September 16, 2009

UN Agency Says Hole In Ozone Is Smaller Than In 2008

Experts say the hole in the ozone is expected to be smaller in 2009 than it was a year ago, AFP reported.

The World Meteorological Organization reported on Wednesday that conditions observed so far could indicate that the 2009 ozone hole will be smaller than those of 2006 and 2008 and close to that of 2007.

The UN agency discovered the hole over the Antarctic in the 1980s. Experts there said it regularly tends to form in August, reaching a maximum size by late September or early October before it fills again in December.

Weather conditions play a large role in the size of the hole.

Geir Braathen, the WMO's expert on the ozone, said this year the hole began forming earlier than before and on September 16 it stood at 10 million square miles.

The maximum reached was 10 million square miles in 2008, while in 2007 the maximum was 9 million square miles.

However, the damage to the ozone layer, which shields the Earth from harmful ultra-violet rays, is so bad that it will only attain full recovery in 2075, experts warned.

The ozone provides a natural protective filter against the sun's harmful ultra-violet rays, which can damage vegetation as well as cause sunburn, cataracts and skin cancer.

Extreme cold at high altitude and a particular type of pollution, from chemicals often used in refrigeration, have contributed to the layers depletion.

Some plastic foams, or aerosol sprays, which have accumulated in the atmosphere, also add to the ozone's destruction.

The 1987 Montreal Protocol is currently phasing out most of these chemicals, known as chlorofluorocarbons (CFCs), but they can linger in the atmosphere for decades.


Image Caption: Image of the largest Antarctic ozone hole ever recorded (September 2006). NASA


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