Ozone layer damaged by unusually harsh winter
The stratospheric ozone layer, which shields the Earth from the Sun's harmful ultraviolet rays, has been damaged to its greatest-ever extent over the Arctic this winter.
The protective layer of gas, which can be destroyed by reactions with industrial chemicals, has suffered a loss of about 40 per cent from the start of winter until late March, exceeding the previous seasonal loss of about 30 per cent, according to the World Meteorological Organisation (WMO).
The phenomenon is annual in the Antarctic, where after its discovery in the 1980s it came to be known as the "ozone hole". Although CFC levels are now dropping, they remain in the atmosphere for so long that they will still be causing ozone depletion for decades in certain conditions, particularly the intense cold of the stratosphere.
Arctic ozone conditions vary more and the temperatures are always warmer than over Antarctica, where the ozone hole forms high in the stratosphere near the South Pole each winter and spring. Because of changing weather and temperatures, some Arctic winters experience almost no ozone loss – but others with exceptionally cold stratospheric conditions can occasionally lead to substantial ozone depletion.
This is what has happened over the Arctic this winter; for while at ground level the Arctic region was unusually warm, temperatures 15-20km above the Earth's surface plummeted. WMO officials say the latest losses, which are unprecedented, were detected in observations from the ground and from balloons and satellites over the Arctic.
"The Arctic stratosphere continues to be vulnerable to ozone destruction caused by ozone-depleting substances linked to human activities," said the WMO's secretary general, Michel Jarraud.
Loss of ozone allows more of the Sun's harmful ultraviolet-B rays to penetrate the atmosphere. They have been linked to increased rates of skin cancer, cataracts and immune system damage.
In late March, winds blew the ozone-depleted region over Greenland and Scandinavia, and the WMO is warning people there to heed national alerts and forecasts of ozone levels. The development is unlikely to be risky for humans as the depleted ozone will soon merge into the background atmosphere, according to one of the world's leading ozone experts, Professor John Pyle, professor of chemistry at Cambridge University and co-director of the National Centre for Atmospheric Science.
Greenland’s dark snow may start global warming ‘feedback loop’
Climate change march: Investors pledge to take their money out of firms blamed for climate change
Global climate change expert 'optimistic' that world can curb global warming
Badger found shot in the abdomen is 'proof' that cull is inhumane, activists say
Rockefellers go green: Rockefeller foundation divests funds in fossil fuel industries
- 1 Cyclist in Russia narrowly misses being hit by car and lorry
- 2 'F*ck it, I quit': KTVA reporter Charlo Greene quits live on air in spectacular fashion
- 3 What are your fingerprint words?
- 4 Gary Lineker involved in Twitter row after presenter rubbishes claims he will be warned by BBC over foul-mouthed tweets
- 5 Pink Floyd new album: Band unveil cover art for first record in 20 years
Scotland could still declare independence – even without referendum, says Alex Salmond
Scottish referendum results: Cross-party consensus collapses amid Tory-Labour spat on the 'English question'
Hilary Mantel 'should be investigated by police' over Margaret Thatcher assassination story, says Lord Bell
Plebgate MP Andrew Mitchell called officer a 'little s**t', claim court documents 'exposing ex-Chief Whip's 'record of abusing police'
Archbishop of Canterbury admits doubts about existence of God
Labour Party conference: Ed Balls to set out plan to freeze child benefit to balance books
£16500 - £20000 Per Annum: Clearwater People Solutions Ltd: We are currently r...
£100 - £125 per day: Randstad Education Crawley: KS2 PPA Teacher currently nee...
£40000 - £45000 per annum + pension, healthcare,25 days: Ashdown Group: An est...
£28000 per annum: Ashdown Group: IT Software Application Support Analyst - Imm...