why the hole in the ozone layer over antarctica
bromine chlorine methyl bromide CFCs halons
title: Antarctica text: Earth. Antarctic ice serves as both the shield and the detection medium for the largest neutrino telescope in the world, built below Amundsen–Scott station. Since the 1970s an important focus of study has been the ozone layer in the atmosphere above Antarctica. In 1985, three British scientists working on data they had gathered at Halley Station on the Brunt Ice Shelf discovered the existence of a hole in this layer. It was eventually determined that the destruction of the ozone was caused by chlorofluorocarbons (CFCs) emitted by human products. With the ban of CFCs in the Montreal Protocol of 1989, title: Ozone depletion text: widely reported in the press. The especially rapid ozone depletion in Antarctica had previously been dismissed as a measurement error. Scientific consensus was established after regulation. While the Antarctic ozone hole has a relatively small effect on global ozone, the hole has generated a great deal of public interest because: Since the ozone layer absorbs UVB ultraviolet light from the sun, ozone layer depletion increases surface UVB levels (all else equal), which could lead to damage, including increase in skin cancer. This was the reason for the Montreal Protocol. Although decreases in stratospheric ozone are well-tied to CFCs and to title: Antarctica text: detected by scientists in 1985 and has tended to increase over the years of observation. The ozone hole is attributed to the emission of chlorofluorocarbons or CFCs into the atmosphere, which decompose the ozone into other gases. Some scientific studies suggest that ozone depletion may have a dominant role in governing climatic change in Antarctica (and a wider area of the Southern Hemisphere). Ozone absorbs large amounts of ultraviolet radiation in the stratosphere. Ozone depletion over Antarctica can cause a cooling of around 6 °C in the local stratosphere. This cooling has the effect of intensifying the westerly winds which title: Ozone layer text: of April and May and lowest in October. While the total amount of ozone increases moving from the tropics to higher latitudes, the concentrations are greater in high northern latitudes than in high southern latitudes, due to the ozone hole phenomenon. The highest amounts of ozone are found over the Arctic during the spring months of March and April, but the Antarctic has their lowest amounts of ozone during their summer months of September and October, The ozone layer can be depleted by free radical catalysts, including nitric oxide (NO), nitrous oxide (NO), hydroxyl (OH), atomic chlorine (Cl), and atomic title: British Antarctic Survey text: last 10,000 years, the volcanic ash was found deposited on the ice surface under the Hudson Mountains, close to Pine Island Glacier. The British Antarctic Survey were also responsible for the discovery of the hole in the ozone layer over Antarctica. The discovery was made in 1985 by a team of three BAS scientists: Joe Farman, Brian Gardiner and Jonathan Shanklin. Their work was confirmed by satellite data, and was met with worldwide concern. The BAS runs an online polar image collection which includes imagery of scientific research at the poles, logistics operations, and the continent and its wildlife. The