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Seke Rob

FireFox has a split view add in to see 2 - 4 images at same time or any multiple pieces of 1 web page without having to do the tab flipping. https://addons.mozilla.org/en-US/firefox/addon/fox-splitter/?src=userprofile.

-- Rob

crandles

It looks like you have done 10 dates so about 42 dates to do. Just wondering if a day and month input drop down box could be added and then use that input to generate the 8 graphs for different years so it is one page not 52 different ones. I don't have a clue and I guess Neven doesn't either but maybe someone might offer to help.

Neven

Someone has offered to help, but of course it takes time. I've also made this new segment of the Arctic Sea Ice graphs page to show how it would look like and how useful such a thing could be.

One stupid thing I did, is upload all the images as they are (0.5 MB a piece), but Google Sites only allows me 100 MB. So the next time I have some extra time, I'm going to re-upload smaller images (the resolution is quite big).

Rob Dekker

Nice concentration maps Neven !
If you need more space, I'd be happy to host the high-resolution images. Let me know..

Over the summer, I will be pointing out observations from the various buoys out there in the Arctic (as least the ones that report on-line and real-time). Now that the atmospheric temperatures approach melting over the entire Arctic itself (e.g. NP buoy reported 0 C yesterday), it may be interesting to look at this flux data from this bouy (flux data is heat flux UNDER the ice) :

http://www.oc.nps.edu/~stanton/fluxbuoy/deploy/buoy25_deltaT.html

This buoy is located in on the boundary of the Beaufort and the Chukchi. Interesting to note that even though the atmospheric temps have been well below freezing there, this buoy has been registring a 20 W/m^2 bottom heat flux, leading to bottom-melt, over the past month.

Noting that Neven's concentration map shows almost solid pack-ice there, the question is :
Where does this heat come from ?

I am open to suggestions, but one explanation is that the ice is rather thin and significant amount of sunlight makes it THOUGH the ice, causing bottom-melt while the top layer (atmospheric temp) is still below freezing... Interesting, no ?

Peter Ellis

Eh, the upward flux only started after the buoy had moved out into deeper water - i.e. it now has a huge column of liquid water under it rather than a short one. Is any further explanation required?

Peter Ellis

Um, scratch that, read the graph upside down :-)

The heat flux started after it moved over the edge of the deep basin and onto the shallow shelf. Still seems like that will be part of the answer.

Neven

Thanks for the offer, Rob. I'll see how far Google will let me go.

The concentration map pages aren't showing anything for the time being, but I'm re-uploading the smaller images later today.

I've also revamped the whole Arctic Sea Ice Graphs website. Almost done...

Neven

I think I'm done for now. Done, and done with it. Phew.

As long as 2012 hasn't reached the date in question (for instance June 1st), the daily updated SIC map is in the 2012 spot, which allows one to start comparing a couple of days in advance.

I don't know how to explain this properly, so I hope it's clear.

Rob Dekker

Neven,

Thanks for the offer, Rob. I'll see how far Google will let me go.

You know how to find me. Just let me know.

Peter Ellis,

The heat flux started after it moved over the edge of the deep basin and onto the shallow shelf. Still seems like that will be part of the answer.

That is an interesting observation, Peter. But to me, it seems that this is just an indication that deep-ocean heat flux (and reduced stratification and such) could NOT be causing this increased under-ice heat flux, so it has to be something more mondane, like the solar radiation penetrating the thin ice. Do you have any other suggestion ?

Peter Ellis

Incoming warmer, saline currents being confined nearer the surface rather than diving down under the cooler, fresher layers?

dorlomin

I have an offtopic question.

If the sea ice is at its greatest extent variance from the average in Novemberish time each year. This will mean more moisture for percipitation.

Is it possible that for a time Greenland may gain snow as the Arctic sea remains open in winter? Would this offset the additional loss from summers warmer weather?

dorlomin

And the comparisons page is amaing Neven!

R. Gates

dorlomin,

That's an good question and you're certainly thinking along the right lines. In general, warmer ocean temperatures have been shown to be associated with periods of greater winter snowfall accumulation in central Greenland, but even higher rates of summer melt, and thus the Greenland glacier loses net mass during warmer periods, even though it may see higher snowfall accumulation in winter. Here's a great chart that shows this:

http://www.ncdc.noaa.gov/paleo/pubs/alley2000/alley2000.gif

Studying this chart reveals some very counter-intuitive information. Warm climate leads to great winter snowfall accumulation, but also great summer melting, with the melting overtaking the accumulation and thus glaciers shrink.

Rob Dekker

Peter Ellis said (regarding inceased ocean heat flux in the Chukchi basin) :

Incoming warmer, saline currents being confined nearer the surface rather than diving down under the cooler, fresher layers?

Very well possible, Peter. But do you have any data to back that up ? For example, where would that 'saline' current come from, and why would it be 'warmer' ? Isn't the Pacific water that comes through the Bering less saline than the Arctic, and why would it be warmer than Arctic water, considering that the Bering had the harshest winter in (satellite) recorded history ?

I'm not saying that you are wrong. I truely don't know the answer (why heat flux increased over the past month) and honestly trying to figure out why, based on reason and available data.

Peter Ellis

But do you have any data to back that up ?
I'm a random idiot on the Intertubes what do you think? :-)

A quick Google finds me the following, which is doubtless as enlightening as it is beyond me.
http://www.ims.uaf.edu/chukchi/

The most salient part looks to be this one:

"The annual temperature cycle includes: 1) cooling to near freezing temperatures in late fall / early winter, 2) nearly constant temperatures at the freezing point from winter through late spring, and 3) warming in spring and summer due to the arrival of warmer water from the Bering Sea."

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