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iceman

The animation is indeed quite striking.
Someone posted a statistic on ASIF a while back of the percentage that Fram export accounts for of total annual peak-to-trough volume change. I don't remember the number but it's fairly small (~10%?). However, it seems likely that Fram export can have a disproportionate effect on the melt season. A strong export in the spring, for example, would thin out ice in the central basin and make it more susceptible to insolation.

I Ballantinegray1

I'd been noting this 'odd' behaviour over on other sites that i use so am pleased to see Wipneus coming up with some excellent graphics to highlight this!! Through the winters of the 80's did we not see massive losses via Fram ( the first signs of thing to come?) and so why should we not expect to see similar again over coming years?

The animation of ice through the noughties also shows Fram taking the older ice throughout the year ( almost like the basin vomiting the contents of its stomach !).

I was very surprised to see 2014 repeating the retention of 2013, I'd have thought it far more likely for an average or warm year to follow on from the 'cool year' so this coming melt season must be even less likely to see another high retention year? Put it another way what would 08' have looked like in Sept if we had seen a repeat of 07' that year?

I'm sure that , over here, we all know what the prognosis for the ice is midst the trends for steadily increasing temps around the basin ( and that 'warming' heading south as the recent report from Finland shows). In other places the recent swathe of reports of the ice being 'more resilient' has lead to an upsurge in 'recovery clamor' and any reminders of just how fragile the basin is leaves one labelled as 'doomsayer' or 'catastrophist' and not as a realist!

wayne

Nice animation, but it may give the illusion of no flow in July-August when sea surface temperatures were near +5 C , so there was a great deal of melting. The number of frames may not be sufficient to suggest melting. I would work on sst overlay o confirm the lack of flow out.

Veli Kallio

The lateral viscosity of the thin Arctic sea ice cover has continued to lower from mid-November to 2 January 2015. (The lowering lateral viscosity of sea ice is combination of larger sea ice area of thin ice and being formed of this winter's ice.)

Six weeks ago (around mid-November 2014)just one quarter of the high Arctic Ocean basin (above 85° north) was covered by a thin this winter season's ice. This had now (by 2 January 2015) doubled, covering roughly two quarters above 85° north. The fresh ice is about one metre thick and it is also physically weaker than multiyear ice. So it breaks easily.

In addition, the continuing crushing and tumbling of large amounts of recently formed ice into pack ice (behind the North Pole) does not allow the saline brine within sea ice to drain out easily. This is because the brine is drained by gravity; if the block of ice turns upsided down the draining brine reverses to the opposite direction. As the ice is as restless as it is now, the direction of gravity field within ice blocks keeps changing. Thus ice remains more saline. This winters' "thick" pack ice behind North Pole will, therefore, melt very easily. (Ice rejects salt if it stays upright long enough, but this threshold has seen its own tipping point this winter.)

The US Navy's graph is best viewed at 400% screen setting: http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif

The ice is being pushed away from Russia towards Canada and the Fram Strait at a very high rates. This is increasingly suggesting that the remaining old ice stocks in front of the Fram Strait will soon be sucked out into the Atlantic Ocean. In the other worlds, the old ice runs out.

The dark blue ice legend in US Navy's graph is newly formed, but crushed ice behind the North Pole (pack ice) which I referred above. This thick recently formed ice in ice pack has relatively high salinity due to ice overturning constantly since its formation. We may well be in course to the first recorded ice-free season in the Arctic Ocean.

I am curious to see how the ice behaves after the last remainders of the second polar quarter old ice is lost to the Atlantic Ocean and the newly forming sea ice will face the full force of the Atlantic waves. That should mean extremely highly fractured sea ice across the Russian side by the return of spring 2015 sunlight.

I think we are witnessing a historic transition right now as the lowered lateral viscosity of sea ice is unable to withstand the shearing forces of waves, wind and sea currents that keeps the ice loose and on the perennial move.

Veli Kallio
Sea Research Society

I Ballantinegray1

Thanks for that Veli!, i had never considered the impact of ice tumbling before. I had mulled the impact of loss of snow cover that over wash of fragmented ice might drive but not an interruption to the loss of salt from FY ice due to rolling/tumbling of ice?

I recall a paper from 09' noting a change in sea ice at formation due to increased wave activity ( now forming 'pancake ice' like we see form on rivers?) so the new ice forming across the basin might actually be 'shaped'in a way promoting rolling as the ice thickens esp. when swells are present?

I'd also noted that the resumption in export had zoned in on the Atlantic sector multiyear ice ( from the past 2 years of retention?) and that we appear to be currently down to less than 50% of that present in Oct with transport still ongoing. The L.P.'s , south of Svalbard, are first dragging the ice toward Fram ( on the easterly element of the pressure system) and then driving it into Fram 9 when the northerly element takes hold). With some doozies now in the forecast these L.P. systems seem set to run for a while longer so just how much ice will be left over Fram come spring? Trading 2.5m+ ice for sub 1m ice does not appear a good trade in my book.

crandles

I can see that 'tumbling' as in turning 90 degrees at a time would impede brine rejection. However that requires very small pieces of roughly same width as depth. Isn't that unlikely and repeatedly turning upside down more likely?

If just repeatedly turning upside down, doesn't the brine have an easy path back down along the route it has carved when going in the opposite direction? Does that impede brine rejection all that much?

Chris Reynolds

Veli,

How do you measure lateral viscosity?

Crandles,

I agree, it seems to me that it is the very act of mechanical deformation that opens up fractures and facilitates brine drainage.

Jai Mitchell

Just wanted to share this FANTASTIC open letter from Michael Mann in the Bulletin of the Atomic Scientist

http://bos.sagepub.com/content/71/1/33.full.pdf+html

The Serengeti strategy:
How special interests try to
intimidate scientists, and
how best to fight back

Ostepop1000

[edit Neven: Sorry, no Serengeti strategy here. Take the hyena food elsewhere, please.]

Leslie Graham

Recently 78 climate researchers from 24 countries, together with many other colleagues, worked for seven years on a new climate reconstruction covering the same period as Mann.
Their new study was published in Nature Geoscience. It is based on 511 climate archives from around the world, from sediments, ice cores, tree rings, corals, stalagmites, pollen or historical documents and measurements etc
All data are freely available for you to check.
And guess what this 500 man-years or research shows?
Yep - it's a 'Hockey Stick'!
Almost identical to Mann's brilliant original.

There are also at least a dozen other 'Hockey Sticks' that also verify and corroborate Mann's original making it one of THE most robust theories in science history.

Don't you just hate that?

The rest of your mishmash Gish-gallop of the same old wearisome thousand-times-falsified junk and baseless slander isn't even worth parsing for the nth time.

Whatever you are being paid to write this nonsense it's too much.

Ostepop1000

[Edit Neven: Sorry, no links to Iago McIntyre's blog.]

jdallen_wa

Ostepop1000 - we've been around this before.

You keep tossing stuff out from places like ClimateAudit... and insist on adding meaning where it doesn't exist. You are familiar with this?

http://www.sourcewatch.org/index.php?title=Steve_McIntyre

We get you don't like Mann. We don't care to read your libels of him. Ironic, that the post referencing his name, which you seem to have reacted to, links to an article which discusses exactly the sort of attack you are making.

Leslie Graham

Ostopop
Please show at least some kind of credible evidence that Mann's hockey stick has been 'debunked' somewhere other than in your imagination.
And while you are at it you could show some kind of credible evidence that the dozen or more subsequent studies that verify and corroborate Mann's work have also been 'debunked'.
And yes, of course it is the pages2K project. I presumed that in your semi-professional capacity as a libeler of the original hockey stick you would have heard of it and obviously everyone else here has.
But actualy *citing* a notorious denier-blog and it's discredited creator as the source of your 'information' makes it perfectly clear that 'debating' with you on any scientific point or study would be completely pointless.
As jdallen points out - the tired old 'the hockey stick is broken' myth has been done to death for years and shredded to the point where it has reached a dropping consistancy.
How about you comment on something more relevant - like how JAXA shows the Arctic sea ice extent at a new record low for the time of year for example.
http://www.ijis.iarc.uaf.edu/seaice/extent/Sea_Ice_Extent_v2_L.png
Far more interesting than debunking ancient denialist myths for the nth time.

Neven

Yes, this is the ASIB, let's try and keep it about Arctic sea ice. PIOMAS has updated. It seems the gap has become slightly smaller, or so it looks to me after a first glance at the data. I'll have a post up tonight.

Susan Anderson

I will certainly look forward to what you have to say about the relatively warm Arctic and the winter slowdown. It's not hard to believe that the persistent inversion of warm and cold temperatures (sorry if I misused inversion, no doubt with a precise technical meaning, I just mean reversed from normal) would show up in the ice.

[You have, so far, been remarkably free from clutter, and McIntyre is one of the worst of a bad lot, a warrior for creating mistrust and delusion and hatred. Good job, though perhaps silence would be the best way to avoid further nonsense.]

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