Hello mga Ka-Espiya...
Thanks for the shared info .
http://ph.news.yahoo.com/scientists-worried-arctic-record-ozone-loss-192032806.htmlThe trigger was the polar vortex, a large-scale cyclone that forms every winter in the Arctic stratosphere but which last winter was born in extremely cold conditions, Gloria Manney, of the Jet Propulsion Laboratory in California, told AFP in email.
"The ozone destruction began in January, then accelerated in late February and March, so that ozone values in the polar vortex region were much lower than usual from early March through late April, after which the polar vortex dissipated.
It was mentioned here that the trigger was the
polar vortex in the arctic region..
What is a polar vortex?A polar vortex is a persistent, large-scale cyclone located near one or both of a planet's geographical poles. On Earth, the polar vortices are located in the middle and upper troposphere and the stratosphere. They surround the polar highs and are part of the polar front.
Arctic and Antarctic variationThe vortex is most powerful in the hemisphere's winter, when the temperature gradient is steepest, and diminishes or can disappear in the summer. The Antarctic polar vortex is more pronounced and persistent than the Arctic one; this is because the distribution of land masses at high latitudes in the northern hemisphere gives rise to Rossby waves which contribute to the breakdown of the vortex, whereas in the southern hemisphere the vortex remains less disturbed. The breakdown of the polar vortex is an extreme event known as a Sudden stratospheric warming, here the vortex completely breaks down and an associated warming of 30-50 degrees Celsius over a few days can occur. The Arctic vortex is elongated in shape, with two centres, one roughly over Baffin Island in Canada and the other over northeast Siberia. In rare events, the vortex can push further south as a result of axis interruption, see January 1985 Arctic outbreak.
Ozone depletionThe chemistry of the Antarctic polar vortex has created severe ozone depletion. The nitric acid in polar stratospheric clouds reacts with CFCs to form chlorine, which catalyzes the photochemical destruction of ozone. Chlorine concentrations build up during the winter polar night, and the consequent ozone destruction is greatest when the sunlight returns in spring (September/October). These clouds can only form at temperatures below about -80°C. Since these temperatures are rarely reached in the Arctic, ozone depletion at the north pole is much less severe than at the south. Accordingly, the seasonal reduction of ozone levels over the Arctic is usually characterized as an "ozone dent," whereas the more severe ozone depletion over the Antarctic is considered an "ozone hole." This said, chemical ozone destruction in the 2011 Arctic polar vortex attained, for the first time, a level clearly identifiable as an Arctic "ozone hole".
The nitric acid in polar stratospheric clouds reacts with CFCs to form chlorine, which catalyzes the photochemical destruction of ozone.
Now aside from CFCs coming from human activities to continue their high standard of living.. we should also try to check as well what are the OTHER sources of CFCs that adds up to this mess.
I would just like to add another point of view here.
We know from our High School days that there is another source of naturally occurring source of CFCs..
and this are from........ The
Volcanoes...
Last year of 2010 has been a year of too much volcanic activity.. too disrupting that it cancels and postponed the the air flights in northern Europe for weeks because of too much volcanic ash that were released in the atmosphere and in into the Jet stream as well.
Has anyone still remember the famous
icelandic volcano which it's name is so difficult to pronounce that even CNN reporters had a hard time calling its name?
The eruption in
Eyjafjallajökull (glacier of Eyjafjöll) in 2010 was notable because the volcanic ash plume disrupted air travel in northern Europe for several weeks; however, Eyjafjallajökull is a minor volcano in Icelandic terms. In the past, eruptions of Eyjafjallajökull have been followed by eruption of the larger volcano Katla, but following the 2010 eruption no signs of an
imminent eruption of Katla were seen.[2]
The eruption, in May 2011, at GrÃmsvötn under the Vatnajökull glacier sent thousands of tonnes of ash into the sky in a few days, raising concerns of a repeat of the travel chaos seen across northern Europe.
Top volcanic eruptions of 2010:1. Eyjafjallajökul, Iceland
2. Mount Merapi, Indonesia
3. Tungurahua, Ecuador
4. Pacaya, Guatemala
5.
Kliuchevskoi, Kamchatka, Russia6.
Sheveluch, Kamchatka, Russia7. Santiaguito, Guatemala
8. Mount Sinabung, Indonesia
9.
Kizimen, Kamchatka, Russia10.
Cleveland, Alaska
Reported Volcanic Eruptions for 2011GrÃmsvötn Iceland
Katla Iceland Puyehue-Cordón Caulle Chile
Planchón-Peteroa Chile
Turrialba Costa Rica
Telica Nicaragua
Cleveland United States
Kliuchevskoi Russia
Bezymianny Russia
Aso Japan
Kirishima Japan
Karangetang [Api Siau] Indonesia
Lokon-Empung Indonesia
Soputan Indonesia
Merapi Indonesia
Aoba Vanuatu
Rabaul Papua New Guinea
Tofua Tonga
Nabro Eritrea
DurationThe Antarctic Polar Vortex forms during the polar winter. The ozone hole lasts from August to November.
Outside earthOther astronomical bodies are also known to have polar vortices, including Venus (double vortex - that is, two polar vortices at a pole [1]), Mars, Jupiter, Saturn and Saturn's moon Titan.
Just an additional info to all of us.
Thanks.
Peace ....
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sources:
http://en.wikipedia.org/wiki/Polar_vortexhttp://topics.nytimes.com/top/news/international/countriesandterritories/iceland/eyjafjallajokull/index.htmlhttp://news.discovery.com/earth/top-volcanic-eruptions-of-2010.html
