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View Full Version : Discussion: Future Ice Free Summers in the Arctic



Fraser
2005-Aug-24, 05:44 PM
SUMMARY: Climate scientists are predicting that the Arctic Ocean could be completely free of ice during the summer within 100 years thanks to rising ocean temperatures. Several feedback mechanisms will also accelerate these changes. For example, the white ice reflects radiation from the Sun, and contributes to lower temperatures. As the ice melts, the region becomes darker and the melting should speed up.

View full article (http://www.universetoday.com/am/publish/ice-free_arctic_after_100_years.html)

What do you think about this story? Post your comments below.

om@umr.edu
2005-Aug-24, 05:48 PM
Hi, Fraser.

I certainly hope this dire prediction is wrong.

Good scientific investigations of the things that cause climate change, from variations in the Sun to greenhouse gases produced by combustion of fuels here on Earth, are needed in order to sort out cause and effect as quickly as possible.

Again, thanks for this interesting report.

With kind regards,

Oliver
http://www.umr.edu/~om

ChrisColes
2005-Aug-24, 10:48 PM
Not so very long ago we had a news item on BBC Radio 4 announcing that scientists had discovered a crack down the centre of europes largest ice sheet, (which I took as being Greenland). So? The news item dissappeared without a trace. Soon afterwards, we started getting news items about the theory that all the ice on Greenland would dissappear in the next 100 years or so. No one seems to be taking on board the implications for that ice melt, particularly the loss of most of the ocean side cities.

But my thinking has been further down the line for some years, ever since I read in Scientific American about the great waterfall of water that flows between the Newfoundland coast and Greenland. One illustration showed a cross section of the sea bed on that line, between the two coasts; it showed a lip, a raised section just before the drop into the abiss.

What do we do if the greenland ice sheet suddenly melts, calves great icebergs that block that waterfall of water?

I have been intrigued for a long time about the fact, yes, fact; that as temperatures have risen in the past, they suddenly drop back again into an ice age. Again and again, we see, from ice cores, a graph showing the temperature suddenly dropping away.

What if the sudden melting of the greenland ice sheet blocks the great conveyor? That would be just like suddenly plugging the sink, the flows stops instantly.

I believe that is the mechanism, the means if you will, that precipitates that sudden drop in temperature. Ergo, we get the start of the next ice age.

And will someone tell me how, if I am right and that suddenly happens; how do we melt that blocking ice? All thousands of cubic Kilometres of it......

And if you look at the speed that we have lost some of the major ice sheets in Antartica, in weeks, we could be there tomorrow.......

Food for thought.

Greg
2005-Aug-25, 07:28 AM
I am familiar with such speculation. As it turns out the warm ocean current conveyor belt is one of multiple components that effects arctic ice. Everything else being equal, such a shutdown would trigger an ice age, but all things are not equal. The latest article I read about the effects of glacial melt shutting down the conveyor belt (and there is good evidence that this is occurring already) concluded that the cooling effect of this event would be regional and not global. They suggested that the effects of global warming would be nullified in the region that this was happening in for about 50 years, or until the glacial melt was over with. So the northeast U.S., the Canadian maratimes, England and perhaps Quebec would see no net global warming in the next 50 years, which would make the region relatively cool compared to other areas around the globe. Europe would warm up as well as the SE U.S. and the tropical waters would be warmer, making for more and more ferocious cyclonic activity since the heat release valve going north would be shut off.

mark mclellan
2005-Aug-25, 11:49 AM
what percantage of habitable land would be lost to the rising tides and frozen tundras ? how many millions of people will be displaced? will there be enough agricultural land left to support this condenced population?will we slip back into a version of the dark ages?....................or will we actualy cope a lot better than some of the doomsdayers believe? ;)

Eric Vaxxine
2005-Aug-25, 12:52 PM
An ice age will not change our level of technology. We will fly food in. It will just be very costly and the more resilient of us will survive.

The general public will deal with a new ice age when it reaches their front door. :unsure:

When Europe drops 10c permanently....the population will probably just start skiing to work.
I feel it is almost impossible to maintain this calm period we are in. There is going to be change in the next 10 or 100 years.
When the running water stops and electricity fails ... THEN we'll see reaction !

Heaven forbid something strikes us from above.!

cran
2005-Aug-25, 04:49 PM
Feedback cycles, responses and rebounds all operate on different time scales... leading to uncertainties in predicting what will happen and where... add to that an unknown number of climatic oscillations ... from daily, to seasonal, annual, decadal, up to cycles ranging over hundreds of millions of years...
At this stage, we can only monitor and make 'running estimates'... and which ever way the regional and global climates move, it will be uncomfortable (perhaps locally or regionally catastrophic) and adjustments will need to be made ...
If sea levels continue to rise, then there will be mass movement of populations to higher, and generally less productive ground, and new more intensive forms of agriculture will need to be implemented if we are not to face (even more) widespread famines... it will not happen overnight...
If a new glacial period emerges, and sea levels fall, then water tables will also fall, and sea ports will become river ports; new coastal lands will open up but require time and/or resources to become agriculturally productive, and offshore islands may well become onshore bluffs... it will not happen overnight...
Whatever happens, there will be 'trade-offs' (gains and losses) ... it has always been this way... it is only of greater effect now because we have become more 'locked' to our locations ... and because we are running out of places to 'spread' into.

lswinford
2005-Aug-25, 05:17 PM
Back in the 1960's there were popular articles on musings of building a dam across the Baring Straits between Siberia and Alaska. The idea was to pump arctic water out, bringing the gulf stream up, and melting the arctic ice. Why? It would turn the massive and comparatively flat tundra into vast farming lands. Obviously finances, politics, and practicality prevailed.

There also were plans to build special tankers and fleets of ice breakers, of which the Soviet Union embarked upon to some degree for a while, to keep open sea lanes for oil and mineral transport.

There is a problem, however, and it seems to be hiding in Siberia. While the polar caps may be melting, and Alaskan permafrost growing less permanent, Siberia has been keeping very, very frigid winters recently. US News, January 26, 1987, "...Record Cold Wave"; UPI report, January 10, 2001, "Record Cold Grips Siberia"; and check out where NOAA said the cold spell we North Americans had in January, 2003 came from: http://www.noaanews.noaa.gov/stories/s1084.htm. Just as the magnetic north pole is not anywhere close to the geographic north pole, the center of Northern Hemisphere winters may be shifted too, though in a different direction.

Ah, but the 'good old days' : http://www.islandnet.com/~see/weather/alma...02/alm02feb.htm (http://www.islandnet.com/~see/weather/almanac/arc2002/alm02feb.htm)

cran
2005-Aug-25, 05:40 PM
The idea was to pump arctic water out, bringing the gulf stream up, and melting the arctic ice. Why? It would turn the massive and comparatively flat tundra into vast farming lands. Obviously finances, politics, and practicality prevailed. That... and the realisation of the damage that would be caused to the cities and infrastructure in Alaska (and elsewhere) that had set foundations in the permafrost... :P
Later, it was shown that thawing out the tundra would also disrupt ecosystems, and release a lot more CO2 into the Arctic atmosphere, and cause even more ruptures to the trouble-plagued northern Siberian and Russian oil pipelines... :ph34r:

Guest
2005-Aug-27, 06:02 AM
Sounds like a great idea until you realize that people actually live in these places and need things to remain the same to maintain their culture and livlihoods.
There was a recent article on this forum (I believe) that was published in Russia that indicates that West Siberian permafrost is now in the latter stages of melting and the Eastern permafrost is now in the early stages of melting. I am not sure, but I think this happened within the last 10 years.