Ozone Layer Depletion Has Been Halted

An image of the ozone hole above Antarctica in 2010, as recorded by NASA's daily Ozone Hole Watch survey. Credit: NASA/Ozone Hole Watch

From Cosmos:

GENEVA: The protective ozone layer in the Earth's upper atmosphere has stopped thinning and should largely be restored by mid century thanks to a ban on harmful chemicals, U.N. scientists said.

The "Scientific Assessment of Ozone Depletion 2010" report said a 1987 international treaty that phased out chlorofluorocarbons (CFC) - substances used in refrigerators, aerosol sprays and some packing foams - had been successful.

Read more ....

Save the Ozone Layer, Give Global Warming A Boost?

Image courtesy NASA Earth Observatory

From The National Geographic:

While most of the world has warmed, parts of the southern hemisphere have remained stubbornly cold—oddly enough because of a gaping hole in the ozone layer. Now new research shows that all the efforts made by scientists and environmental advocates to close the hole may actually increase warming throughout the entire southern hemisphere.

That's because, for decades, brighter summertime clouds, created by the hole, have reflected more of the sun's rays, acting as a shield against global warming.

Read more ....

Ozone Hole Healing Could Cause Further Climate Warming

Total Antarctic ozone - September 2009. (Credit: NOAA)

From Science Daily:

Science Daily (Jan. 26, 2010) — The hole in the ozone layer is now steadily closing, but its repair could actually increase warming in the southern hemisphere, according to scientists at the University of Leeds.

The Antarctic ozone hole was once regarded as one of the biggest environmental threats, but the discovery of a previously undiscovered feedback shows that it has instead helped to shield this region from carbon-induced warming over the past two decades.

Read more ....

Sea Ice Spread Linked To Ozone Layer

Image From Watts Up With That?

From The Australian:

SEA ice around Antarctica has been increasing at a rate of 100,000sq km a decade since the 1970s, according to a landmark study to be published today.

The study by the British Antarctic Survey, published in the journal Geophysical Research Letters, says rather than melting as a result of global warming, Antarctica continues to expand.

The fact that Antarctic ice is still growing does not in itself prove that global warming is not happening. But the BAS says increased ice formation can be explained by another environmental concern, the hole in the ozone layer, which is affecting local weather conditions.

Read more ....

Why Antarctic Ice Is Growing Despite Global Warming

Photo: Sea ice has grown in the Ross Sea off Antarctica, despite global warming: what's going on? (Image: Daisy Gilardini / The Image Bank / Getty)

From The New Scientist:

It's the southern ozone hole whatdunit. That's why Antarctic sea ice is growing while at the other pole, Arctic ice is shrinking at record rates. It seems CFCs and other ozone-depleting chemicals have given the South Pole respite from global warming.

But only temporarily. According to John Turner of the British Antarctic Survey, the effect will last roughly another decade before Antarctic sea ice starts to decline as well.

Arctic sea ice is decreasing dramatically and reached a record low in 2007. But satellite images studied by Turner and his colleagues show that Antarctic sea ice is increasing in every month of the year expect January. "By the end of the century we expect one third of Antarctic sea ice to disappear," says Turner. "So we're trying to understand why it's increasing now, at a time of global warming."

Read more ....

(Photo from Wikimedia)

Ozone Hole Grows In 2008 -- CNN

(CNN) -- The ozone hole over Antarctica in 2008 is larger in both size and ozone loss than last year, but not as large as in 2006, the European Space Agency said Tuesday.

The hole is a thinning area in the ozone layer over Antarctica and the size of the hole varies every year depending on weather conditions.

This year, the size of the thinned area reached about 27 million square kilometers (10.4 million square miles), compared to 25 million square kilometers (9.65 million square miles) in 2007.

In 2006, the hole was a record 29 million square kilometers (11.2 million square miles), larger than North America, the ESA said.

The ESA announced its results based on information from German and Dutch researchers who analyzed satellite data.

Depletion of ozone is caused by extreme cold temperatures at high altitude and the presence of ozone-destroying gases, such as chlorine and bromine, in the atmosphere, the ESA said.

Those gases originate from man-made products like chlorofluorocarbons, or CFCs, which were phased out under a global agreement two decades ago but continue to linger in the atmosphere.

Ozone is a protective atmospheric layer found at an altitude of about 25 kilometers (15.5 miles).

It acts as a sunlight filter, shielding life on Earth from harmful ultraviolet rays that put humans at greater risk of skin cancer and cataracts and harm marine life, the agency said.

Read more ....