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GreenOctopus

While not the record smashing year I and quite a few others were anticipating, this year has provided us with an incredibly vibrant series of events to keep expanding our education.

And though maybe not as exciting as the melting season, I am looking forward to observing the coming freeze season in its own way. Any fracturing events to witness? What will be our "goat's head" guiding us on the ice's drift when the remaining ice gets flanked by new ice? Maybe wili's "bear's head?": https://forum.arctic-sea-ice.net/index.php/topic,92.msg13122.html#msg13122

And will spring arrive early, keeping snow extent to a minimum; or will it be late again, and perhaps delay the ice's demise another year? There's a lot of physics to the Arctic that I'm beginning to appreciate and maybe it will keep me from expecting too much or too little. We keep questing for further understanding, but sometimes I think nature does just act in a way that wants us to keep quiet and just watch the show for what it is.

Werther

Thanks, Neven.
I'm off to Morpheus now, but I'll post here when I've got something worth while...

wili

I was surprised that not only was there a hole/very thin spot near the North Pole, but that it persisted for so long through the season. I would have though that it would have expanded steadily once it showed up, or that it would close in as all that loose ice in the area drifted in to fill up that space.

It is kind of like the mystery of why the goat head persisted for so long, but in reverse. Could it be that we (here on the blog, but also probably the scientists) don't completely understand the dynamics driving things in the Arctic?

A-Team

I'm starting to appreciate the full gamut of microwave frequencies -- a learning curve with it but eventually it starts to make some sense. The one below might have some predictive value for the week ahead.

 photo 10GHZ22AUG13_zps36420dff.png

wayne

Great article Neven, yes the North Pole "lake" was a precursor to this state of chaos mix between rotten ice and open sea. BTW There is nothing funnier than WUWT people laughing at a reality they can't understand.

"Could it be that we (here on the blog, but also probably the scientists) don't completely understand the dynamics driving things in the Arctic?"

Wili , yes if you are a model, not a scientist, unless he or she can calculate a million times per second. Scientists always can grasp and explore broad observational facets, and try to rationalize events. In this 2013 melt, many oversimplified the meaning of statistics without exploring further. However sea ice is a lot bigger than a pin hole, Eisenberg uncertainty principles are not applicable here. You rarely read, but from the people here , that 2013 melt is not what it seems, it was and is , in my opinion very extensive. Going back to my spring time research examples, I have discovered that it can be -20 C outside and sea ice can stop accreting. Cloudiness is not a friend of sea ice making.

Who said it was frozen at the Pole when there is so much open water there? Remember not to listen to this amateur.

Dan P.

I believe the image ascribed to me was from Chuck Yokota!

Here's another one from the thread:

N. pole is marked by a green circle 5 km in diameter.

wayne

A-team , at first glance: fantastic! it seems to be oblivious to clouds...

BTW NP looks more open than my last capture... Cloud cover has been a problem indeed. http://eh2r.blogspot.ca/ So most of sea ice reality has been blurred, fodder for dumb contrarians.

DavidR

I think this debate needs a reasonable definition of 'Open Water' at the pole. Is it a pond 1m in diameter or 1Km or 10Km?

I suggest a definition that says that open water exists when the North Pole is outside the sea ice extent boundary. While that may be a bit extreme it is at least hard for WUWT to argue with. (No doubt they will of course!)

wayne

DavidR, I'd never argue with the guys at WUWT, my time wasted there is less time studying. The open water by the Pole varies in size from 1 Km2 to 100 Km2, the best way to describe is how long the surface is ice free there, which is about 50% of the time. Ice moves.....
Neven's picture of the nuclear subs risen in leads, would not appear from the same satellite captures, these leads would barely show a dark line or dot, perhaps as a single pixel.

A-Team

Ouch ... the new Navy Hycom algorithm is way off-base. Operationally, a couple of stops past hazardous -- far better off with direct imagery. The old algorithm is being irrevocably decommissioned on 31 Aug 13 -- too bad, it had some good weeks.

The fade-out animation has 5% transparency increments. It is slightly posterized because of the gif restriction to 256 colors despite Floyd-Steinberg dithering. Hycom has 29.4% the resolution of 89 Ghz Jaxa and so had to be upsampled for the overlay.

 photo 22AugNewNavo_zps934d2ffc.jpg
 photo 22Aug89ghz_zps5a82e110.jpg
 photo fadeoutNavo5_zps48f5e511.gif

SouBundanga

Commented on this here, with some Arctic trivia thrown in:

http://blog.hotwhopper.com/2013/08/holey-moley-arctic.html

DavidR

Wayne,
I was trying to capture a concept where it could be stated that the North Pole is 'ice-free'. Something more than a temporary state caused by moving ice.

The proposal to make the statement only when the NP is outside the boundary of the SIE allows a reasonable probability that the area will then remain 'ice free' for the remainder of the melt season.

Neven

Wipneus just posted his sea ice concentration map based on Uni Hamburg data on the ASIF:

Werther

Neven, hi,

I accept that image presented by Wipneus for what it is proposed to reflect. The hard numbers of surface ice concentration based on a treshold of 15% per chosen grid area.

It should be clear that the actual ice conditions are different. FI the ‘Wipneus’/UB map doesn’t discriminate between the mesh-pack on the downward limits of the map and the swaths of rotten debris between the Hole and the ice boundary on the Barentsz side (mid-right).

If one isn’t aware of that quality-aspect, one could be tempted to not see much difference between this year and FI 2005.

And, although there’s still chance that the numbers may get closer to the ’10-’12 average, it looks like that quality-aspect will be the only argument against a supposed ‘recovery’ and a stance that the ’07-’12 records were random anomalies .

Werther

We have a relatively impressive range of SIE and SIA data since ’79. It is essential to continue assembling these data on the same basis as was done before. That 2013 may look pretty average in that range is unavoidable.

When the time comes, I think we could weigh any capacity in to expose the quality difference and understand the physical processes that led to this year’s peculiar situation.

noiv

Since the North Pole is a just zero dimensional point on earth it is probably safe to say it gets ice free multiple times per week, at least during summer.

Artful Dodger

Welcome noiv!

Are you this "noiv"?

http://www.youtube.com/user/noiv

Cheers,
Lodger

wayne

"Since the North Pole is a just zero dimensional point on earth it is probably safe to say it gets ice free multiple times per week, at least during summer."

Sure, lets say 20 years ago 1% of the time of a given summer time period, now a days 50%.....

noiv

Hmm, thinking again I'd say you can't put ice on a thing with no size, so the NP is ice free all the time.

That other noiv must be an identity thief.

TenneyNaumer

A-Team, who is responsible for screwing up the Navy Hycom algorithm? Why did they change it? It is just awful now.

Bob Bingham

Its too late in the summer for any obvious spectacular outcome this season but the chewed up ice will still be there. Next season these patches will be like first year ice. This problem has not gone away and the ice is very unstable. The flood of fresh water coming from Siberia will probably freeze quickly but what is it going to do to the Gulf Stream. It's a complicated and many faceted system.

Jim Hunt

Tenney - Strictly speaking the US Navy haven't changed "the algorithm", merely "the atmospheric forcing" of an unchanged model, if their brief pronouncements on the matter are to be believed at least. That's been forced upon them by the Navy Operational Global Atmospheric Prediction System (NOGAPS) being phased out in favour of the Navy Global Environmental Model (NAVGEM).

There's lots more about all this both on the forum and on the update 7 thread here, but the end result certainly doesn't seem to model the current reality in the Arctic very well at the moment.

Sam

Even more amazing. Look toward Ellesmere today from the pole. Tell me this year isn't stunning, and that the setup for next summers melt isn't unprecedented.

http://earthdata.nasa.gov/labs/worldview/?map=-405248,-607104,-143104,-442240&products=baselayers,MODIS_Terra_CorrectedReflectance_TrueColor~overlays,arctic_coastlines_3413&time=2013-08-23&switch=arctic

Neven

Sam, contrary to the hole(s) I think this is pretty 'normal', but to be sure you'd have to look through LANCE-MODIS satellite images from previous years (by changing the date in your browser's address bar).

Neven

The holes (big one north of Franz Josef, small one near NP) have become more clear on the Uni Bremen SIC map for the 24th.

Glacierchange.wordpress.com

I have been looking for holes or at least cracks in the whole of Storstrommen Glacier on the NE coast of Greenland, there are signs of impending significant retreat. Storstrommen

Glacierchange.wordpress.com

Northern sea route, it is amazing Russia has given out over 400 permits for ships to use the passage this summer. Business did not take long to respond to new opportunity

TenneyNaumer

Thanks, Jim!

Sam

Neven,

Far from it. I have been watching the ice since the first MODIS images were posted. There have always been cracks and polynyas, shear fronts and pressure ridges. But this is different.

I watched in horror as the ice pulled away from Ellesmere draining a lake system that formed on the ice annually and which had a unique ecosystem estimated to be at least 3,000 years old. I watched too along with all of you as the Northwest passage and Siberian Sea routes opened for the first time in recorded history, and then when both opened simultaneously allowing the first circumnavigation of the arctic sea, by a sailboat no less. And I have watched as we all have here as the conditions got worse and worse with the expected variations from year to year.

But the extensive fracturing of the MYI combined with the ice pulling away from Ellesmere and with large open areas and a sea of icebergs near and at the pole. This is new.

With the extensive and wide fractures, the ice no longer has integrity. Sure, there was shear fracturing before. And that led to massive ice ridges under and above the ice that submarines and ice breakers in particular had to watch out for. But this isn't that. This is different. The ice is pulling apart in all directions.

This year we are too late in the season for that to mean much. However, I see it as a harbinger of the next two seasons, the two seasons where we should see the end of the summer ice play out.

The annual vagueries and variations will no doubt confuse and confound us as they always do. But the path is inevitable.

Once the summer ice is gone, the consequences to atmospheric circulation should begin to kick into high gear. The familiar cell and jet stream system will likely break down as the energetic driving force disappears. What that will be replaced by is anyone's guess. We will very soon find out.

Then too, the diving flows of fresh water melt in the northern Atlantic have already begun failing. With that goes the driving forces for a large segment of the great oceanic circulation. That too will have massive global impacts. Precisely how that plays out we do not yet know. That too we will soon learn.

Jim Hunt

The "hole" on the prime meridian is visible today in Worldview:


Hans Gunnstaddar

Sam: "the diving flows of fresh water melt in the northern Atlantic have already begun failing."

Do you have a link for that information?

Sam

Hans,

I wish I did. I wish we did. There isn't monitoring of this that I have been able to find. About the only thing I can go by is he secondary indication, the huge reduction in Ice transport down the northeast side of Greenland. The cold fresh water comes from the ice melt. As the volume of ice transported goes down, it seems apparent that he diving flows of cold fresh water have to be declining.

Once the ice is gone in the summer, that flow will clearly be gone in the summer.

Neven

Looking at that image you just posted, Jim, I think that small hole near the NP is not going to get much bigger.

Chris Dickson

I followed neven's suggestion & compared the ice north of Greenland on 08/23/2012 & 08/24/2013. I had to rotate the 2012 pic because the projection on worldview has changed:

http://thingsiknowidontknow.tumblr.com/

To my untutored eye, right now it looks structurally much worse than last year, but with a layer of snow on top.

Jon Hurn

Is that fog or have we just lost NPEO webcam 2? http://psc.apl.washington.edu/northpole/

jbyrd

So; just so that I understand this 'extent' idea.
Given that 100 percent of the sea surface has a ratio of 15 percent 'frozen' and 85 percent 'liquid'. (I believe the phrase is 'at least'.) But if 85 percent is 'frozen' and 15 percent is 'liquid' then the 'extent' is the same. (The 'more' side of 'at least'.)

Is this the classic 'can't see the forest for the trees'?

The forest is right there in front of us though. Take a look at the lance-modis arctic mosaic. Pretend you're Dr.Dolittle and just click on it. Blow it up to 250m resolution. See all those sort of circular 1/2 inch or so sized white circles? (at least on my 19" screen) Those are ice islands 10 to 15 miles across. They didn't get round by bobbing up and down in the sea!
If one clicks on either the northeast or north west Ellesmere Island sector today (8/25), they can see an amazingly clear view of the complete fracturing of the ice pack, which appears to be the source of all those 10 mile across (75 sq mi) ice islands.

Of course, I guess we should keep in mind that the amsr2 shows southern lake Michigan at 30 percent ice cover and the NOAA RTGSST site shows that the SST of southern lake Michigan is in the low 70's F.

Larsboelen

Can't help but find the Greenland ice movements during the last week nothing less than spectaculair: http://youtu.be/PZDSMe1zHbA

Jim Hunt

By special request, an animated GIF revealing the increasing "Barents bite" over the last 5 days, assembled from the University of Hamburg's 3.125 km AMSR2 concentration images:

It stops after a bit. Try opening it in a new tab or window of its own for an action replay.

TenneyNaumer

That's a really cool animation, Jim!

Well, the Navy may have screwed up Hycom, but have y'all been keeping an eye on SSSs?

Some major changes over the past few days:

http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticsss/nowcast/sss2013082518_2013082600_036_arcticsss.001.gif

Paul Klemencic

The big polynya between 75E and 120E should grow substantially this week. I thought it would fill in resulting in a big low concentration area in the pack, but now this doesn't seem likely. Today it increased in size, and tomorrow the winds shift. Jim Hunt, if you are reading, post your gif showing the last week ending today. Then get ready to start a new one.

HP should extend out toward the pole over at least the next four days, and the wind over the polynya should begin blowing toward the Laptev and the N. Siberian Islands. This wind should push the ice east of the polynya toward Siberia, and the width of the polynya could easily grow 50-100 km over the next four days or so. Then the forecast shows the HP completely blanketing the NP without strong winds for the next 4 days or so (but this far out the forecast is more likely to be wrong than not).

In this case, the last week plus the next two weeks will show the most interesting ice pack action this season.

When will the normal ice drift resume? If we finally get a move toward the Fram, the big holes will drift right over the pole, and will result in not only low concentration (<50%) ice at the NP, but even open water!

Paul Klemencic

Ouch, I shouldn't post late at night. Disregard the portion of that last comment regarding wind direction. The wind will be originating in the Laptev and blowing into the ice pack, tending to push the polynya toward the NP. Eventually the HP is expected to settle over NP (next weekend), and the clockwise rotation will push the edges of pack toward the Fram, but there won't be much wind over the central portion of the pack.

If the HP had set up over the Canadian Arctic Archipelago, then we would have had a much more interesting scenario.

Jim Hunt

Leaving AMSR2 animations aside for the moment, it's well worth checking out Worldview today and having a good look around. Much of the Arctic is visible, albeit through thin cloud over large areas. There's a very pretty swirl of cloud on the Pacific side. Opposite that there's lots of holes, both large and small. Here's a quick preview:

Please note the change of scale compared to the aqua tinted image Neven posted above.

NJSnowFan

It has been awhile since I posted on the tread.
I have been doing some research on effects of Ice Breaking ships on the Arctic Ice. Seems as more larger Ice breaking ships have started Crushing the ice the ice has been declining.
The hole that is not far from the N pole is the location that The Worlds largest ice breaker was in at the end of July. You make your own judgement on if the ice breaking ships are causing serious melting during the summer months. One I came across the other day.
https://mobile.twitter.com/NJSnowFan/status/371845684753756160/photo/1

NJSnowFan

Here is is an Ice Breaking ship near Antarctica. You can see after the icebreaker crushed the ice it showed up on the satellite. https://mobile.twitter.com/NJSnowFan/status/372384471711891456/photo/1

Call me a Troll or what ever you want, ice breakers are like a Dozer to a forest during summer.

Doug Bostrom

Re Jim Hunt's August 26 18:41 post, for those of us less focused on numerical reports and more on periodically taking a gander at images that sequence is nothing short of astounding. Wind your mind back 10 years and think how you'd react if shown such a thing as a prognostication.

Exactly what is an ice-free NP? Doesn't matter how it's defined; the NP is already cooked. Not to say that a definition has no importance, just that the broad strokes of the picture are already painted.

NJSnowFan

Last one of Many Ice Crushing Ships I will post in the Arctic. USCGC Healy, tracks from last 8 years. Each year in order from 1 to 8 every 8760 hours. This is only one Ice Breaking Ship. There are fleets of them crushing the ice.

https://mobile.twitter.com/NJSnowFan/status/372415421468512256/photo/1

Watkin M

Hi. Hope you don't mind me briefly unlurking, but I've also been fascinated over the past two weeks by the dramatic fragmentation of the multi-year ice lying between Greenland, Ellesmere Island and the pole.

As far as I can see from MODIS, this did not happen to anything like the same extent last year, despite the fact that 2012 was significantly warmer in the area - illustrated by less snow on land, more ice melt in the north coast fjords, and more open water immediately adjacent to the coast.

In 2012, MODIS does show multiple fractures in the region, but the resulting flows are more like 100km across - except near the coast. And in 2012 there were large melt ponds visible into September, which to me suggests the ice has largely retained its integrity. This year, especially to the north of Greenland, the ice has broken up into thousand of smaller flows, typically in the region of 1km to 10k across. No sign of melt ponds, but plenty of open water.

Does anyone have any idea as to why this might have happened? PAC2012 didn't smash up the ice in this region last year - and this years collapse didn't seem to coincide with a storm. In fact the weather was clear for much of the period - presumably indicating light winds.

I also have no idea if this matters? The big questions to me is will a larger number of smaller flows be ejected out of the Fram Strait more rapidly - or would large pieces of ice move at the same speed?

Hans Gunnstaddar

Watkins - Does anyone have any idea as to why this might have happened?

I wonder if the traditional viewpoint is we expect changes to coincide with a particular event, when in reality big ice drifts of MYI probably do not respond immediately, but instead are delayed.

Martin Gisser

Watkins, there was this spectacular fracturing event in spring (meanwhile storied in early c21st art history as Narcissus' mirror cracked from side to side). I guess the cracks went from young FYI well into the old MYI. That's what you see. We are lucky the weather was bad this summer. (Still, the state of the minimum ice seems to become something unseen. Do the numbers make any sense this year?)

wili

With the large snow melt on the Siberian side, there was a lot of very fresh water over there that froze solidly when it got far enough north.

I think that goes a long way to explain why we seem to have relatively solid ice, then total slush and holes in the middle of the pack, then old, more or less solid ice again near the CAA this year.

Marktough10

Hi NUSnownFan,

The best article on ice breakers, I've seen, is at the NSIDC's Icelights section - here's the link and an extract below.


http://nsidc.org/icelights/2012/04/12/are-icebreakers-changing-the-climate/


Meier said, “In late June, when the sun’s energy is strongest, the total sea ice extent is around 10 million square kilometers or 3.9 million square miles. An icebreaker cruising through the ice for 1,000 kilometers (620 miles) and leaving an ice-free wake of 10 meters (33 feet) would open an area of water 10 square kilometers (3.9 square miles) over the entire cruise.

In contrast, the Arctic sea ice cover decreases by an average of over 9 million square kilometers or 3.5 million square miles each year during its melt season—an area larger than the contiguous United States. In total, researchers estimate that the number of icebreakers traversing the Arctic at any given time is usually less than three. So, Meier said, “The actual contribution is miniscule—only one part in a million of the total ice cover.”

Me again....

Sea ice reduction is man made but it's not the ice breakers causing the holes - it's humanities reliance on Fossil Fuels. It's a complex, beautiful, intriguing arctic out there but the reality is that CO2's tearing it shreds. We need to understand the detail but the big picture is oh so very clear.

LRC

Watkins. And in 2012 there were large melt ponds visible into September, which to me suggests the ice has largely retained its integrity.
Based on what happened to it this year and that fact that what has happened this melt season does not seem to explain everything, I would say the above statement must then be false. It APPEARED to retain integrity would probably be better. I would suspect that the melt pond drain through the ice changing the structure of the ice enough that when hit this melt season made it break all apart.
A lot of theories about ice are based on what we see via satellites and we tend to forget eye witness accounts, such as statements by those drilling core samples and finding whole sections useless do to melt, or those on ships who see whole sections of 'safe' ice disintegrate into slush from wave action where it should not be effecting, or local indigenous peoples who keep on telling the 'experts' that the ice is in trouble and they can no longer trust or read it.
Granted, eye witness accounts are almost impossible to quantify scientifically, but if we do not include those statements into how we evaluate the true conditions then we will get it wrong.
As an example. http://www.iup.uni-bremen.de:8084/amsr2/arctic_AMSR2_nic.png for the last while keeps on including ice in the Great Lakes. Now it is not always the same area either. This could be because of the angle of reflection is giving bad data. Could be type of cloud in the area. I do not know. All I do know is that at this point in the season there is NO ice on the Great Lakes. If it is getting bad data there, where else is the data bad and could it be that there are bigger holes then what the satellites are showing? As has been stated many times, it has been a very cloudy melt season and we can not get a good visual idea of the true conditions of the ice. Not only that, there are fewer groups in the Arctic this year (as opposed to the last few years) giving eye witness accounts of what the ice is like close up.

Marktough10

Hi LRC,

I've enjoyed reading your posts - as a bit of a lurker I always appreciate those who have an opinion and are brave enough to share. Too many of mine are proved wrong to quickly to post regularly but hopefully I'll improve before the ice is gone.

On your post - I totally agree with ice in the Great Lakes (not good) and what about Lake Vanern in Southern Sweden - it's 80% plus ice concentration all year. I've swum (not skated) in a few Swedish lakes in Summer and they can be surprisingly warm - so I expect another anomaly.

There is an explanation over at the NSIDC

http://nsidc.org/icelights/2012/07/18/do-satellites-sometimes-see-ice-where-there-isnt-any/

It makes sense but can someone please update the masks occasionally? It's just another excuse for the fake sceptics to have a go.

Really agree that we need more data and field work fed into the algorithms. I don't feel the ice is structurally sound on many levels - polnyas will be a big part of the 2014 melt and perhaps 2013 still has a few surprises for us in that regard.

A whole lot of holes and a whole big problem for our kids.

John Christensen

@LRC,

Yes, evewitness accounts have value, but the challenge is also that it invites to cherry-picking of prefered situations to support views that cannot be scientifically supported.

If you take the USCG Healy:

This ice breaker is roaming the Beaufort Sea and had an 'Ice Liberty' party on an ice floe on 8/23:

http://www.uscg.mil/pacarea/cgchealy/aws13/img/20130825-IceLiberty.jpg

http://icefloe.net/uscgc-healy-track-map

The track map shows that the air temperature was -4C and the water was -1.1C, and comparing with CT maps it looks like the Beaufort Sea this year so far has the lowest anomaly since 2003, and ice of the thickness and quality at this exact location probably only were seen in 2009 and then back in 2005 or earlier.

While local data certainly provides perspective and adds to the overall knowledge, it is extremely challenging to make wider deductions from this, especially since we know that what is going on in other areas (E.g. the Hole near the Pole) is very different from the Western end of the Arctic.

Gerhard Trausner

It now come the days where the sun can appear directly underneath the clouds. The long-wave
Radiation will keep the ice and the water warm. It is more convective clouds
produce.
It is the final of the melting season.


Another aspect is the widely scattered ice.
If the new ice is lower, the wind has a good attack. The drift is stronger in the next year. The new ice is broken at every slight storm. The columns must be new ice forming. From year to year more ice must re-form in the winter. Were there earlier in the
September in the Arctic Basin (about 7.5 mil sq km) for about 6mil sq km ice, so there are in recent years, only 2.5 to 3 mils sq. km.
This means it must be there now every year
Produce three times as much ice new, than before.
That is, it drops 3 times as much water in depth, what needs to be replaced again. The termohaline circulation is stronger. And the Barents Sea warmer.
http://www.seas.harvard.edu/climate/eli/research/equable/ccf.html

Watkin M

LRC. "It APPEARED to retain integrity would probably be better".
Hope I am understanding correctly, but you seem to be suggesting that there is a micro scale structure to the ice that isn't necessarily visible by satellite using either IR, MW or visual imaging? Eg apparently solid ice may actually be "rotten" in some way?
Looking at 2012 MODIS again, it strikes me that that some of the ice I was assuming was continuous "multi-year" ice might actually have been a matrix with more or less scattered floes of older ice originating from the 2011 melt season embedded in first year ice from winter 2011/12. First year ice is presumably the weaker element of the matrix, effectively creating fault lines throughout the pack which fail when stressed beyond a critical threshold.
If this is true (and just hypothesising here) in 2013 the underlying structural strength of the pack would reflect the record melt of 2012. This could explain how the ice could fracture to a greater extent across a much wider region during a cold summer which also lacked a major late season storm.
Last question before I return to lurking, how solid are the ice depth and density assumptions used to calculate PIOMASS and other volumetric measures? If the multi-year pack is significantly comprised of thicker, denser blocks of old ice embedded in newer thinner ice, would the algorithms used to interpret satellite data actually pick this up in the average? Or could the changing state of the pack be causing over (or under) estimation of thickness and/or mass?

Werther

The quest to document ice quality took another evening over my CAD screen.

This ‘leopard-skin’is the digitized SE quadrant with a radius of 50 km on the North Pole today on MODIS.

 photo Areapolarquadrantsmall_zpsc53c0ab6.jpg

For 27 August CT showed this at about 65-70% concentration. What UB supposes for 27 August is hard to tell, because their Pole-hole is large (radius about 100 km). But both to the W and E adjacent swaths are yellow and green, also suggesting 65-70% concentration.

As you can see, I’ve digitized surfaces on obviously unified floes. As their reflection fades over about three pixelwidths, the edges are arbitrary. That’s what should be kept in mind when interpreting the CAD-numbers.

What did the program find?

The area covered by the quadrant is app. 1964 km2. There were 177 surfaces, the smallest just about pixel-width covering about four soccer-fields. The biggest were undivisible stretches but obvious thick packed rubble.
When these two swaths are set apart, the largest floe is app. 70 km2, the average of the lot is under 4 km2.

CAD found 982 km2 ice, about 50%.

As the total edge-length is app. 1440 km1, the possible uncertainty through the fading can be fathomed. Given the half of the fading zone, it could be as much as 500 km2.
I presume the fading zone might feature small rubble, nilas e.o.

The area that is open for sure is at least around 500 km2.

When would have been the last time to have shown so much open water over a relevant distance?

PS another representation on the Forum ‘When will we see open ocean at the NP?’-thread.

seattlerocks

The hole, the vast areas of low-concentration ice... Honest truth, 2012 was far worse because there was NO ice there, hence no place for holes no breaches between non-existent ice masses. OK, strictly speaking, open sea did not get so close to the NP from the Atlantic as it does now, but will that really matter?
Big ice recovery this year I believe, who knows what next. Will be fun to watch (may Neven abide).

wayne

seattlerocks, no, its not a recovery, its scattered sea which was caused by contrarian winds, the end result may lead to a faster refreeze, but we are not there yet. Saying its a recovery is like dumping ice cubes in a full bath tub and spreading them all around, see how it covers more area as opposed to leaving them in the freezer tray and make it float.

LRC

@ Watkins: I was thinking not only at a micro level but as the sheet as a whole. Think of why those who climb glacier fields walk with poles. Part of it is to help them climb without slipping, but the big reason is to probe ahead in case there is a thin layer covering a deep crevasse. You can not tell whether or not that thin layer exists until you actually punch through it. Similarly, thick MYI Arctic ice should in theory be very dense clear ice when viewed in the light. On the other hand I believe the majority of thick ice now if you where to take a core sample would be very fractured up to and including consistency of compressed slush. The question is, can mircowaves tell the difference? Or can they only tell you how thick it is? Seeing as they can get fooled by the right cloud conditions into interpreting it as ice, I can not see that they can actually tell the difference. From the view of looking at Arctic ice that difference is huge. Solid dense ice can take a big beating and still hold together. The evidence of a great deal of the new thick ice seems to me shows the structure of the ice is very weak in which case small weather changes can turn what appears to be a solid MYI sheet into a shush pond very fast.
There is a growing group of scientist studying the GIS that believe the same problem exists there and that the situation there is very dire.

LRC

@ Marktough10: Thanks. I like thinking way outside the box and try to express myself, because for me that is how I learn something new. just regurgitating the standard ideas just means you can repeat what you have been taught, which is not always right.

Robert S

@LRC: Yes: I've been spending (too much) time flipping back between 2012 and 2013 images, and while there are big areas with ice that were clear in 2012, there is also so much fracturing and disintegration in areas that were relatively unfractured ice last year. So even though this is a "lower" melt year, there has clearly been a major strength change in the ice, resulting in everything from 20 km pans to areas with no discernible structure at all. I seriously suspect that PIOMASS can't deal with this condition, and that this year's melt is actually not as much less than last years as we think. It's pretty clear that ice extent is less and less useful as a measure, and that all of our other measures are also questionable. Time for someone to come up with a new metric...

Sam

This isn't the right place for this, but then I don't know where the right place might be.

In thinking about the various differences this year and trying to puzzle out causes, I keep going back to the atmospheric influences.

First I look to the jet stream and the changes there, and about how the two jets seem to be merging.

http://www.atmos.washington.edu/~ovens/wxloop.cgi?npole_h250_wind+/-168//

But then, I also keep thinking there is something else controlling. The folks at the University of Washingtin have some amazing tools for trying to sort out what may be happening.

http://www.atmos.washington.edu/~ovens/loops/

In particular, I think the Rossby number must be important (or the related vorticy).

http://www.atmos.washington.edu/~ovens/wxloop.cgi?h500_vort+/-168//

I also think the solar minima we are currently passing through is key (on the decadal not yearly scale).

I wonder whether anyone has a good tracking site for telling whether the atmosphere is rising or falling, to get some idea whether the polar and Ferrell cells may be merging.

The plots of pressure height divided by vorticity in particular looks to be important fir the fracturing of the ice north if Ellesmere.

So, thoughts anyone/everyone?

Sam

Sam

Apologies... The Apple i-whatever's seem to just love substituting i's for o's. e.g. "if" for "of" and "fir" for "for"....

Jim Hunt

seattlerocks - What do you make of the open sea getting so close to the NP from the Pacific?

Will that matter?

seattlerocks

Jim, yes I see your point and yes, I admit, it will matter, it obviously looks terrible compared to 2009-2010 even, so this is not a comeback to previous normal. But still, when you compare this with last year images... Fragmented ice, but a good deal of extension. We'll see what happens with it next year.

seattlerocks

Wayne, to clarify my opinion as I said to Jim, this does not look a recovery to pre-2007 normal, not even to 2009 or 2010 when I see the sat images form those years, and compare the "health" of the ice cap in terms of cohesion, etc. but cannot deny looks much better than last year, that's all.

seattlerocks

And sorry for the "bombarding": I mean recovery not only in quantitative sense of extent & area, I mean it also qualitatively; there is ice where it was absent last year.

However, there is a difference in quality that seems interesting to me: the compact ice pack, as extended as last year, shows a different shape, like being crushed against the Canadian and Greenland coasts... will that matter in one sense or another?

John Christensen

@Jim,

To be 'fair' to the ice this year, very nearly the top half of your image was just open water with no ice last year, so there was no pack to show a similar split, as you see on CT compare:

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=08&fd=26&fy=2012&sm=08&sd=26&sy=2013

Equally, I would not extend any comparison of overall ice condition or health back beyond 2012, but would agree that overall the ice does seem to have recovered somewhat from the summer of 2012; more ice, larger area and extent, but also a further degraded structural integrity this year compared to 2012.

But between two evils, structural integrity loss and area/extent loss: Yes, we clearly observe the continued deterioration of the Arctic ice structural integrity, but from a climate change perspective, I would rather see integrity go down than area or extent, due to the increased heat influx caused by decreased ice cover during summer months.

This does not change the end game, but would seem to possibly delay the climate impact somewhat until we get there..

Jim Hunt

@John - Sure the remaining ice was configured differently last year. Here's another "video" covering the same few days from 2012:


Since the Hamburg 3.125 km AMSR2 wasn't around last year that was generated from the Bremen 6.25 km AMSR2/ASI images.

From a climate change perspective isn't something like an "integral of albedo" a more relevant metric than the ones you mention? How is that related to the combination of integrity/area/extent, and what difference (if any) might two packs instead of one make?

@SeattleRocks - I agree things look rather "different" this year compared to last. It's not yet clear to me that they are "much better".

Jim Hunt

A clear view through the clouds this morning confirming the picture painted by the microwaves yesterday:

Note the difference between the

Jim Hunt

Whoops! Between the "first year rubble" at the top and the "multi year pack" at the bottom.

Patrice Monroe Pustavrh

I've been checking rubble via MODIS and it seems to mee, that at least in some areas, ice has begun to reform ( http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r04c04.2013243.terra.250m ). I must admit this year's season has been really, really weird, as we had really much more cyclonic activity and much colder weather than many of the seasons before. But, anyway, extent might still go below 5 mio km2 and melt season is not completed yet, at least in not being close to pole areas. But as it seems now, even very cold year can only "restore" ice to a point where it is still lower than any year before 2007.
And there is another thought that crossed my mind, and if somebody can provide more info, it would be very interesting: Can we expect during the disappearance of Arctic sea ice greater variability between year to year ?
(P.S. I am aware tamino has already shown us, that the difference between max and min extent has increased).

Pjie2

(add the 7-2-1 layer to see it best)

wili

"the difference between max and min extent has increased"

Good point. Even if there is no more melt this year, we will have lost more SIA over the season than we did in 2007 (if I did my maths right).

I(t strikes me that not only the low extent and area at minimum last year, but also the slow re-freeze in particular may have been a factor in this year's failure to reach a new minimum. There was a lot of time through the fall and early winter when a lot more water than nearly any other year was exposed directly to the cold, sunless winter night. Lots of heat could have been lost from the system during all that time.

Sam

Quality is the key now.

Despite this being a bizarre rebound year, the ice quality is crap. The standard indexes of area and extent have become highly deceptive.

With the extensive fracturing and thinning of the remaining ice, and that ice pulling off Ellesmere, next year and the year after should be breathtaking.

So, now we wait for the inevitable.

Russell Seitz

While efforts to name hurricanes after Senators and Representatives seem politically foredoomed , Congressional staffers and other dogsbodies may be fair game , and there are plenty of phenomena to go around!

Jim Hunt

Pjie2 - I'm with Patrice on this one. Use Worldview 7-2-1 to examine closely an area that's been largely cloud free for a few days.

On the 28th there's certainly some cloud around, but other than that the polynyas look ice free. Stepping through until the 31st reveals some paler structure appearing in the polynyas. New ice seems the likeliest explanation to me.

Sam - I'm with you that area and extent have become highly deceptive. What might be an improvement though? How do you attach a number to "ice quality"? How might one go about measuring and/or modelling the vulnerability of the ice visible via my link, this year and/or next year and the year after?

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