A hole in Earth ’s protective ozone stratum above the Antarctic has become an one-year event for the last 25 years , greatly increasing the South Pole ’s exposure to ultraviolet ray . Now , the same thing is happening above the Arctic Circle .
The ozone layer is see roughly between 20 and 25 miles above our major planet ’s surface . Primarily compose of the oxygen compound ozone , this layer serves to absorb about 97 - 99 % of all ultraviolet brightness that get hold of Earth from the Sun , shield us from its more dangerous effects . But due to the heavy use of various man - manufacture compounds — in particular chlorofluorocarbons , or CFCs , which have since been mostly blackball — the ozone layer has become depleted , opening up holes over as much as 5 % of the Earth ’s surface ever since the mid-1980s .
Until now , the immense majority of those fix were found high above Antarctica , but now it appears this severe ozone depletion has migrated to the other perch . An outside team of researchers discovered that a mixing of ozone - consume pollutant and unusually cold temperature above the North Pole motor the creation of a new Arctic ozone hole unlike any we ’ve regard before .
The glacial regions lean to draw these holes because of a phenomenon known as the diametric vortex , a circulation pattern in the atmosphere make by cold temperature and the rotation of the Earth that greatly increases the amount of regular chemical substance being converted into ozone - depleting ones . This past year see specially cold temperature and , as a result , an unusually long and severe polar vortex . The result was the creation of means more ozone - eat up chemicals than normal , making the shaping of a full - blown ozone hole in the Arctic all but inevitable .
University of Toronto researcher Kaley Walker explains :
“ In the 2010 - 11 Arctic winter , we did not have temperatures that were low than in the previous cold Arctic winter . What was unlike about this yr was that the temperatures were low enough to generate ozone - exhaust forms of chlorine for a much long menstruum of fourth dimension . Arctic ozone departure events such as those take note this class could become more frequent if winter Arctic stratospheric temperature decrease in future as Earth ’s climate change . ”
If you ’re try on to look on the bright side , the good news is that the Arctic arctic vortex is much smaller than its Antarctic similitude , which means the Northern ozone hole also covers far less flat coat than the southerly one . But that ’s about it for good news — the Arctic ozone mess is much more nomadic , and it ’s capable of reaching human population centers in the Arctic Circle that do n’t survive down in Antarctica . That means the threat posed by the Arctic ozone hole is potentially heavy , in the short term , than its southerly counterpart .
The researchers also point out that without the 1989 Montreal Protocol , which ban many of the most spartan ozone - depleting pollutants , we would probably have long since reach out the point where an Arctic ozone hole forms ever year . As it stands , it ’s not exculpated whether this is go to be a regular thing , or represents a comparatively strange occurrence . Either way , it unfortunately is n’t likely the last clock time we ’ll see such a cakehole — the effects of CFCs and other chemicals is long - lived and will likely hover on for decades more .
ViaNature . simulacrum by the U.S. Geological Survey onFlickr .
AntarcticaAtmosphereScience
Daily Newsletter
Get the best tech , science , and acculturation intelligence in your inbox daily .
news show from the future , delivered to your nowadays .
You May Also Like
