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Author Topic: Is the polar ice cap already at a miniumum? Is it a problem? Flowing?  (Read 2365 times)

Offline CliffordK

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I started looking at some of the Arctic Ice.

There is a cycle of ice melting, and reforming from about 4 million km2 to 15 million km2, with little change over the last decade in the total ice extent, although the minimum ice extent may be lower than in previous decades.
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

What is happening, or perhaps already has happened is that the old ice has disappeared from the North Pole, and all that is left is "young ice".



Look at some of the animations.

The Fowler Animations are probably the clearest to visualize the actual movement and flows of the ice.

Fowler Animation, GIF Format, 1982 to 2007
http://nsidc.org/news/press/2007_seaiceminimum/images/20070822_oldice.gif

Fowler Animation You-Tube, 1982 to 2010

ASMR-E Satellite View of Ice movement
http://noconsensus.files.wordpress.com/2009/05/arctic_amsr-e_flow_animation-40.gif  (2007, 2008)
(same as above, also 2007, 2008).

What is obvious from the videos.
ASMR-E satellite view shows the ice more as a viscous fluid rather than a solid or a sheet.  There are strong ocean currents including a circular pattern north of Alaska, and a current that pushes the ice down through about a 300 mile gap between Greenland and Svalbard.

It appears to me that much of the melting of the multi-year ice isn't from melting in place, but rather this ice flow into the North Atlantic.

My first question was whether Ice Breakers were contributing to this fluidity of the ice.  The official statement is that they are not contributing to it, although I still have to wonder if they allow more southern movement of the ice by opening up tracks in it, and breaking it up more than would otherwise happen with "natural forces".

However, I would have to imagine that tides, expansion contraction, ocean currents, and winds have a bigger influence on the overall ice movement.

Northern Commerce, of course, benefits by the reductions in the amount of ice.

Since the ice isn't melting from the edges towards the middle, but rather is pushed along the northern coast of North America and Greenland, one wouldn't anticipate large numbers of wildlife to become stranded on a shrinking iceburg, but rather they would naturally migrate onto land.

If we should choose to try to thicken and maintain the summer North Polar Ice.  I would suggest stringing a series of cables, drag chains, and deep water Buoys across the 300 mile stretch between Greenland and Svalbard.  The goal wouldn't be to prevent the natural southern migration of the ice, but rather to just slow it down a little.

While it might hinder a shipping channel, one probably should restrict shipping around the North East coast of Greenland, and North-West coast of Svalbard to avoid increasing the natural ice flow.

The biggest possible consequence I could foresee is that it could cause a temporary reduction of ice flow in to the North Atlantic, and perhaps a resulting increase in ocean temperatures.  It is likely that such buoys would periodically break away and would need to be picked up and returned every fall.

With any luck, perhaps in a 5-10 years period one could return the ice back to pre 1980's age & thickness.


 

Offline yor_on

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It's the end of the Arctic as we know it I think. The ice is no longer all year around but so called summer ice. It will open new routes for shipping, the death of polar bears and other arctic wildlife, like the plankton that is the primary step in most marine life food chains. It may in due course, or already have started, to change the streams. Without those a lot of USA and northern Europe will get a colder climate. The increase of 'phreak storms' seems a good sign that the Earth is experiencing a turbulent period with oscillations, going from one extreme to another, not that is that extreme yet. Give it another ten years and see.
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And of course a resource race/war exploiting the Arctic for its resources, and possibly Greenland too. China has already started to position itself for getting in the game, as well as USA Canada, Russia, and the Nordic countries too I would guess
« Last Edit: 04/02/2011 14:30:41 by yor_on »
 

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