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Andrew Xnn

This is a good paper on Ice Drift acceleration paper:

IPCC climate models do not capture Arctic sea ice drift acceleration: Consequences in terms of projected sea ice thinning and decline

http://web.mit.edu/~rampal/rampal_homepage/Publications_files/Rampal_etal2011.pdf

IPCC climate models underestimate the decrease of the Arctic sea ice extent. The recent Arctic sea ice decline is also characterized by a rapid thinning and by an increase of sea ice kinematics (velocities and deformation rates), with both processes being coupled through positive feedbacks. In this study we show that IPCC climate models underestimate the observed thinning trend by a factor of almost 4 on average and fail to capture the associated accelerated motion. The coupling between the ice state (thickness and concentration) and ice velocity is unexpectedly weak in most models. In particular, sea ice drifts faster during the months when it is thick and packed than when it is thin, contrary to what is observed; also models with larger long-term thinning trends do not show higher drift acceleration. This weak coupling behavior (i) suggests that the positive feedbacks mentioned above are underestimated, and (ii) can partly explain for the models underestimation of the recent sea ice area, thickness and velocity trends. Due partly to this weak coupling, ice export does not play an important role in the simulated negative balance of Arctic sea ice mass between 1950 and 2050. If we assume a positive trend on ice speeds at straits equivalent to the one observed since 1979 within the Arctic basin, first-order estimations give shrinking and thinning trends that become significantly closer to the observations.

Neven

Thanks, Andrew. I will summarize this paper this week.

Diablobanquisa.wordpress.com

Belchansky et al., 2008: Fluctuating Arctic Sea Ice Thickness Changes Estimated by an In Situ Learned and Empirically Forced Neural Network Model

pdf: http://journals.ametsoc.org/doi/pdf/10.1175/2007JCLI1787.1

Pete Williamson

I don't know what you call this. It's not really presenting new data, it isn't a comprehensive review, I think it's something like an opinion piece.

From BAMS Feb 2012 by Polyakov,Walsh and Kwok
http://flare.creighton.edu/zehnder/ATS%20533/misc/bams.pdf

It's looking at the evidence for dynamic and thermodynamic processes having a role to play in recent declines in arctic sea ice thickness. Accessible to an amateur like me.

Neven

Thanks a lot, Diablo and Pete.

Diablobanquisa.wordpress.com

Hi Pete.

I don´t agree Belchansky 2008 is "an opinion piece".
In my opinion, Belchansky et al. 2008 is interesting because it uses an alternative approach to estimate SIT during the period previous to the "new arctic state". And it offers a complete review of an elusive parameter as thickness, and its relations with AO and other factors. It shows where we come from.

Of course, Polyakov´s paper you quote is also very interesting and more updated (it was reported by Neven here: http://neven1.typepad.com/blog/2011/09/new-paper-by-polyakov-kwok-and-walsh.html )

Diablobanquisa.wordpress.com

Kwok 2011, The thinning of arctic sea ice: http://www.atmos.albany.edu/daes/atmclasses/atm305/Kwok-and-Untersteiner-2011.pdf

Neven

Ramapl et al. is up. Very interesting paper.

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