The Antarctic ozone hole in 2012 was the smallest in 10 years

Area of the ozone hole over Antarctica, which in September reached its maximum size, this year was 21.2 million square kilometers — its lowest level since 2002, according to NASA.

The ozone layer — a natural shield that protects the Earth's surface from ultraviolet radiation hard, dangerous to living organisms. The sharp drop in the concentration of stratospheric ozone during the winter season was first discovered over Antarctica in 1980. According to modern concepts, the destruction of ozone (triatomic molecules of oxygen) due to the impact of chlorofluorocarbons (CFC), which at low temperatures trigger the reaction of their decay. Each winter, the Antarctic ozone hole is growing, reaching a maximum area in September, and in the summer reduced.

"By reducing the ozone hole has that this year the average temperature in the stratosphere were slightly higher," — said the Goddard Space Flight Center NASA's Goddard Paul Newman (Paul Newman).

He notes that the increase in temperature was due to the natural periodic natural processes unrelated to human activity.

In addition, the scientists noted that within the same "hole" (the site is too thin the ozone layer, which can not hold ultraviolet) ozone concentrations also increased, reaching about 140 Dobson units (used to measure ozone in the atmosphere). The "healthy" atmosphere with normal thickness of the ozone layer, this figure should be from 240 to 500.

Record low ozone hole area in the past 20 years was recorded in September 2002, when the value was 18 million square kilometers.

In September, the specialists of the UN Environment Programme (UNEP) released a report saying that ozone gas stops falling since 1998, and is projected to scientists, to the years 2050-2075 can return to the levels fixed until 1980.

In 2011, a group of Australian scientists published an article which concluded that gradually decrease in size and became a seasonal ozone hole over Antarctica, which, according to their data, from the late 1990s "dragged" by about 15%.

The ozone hole was the "delayed" after the 1987 Montreal Protocol, which limits production and trafficking of substances.

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