Cold temperatures’ created the hole,
which is about three times the size of Greenland.
A
massive ozone hole – in all probability the biggest on records in the north –
has released in the skies above the arctic.it rivals the better –known
Antarctic ozone hole that forms in the Southern Hemisphere each year.
Recorded
–low ozone levels currently bounce across much of the central Arctic, covering
an area about three times the size of Green-land .The hole doesn’t creep up
peoples health, and will in all probability disappear in the atmospheric phenomenon
that will go down in the record books. From my point of view, this is the first
time you can see about a real ozone hole in the Arctic, says Martin Dameris, an
atmospheric scientists at the German Aerospace center in oberpfaffenhofen. Ozone
normally forms a protective blanket in the stratosphere, bout 10 to 50 kilometers above
the ground, where it protections life from solar ultraviolet radiations. But
each year in the Antarctic winter, glacial temperatures’ allow high –altitude
clouds to coalesce above the South Pole. chemicals, including chlorine and
bromine, which come from refrigerants and other industrial sources, tigger
reactions on the surfaces of the those cloud that chew away at the ozone layer .these
cold conditions are much rarer in the Arctic, which has more –variable temperature’s
and isn’t usually primed for ozone depletions, says jens -Uwe Groom, an
atmospheric scientists at the julich Research center in Germany,
But
this year, powerful westerly winds flowed around the North pole and trapped
cold air in a polar vortex .there was more cold air above the arctic than in
any winter recorded since 1979,says Markus Rex ,an atmospheric scintist at the
Alfred Wegener insitiute in Potsdam,German .in the chilly tepratures ,the high
–altitude clouds formed and the ozone –destroying reactions began.
Balloon measurements
Researcher’s measure ozone levels by releasing
weather balloons from observing stations around the Arctic.by late march, these
balloons had measured a 90% drop in ozone at an act of 18 kilometers, which is
right in the heart of the ozone layer. Where the balloons would normally
measure around 3.5 parts per million of ozone, they recorded only around 0.3
parts per million, says Rex. that beats any ozone loss we have seen in the past
he notes the Arctic experienced ozone depletion in 1997 and in 201 ,but this
year loss looks on track to surpass those. We have at least as much loss as in
2011, and there are some indications that it might be more than 2011 says
Gloria Manney ,an atmospheric scientist at North west research Associates in Socorro,
New México. She works with a NASA satellite instrument that measures chlorine
in the atmosphere, and says there is still quite a bit of chlorine available to
deplete ozone in the coming days. The Arctic ozone hole is not a health threat
because the sun is only just starting to rise above the horizon in high latitudes,
says Rex. however, in the coming days ,there is a small possibility that the
hole will drift to lower latitudes over more populated areas-in which case
,people might need to apply sunscreen to avoid sunburn ,it wouldn’t be
difficult to deal with, Rex says.
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