The media is getting excited again over our rapidly disappearing seaice which blew past the 2007 record and bettered it by 500,000 squarekilometes to hit a total of 3,400,000 sq kilometers.
In fact my prediction of 2007, before the record was particularlyapparent then has been powerfully confirmed as the Arctic sea ice hasnow clearly entered its terminal stage of breakup and collapse. Itis quite reasonable to expect almost all winter ice to melt out eachsummer well before the end of the decade.
We also have hard confirmation that this has been brought about by awarm water distribution shift into the North Atlantic from theSouthern Hemisphere. Understand that this has nothing to do fromimagined global warming or CO2 production.
The media of course will continue to babble about the end of theworld as we know it.
It is quite plausible though that we may return to Bronze Ageconditions. We have certainly seen a recovery of Medieval Warm Spellconditions. This all fits well with a thousand year cycle broughtabout possibly by a strong variation in the flux of cold waters intothe Deep in the Antarctic. That is the one thing that I can identifyas having the real power to do all this. Major aspects of thesewaters are in fact changing. Whatever is happening, the circumpolarcurrent is drawing a lot less heat and the ice is expanding there.
The result has been to dump surplus heat into the north Atlantic forthe past forty years or so. This has now destroyed or weakened allthe multiyear ice in the Arctic setting up the present collapse.
Arctic Ice “Rotten”to the North Pole, scientist says
By MargaretMunro September 21, 2012
NASA handout imageshows how satellite data reveals how the new record low Arctic seaice extent, from September 16, 2012, compares to the average minimumextent over the past 30 years (in yellow). Sea ice extent maps arederived from data captured by the Scanning Multichannel MicrowaveRadiometer aboard NASA's Nimbus-7 satellite and the Special SensorMicrowave Imager on multiple satellites from the DefenseMeteorological Satellite Program. (REUTERS/NASA/Goddard ScientificVisualization Studio/Handout)
http://www.vancouversun.com/news/national/Arctic+Rotten+North+Pole+scientist+says/7279002/story.html
When David Barberfirst headed to the Arctic in the 1980s, the ice would typicallyretreat just a few a kilometres offshore by summer’s end.
Now he and hiscolleagues have to travel more than 1,000 kilometres north into theBeaufort Sea to even find the ice.
And it’s nothinglike the thick, impenetrable ice of Arctic lore.
This year the ice is“rotten” practically all the way to the North Pole, says Barber,a veteran Arctic researcher and director of the Centre for EarthObservation Science at the University of Manitoba.
“The multi-year ice,what’s left of it, is so heavily decayed that it’s really nolonger a barrier to transportation,” he says, explaining how meltponds have left much of the ice looking like Swiss cheese.
“You could havetaken a ship right across the North Pole this year,” says Barber,whose research team was involved in a 36-day research cruise in theBeaufort on a Canadian Coast Guard ship.
The Arctic ice lossthis summer shattered the record set in 2007. It hit the low pointlast weekend, covering 3.41 million square kilometers, or 24 percent, of the Arctic Ocean, according to the U.S. National Snowand Ice Data Center, which has been tracking the ice with satellitessince the late 1970s.
This year’s minimumis nearly 50-per -cent lower than the 1979 to 2000 average.
While the ice lossdocumented by the NSIDC is record-setting, Barber says the reality inthe Arctic is ever worse.
The U.S. numbers areabout “a 15-per-cent over-estimation of how much ice is actuallythere,” says Barber. That’s because satellites have troublediscerning ice conditions, he says, and will count heavily decayedice as solid.
Regardless of who isdoing the counting, he and other scientists consider the ice lossremarkable. And they say the impact will be felt far beyond theArctic.
“It’s a globallysignificant change on our planet,” Barber said in an interview.
Many expect the Arcticcould be “seasonally ice free” in the summer within a decade.
“I’d say 2020,plus or minus five years,” says Barber.
At that point theplanet will be without its icy dome for the first time in eons.
A recent study thatlooked back 1,450 years indicates the current Arctic ice melt hasalready eclipsed the medieval warm period of about 1,000 years ago.
“The level that weare at now is unprecedented over the last 1,450 years,” saysBarber. “And as far as we know we have to go back over a millionyears to find a period when the Arctic was seasonally ice-free in thesummer.”
The Arctic melt isalso happening faster than at any time in the planet’s past, saysBarber, noting that the geological and historical records indicate ittook tens of thousands of years to move to a seasonally-ice-freeArctic in the past.
“Now we are gettingthere in tens of years, not tens of thousands of years,” he says.“And we don’t know how the Earth is going to respond because wehave never seen such a rapid change before.”
Environmentalists andscientists were quick this week to call for cuts in greenhouse gasemissions to slow the global warming that is melting the ice.
James Hansen, aprominent and outspoken NASA climate scientist, said the Arcticmelting shows the risks society is running by failing to limitemissions produced by burning oil, coal and gas.
“The scientificcommunity realizes that we have a planetary emergency,” saidHansen. “It’s hard for the public to recognize this because theystick their head out the window and don’t see that much going on.”
“We can see veryviscerally in the ice how warming temperatures are changing theEarth’s environment,” Walt Meier, of U.S. NSIDC told a mediabriefing this week.
He and otherresearchers say the Arctic melt is just the tip of the iceberg.
Rising globaltemperaturess are also transforming northern ecosystems,melting permafrost and shattering ancient ice shelves. Giant icebergsfrom the disintegrating shelves are now sailing through Canada’sBeaufort Sea, creating a new hazard for oil rigs, says Barber, whoseteam is involved in national and international efforts to get a readon the new Arctic reality and it implications.
Global warming is alsoaltering the oceans. More warm, salty water from the North Atlanticis flowing in the Arctic, and may be helping speed up ice melt.
Another concern isrising sea level. Arctic ice is already in the ocean so does notraise sea level when it melts. But the extra heat being absorbed bythe Arctic Ocean due to the ice loss appears to be acceleratingmelting of the Greenland ice sheet, which does raise sea levels.
The growing expanse ofopen Arctic water, which traps a lot more of the sun’s heatthan reflective ice, is also altering polar storms and winds,says Barber. And this in turn may be linked to the increasinglystrange and extreme weather seen from New Orleans to Newfoundland.
Statistical evidencesuggests the changes in the Arctic are slowing the jet stream andpushing it further south, leading to more “persistent” climatepatterns – be it rain, drought or sunshine, he says. Thechallenge now is to understand the physical mechanism.
”Our society, ourcivilization and how we live our lives – it’s all predicated on astable climate system,” says Barber, who notes that the planet hasundergone abrupt climate change in the past and could do so again.
“The take-homemessage for people is we are running an experiment with Earth’sclimate system,” says Barber, and greenhouse gases are contributingto enormous change – like melting Arctic ice – thatis happening much faster than anticipated.
Arctic expertpredicts final collapse of sea ice within four years
As sea ice shrinks to record lows, Prof Peter Wadhams warns a'global disaster' is now unfolding in northern latitudes
http://www.guardian.co.uk/environment/2012/sep/17/arctic-collapse-sea-ice?newsfeed=true
one of the world'sleading ice experts has predicted the final collapse ofArctic seaice in summer months within four years.
In what he calls a"global disaster" now unfolding in northern latitudes asthe sea area that freezes and melts each year shrinks to itslowest extentever recorded, Prof Peter Wadhams of CambridgeUniversity calls for "urgent" consideration of newideas to reduce global temperatures.
In an email to theGuardian he says: "Climate change is no longer something wecan aim to do something about in a few decades' time, and that wemust not only urgently reduce CO2 emissions but must urgentlyexamine other ways of slowing global warming, such as thevariousgeoengineering ideas that have been put forward."
These includereflecting the sun's rays back into space, making clouds whiter andseeding the ocean with minerals to absorb more CO2.
Wadhams has spent manyyears collecting ice thickness data from submarines passing below thearctic ocean. He predicted the imminent break-up of sea ice in summermonths in 2007, when the previous lowest extent of 4.17 millionsquare kilometres was set. This year, it has unexpectedly plunged afurther 500,000 sq km to less than 3.5m sq km. "I have beenpredicting [the collapse of sea ice in summer months] for many years.The main cause is simply global warming: as the climate has warmedthere has been less ice growth during the winter and more ice meltduring the summer.
"At first thisdidn't [get] noticed; the summer ice limits slowly shrank back, at arate which suggested that the ice would last another 50 years or so.But in the end the summer melt overtook the winter growth such thatthe entire ice sheet melts or breaks up during the summer months.
"This collapse, Ipredicted would occur in 2015-16 at which time the summer Arctic(August to September) would become ice-free. The final collapsetowards that state is now happening and will probably be complete bythose dates".
Wadhams says theimplications are "terrible". "The positives areincreased possibility of Arctic transport, increased access to Arcticoffshore oil and gas resources. The main negative is an accelerationof global warming."
"As the sea iceretreats in summer the ocean warms up (to 7C in 2011) and this warmsthe seabed too. The continental shelves of the Arctic are composed ofoffshore permafrost, frozen sediment left over from the last ice age.As the water warms the permafrost melts and releases huge quantitiesof trapped methane, a very powerful greenhouse gas so this will givea big boost to global warming."
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