Feeds

This year's ozone hole set to be a whopper

Penguins rush to buy suncream

Intelligent flash storage arrays

The hole in the Ozone layer over Antarctica this year is shaping up to be one of the biggest ever, satellite images from the European Space Agency (ESA) suggest.

The area of depletion, as the scientists call it, already covers ten million square kilometres, is still expanding, and won't reach its maximum until some time in September. Only the holes in 1996 and 2000 were larger at this stage in their development, ESA says.

The Ozone layer naturally fluctuates through the year, reaching its peak thickness in the summer months and fading away during the winter. Regional variations in weather systems play a part in the timing of the hole's appearance, ESA explains.

During the southern hemisphere winter, the prevailing winds in Antarctica, known as the polar vortex, keep the atmospheric mass above the Antarctic continent is isolated from exchanges with mid-latitude air.

This keeps the air mass above the continent cold, and in the cold and dark, clouds that contain chlorine can form in the polar stratosphere.

Once the spring returns, this chlorine, much of it originating from man-made pollutants like chlorofluorocarbons, disrupts the ozone layer.

The sunlight splits the chlorine into highly reactive ions that break ozone down into normal oxygen molecules. One molecule of chlorine can break down thousands of ozone molecules.

However, use of CFCs has decreased significantly since the 1987 Montreal Protocol, and there is evidence that the protective atmospheric layer is beginning to recover from the damage wrought. A full recovery is not expected before 2050. ®

Providing a secure and efficient Helpdesk

More from The Register

next story
GRAV WAVE DRAMA: 'Big Bang echo' may have been grit on the scanner – boffins
Exit Planet Dust on faster-than-light expansion of universe
Mine Bitcoins with PENCIL and PAPER
Forget Sudoku, crunch SHA-256 algos
SpaceX Dragon cargo truck flies 3D printer to ISS: Clawdown in 3, 2...
Craft berths at space station with supplies, experiments, toys
NASA rover Curiosity drills HOLE in MARS 'GOLF COURSE'
Joins 'traffic light' and perfect stony sphere on the Red Planet
'This BITE MARK is a SMOKING GUN': Boffins probe ancient assault
Tooth embedded in thigh bone may tell who pulled the trigger
Big dinosaur wowed females with its ENORMOUS HOOTER
That's right, Doris, I've got biggest snout in the prehistoric world
DOLPHINS SMELL MAGNETS – did we hear that right, boffins?
Xavier's School for Gifted Magnetotaceans
Japanese volcano eruption reportedly leaves 31 people presumed dead
Hopes fade of finding survivors on Mount Ontake
That glass of water you just drank? It was OLDER than the SUN
One MEELLION years older. Some of it anyway
prev story

Whitepapers

A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.