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Author Topic: Do icebreakers have a lasting impact on sea ice?  (Read 10110 times)

Gallagher, Edward R.

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Do icebreakers have a lasting impact on sea ice?
« on: 07/02/2011 06:30:02 »
Gallagher, Edward R.  asked the Naked Scientists:
   
My question is has anyone thought about the consequences on the many ice breakers that are breaking up the sea ice.

I would think that it must have an impact on the ice shelf. The continuous breaking of the sea ice and the multiple sea courses that the ships are taking are allowing the ice to break up quicker every year.

I think that there should be a moratorium placed on sea travel into the arctic or at least limit the shipping lane.

I know for a fact that lake ice will break up far faster if a boat breaks a path through it.

This probably allows the light and the sun to facilitate breakup and then allows the wind to break it up days faster than a lake that is left an disturbed.
 
Ed Gallagher


What do you think?
« Last Edit: 07/02/2011 06:30:02 by _system »


 

Offline CliffordK

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Do icebreakers have a lasting impact on sea ice?
« Reply #1 on: 07/02/2011 22:04:40 »
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.

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.
I asked the same question a couple of weeks ago.  See link above for more notes.

The official statement is that the icebreakers are not greatly impacting the breakup of the sea ice.  But, I also have been wondering.  If you take a chunk of ice a few feet thick, and crack it...  then what?

The arctic is millions of square kilometers, so a few paths from ice breakers shouldn't be that big of a contribution, but even a little contribution might make a big difference.  I am having troubles finding data on the actual paths they are taking though.

It would be reasonable to restrict ice breakers from some of the core places that ice is exiting from the Arctic, the East coast of Greenland, and even to a lesser extent northwest coast of Greenland.

Also limit scientists and tourists from bashing through to the North Pole.

Keep in mind though..
The Arctic Ice has always flowed, and was never a flat sheet....  I remember seeing old photos 50+ years old showing the lumpy, bumpy texture of the Arctic. 

Most of the flowing seems to be due to strong currents up through the Bering Strait, although perhaps some Atlantic flow too.

There might be methods one could implement to keep the ice in the Arctic, but one should keep in mind there could be unintended consequences from one's actions.
 

Offline yor_on

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Do icebreakers have a lasting impact on sea ice?
« Reply #2 on: 10/07/2011 06:35:52 »
It freeze behind them, although you won't have it frozen all the way down. New ice keeping it together becomes very quick. "Canals freeze over so quickly that 10 minutes after the icebreaker had passed, the residents of Dudinka can go on the ice to fish; four hours later the ice is strong enough to hold a truck." And I've actually seen it myself.  The Northeast Passage: roads in the ice 

But there are other trouble brewing now, as the icebreakers no longer are as necessary. 'An increasing amount of seaborne traffic is moving along a new Siberian coastal route, cutting journey time and boosting trade prospects. "short-lived forcing of about 4.5 gigatons of black carbon from Arctic shipping may increase the global warming potential due to ships' carbon dioxide emissions by some 17 to 78%." according to a Finish study last year. new shipping routes on the 'roof of the world'.
 

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Do icebreakers have a lasting impact on sea ice?
« Reply #2 on: 10/07/2011 06:35:52 »

 

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