Hi Ozone Layer Healing, But...
According to the ozone sensors on Europe's MetOpt weather satellite, the hole over Antarctica in 2012 was the smallest in the last 10 years.
Since the beginning of the 1980s, an ozone hole has developed over Antarctica during the southern spring - September to November - resulting in a decrease in ozone concentration of up to 70%.
Man-made chlorofluorocarbons - CFCs - have a negative effect on the ozone, depleting it and creating the infamous hole.
The Montreal Protocol has stopped the increase of CFC concentrations, and a drastic fall has been observed since the mid-1990s.
You can see the Total Ozone values in the Northern Hemishpere and Southern Hemisphere along with the climate model prediction (in blue) showing recovery continuing over several decades.
The bad news is that scientists now think it is helping to slow the polar seas' ability to absorb carbon dioxide, a leading contributor to Global Warming.
Antarctic accounts for about 40% of the total carbon absorbed by the world's seas.
Scientists at Johns Hopkins University found the same winds that caused extremely low temperatures leading to higher levels of ozone depletion are speeding circulation patterns in polar waters, with the currents closer to the land pushing more deep water up to the ocean surface.
Scientists worry that the increasing upwelling of that water, hundreds of years old and naturally rich in carbon dioxide, is reducing the amount of manmade carbon absorbed by sub-polar waters.
Thanks to the Montreal Protocol we are well on our way to eliminating the use of CFCs.
The damage however will go on for decades and more.
Further information on these most recent studies can be found in the Feb 15, 2013 issue of OzoNews click the following link here to download.
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