BBC Focus Magazine

[Shadowwolf]

The Antarctic ozone hole, which yawns wide every Southern Hemisphere spring, reached its annual peak on September 12, stretching 10.05 million square miles, the ninth largest on record. Above the South Pole, the ozone hole reached its deepest point of the season on October 9 when total ozone readings dropped to 102 Dobson units, tied for the 10th lowest in the 26-year record.

The ozone layer helps protect the planet's surface from harmful ultraviolet radiation. NOAA and NASA use balloon-borne instruments, ground instruments, and satellites to monitor the annual South Pole ozone hole, global levels of ozone in the stratosphere, and the human-made chemicals that contribute to ozone depletion.

http://www.sciencedaily.com/releases/2011/10/111020145106.htm

[M Paul Lloyd]

So, just giving up CFC's really wasn't enough after all.

[Healerman]

I think it was said that it would take several decades for CFCs to be degraded out of the system. It also took time to phase out CFCs, and not all countries got on board all at once. If I recall, it was something like 2040 or 2050 before the ozone layer is expected to be recovered from our unwitting interference.

[M Paul Lloyd]

So we wait I guess.

I have to ask but does anyone happen to know if the ozone layer has been depleted in other parts of the world rather than just this huge area over Antarctica? Its just that for all we had a pretty poor summer here in the UK when the sun did shine it seemed cruelly intense at times and I have since learned that solar UV levels were higher than expected?

[KingPhillip]

On October 2nd, BBC's Richard Black reported the Arctic ozone had set a record low. I remembered reading it then and was surprised the Antarctic news reached this forum first.

Back when, CFC's were the primary suspects chemistry-wise. Now, the short- and long-term fluctuations of ozone levels are explained with a systemic approach. Not enough to exculpate the CFC's.

[Flakkarin]

The hole is primarily focused over the Antarctic because of the encircling winds: the location of the continent surrounded by oceans leads to intense pooling of CFCs. The Arctic is less isolated than that, so the effect is less, but still...