« Arctic summer storm open thread 1 | Main | Polls August 2012 »


Feed You can follow this conversation by subscribing to the comment feed for this post.

Ugo Bardi

Neven, hi. A friend of mine sent me these two links. He wonders what is that blue area that you can see in the Arctic ocean (I wonder about that too). Can you explain that to us?




Hello, Ugo, and welcome to the Arctic Sea Ice blog, the only blog that is scarier than yours. ;-)
Just kidding, there is a lot of scary stuff out there nowadays, which I refer to as the Crisis Cocktail.

That blue-green colour you see, is a very, very big algal bloom off the coast of Norway. There was one last year as well, which is now my desktop wallpaper.

Unlike the recent Arctic summer storm, nothing to worry about.

Chris Reynolds

I had been about to post these in the preceding thread....

Seke Rob,

That double record is in the initial table I use for lookup functions to arrange a year/day array, but doesn't have an effect with the way I'm working. Vlookup doesn't seem phased by the double date and simply copies the correct value to the rlevant year/day cell in the 2d array.

I have however noticed that sometimes recent day numbers are wrong, and are subsequently changed. i.e. I have to manually over write the wrong days and overwrite the data when they're corrected a few days later.


These thickness plots must be from a model. They are fairly typical for what PIOMAS shows in the post 2010 spring volume loss behaviour of the ice pack. Prior to that year the edge of the Canadian Arctic Archipelago was a 'reserve' for older thicker ice,even through the summer, this has not been the case since spring 2010. The ice now thickens in the winter, but melts away in the summer.

Just checked using the link to OSTIA, the model seems to be referred to as FOAM and is a derivative of Mercator's ocean model with a sea ice component added.



Thanks for finding this, I looked for a while but didn't find these specifics.

If the web page is accurate, they migrated the model from the Louvain-le-Neuve (LIM2) model to the Los Alamos CICE sea-ice model (http://oceans11.lanl.gov/trac/CICE) in spring 2012.


One more thing, the CICE link is different than above.

See: http://oceans11.lanl.gov/trac/CICE

Chris Reynolds


Thanks for that.


The site has been updated from ice concentration maximum (03/18/12), then monthly through 070112.

August 9 has been added.

Ugo Bardi

Thanks Neven! Glad to hear that there is nothing to be worried about. You know, with all those mad bloggers around, trying to scare people.....

r w Langford

Thanks Apocalypse; The series of thickness maps shows the last remanent of the heavy multi year ice scooting around the NE tip of Greenland and melting away. Not much ice left in the Arctic, I guess Neven will have to start an Antarctic blog soon.


If I'm starting another blog it'll be about passivehouse building and gardening. :-)


These days it feels a bit like you fell asleep on Earth and woke up on Helliconia.

Artful Dodger

Nicely done, Apocalypse4Real. Do you plan to make Google Earth .kmz files available?


Alais Elena

@Apocalypse4Real, the thickness graphics are horrifying. Do you have any sense of their accuracy? They don't seem to follow the MODIS true color images that well (hope springs eternal). Thanks, Tenney


the thickness graphics are horrifying

It's my impression that the these GODIVA2 thickness maps show overall higher thickness than the PIOMAS thickness maps.

See for instance this comparison I made between images from GODIVA and PIOMAS around the same date (I turned GODIVA around for easier comparison).


My sense is that this new map may well be showing reality, more or less. My sense is that it's pretty darned difficult to assess how thick a given area of ice is. But the PIOMAS numbers are certainly treated pretty seriously.

I note that the PIOMAS chart on the bottom-left corner of Neven's Daily Graphs page is unlike most other graphs in this field-- the bottom of the Y-axis really is ZERO. And the curve right now is pointing toward ZERO and not all that far above it.

The remaining few million km-squared of sea ice is terribly thin and fragile, and not able to influence arctic climate conditions nearly as much as the old normal. I'd say that in terms of any functional significance of arctic sea ice, we are ALREADY at a functionally seasonally ice-free arctic.

Dominik Lenné

It would really be interesting how exactly they come to their thickness data.

IMO something like an "ice area mass density" - map would be interesting, too. AFAIK this is thickness * concentration * volume mass density. The latter will be very hard to obtain and could for the time beeing assumed constant.

Espen Olsen


From buoys, satellites, and from expeditions like this mail I received from about 87,5 N:

Very varying ice conditions between 1.5 - 3.0 meter, from edge of ice (south of Fram) between 0.5 - 1.0 meter.

Alan Clark

The Cryosat-2 satellite was supposed to measure the ice thickness with a high level of precision. I was expecting to see accurate thickness maps from it but I haven't seen much data from it at all. Does anyone know more about it?


Alan, most of what is publicly known, is in this blog post (especially the comments).

Espen Olsen

But by the time they have those sats calibrated and ready, there might be no volume to measure, or what do you guys think?

Timothy Chase

I found another real-time modeling analysis product that may be of interest:

Real-time 1/12° Arctic Cap HYCOM/CICE/NCODA Nowcast/Forecast System (ACNFS)

Sea surface height, ice concentration, ice thickness, speed and drift. No estimate on my part as to the accuracy, but it looks interesting nevertheless.


The thickness is off by 1 meter, Tim (the people from the Naval Research Laboratory say so themselves). It's the replacement of PIPS and is on the ASI graphs webpage, towards the bottom of the daily graphs page.

Unfortunately, I don't find the ice displacement forecast maps half as useful as the PIPS displacement maps were.

Dominik Lenné

I managed to produce an "effective thickness" map from the godiva (http://data.ncof.co.uk:8080/ncWMS/godiva2.html) thickness and area fraction maps with guess what? Photoshop. Download the maps as greyscale, open one in PS, create a multipication level and paste the second one in it. Then create a modification level and fiddle around with the gradation curves to get the color coding.
To be seen here: http://imageshack.us/photo/my-images/33/siafsithproductcolorcod.jpg/
It looks plausible but I didn't check it meticulously.

Timothy Chase

Neven wrote, "The thickness is off by 1 meter, Tim..."

Oh yes. I remember your mentioning this a while back, but I had forgotten that it was this product. A meter would seem to be significant.

Timothy Chase

Alan Clark wrote:

The Cryosat-2 satellite was supposed to measure the ice thickness with a high level of precision. I was expecting to see accurate thickness maps from it but I haven't seen much data from it at all. Does anyone know more about it?
The Guardian has an article today that is largely devoted to the CryoSat-2:
Preliminary results from the European Space Agency's CryoSat-2 probe indicate that 900 cubic kilometres of summer sea ice has disappeared from the Arctic ocean over the past year....

As to the accuracy of the measurements made by CryoSat, these have been calibrated by comparing them to measurements made on the ice surface by scientists including Laxon; by planes flying beneath the satellite's orbit; and by data supplied by underwater sonar stations that have analysed ice thickness at selected places in the Arctic. "We can now say with confidence that CryoSat's maps of ice thickness are correct to within 10cm," Laxon added.

Rate of arctic summer sea ice loss is 50% higher than predicted, New satellite images show polar ice coverage dwindling in extent and thickness
by Robin McKie Science Editor, guardian.co.uk, Saturday 11 August 2012 16.52 EDT

Peter Ellis

Great find! Definitely worth a post once Neven has time :-)

If the figures they quote are right, then PIOMAS may be understating volume - but not by much. Depends what they're calling "summer" volume, and how they got to that figure of 7000 km^3 for 2012 when we're not yet at the minimum. End-August PIOMAS model said just under 6000.


Thanks a lot, Timothy. I'll put this in a separate blog post tomorrow.


Hmmm, weird that there is nothing on the ESA website as of yet.

Timothy Chase

No problem.

The following may also be of interest:


However, it looks like the data may not be accessible at the moment:

CryoSat - PDS archive maintenance extension
10 August 2012


What the heck, blog post is up. I'm off to bed now.



Unfortunately the Google Earth .kmz files are named the same each time they run. I save them as renamed files in my Google Earth directory, but had not considered posting.

That may be something to add.




The overlay map in interesting, can you do it for the entire CAB?

Looks like I need to acquire Photoship!


Artful Dodger

Even though the data comes from CryoSat-2, the analysis is by Dr Seymour Laxon, of the Centre for Polar Observation and Modelling at University College London (UCL). I'd expect to see an announcement there, or perhaps personal communication with Dr. Laxon at the website:




Check out Gimp as a Photoshop alternative - Free & full featured.

BTW I agree with what Lodger has posted on a few threads. What we excel at is Arctic observations - not political discussions.



Thanks to all for suggestions and examples on how to overlay the concentration and thickness data. It is an intriguing.

If I did it, should it be called a concentration/thickness correlation map (CTC map)?

The August 11, 2012 data is up.

Timothy Chase

Apocalypse4Real wrote:

Thanks to all for suggestions and examples on how to overlay the concentration and thickness data. It is an intriguing.

If I did it, should it be called a concentration/thickness correlation map (CTC map)?

Actually one other thought comes to mind: use three channels, e.g., red for concentration, green for thickness, and blue for correlation, or some such.

I did something along those lines here with brightness in three different channels of the infrared spectrum for water vapor:


At a given wavelength, the brighter the image the less water vapor and the more transparent the atmosphere, implying that radiation is coming from a lower, warmer altitude.

I'm cheap, so I used Gimp.

Timothy Chase

Neven, check your email.

Artful Dodger

A4R wrote: "the Google Earth .kmz files are named the same each time they run."

It'd be great even just to be able to grab the latest daily version. It would be relatively simple to have a static link to the latest file, just upload and overwrite the previous .kmz

I'd love to see this. Right now I'd like to be able to make some shrewd guesses as to how much ice extent is still at risk for this last month of the 2012 melt season. The Google Earth "ruler|path" tool makes this pretty straight forward.

Thanks again for this excellent resource, A4R.


Dominik Lenné

This (using Photoschop to generate an "effective thickness map") was more a proof of concept. BTW paint.net does the job as well if not better.
To do this with a complete set of images or regularly would IMO require some scripting to yield reproducible results - and save worktime. This can be achieved with Freemath - I'm working on it.
Have just discovered this marvelous program and have not fully explored its possibilities. The same map, this time made with Freemath:
I am going to make the script publicly available too, when it is a bit more mature.


August 12 is up.

Artful, this is my first website, so am looking for how to post the kmz file.

Dominik, thanks for the helpful advice, downloaded Gimp, but now have to learn how to use it. I will look at the above options later today.

Off to work!

Dominik Lenné

So, any interested person may get a working freemat script for creating effective thickness maps out of thickness and concentration maps from the godiva model (
from here:


some example files are there too. HTH



Thanks for sharing your expertise in this area, it is something I do not have time to take on, but the ice effectiveness view is important to linking concentration and thickness.



The Godiva2 sea ice concentration and thickness maps have been updated through 17 August.

I am dividing the sea ice and methane concentration data into two websites. The new link for the sea ice data is:


Thanks to all who have commented on this site development.

The Arctic methane data maps site is still in development, but will be released soon.

Tor Bejnar

A4R, your thickness and concentration maps are more than awesome!

Did I get it right that the resolution (pixel?) is about 5km x 5 km? This would be on the order of a third or a quarter of a "Manhattan" (and we know what a Manhattan is because of the Petermann Ice Island that is about 2 Manhattans and we've now seen a picture of some of it). If this is right, then is the Petermann Ice Island the yellow speck in the Nares Strait on both thickness and concentration maps?


I have not checked - but would presume so.


A4R On your site [awesome] it looks like the mclure strait is set to be ice free in a few days, amongst other movements, interesting time for CA.


Hi John,

It does seem to be melting out in place. Plenty of warmth in the area.

Mould Bay is reporting 22 C today.
Cape Parry at 18 C.

James Fillion

Great post. I never knew I could learn all this great information about maps on a blog! Way to go for turning me into a blog reader. If you need any advice about AHMSI rip off, check out

Seke Rob

Fricking spam! Don't click on James Fillions links.

Bob Wallace

Thanks for your thickness posts A4R. As I watch things change I have to wonder if we will have any >4 meter thick ice left after this year. And whether there will be much 3 meter.

It seems that by doing some pixel-by-color counting one could generate individual melt graphs for different thicknesses.

It will be very interesting to see how thickness rebuilds during the freeze season. I suspect we will see massive extent/area losses in the Central Basin next year due to thin ice conditions at the beginning of the season.

The inner castle walls will begin to crumble....


Hi Bob,

We do seem to be running low on 3+ meter ice - just the Canadian fringe hanging on as more gets blown through the Fram Strait.

What the coming freeze brings is open for much conversation. We will see in March.

BTW for those pulling their own Godiva data and maps, the Godiva2 imagery seems in transition again to another server. The link I used for Sept 2, 2012 was:



Weird that there is nothing on the ESA website as of yet.


The NCOF/Godiva2 Sept 15 sea ice concentration and thickness imagery is up including kmzs.



Thanks A4R. Considering the doubts one might have about the ability for any of the monitoring equipment to show a complete and accurate picture of sea ice, it is of great use to have such user friendly sites as yours, in order for one to compare and contrast data. Looking at data from different grids, maps, animations, etc., it is clear that what little ice is out there continues to diminish and deteriorate. Seeing the visuals on your site illustrates such trends quite clearly.


Hi Brian,

The ability to compare and contrast is part of my purpose.

It seems that the decline is ending. Both the Sept 16 & 17 sea ice concentration and thickness are posted and are beginning to show increases in thickness and concentration or area in some parts of the Arctic.

I have not posted the kmzs yet.



The Godiva/NCOF maps for 18 Sept are posted and the Google Earth kmzs for 16-18 September are also added.


My plan is to post daily through 20 Sept, and then post in 10 increments through October, then monthly thereafter until sea ice maximum, unless there is a particular interest in posting more often.


Hi Arcticio,

I was attempting to get to the menu, but no luck.

The Sept 19, 2012 sea ice concentration and thickness are posted.



> attempting to get to the menu

Don't get it, images with menus?

Btw.: Do you have an idea why not thickness data end of 2011?



I was looking for how you ran the data to get your map.

Here is the link I think I was looking for:


On the thickness data at the end of 2011, I can only presume they changed data sources or created a new data set. There have been a number of ways this data has been compiled.


For those interested in an archive of Arctic sea ice concentration imagery - see the following NOAA link, which has imagery back to 1995:



The Sept 20 sea ice thickness and concentration maps and kmzs are posted.


I plan to post the Sept 25 files tomorrow.


I have added a new column to the NCOF sea ice thickness and concentration maps.

The new imagery is the MMAB Arctic ice concentration from:


I will update the NCOF data for Sept 25 and 30 when available.

Hank Roberts

Someone just asked about the Apocalypse imagery over at Realclimate in the new Unforced Variations thread. I found no contact info at the Apoc google blog page and Google led me here. If its author still reads here -- please fix the problem handling missing data.

Hank Roberts

I found the current thread with comments from the Apocalypse author, at

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.


Post a comment