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idunno

Hi Neven,

I think I remember seeing something like this last year in the Canadian Archipelago???

I think its a sign of very thin ice.

Neven

You might be right about the CAA, idunno. I vaguely remember seeing it with the fast ice there.

But I wonder, if it's very thin, why hasn't it started breaking up yet? Especially with that big low moving over it in he last couple of days.

Looking at last year's animation the ice doesn't turn blue before breaking up. Or could this be due to the difference in brightness?

Twemoran

Other areas experiencing the same coloration include the bight near Pevek, at the other end of the ESS and some areas bordering Amundsen Gulf.

Modis shows similar coloration in 2009 & 2010 around day 170.

Some of the affected area near Tiksi is not sea ice, but possibly frozen muskeg.

Is it possible we're seeing methane producing bacteria or methane devouring bacteria through thin ice without snow cover?

Great Slave Lake is also showing a very unnatural color as the ice breaks up.

Terry

Account Deleted

Neven, +21 measured only the airport.

At the official weather station (which began observations in 1948), the maximum temperature was +19.4C

Therefore, the excess of the record only three degrees.

Neven

Thank you, Arcticicelost80. I've edited the sentence.

Otto Lehikoinen

My guess would be slush on top of the harder more solid ice. But that is a large area for that.

FrankD

idunno, a very large part of the CAA was blue last year around day 170 - fast ice and sea ice alike it lasted for a couple of weeks and then around day 185 it started to diminish until by around 190 the ice cover was mostly white again.

It's not obviously (or at least not consistently) associated with large scale break ups, so I doubt that it is thin ice (although that was my assumption when I first saw it).

Its possible that its surface melt, and in this case, refroze around day 185. Obviously that would require a cold snap - does anyone have weather data for that period for the CAA to validate / refute that idea?

crandles

>"My guess would be slush on top of the harder more solid ice. But that is a large area for that."

What about the sharp outline of dark rocks?? with light blue channels (sand?) running through them? How does that fit in with slush on top of solid ice?

I also believe we tend to see it in similar locations to greater or lesser extent each year. Why the similar locations rather than widely/randomly distributed?

Shallow depth of water may well be involved? (Did I read 6ft maximum depth in this area by a sail around the arctic team? Perhaps much shallower in this corner?)

>"But I wonder, if it's very thin, why hasn't it started breaking up yet? Especially with that big low moving over it in he last couple of days."

With clear outlines, does this mean no rafting/ridging? Perhaps the water freezes all the way to sea bed which presumably would prevent rafting/ridging leaving fairly smooth surface. It would also mean strong winds won't break it up.

Espen Olsen

I reminds me of ice melting at certain stage, it is often seen in Norway in the spring when frozen ice on rocks from a source is starting to melt and being refrozen over and over again?

Peter Ellis

Crandles: I wondered if it might be bottom-fast ice, but a quick Google found at least one paper saying that bottom-fast ice only extends a few km from the shoreline. Depth there is of the order of 20m or so.

The "blue" may be something to do with freshwater ice melt as compared to saline ice melting - it does seem to happen mainly in river deltas where there will be high freshwater input, plus the channels of the Canadian archipelago that receive a lot of freshwater from glacial runoff and snowmelt.

Neven

That's a good one, Peter!

Chris Reynolds

Only tangentially related, but the colour of ice reminds me of this.
http://www.meltfactor.org/blog/?p=453
Greenland Ice Sheet Getting Darker by Jason Box PHd.

I don't know why the ice is blue, but think Peter's proposal may be on the ball. Although Frank's idea of surface melt may be the better idea - depending on where the ice in the CAA was blue. Freshwater influx during the melt season wouldn't affect the surface colour f ice in the way melt and e-freeze would.

Neven, am I correct in assuming the image of the blue ice is at 400m resolution?

Seke Rob

Algae bloom, but zoomed in, the fringe shading makes it look as if above the ice of thin cloud... part of a mask used? Who's got contact with the image processors will be able to get it from the source.

-- Rob

Neven

Neven, am I correct in assuming the image of the blue ice is at 400m resolution?

It's a cropped image of the 'regular' 1 km image.

Aaron Lewis

Bare ice, with or without a film of melt water over it.

Most ice has surface crystals (frost or snow) that provide the white. Even if there is some melting, most ice gets cold at night and new layers of frost crystals form, leaving the ice white in the morning. If the surface is above freezing, the crystals melt showing the blue of the ice below. Ice from compressed snow has air inclusions that appear white through its volume, & etc.

See for example melting ice from the GIS : http://ocean.dmi.dk/arctic/image_container.php

Llosmith57

I remember a National Geographic article from 1969 about the retrofitted oil tanker Manhattan trying to break through some deep blue ice in McClure Strait. The article and caption both referred to the MY ice as "diamond hard keel busting blue". This ice was bare and very thick. I would concur that this ice is without cover and a remnant of MY ice that is now a pale image of its former thickness.

Llosmith57

Sorry, I meant to add that, the current ice is without cover and a remnant of MY ice now thinned by melting and a pale image of its former thickness.

michael sweet

All this blue ice is first year ice. It looks to me like ponds on top of the ice. Last year when it was cold for a few days the satellite image would look like solid ice again.

Neven

That also sounds very plausible, Aaron Lewis!

k eotw

Dunno if this helps, the image isn't identical but then it isn't spring

"The bottom image is a close-up view of the area immediately south of the polynya. In this image, the sea ice appears blue and more loosely packed than the ice farther north. The bluish color of the ice is the result of liquid water from melting on the surface of the sea ice."
http://earthobservatory.nasa.gov/IOTD/view.php?id=6963


Tor Bejnar

I understand that glacial ice is blue because there are virtually no air bubbles. No, I’m not suggesting this is a glacier we’re looking at!

When Spring flooding precedes sea ice breakup, at least some freshwater will flood on top of existing ice and then freeze (incorporating any snow that was on the ice.) Might this show as blue ice? How far out will a fresh water flood flow on top of fast ice? Enough to create all this blue? Plus some much smaller patches on the CAA coast.

Our fire department used to flood the natural ice skating pond [natural ice, man-made pond], but they used hoses to spread the water. But it sure took care of thin snow cover and white scraped ice! The next morning, the ice always looked clear (except for air bubbles and old tension cracks).

The “brown” ice may be clear, showing the shallow sea bottom, maybe. The brown ice has the same white crack(?) patterns as does the blue ice.

Steve Bloom

I would think that those Tiksi temps require extensive surface melt in the adjacent area, whether or not that's the reason for the blue.

Kris

Tor B. wrote:

I understand that glacial ice is blue because there are virtually no air bubbles.

Absolutely correct.

And the ice becomes like that after having been for thousends and thousends of years under high pressure, a pressure which squeezes the air out of the ice.
That is blue ice. Which is very, very old ice.

But mind, under certain circumstances, or better under a certain angle of sunlight (rays) the ice emits a blue shine. Due to light refraction. The result of same phenomenum you see when looking at a rainbow. The result of same phenomenum you see from tegula of Butterflies, scales of certain reptiles, feathers of certain birds.
And that ice IS NOT blue ice!

Bottom line, let's keep the head cool. :-)

Mike Constable

When looking at http://www.arctic.io/observations/ last year (and appearing this year too) there was a definite blue tinge in the western border of the Greenland ice sheet, and the melt pools within were deep blue.
I do not know if the colour could be an artifact of the rendering of the data, but clean pure water (and ice) does appear surprisingly blue anyway.

FrankD

Kris that's a really interesting idea, but I'm not sure its what we are seeing here.

Looking at the CAA for one day last year: http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r04c02.2011175.terra

I note two things:

1. There is a very clear demarcation between the ice in the CAA (blue) and the mobile ice in the Arctic Basin (white) (towards the right-hand side of the image).

2. The bottom left corner of the image is a different swath to the main image (as seen cloud changes on left and bottom edges). In the centre, there is no cloud and the two swaths join seamlessly.

If the effect was related to the angle of the sun or the satellite pass, I would have thought it very unlikley that two separate images at different angles at different times of day would look so similar, and nor would different areas of the one image look as different as they do.

So I doubt its an image artifact, but I certainly wouldn't rule it out.

Arcticio

The video from last year's melting season shows the surface changes the color twice:

http://www.youtube.com/watch?v=8AX-Hq_MLRY

As the Arctic warms up in Spring, first the snow cover is getting wet and turns the color observed from satellites into a grey-ish white. Later on melting ponds appear and the color becomes blue-ish.

Apparently the color change happens within a few days and may qualify it as a metric of the length of the melting season.

Lord Soth


Whether the ice is white or maybe blue,
it's nothing for you, to lose your cool,
please don't tell me I got it wrong,
for in a month, you will find it; long gone.


And this is why I don't make a living as a poet. :)

idunno

oh you got blue ice,
oh you got grey ice,
oh you got green ice...

Shortfatape

I looked up blue ice a couple of days ago after the original comment, and Kris summed it up: "pure" ice with no tiny air bubbles is blue, and ice with air bubbles is white.

My theory is that it's related to the high air temps: there's probably a constant sheet of water on top that's flowing down through every crack and crevice in the ice, displacing any air in all those little fissures. As the meltwater flows through those cracks into the sea underneath, it's replaced by new meltwater on top, so the cracks never "dry out". There's still a lot of air trapped in the ice, hence the light blue color.

The beautiful, sapphire-blue of glacial ice is because much more of its air has been pushed out by pressure.

Werther

Blue ice: hey…it’s melting! It happened last year too, in my opinion it’s a thin layer of water on top of rather smooth lake- and fast ice. It probably takes its colour through refraction of light. It’s glass-like properties reveal all cracks and structure. Especially in the Laptev a lot of sediment and organic matter is incorporated in the ice. Further, the Lena and other rivers are dumping a lot of it under and over the fast ice. It’s melting fast and losing strength, up to a point (10 days) where it can crack and melt out completely.
About the punctuation fields I noticed in February: could still make some out 40 km north of Cape Bhuor Kaya, right in a zone where the ice is stained brown. I’m quite sure now these are circular holes in the ice. They have mostly remained open through winter. They probably vent methane from decaying organic matter in molten shelf bottom permafrost. These are not methane clathrates.

idunno

There are several blue glaciers visible on the DMI maps of Greenland, on the Qaanaq link.

Is it possible that the blue colour indicates nothing more than a complete absence of snow-cover?

Neven

Seke Rob wrote:

Algae bloom, but zoomed in

Rob, I had to think of your comment when reading this today:

Scientists have made a biological discovery in Arctic Ocean waters as dramatic and unexpected as finding a rainforest in the middle of a desert. A NASA-sponsored expedition punched through three-foot thick sea ice to find waters richer in microscopic marine plants, essential to all sea life, than any other ocean region on Earth.

That said I still think the explanations of melted snow/water on top of fast ice that doesn't refreeze, make the most sense.

Neven

The ice is still blue and some of it is breaking off. Not that this means anything.

Werther

Hi Neven, it means we’ll have that fast ice starting to break up within 5 days. Last year around day 170. Snow cover is gone; last year it was still over Kotelnyi and Lyakhowsky island.
Blue is also around in the CAA straits, in the Beaufort, coasts of ESAS, Kara and Baffin Island. It is also sunny in a lot of regions. NOAA/NCEP SST is showing the area colder than -1.5 dC is shrinking.
Looks like the numbers will come in soon enough. And mind… it’s volume that matters. ECMWF shows a reverse in LTP next ten days. That could mean compaction time in the Kara-Laptev region.

Werther

For further interesting reading on the actual state in the Laptev Sea:
http://idw-online.de/pages/en/news482023
Laptewsee: Messungen zeigen dünnes Meereis
Ralf Röchert Communications Department
Alfred-Wegener-Institut für Polar- und Meeresforschung

06/08/2012 09:41

Werther

Laptev
This is the pic with the AWI/IDW article;red is thicker than 50 cm

Neven

Thanks for that, Werther. AWI press release is here. I might do a post on this later today.

Neven

That fast, blue ice between the Lena delta and the New Siberian Islands is starting to break up big time. About 10 days earlier than last year.

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