Image credit: theozonehole.com

Southern hemisphere spring, that is.

European weather scientists believe the ozone hole over the Antarctic this spring may be one of the smallest since the mid-1980s, says stuff(NZ).

Experts at the Copernicus Atmosphere Monitoring Service (CAMS) have observed strange behaviours of the annual ozone hole this season.

Not only is it already shrinking and well on the way to being about half the size it usually is at this time of year, but also it began forming about two weeks earlier than usual and it is off-centre, away from the South Pole.

They say that is probably the result of the rare sudden stratospheric warming, which has been under way about 30km above Antarctica since last month.

Ozone in the stratosphere – the second tier of the atmosphere – absorbs the Sun’s damaging ultra-violet (UV) radiation. But ozone depletion causes a rise in UV radiation at the surface and a higher risk of skin cancers.

New Zealand has the highest skin cancer rate in the world, according to the Ministry of Health, with about 82,000 new skin cancers confirmed annually.

CAMS head Vincent-Henri Peuch​ said the Antarctic ozone hole typically started to form every year in August, reaching a maximum size in October and finally closing again in December.

“Since early September, the polar vortex which provides the conditions for ozone hole formation has been displaced off-centre and weakened by a sudden stratospheric warming event. With temperatures in the upper stratosphere rising up to 40 degrees Celsius above normal, the polar vortex has been more unstable than normal.”

Full report here.

via Tallbloke’s Talkshop

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September 17, 2019 at 02:43AM