If you look at GTW's link you'll see that , by the time is swashes over that coast, it did have height above tide levels and it will have taken the form of 4 or 5 big waves. The waves will have broken beyond the ice cover (run up the beach) but washed back on top of the ice (striping the snow cover and leaving just ice).

Today is the start of the spring full moon and so a similar height change will work over the whole basin so we should look at the ice integrity on Monday to see if (any) changes have occurred to the levels of fragmentation?

I couldn't decide if a residual tsunami of perhaps 10-20cm was anything unusual but you may be correct.

Anyway, tentatively it looks as if we may have peaked in terms of ice extent.  We achieved 13,887k on 8th March, since when the figure has fallen back to its latest 13,818k.   Based on recent years the value could still increase for another week or so but is likely to remain 2nd lowest in the recent record.

Hi Guys!

I don't think (?) it would take more than GTW's 10-20cm swell to wash off the snow cover on a back swash? With the 'snow' cover gone we'll find the albedo lowered and melt hastened?

http://www.woksat.info/etctc20/tc20-1131-f-grn-n.html

So , any new 'leads' from the spring 'supermoon'?

http://nsidc.org/arcticseaicenews/

Still high enough to cause us ice max. Four! So here we  go for the melt season.

Lower than 07' by ice min I'd guess.

That's puzzling as those values are different to the ones on the IJIS site.

According to that site the maximum was a day earlier and was the 2nd lowest, just ahead of 2006.

Interesting swirl around central arctic (viewed on Cryosphere Today 03/23/2011), looks like ice may already be weaker in this area?

Hi FredBear.(and welcome)

I was wondering about that swirl myself lately.
It doesn't show up on the comparison screen from Cryosphere.

Worth following for a while.

Things can change up there from day to day.

Woksat or Rapidfire Sat will bring you closer on current conditions.

You will need to know your geography or orienteering for these interesting sites.

The freshwater content of the upper Arctic Ocean has increased by about 20 percent since the 1990s, according to a new large-scale assessment. This corresponds to a rise of approximately 8,400 cubic kilometres and has the same magnitude as the volume of freshwater annually exported on average from this marine region in liquid or frozen form.

from -

http://www.sciencedaily.com/releases/2011/03/110325111901.htm

We all know fresh water freezes more easily than salt water and we also know that salt water ice melts earlier or at lower temperatures than freshwater ice, so, is this extra freshwater another feedback mechanism conducive to ice sustainability?

That's an interesting article.  I think the conclusions are rather different from the one you are offering?

Firstly, the increasing levels of freshwater have been building up at the same time that ice has been reducing. I would have thought that you might conclude logically that the rate of ice loss would have been even worse without this fresh water. To that extent it is indeed a feedback mechanism but it doesn't appear to be stopping the melting, merely - perhaps - slowing it a litte?

Of more concern perhaps is the effect of freshwater outflows on the sinks that are a critical and delicate part of the great ocean conveyor system.  It was suggested some years ago that increased river flow into the Arctic Basin would lower the salinity and might impact in this way.  Couple that with the rapid ice loss from the Greenland ice sheet.

Yes, removing a key component of the mechanism for moving heat and moisture away from the Equatorial regions would have potentially profound effects.  As I understand it, around the North Atlantic (NE US, NW Europe) we would see a offset of the warming from AGW whilst the heat would be held nearer the Equator.  This has been modelled and I recall that rainfall reduces markedly in some parts of the world.

Who knows?  But it is one example of why I keep saying that we are unwise to be tampering with such a complex system (the global climate) when nobody knows for certain how that system will respond to changing inputs.  Tipping points and non-linear responses are, I understand, typical of complex systems.  "I told you so" will not be much help if we blunder into one.

I'm sure there was recent research showing that the sinks (of NE Greenland) had returned back to their 'normal' patterns?

As for the 'freshening of the Basin' there's a lot of melt water (from 'old ice') and lots more outflow from the Northern European/Russian land masses. As to the 'shakedown' from this surface freshening? as long as it doesn't involve 'dark' algal blooms we are probably just playing 'swings and roundabouts' with earlier melting/freezing timings?

I did give this some thought earlier.  Unless I am missing something surely the melt water from old sea ice will be saline?

A lot of the salt separates out and sinks when sea water freezes.I have a short explaination linked below.

Sea Water, Freezing of - river, depth, oceans, temperature ...

As the ice ages it sheds more of it's 'cargo' of salt. the old Paleocrystic was virtually salt free. We now only have young ice so it sheds salt as it forms and traps pockets in it's structure.

That said it may be the final melt out of the old ice that has played it's role in the 'freshening we now see (along with the uptick in discharge from the land).

Another thought is the 'layering' of the surface water of the Ocean. If we are seeing a more active surface layer ,mixed by swells, then we may see this 'new' top layer trapped above the remnants of the old Halocline (now only remaining at depth)?

Thanks AIMSIR, that was helpful.

As I'm sure you've guessed, the whole sea ice/saline system is a lot more complicated than the above,but it's a start.

I've found that most things in life are much more complicated that you expect.  I find sometimes that I go through a process starting with thinking I understand, discovering I don't and then disappearing into confusion until the fog clears and I begin to understand properly.

It's very much the case here.

An encouraging late growth spurt
http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Extent_L.png

Yes, but only for one day and not at all unprecedented at this point in the cycle.

Last year there was a spurt of almost 150,000 sq km over 3 days at the end of March and close to 100,000 over 3 days in 2009. Similarly in 2006.

Gray-Wolf suggested that the late peaking last year was due to the ice melting and spreading out - remember that the definition of 'ice extent' is an area with at least 15% of ice.  I think it is quite possible that the same thing might be occurring but we won't know for a while.

If we check our MODIS images we can see just where this 'stall' is founded. Both the peripheral pack and the coastal/peripheral ice of the basin and fragmenting and drifting.I suggest that to not see 'growth' in extent means 'losses' as the ice is only covering the same surface area (min 15%) yet there is visibly 'less' ice. By May the 15% or more rule will swing the other way with record drops in ice level. Driven not by melt alone but drift also taking all of the peripheral ice beyond the 15% min so rendering the pixel 'ice free'.

The other thing to note is the high AO+ve (forecast to get even higher??) This may not aid transportation (as PIPs shows) but ,come late spring, will result in a lot of sunshine across the basin. As we saw last year even paleocrystic ice succumbs to warm sun and warming waters (South Beaufort sea last July) and how much sub 2.5m ice do we have out there this year (sub 2.5m young ice will melt out over an 'average' season.....before the decline of the nineties and noughties this made up the summer melt for the central pack).

http://topaz.nersc.no/topazVisual/matlab_static_image.php?action=NA_ARC_NWA_Function&file_prefix=ARC&match_date=20110224&depth=0005&variable_name=hice

A further thing I have noted from MODIS is the lack of over-ride/pressure ridging going on? Ice appears to just break when ramming another floe leaving a mass of smaller fragments instead of 'healing' the lead??? If this is true then we will see a different July/Aug this year with some of the fastest melt rates ever recorded (I believe). By late July we will know if we are headed sub 4 million and have a feel for just how low the final min will be?

I am happy for the folk seeing 'positives' in this. Last year it was the very high extent and NH Snow cover. Those folk are now more careful about declaring signs of recovery from such augers. This year it may be the stall as the ice collapses around it's edges and melts whilst spreading out. Next year they will be more careful of such after seeing what this type of 'start to the melt season' brought us?

EDIT: The 'ice Bridge in NARES is now collapsing (2 weeks before I suggested?)

http://rapidfire.sci.gsfc.nasa.gov/realtime/single.php?2011091/crefl1_143.A2011091204000-2011091204500.250m.jpg

It was in place at 10:30 GMT yesterday but failing by 17:30GMT. Seems there may have been a lot of 'drift snow' from the glaciers to the East giving the impression of a thick ice plug but ,in fact, just a lot of wind blown snow. If it's broken and cleared by this time next week I'd 'worry' about the speed of the melt/collapse within the Archipelago itself?

Which brings us to the Candian Archipelago. We saw the last of the 'Channel Ice' melt out there last year so it is comprised of ice similar to Nares. If it breaks up and collapses before June then we'll inherit another drain on the thickest/oldest ice in the basin (the 'thin white line' along Ncoast Greenland/C.A.). The clearing of the channels also allows the spread of warmer waters around the Archipelago.

Things will start to happen fast over the next 6 weeks and give us a better 'feel' for the season ahead!

Superb image Gray Wolf.
The Petermann glacier tongue looks in good condition.

Mabey I am one of those hope er's.LOL

Eitherway ,A superb image.

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

Quite a drop over the past 2 days? (164,000)

Hope this is just compaction and not the start of the peripheral 'float off' of ice beyond 15% per pixel cover?