Sea Ice News – Volume 3 Number 8 – meltwater hues, or blues?

WUWT commenter Caleb writes on 2012/07/20 at 7:53 am

Check out the “North Pole Camera” on the WUWT “Sea Ice Page.” Both Camera #1 and Camera #2 show lovely summer weather, and patches of melt-water atop the ice.

One problem has been that this melt-water can appear to be open-water, in the radar-eyes of a satellite. Apparently liquid does a great job of absorbing radar, and the radar got no echo even if the water was one inch deep rather than one mile deep. Has this problem been addressed?

Also camera #1 shows a neat pressure ridge on the horizon to the upper left. That little mountain wasn’t there a month ago. Remember that nine tenths of it is under water. Quite a “Volume” of ice is in a small area, there.

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One wonders is that top of the ice meltwater issue is part of the reason why the current Cryosphere Today image looks so different than on 2007:

While there is a lot of cloud cover, breaks in the clouds in the visual satellite imagery from AQUA Arctic composite shows those areas with some open water, note the magenta arrows I added. Greenland is at the bottom left, in bright white:

NSIDC doesn’t seem to be that much different than 2007, but it only shows 15% or greater extent, so the “red soupiness” seen on CT imagery won’t show up:

Or, we may be witnessing the prelude to a very large melt. Only time will tell.

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pat

I suspect we will see a large melt followed by a normal winter.

Note that the ice extent is near the average until the sun rises sufficiently around the start of may. Clearly an albedo/insolation effect.

Rob L

Melt water pools of any significant size on the ice would quickly drain through cracks into the ocean. If it is big enough to see by satellite at 10’s of meter scale than it is almost certainly open sea water.
It is possible that radar systems could tell the difference too. There would be a height difference, for melt water over ice compared to sea water. A radar system would probably do the best job of assessing the open water extent and ice thickness simply by looking at altitude of the surface. It would see through clouds too.
Not sure if any of the sat sensors are radar, but seems pretty likely given everyone’s interest in assessing ice growth/loss over icecaps and sea.

noaaprogrammer

Notice the exposed land in the sat-photo of northern Greenland. Another statitstic that could be used would be to determine the amount of ice-free/glacier-free land in northern Greenland above a given latitude.

Interestingly, the Northwest Passage does not seem to be too keen on opening up.
http://www.ec.gc.ca/glaces-ice/default.asp?Lang=En&n=2D414464-1&wsdoc=61BCCE40-2248-11DF-9BC2-B9D43796A02E

Tom in indy

What’s the temperature difference between night and day? (Once “night” returns.) If meltwater freezes at night then you could compare daylight and night satellite measurements to calibrate the satellite measurements?

Poriwoggu

Check out the ice thickness:
http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim365d.gif
What is really interesting is there is less ice but much more thick ice than last year.

SteveSadlov

The “occluded fronts” hanging off of the gyres are areas with massive compression and a good deal of verticle relief. The central portions of the gyres themselves are similar. The grand gyre poleward of Greenland looks utterly mountainous. No way that will melt.

Gary

Hang on geriatric ice!

Some European

Thanks for the update. Would it be fair to say that Arctic Sea Ice is currently tracking around record low levels both in extent and area? A previous commenter points out that there’s an albedo feedback at play. It seems that open waters around summer solstice would absorb more heat from the sun. So, this should add to the total heat content of the oceans. I wonder whether there’s a sort of fingerprint to single out this effect compared to other parameters influencing the ocean’s heat content, such as ENSO, solar radiation and infrared absorption.
Maybe a working scientist can answer the questions raised by the blogger. (Or maybe the blogger could find the answers in the literature?)

If the sun was to set there tonight, I’d bet there would be no melt water by morning! clear sky’s and freezing temperatures at night time are ideal conditions for ice growth.
It makes sense that Ice growth will take a few years to accumulate again after a prolonged warm period the same way that we know that the loss of Arctic ice took years before it began to melt after we entered into a warm period.

RHS

Rob L,
I would suspect the satellites in use have resolution better than 10’s of meters. NOAA (not sure why) is the branch of the US government which license’s satellites and what resolution can be utilized. I think most of N. America for US companies is .5 meters and I would expect the government would allow their own satellites to go to that resolution. The US based companies (DigitalGlobe & GeoEye) supply satellite photos to GoogleEarth at pretty respectable resolution.
I guess the point I want to make is, without knowing the resolution, type of imaging (radar or light) and the analysis used, it is hard to tell how anything is interpreted.

mogamboguru

My Eyeball Mark I sensor has realized a change in the rhythm of summer-melt vs. winter-freezing in the arctic ice cover insofar as the maximum area covered during winter seems to have returned to average (pre-AGW) levels over the past 3 years, while the ice-cover during the height of the summer-melt seems to keep stuck in the as-low-as-it-can-get mode.
Any explanation for this?

tadchem

I ‘predict’ that the melting will continue for 8 more weeks, at which time the Ice Age of 2012 will begin, and the Arctic Sea Ice area will more than double by the end of the year.

mkelly

What are the black and white striped “posts” in the picture of the melt water? Looks to be 8 or 9 of them that I can see.

We seem to have some kind of climatic lag between where we, in more southern locations, are experiencing and what is happening in the arctic and sub arctic. My experience with radar in geophysical applications (although limited) suggests the absorption comment is quite correct.

PaulH

Yes. but most of what you are seeing is rotten ice. 😉
/snark

George E. Smith;

“””””……RHS says:
July 20, 2012 at 10:18 am
Rob L,
I would suspect the satellites in use have resolution better than 10′s of meters. NOAA (not sure why) is the branch of the US government which license’s satellites and what resolution can be utilized. I think most of N. America for US companies is .5 meters and I would expect the government would allow their own satellites to go to that resolution. The US based companies (DigitalGlobe & GeoEye) supply satellite photos to GoogleEarth at pretty respectable resolution.
Google earth doesn’t usually show radar images. Image resolution is directly proportional to wavelength, and inversely proportional to antenna diameter (in wavelengths).
I doubt that radar imagery is anywhere near optical in spatial resolution (from satellites).

Ken

OK, who put the stars in the background of the Cryospehere today images?

SC-SlyWolf

Re: Arctic night
I think sunset at the North Pole is around September 21.
Temperature will drop then and freeze the “melt water.”

Will Nelson

Tom in indy says:
July 20, 2012 at 9:53 am
What’s the temperature difference between night and day? (Once “night” returns.) If meltwater freezes at night then you could compare daylight and night satellite measurements to calibrate the satellite measurements?
—————–
Having lived fairly far north back when, the terms ‘day’ and ‘night’ are a little ambiguous. Weather forecasts can go a little like, “mostly cloudy today, clear skies and sunny tonight”. 🙂

Let’s remember water reflects radar. That’s how weather radar works. My guess is ice and water are differentiated, through signal processing focused on the differences between the radar returns of water vs ice.
Ice is higher up. it’s shape is static. These sorts of things.
Just like weather radar. It’s all done with software.

Let’s remember ocean currents, not CO2 nor western decadence has caused the ice loss.
http://wattsupwiththat.com/2012/04/25/nasa-warm-ocean-currents-cause-majority-of-ice-loss-from-antarctica/

Sheesh. the problem with melt ponds is well known.
There is reason why one compares extent and area.
http://nsidc.org/arcticseaicenews/faq/#area_extent.

Any more news on the ships stuck in ice in Frobisher Bay?
I have not heard anything since last week.
http://news.ca.msn.com/local/north/resupply-ships-stuck-in-frobisher-bay-due-to-ice-conditions

“Scientists at NSIDC report extent because they are cautious about summertime values of ice concentration and area taken from satellite sensors. To the sensor, surface melt appears to be open water rather than water on top of sea ice. So, while reliable for measuring area most of the year, the microwave sensor is prone to underestimating the actual ice concentration and area when the surface is melting. To account for that potential inaccuracy, NSIDC scientists rely primarily on extent when analyzing melt-season conditions and reporting them to the public. That said, analyzing ice area is still quite valuable. Given the right circumstances, background knowledge, and scientific information on current conditions, it can provide an excellent sense of how much ice there really is “on the ground.””

Garry Stotel

Gimme another 1,000,000,000 years of polar ice satellite data observations, and then we’ll talk.
Until then – it melts, well, it melts.

kadaka (KD Knoebel)

From here:
http://www7320.nrlssc.navy.mil/hycomARC/arctic.html
Select “Movies and snapshots of the 1/12° Arctic Cap HYCOM with NIC frontal analysis overlayed”, Ice Thickness, last 30 days:
http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticict_nowcast_anim30d.gif
(Anyone got an archive link for the animations and not just the static snapshots?)
Looks like the whole mass suddenly softened up in the last few weeks, started turning, and the forecast part up to July 25 looks like it’s all getting set up to be flushed right out of the Arctic Ocean, if the “obstruction” of Greenland and those Canadian islands doesn’t provide enough resistance to hold at least some of it in.
Yep, it’ll be interesting to see how this year pans out.


You know, if they’d open up the Nares Strait to the left of Greenland, maybe shave down some of those islands around there, they could get that annoying ice out of there sooner. It’d be a real boost for shipping between New England-New Brunswick-Nova Scotia and Alaska-Western Canada.

This is a bit OT, but anyone can tell me why Greenland’s north coast is so ice-free for so far inland?
The thought it engenders is about how ice ages start – how the ice accumulates to such great thinckness over such wide areas. Cold creates desert conditions, which retards snowing and ice accumulation. As I understand it the genesis of ice ages/ice sheets is very porrly known, even if one’s common sense and the common wisdom (wrongly) tell us that cold itself can create ice sheets miles thick.
So, why isn’t that coastline covered in ice when more southerly Greenland coastline has ice much closer to the shore?
Anybody?
(I am leaving shortly and on’t be able to respond to replies, but would appreciate any feedback.)
Steve Garcia

lars

about melt ponds, see here:
http://www.seaice.de/Roesel_JGR_2012.pdf

NZ Willy

I’d say the melt is going to slow down now, as a thick rump remains. Only melting above Siberia should continue apace. The Franz Josef islands (east of Svalbard) are like a bulwark of iciness, beyond this point they shall not go.

NZ Willy

Also, at the risk of repeating myself, I think calibration is playing a big role in the day-to-day ice charts, and the calibrators are tweaking the charts to match eachother — so crowd psychology comes into play. Wiggle room is large. When the calibrators realize they have adjusted too far down they will pull it back up. I reckon this sort of interplay is much of the reason for the wiggliness of the lines on the ice chart.

Keith AB

Fascinating stuff all the same. I see Shell has opted out of drilling in the Beaufort this year.

James Abbott

Its melting. Going. Declining. Disappearing. Shrinking. Whatever word you want to use.
http://nsidc.org/arcticseaicenews/
shows that the ice edge is well behind the median line around most of the arctic basin, especially north of Russia.
There may be issues around detection of meltwater within the cap, but its largely open water beyond the edge of the cap, which on a large scale is a fairly coherent mass.
The refreeze in winter to near average could continue for many years as winter temperatures are easily low enough even with a warming arctic. Since the record melt of 2007 there have been large swings in extent between summer and winter.
Assuming the melt trend continues, because it is in open sea, the north pole may well be ice free in late summer for years while the oldest, thickest ice north of Greenland holds on.

JJ

Steven Mosher says:
Sheesh. the problem with melt ponds is well known.

And it is a problem of exactly the sort the OP politely asked about. Hardly deserving of your condescension.

Realist2

Sensors are always so difficult to keep calibrated. I wonder how much sensor calibration could affect the annual curve shape. Does anyone know of any papers on this topic?

Mariana Britez

dmi is now showing a sharp turn to the right so no we are not witnessing anything abnormal lol

mkelly said:
July 20, 2012 at 10:27 am
What are the black and white striped “posts” in the picture of the melt water? Looks to be 8 or 9 of them that I can see.
————————————–
Those are traffic markers for the myriad expected “row-to-the-pole” folks.

jaymam

Aren’t we talking about the North Pole in summer, where the sun never sinks below the horizon and therefore there is no “night”?

David A. Evans

I suspect that open water will lose far more energy through evaporation and radiation than energy gained through insolation given the angle of incidence. Another negative feedback. 🙁
I really was hoping for warmer! Warm is good, cold is BAD!
DaveE.

BA

“Also, at the risk of repeating myself, I think calibration is playing a big role in the day-to-day ice charts, and the calibrators are tweaking the charts to match eachother — so crowd psychology comes into play. Wiggle room is large. When the calibrators realize they have adjusted too far down they will pull it back up. I reckon this sort of interplay is much of the reason for the wiggliness of the lines on the ice chart.”
NZW, I’m curious about your source for this accusation. Do you suppose the “calibrators” confer before they publish each day, or is the first publisher a leader that others soon follow? Or does the proof of later readjustments lie in the wiggliness of graph lines, because the true changes would be smooth?

u.k.(us)

James Abbott says:
July 20, 2012 at 1:59 pm
“Assuming the melt trend continues, because it is in open sea, the north pole may well be ice free in late summer for years while the oldest, thickest ice north of Greenland holds on.”
===========
Care to explain the “because it is in open sea” portion of your comment, or shall winds and currents need to be invoked.

BA

“My Eyeball Mark I sensor has realized a change in the rhythm of summer-melt vs. winter-freezing in the arctic ice cover insofar as the maximum area covered during winter seems to have returned to average (pre-AGW) levels over the past 3 years,”
mogam, I’ve seen this stated many times. We all know there has been a downward trend in September ice area. Does anyone here have the statistical skills to prove there has been no statistically significant trend in January ice area, or February, or March?

mogamboguru says:
July 20, 2012 at 10:25 am
My Eyeball Mark I sensor has realized a change in the rhythm of summer-melt vs. winter-freezing in the arctic ice cover insofar as the maximum area covered during winter seems to have returned to average (pre-AGW) levels over the past 3 years, while the ice-cover during the height of the summer-melt seems to keep stuck in the as-low-as-it-can-get mode.
Any explanation for this?

Reduced clouds causing increased insolation and increased outgoing LWR.
Humidity in the Arctic has increased since around 2000. Reductions in cloud seeding aerosols/particulates would cause reduced clouds (even while humidity increases) and contribute to increased humidity, along with more evaporation from more open water.
Cause = closing of highly polluting Soviet era industries after the fall of the Soviet Union and in particular after the 1998 Russian financial crisis.

This is a bit OT, but anyone can tell me why Greenland’s north coast is so ice-free for so far inland?
Greenland is an ice filled basin mostly below sea level surrounded by mountains. Its the elevation of the ice and the mountains that causes it to be cold enough for annual ice accumulation. Even in northern Greenland, low elevations don’t have annual ice accumulation. And the further north you go the less snow falls.
In answer to you question. The north coast is ice free because of low elevation and low annual snowfall.
http://en.wikipedia.org/wiki/File:Topographic_map_of_Greenland_bedrock.jpg

Brian D

Much better concentration numbers from the Canadian Ice Service.
Beaufort and Archipelago regions
http://ice-glaces.ec.gc.ca/prods/WIS56CT/20120716180000_WIS56CT_0006545030.gif

gbaikie

“In answer to you question. The north coast is ice free because of low elevation and low annual snowfall.”
Perhaps, if the arctic gets more ice free, this region will get more snow fall. And a glacier could built over decades of time.
I don’t know how snowfall it gets now, say it’s foot or so , and it melts every year, so say got increase 5′ to 10′ of snow in fall to winter time period.