticide and in building fumigations. The Montreal Protocol, signed in 1987, set global targets for phasing out these chemicals, which "according to estimates by scientists will allow the ozone layer to recover by the middle of this century," Ana Isabel Zúñiga, head of the governmental National Environment Commission's Ozone Programme in Chile, told IPS. But the scientific community itself has warned that the greenhouse effect, caused by carbon dioxide (CO2) and other emissions from the burning of fossil fuels blamed for global warming, is also having an impact on the thinning of the ozone layer. The Kyoto Protocol, aimed at cutting emissions of greenhouse gases - which has not been signed by the United States, the largest single source of these gases - should thus act along with the Montreal Protocol to protect the ozone layer, while it curbs other phenomena attributed to global warming. Attention has been focused lately on devastating hurricanes like Katrina and Stan, because studies have shown that warmer oceans and rising sea levels are producing stronger tropical storms, said Vicki Arroyo, director of policy analysis for the Virginia-based Pew Centre on Global Climate Change. Another U.S. scientist, Peter Frumhoff with the Global Environment Programme of the Union of Concerned Scientists, told IPS in late September that "The recent science has clearly linked higher storm intensity to climate change." The phenomenon of climate change was also blamed for the drought, high temperatures and flooding seen in Europe since 2002. Casiccia said that while the link between global warming and extreme weather events is still being studied, "it has been accepted that there is an important relationship, in need of further study, between the weakening of the ozone layer and global climate change." Paola Vasconi, coordinator of the Santiago-based Terram Foundation's environment programme, told IPS that the increase in ultraviolet radiation also drives up temperatures. "One thing is probably certain: if the climate does not stabilise, the hole in the ozone layer will never close," said Magas, who pointed out that the United States emits "the shocking equivalent of 25 tons of CO2 per capita every year, compared to 3.7 tons for Chile and a global average of three tons per capita." The link between global warming and the thinning of the ozone layer was demonstrated in 1987 by international measurements taken in the Magallanes region, the scientist pointed out. "The incredible thing is that after that, efforts were not undertaken to curb emissions of greenhouse gases, which are today, now that CFC emissions have been curtailed, the main cause of the destruction of ozone worldwide," said Magas. "Although it sounds terrible, the hurricanes are welcome, if that's what it takes to change the mentality of the big, irresponsible polluters," he added. U.S. "President (George W.) Bush issued a call to 'drive less' and announced a federal programme aimed at cutting fuel consumption - accompanied, of course, by deregulation policies on the environment allowing for increased exploration and drilling for oil in protected wilderness areas," said Magas. On Sept. 16, International Day for the Preservation of the Ozone Layer, United Nations Secretary-General Kofi Annan underscored the efforts made by the international community to curb the use of ozone-depleting substances. The next day, two Argentine men lost their lives in Antarctica - biologist Augusto Thibaud and naval officer Teófilo González - when their snowmobile plunged into a deep hidden crevasse. And on Sep. 28, Captain Enrique Encina and non-commissioned officers Fernando Burboa and Jorge Basualto, members of the Chilean army, died when their snow-cat fell into a 40-metre crevasse in Antarctica. Magas pointed out that although there have always been crevasses on that continent, making travel dangerous, the ice shelves are increasingly breaking up due to the higher temperatures associated with global warming. With a surface area of more than 14 million square kilometres, Antarctica is the fourth-largest continent. A full 95 percent of the territory is ice, and the continent accounts for 70 percent of the world's fresh water reserves.
