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Lord Soth

I wouldn't put to much faith in the Cryosphere today numbers. The maps are not updating but the daily anomaly is still dropping. My guess is that the computers are on autopilot pumping out garbage, and the scientists have all gone on vacation.

Im expecting a revision to those numbers.

Anu

It is a bit weird that the Arctic melt seemed to stall just as Institutions like
http://arctic.atmos.uiuc.edu/cryosphere/
froze on 7/7/2010

and University of Bremen
http://iup.physik.uni-bremen.de:8084/amsr/arctic_AMSRE_nic.png
went offline.

What is this, all Arctic researchers vacation in July and leave their computers to undergraduates ?
Maybe U. of Bremen is down because of World Cup celebrations...

Meanwhile, the heart of the Arctic Basin is breaking up (lower left):
http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r04c04.2010193.aqua.250m

Weird summer.
http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Area.png
http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Extent_L.png
Still second lowest area and extent in the satellite era, but behaving erratically.

Neven

I agree, it is intriguing how Uni Bremen has been off-line for the past few days and that CT ice concentration map being stuck on 7/7.

I don't see Arctic researchers going on a holiday during the melt season, so it's either hardware issues, or the ice is acting so weird that the sensors are speechless.

I'd go and e-mail people, but I don't want to disturb anyone.

Neven

The CT comparison maps do not seem to suffer from the same problem, so if it's a sensor thing it must be with AMSR-E and not SSM/I.

Artful Dodger

Nevi, thanks for posting the comparison maps URL. Using this tool, we can see that the melt at the Chukchi Sea is approx. 3 weeks behind 2007:

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=19&fy=2007&sm=07&sd=11&sy=2010

This is to be expected, given the late date of the 2010 Maximum Extent. However, this year's melt will be stalled until Pacific Ocean heat can make its way to the Arctic Basin.

Lord Soth

Neven

I was thinking of taking on a project to calculate the sea ice area, using the 250M resolution MODIS maps of the arctic, and using Photoshop to do the pixel counting. Here is my plan, tell me if im crazy.

1) First I will take all the 250m high resolution imagery from arctic MODIS mosaic, and stich them together in one image, if projection distortion is within acceptable limits, or I may have to do each area separately and adjust for projection distortion. Any areas with heavy cloud, I wll take the previous day or day before. This may underestimate the results a bit, but I can always correct after the fact with trending for a given area.

2) I will create a mask overlay for land areas, and code the overlay as black, so no land areas are counted as sea ice.

3) I will do some touch ups for shallow open water, algae blooms forcing them to black.

4) I should be able to digitally remove ice fog, from those areas that you can see the water/ice under.

5) I will convert to 256 grey scale and do some final contrast adjustments, to better differentiate between ice (white), sea (black). I will then let photoshop count the pixels into a histogram. I should get two distinct bell curves. With a little calculus, I will then be able to get a good estimate of the ice area using the 250 sq. meter MODIS grid. Well thats 2000 times better than NSIDC.

6) I have to add the little ice that is left in Hudson Bay, since its not part of the Arctic Mosaic.

Normally I wouldn't do something like this, but I like to get some solid numbers on why my eyes are showing the condition of the ice going one way, while the extent and area are going flat or in slow downward drift.

As a sanity check, if anybody has the figure for the total sq km of ocean bounded by the arctic circle.

Any suggestions, comments, shameless redicule ?


Jon Torrance

Neven,

Forgive a perhaps silly question from someone who doesn't look at the Cryosphere Today comparison maps much but is there a good explanation for why they are currently showing so much ice in Hudson Bay? I was under the impression that Hudson Bay had almost entirely melted, which the concentration image on the CT main page, five days out of date though it is, certainly seems to confirm.

Neven

Jon, I don't really know why that is either. You might want to read my previous blog post on this, called Inner Conflict.

Lord Soth, it sounds like a lot of work! And it also sounds like you'll need a pc with a big video card and RAM, because splicing those MODIS 250m images together is going to make an image with one helluva resolution. If you and your pc are willing and able, it would be interesting to try at least once, and if successful repeat it on a (bi-)weekly basis.

Clouds will be a problem, I guess. If you look at the current Arctic Mosaic you can see it's very cloudy at the moment. You could leave Hudson Bay out entirely to save some work. I have no idea what the figure for the total sq km of ocean bounded by the Arctic circle is. Hope this helps!

Neven

BTW Jon, when it comes to silly questions, I think I am the leading expert here.

Gas Glo

For area in arctic circle you could try globe 1 database.

http://www.ngdc.noaa.gov/mgg/topo/globe.html

The info at
http://climateprediction.net/board/viewtopic.php?f=18&t=9312
was obtained from there and indicates it shouldn't be too difficult. Resolution to 30 arc seconds sounds pretty good to me.

I believe I have read the distortion on such images is such that pixel counting shouldn't be trusted but how far out it would make it, I do not know.

Lord Soth

Hudson Bay has almost melted out.

http://ice-glaces.ec.gc.ca/prods/WIS31CT/20100713180000_WIS31CT_0005080713.gif

and

http://ice-glaces.ec.gc.ca/prods/WIS30CT/20100713180000_WIS30CT_0005080762.gif

The ice would fit in less than half of James Bay (so less than 50K sq km). James Bay is 110,000 sq km, so the bay will give you a good idea what a 100,000 sq. km of ice loss looks like.

As far as processing those images. I think I will convert the Polar Steographic to Lambert Azimuthal equal-area, so the pixel size is equal area anywhere in the graphic

All 36 images add up to close to 2Gb, so I will combine 9 images per quadrant. My graphics cards can handle it all, but the fan noise on the dual graphic cards becomes annoying when it is taxed.

I took one of the 250 meter images, imported it and turned down the brightness and cranked the contrast. The results are amazing. You get a lot more detail and perceived resolution, with just a little tweeking, and the poor conditions of the ice really stands out.

Since the sea ice extent based on MODIS, is going to take a while, it will be for historic comparison, to the NSIDC, IJIS and Cryosphere results for Mid July. After doing one of these, I will leave detailed instructions, overlays etc, to make the job easier for sombody else, if they want to crank these things out on a weekly basis.

Chartsgraphs.wordpress.com

Lord Soth

You sound like a real Photoshop guru so I hesitate to suggest ImageJ, but what the heck.

For those not familiar with it, ImageJ is a free Java based image analysis toolkit that is used widely. It is supported by NIH for medical image analysis, however applications extend far and wide. There is an active and helpful user base.

It lets you do set scale so that you can get real world coordinates as you navigate the image. It also lets you establish Regions of Interest (ROI) that you can analyze time trends over a number of images.

I've got a brief tutorial and video on how I have used it to track Nino34 temperature trends in the Pacific Link.

I've been hoping to set up a series of tutorials on how to use ImageJ to track Arctic Sea Ice conditions. I'd be very happy to work with you to make a user friendly ImageJ arctic sea ice analysis tool.


I understand if you'd rather stay with Photoshop. I'm hoping to provide a free open source tool that can handle animations and data extraction for a wide audience.

Kelly


Peter2010

There's another plausible reason that all the maps are off-line at present.

a large M type solar flare has been active over the prior week, a good reference for space weather is http://spaceweather.com/archive.php?view=1&day=13&month=07&year=2010 . I'm not too familiar with sunspots and flares,but the M class can cause substantial radio interference and effects polar regions most.

If this is the case, then maps may be off line for another while yet, Sunspot 1087 is becoming more active. maybe UV maps effected more then normal maps(Modis). Anyone familiar with the tech site of these polar satellites..

Have they been shut down into 'safe mode' to protect instruments?
Alternatively maybe Goddard is right and its a vast conspiracy to hide the mid summer increase in ice volume :D

Anu

BTW Jon, when it comes to silly questions, I think I am the leading expert here.
Posted by: Neven | July 13, 2010 at 23:09

--------------------

Here's a silly question:
If this summer melt happens to beat 2007 and set a new all time record low, how do you think WUWT would cover it in October?

I found this blast from the past by accident when searching for why "Cryosphere Today" has been down for a while:
http://www.norcalblogs.com/watts/2007/10/science_blogger_blows_gasket_a.html

The original "Watts Up With That ?" blog (started Nov 17, 2006) - dismissing the record 2007 melt with a hand wave (and using some blurry Cryosphere Today images) and a nod to Antarctica , which had lots of extra ice in 2007, so everything's fine...

Anu

There's another plausible reason that all the maps are off-line at present.
Posted by: Peter2010 | July 14, 2010 at 04:00

-----------

The University of Hamburg and the Max Planck Institute for Meteorology maintain the Centre for Marine and Atmospheric Sciences website, which is somehow managing to keep up with current sea ice concentration images:

ftp://ftp-projects.zmaw.de/seaice/NEAR_REAL_TIME/Arc_latest_large.png
http://www.zmaw.de/About-us.11.0.html?&L=1

But there is a puzzling amount of problems with other websites...

dorlomin

I wouldn't put to much faith in the Cryosphere today numbers. The maps are not updating but the daily anomaly is still dropping. My guess is that the computers are on autopilot pumping out garbage, and the scientists have all gone on vacation.

Im expecting a revision to those numbers.

Posted by: Lord Soth
= = = = = = = = = = = = = = = = = = = = = = = = = = =
Cryosphere Today measures area while the others measure extent. This may explain the difference between it and other metrics.

Gili1

Guys,

There's an interesting piece by Dr. Walt Meier, about PIPS2-vs-PIOMAS, in WATTS. Essentially it says that for ice volume estimates PIPS is not relevant, PIOMAS is. Yes,
it says so in WATTS.

-Gili

Anu

@Gili1 | July 14, 2010 at 14:16

Thanks, I don't read WUWT much anymore, but that was an interesting guest article.

WUWT sometimes pretends to be a reasonable science blog, but if you read it for a little while, the troglodyte rage shines through, e.g.:

We now know definitively that any Senator, State Representative or President that pushes cap and trade is a traitor, a liar and should be tried for sedition.
http://wattsupwiththat.com/2009/11/24/the-appearance-of-hypocrisy-at-the-nyt-note-to-andy/

Gas Glo

>"I wouldn't put to much faith in the Cryosphere today numbers. The maps are not updating but the daily anomaly is still dropping. My guess is that the computers are on autopilot pumping out garbage, and the scientists have all gone on vacation."

Have you seen the note today which says "July 14, 2010: Server issues - updating of the above hemispheric images will resume in the next few days. Timeseries plots are updating normally."?

Neven

Nice big chunk breaking off on the east side of Greenland. How big is that thing? 50 km x 100 km?

Artful Dodger

@Neven: Well, it's 300x600 pixels in the 250m res. image, so make it 75 km x 150 km... More proof that AGW is a hoax ;^)

logicman

While I was looking at an ice cap and a couple of glaciers Neven noticed a huge chunk of ice breaking off nearby, even before I posted. And then Artful dodger estimated the area. If you guys keep this up, fairly soon my predictions will look like plagiarised versions of Neven's blog! :-)

Check my latest comment in
http://www.science20.com/chatter_box/arctic_ice_july_2010_update_2

Neven

If you guys keep this up, fairly soon my predictions will look like plagiarised versions of Neven's blog! :-)

Mi blog es su blog.

logicman

Mi blog es su blog.

¿¿¿???

¿cuál es ése 'blog' ?
No hablo holandés. ;-)

Artful Dodger

@logicman: If you want to confound the locals with a foreign dialect, consider the Law of 'Conservation of Angular Momentum' in your next post on the Beaufort Gyre. Now that the Pack has come unglued, it explains all the spreading...

Anu

Not everyone is content to sit back and wait for the summer sea ice minimum.

They now sell Arctic blue lasers, so you can go up there and get that Northwest Passage open, pronto:
http://www.wickedlasers.com/lasers/Spyder_III_Pro_Arctic_Series-96-37.html

Peter2010

I'm curious, that 11k chunk off E. Greenland, when she breaks up how will that affect the 200k ice area reported on http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.5.html..

If these are 25km - 15% concentration maps reading, then that 11k ice area could turns into 30k+ for a couple of weeks.

I checked against 2009 and its all new ice cover (eg area was cleared), little multi year drifted in there when the ice reformed (http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r02c03.2009275.aqua.500m.jpg), got very cloudy so hard to tell if any multi-year pushed in there after day275.

So 2 shillings on Greenland East ice area staying at ~200k +/-15k until Aug 1st.

Anu

There was a huge mass (I'd say about 25k sq km) of ice floes in the Laptev Sea (west of the New Siberian Islands, about 75° N to 72° N) that just melted tonight - the ice concentration image showed black and blue this morning, and later today, on the same map (I didn't even realize they were updating the sea ice concentration maps during the day) half of it was just gone:

ftp://ftp-projects.zmaw.de/seaice/NEAR_REAL_TIME/Arc_latest_large.png

The East Siberian Sea, Baffin Bay and Northeast Greenland looks a lot like the pre-disappeared sea ice - dense black and blue.

Here's a good map of the Arctic if you're not familiar with the names:
http://www.geographicguide.net/pictures/arctic/arctic-map.gif

Neven

That's a great map, Anu, thanks. It's too bad the ice concentration maps from Uni Bremen and CT are down.

Kevin McKinney

Yes, I'm quite Jonesing for my CT maps. . .

Peter2010

NewFlash - the map drought has just ended..

happy to report that CT maps are now back on-line!
http://www.iup.uni-bremen.de:8084/amsr/arctic_AMSRE_nic.png

Peter2010

and from CT maps it looks like Neven will be releasing a Northwest passage is now Open for business article over the next 3 to 5 days.

Peter2010

correction, its only the uni Bremen maps back up so far, got carried away in my excitement seeing virgin map data.

Neven

Thanks, Peter, I've put the Uni Bremen map back on my Arctic sea ice graphs webpage.

Artful Dodger

The big chuck of fastice from NE Greenland has now broken nearly in half lengthwise, with the eastern portion in at least 6 fragments. Clearly, not thick or strong sea ice. There remains another 100km fringe of fastice attached to the coast which may go too.
http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r02c03.2010196.terra.250m

Neven

It's already in the animation, Artful Dodger. :-)

Artful Dodger

Udestående, Neven. Du er forbløffende.

Neven

Tak, Artfül Dødger. I have my good days and my bad days.

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