Deepest and largest ever ozone hole keeps Chileans and Argentinians indoors

One of the few areas in the world where people live beneath the hole in the ozone layer is feeling the effects of what the United Nations described as the deepest ozone hole over the Antarctic since records began 15 years ago. Less than one month before the UN’s World Meteorological Organization announcement, detailing more than 50% depletion throughout most of the hole, NASA had identified that this year’s was also the largest ever, at three times bigger than the entire land mass of the US (see related story).

Health authorities in the southern Chilean city of Punta Arenas and neighbouring Ushuaia on Argentina’s side of Tierra del Fuego island have warned both populations numbering about 120,000 each, to avoid the sun during the day, especially between 11am and 3pm. Health authorities in both cities have called an orange alert – the second most dangerous level in a scale of four – in which ultraviolet (UV) exposure can cause skin burns in 7 minutes, and said that if people must leave home they should use sun block, UV protective sunglasses, wide brimmed hats and clothing with long sleeves.

“Normal ozone readings are about 320 Dobson units, but on the worst day so far on Saturday (7 October), we recorded 180 units,” Dr. Claudio Casiccia, head of the ozone department at Punta Arenas’ University of Magallanes told edie. “We are below that level now but the danger is by no means over”, he said.

As yet, there are no reports of how increased effects of ultraviolet radiation could be affecting the area’s wildlife, which contains the famous Torres del Paine and Tierra del Fuego national parks, and is home to whale, seal, walrus, rhea, guanacos and penguin populations.

Every year at this time the ozone hole increases in size, caused in part by low temperatures during the southern hemisphere’s winter, although the “near total destruction” of the ozone in some layers of the stratosphere was observed from mid-September this year, much earlier than normal, according to the WMO. The process accelerates as the region enters spring-time and usually peaks in the first or second week of October.