Arctic Ice September 2010
    By Patrick Lockerby | August 30th 2010 10:21 AM | 87 comments | Print | E-mail | Track Comments
    About Patrick

    Retired engineer, 60+ years young. Computer builder and programmer. Linguist specialising in language acquisition and computational linguistics....

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    Arctic Ice September 2010

    As I write these words - September 01 2010 - Arctic sea ice extent as reported by NSIDC and JAXA is not as low as I had expected it to be.

    image source:
    The IARC-JAXA graph shows 2010 extent as 4th lowest of recent years thus far, behind 2007, 2008 and 2009.

    image source:
    This detail, with a magenta horizontal lime added, shows the lowest extents more clearly:

    My last two forecasts of sea ice extent over-estimated the extent loss.  What went wrong?  The year started out with a delayed maximum extent - a small growth in early April - and then the extent started to decline rapidly.  Having regard to all of the feedbacks which would impact on ice melt I had expected that the 2010 extent, having dropped sharply below the 2007 figures, would continue to decline rapidly.  The erratic behavior of winds, of the Beaufort Gyre and Transpolar Drift have reduced the extent loss by a fairly large amount.  But the ice has been melting fast.

    The graph above shows how the 2010 extent drop has slowed down.  I had expected it to continue below the 2007 line, based on the observation that 2007 minimum extent still showed great amounts of ice in the Canadian Archipelago and along the east coast of Greenland.

    Sea ice extent is the measure of the total ocean area within which there is at least 15% ice cover.  Put another way it is the area within which there is no more than 85% open water.

    If we start with 100% ice cover and keep melting or exporting ice, then for as long as the ice fragments keep moving into the gaps we could well see 100% extent until the whole area contains only 15% ice.  A graph of extent against time in these conditions would be a straight horizontal line.  A naive interpretation of the graph would show no ice loss.  Even a layman's interpretation of the view from space would show dramatic ice loss.

    What has happened this year is that the ice has fragmented and thinned greatly, but so much of it has expanded to fill the gaps left by melted ice that the extent figures do not show the true state of the Arctic.  The ice has thinned and spread out, so the extent figures give no hint of the huge volume loss.

    The following comparison of six years using Cryosphere Today images shows how little old, thick ice remains this year as compared with the years from 2005 to 2009.

    images source:

    The lower volume of sea ice in 2010 should be very clear from these images.  The suggestion of lower volume in the Cryosphere Today images is supported by PIOMAS volume data:


    Ice in the North West Passage and almost all of the passages amongst the islands of the Canadian Archipelago melted away this summer, but a great amount was replaced by streams of ice from the main Arctic pack.  The ice in the main pack spread out to make up the loss.  The overall effect of this is that the loss of ice in those passages has not registered in extent figures.

    Why Arctic recovery is highly improbable

    Any news or blog report which suggests that the Arctic is recovering should be treated with great caution.  Ice extent in the Arctic - both on land and on sea - has been declining since about 1850.  The decline is obvious when old maps showing ice caps and sea ice summer minimum extent are compared with current satellite images.

    In the 1850s ships might just be able to cross Baffin Bay for a few weeks in late summer - by darting between massive floes to reach Lancaster Sound.  In some years even that was impossible.

    Until about 1900 ice extended along the east coast of Greenland down around Cape Farvel and up along a substantial part of the west coast.  As I write these words, that coast is virtually ice free.  An atlas published in 1993 and based on data accumulated from 1959 to 1983 shows how the Arctic used to melt and freeze until very recently.  The Atlas of Canada 5th edition is a valuable free resource.  The sections - such as the one used here on sea ice - can be viewed online or downloaded at very high resolution.  The images below are reduced in size for the benefit of readers who may have slow web connections or low resolution screen settings.

    Late Winter sea ice extent.

    The two dashed lines around the east coast of Greenland, outside the number 13, show the estimated maximum and minimum of sea ice extent.  The sea ice here, even in 1993 when these maps were published, could still quite properly be called the Great Ice barrier.

    Breakup of sea ice. 

    The grey area shows sea ice which the compilers of the atlas considered to be not subject to regular breakup. The main ice cover used to consist of ice which could reasonably be considered as a single mass.  Leads and polynyas would appear and disappear as the wind, blowing across thousands of kilometers of ice, built up forces which would open cracks and then close them.  Ice forced into, onto and under other ice would build up great thicknesses of old ice.  Some of that old ice would be exported through Fram Strait, but its volume was held in check by the former Great Ice Barrier and the Odden Ice Tongue.  Each year, ice exported in summer was replaced by new ice in winter, on average.

    From Nord to Svalbard the sea was formerly choked with ice.  Old ice streamed south through Fram Strait on a regular basis.  It appears to me that much of that ice melted as it traveled south along the edge of Greenland's former Great Ice Barrier, and in melting absorbed heat that would otherwise have eroded the Great Ice Barrier.  With rising air and water temperatures this sacrificial ice would not - I suggest - have been enough to protect the Great Ice Barrier. 

    Minimum sea ice extent 1939

    This map published in 1939 and compiled from data collected during the 1920s and 1930s shows the Great Ice Barrier extending down to the southern tip of Greenland.  By 1993, when the Atlas of Canada 5th edition was published, the barrier had retreated north to Scoresby Sound.

    Slowly, inexorably, the Great Ice Barrier has reduced in area until a tipping point was passed where it could no longer recover in winter from summer melt.  Greenland's east coast, much of which was formerly unreachable by sea is now accessible by sea for much of the summer season.

    As I write these words, the last landfast ice is breaking up along the northernmost part of the east coast of Greenland, as shown in this portion of the MODIS Arctic mosaic image for August 31 2010.

    Greenland August 31 2010.
    image source:

    Note that Nares Strait continues to export ice from Lincoln Sea; Kane Basin is dotted with icebergs from Humboldt Glacier; Baffin Bay is virtually ice free.

    This year we have seen significant calvings of both branches of Jakobshavn Glacier.  The calving of Petermann Ice Island, first reported here August 05 2010, produced - to the best of my knowledge -  the greatest single calving of a Greenland glacier ever recorded.  The last remnants of the Arctic's ice shelves - over 3,000 years old - continue to break up.

    The remaining older ice is confined mainly to a roughly triangular area between the pole, McClure Strait and Fram Strait.  Normal ice motion in the Beaufort Gyre and the Transpolar Drift may be expected to transport much of the remaining old ice away from that coastal area and substitute first year ice.  Ice will most likely continue to be exported through Fram Strait during the winter.


    Snow is now building on the ice, as shown by the North Pole camera.  However, as noted below, this is not necessarily good news.


    The trend towards an Arctic that is virtually ice free is inexorable.  Apart from the generally cited albedo effects there are other major factors which need to be considered.  Not only does the albedo of water substitute for the albedo of the ice which once covered the open water.  There is a substitution of thermal capacity as well.

    Formerly, the continuous sheets of ice of great thickness would radiate heat into space during winter until a great mass of ice was reduced to well below zero degrees C.  In summer, that ice could absorb great amounts of heat before getting anywhere near its melting point.  Even before that, the snows of winter would need to melt, meanwhile increasing the Arctic albedo.

    The very thin ice we are seeing now is going to be affected differently by snow.  A great thickness of snow piled onto a thin floe will overload it.  The weight of snow can submerge the floe so as to immerse the whole surface of the ice in water.  If the water is warm enough, the ice will melt and then the snow in turn will melt.  On the other hand, if little snow falls so that the ice is not immersed then that snow will melt rapidly in the Spring, as will the ice beneath it.

    Snow is a fairly good insulator.  A layer of snow on ice will reduce the rate of radiative heat loss.  If heat input from warm water is even marginally greater than heat loss to atmosphere then the ice will, I suggest, continue to melt until the water temperature drops to freezing point.

    The thinner the ice, the further the waves can penetrate.  Swell can penetrate even further.  Waves and swell tend to fragment the ice, rather than compact it.

    More open water means more opportunities for Ekman transport.  This, together with the mixing promoted by wave action could interfere with the normal currents and circulations of the previously ice-covered ocean.

    Any area of open water can freeze over in winter, adding to extent.  The ice can continue to cover open water until the coast is reached, after which the ice can pile up if there is enough time before the thaw resumes.  In fjords and channels, as the ice expands on freezing it can form ridges and thicken.  Whatever the ultimate thickness of the ice which forms in the winter of 2010 - 2011 it will be predominantly first year ice.  First year ice loses salt and gains strength with each passing year.  But, I suggest, most of the new ice which forms this coming winter will not persist into a second winter.

    But it isn't winter yet.  Until the whole area within the Arctic Circle is in constant winter darkness we shall almost certainly see further ice losses.


    Due to illness my rate of posting has dropped.  Although I try to drop by to read comments I don't quite have the energy to deal with them just yet.  But please do continue to leave comments - I value all input very highly.  You don't even have to agree with my views. :-)

    For quite frequent Arctic news, you may want to check out  -


    "my rate of posting has dropped"
    Quality over quantity, Patrick. This is another great post. For what its worth, IJIS's Area graph didn't bounce like their Extent graph. Flattened some, but then continued downwards.

    One other aspect that I haven't seen talked about much - sea surface temperatures outside the Arctic. SST's are anomalously high in Baffin Bay (hence the speedy despatch of any ice coming down Nares Strait) and in the Beaufort Sea, and that heat will take time to dissipate even after the sun drops below the horizon. But additionally, they are anomalously highthrough the whole of the North Atlantic (except for a pool of cold water dragged up by Hurricane Danielle). If I understand it right, this heat is transported to the Barents Sea and beyond by the Gulf Stream and warm SSTs should delay the freeze up on the European side some more.

    Hope you're feeling better soon.

    FrankD:  thanks for your good wishes and comment.

    The long term trend is for an ever longer melt season.  This doesn't guarantee that any particular year will have a longer than average melt season.  However, if 2010 continues the trend we may see a minimum very late in September of even early October.  In that case, my previous estimates of 3.5 to 3.8 million km2 extent may not be so wildly wrong as they appear to be at this exact moment.  :-)
    "The IARC-JAXA graph shows 2010 extent as 4th lowest of recent years thus far, behind 2007, 2008 and 2009."

    I guess that you mean 2010 extent has not yet dropped below the 2009 minimum... though it is VERY close on the IARC-JAXA graph and just below that point on on the NSIDC graph. The Cryosphere today ice AREA graph also has 2010 now below 2009 and trending towards a virtual tie with 2007 & 2008.

    You include the PIOMAS graph, but it should be noted that the 8/16 update shows that total volume was already at that point well below the previous record low (set last September) of 5,800 km^3. The way it is trending ice volume looks likely to end up near 4,000 km^3 this year. Obviously, if the volume ever hits zero the 'ice spreading' effect which has been keeping extent from plummeting further will become irrelevant, because there won't be ANY ice to spread out further. Indeed, if the volume gets much lower there won't be much ice thick enough to survive the summer melt left.

    CBDunkerson:  yes, I meant that, at the time of writing, 2010 extent was still above the 2009 figure as shown in the IARC-JAXA graph.
    The way it is trending ice volume looks likely to end up near 4,000 km^3
    this year.

    Yes, we could easily see such a low figure.  On the one hand it would be good for my reputation if the extent hit 3.8 x 10^6 km2, but on the other hand it would not be good for the planetary climate.

    edit:  'senior moment' edited out.  Hat tip to Aitch for spotting my inability to do basic math when brain-fried.  :-)
    Patrick, the Historical context you provide to all your science posts is fascinating. It really underscores that science is a process, building upon previous knowledge and evidence. As always, it is a joy to visit. Be Well!

    Artful Dodger:  thanks. 

    As Phineas T. Barnum so nearly said: "Science without history is bunk."  :-)
    Hi Patrick,

    For you all who have watched this polar web cam, lately, it is nice to see some insulation material is back in place near the north pole, and the melt pond is gone for this season:

    I willl be leaving for Nepal this friday, is there some ice to watched there?

    Regard espen

    Espen: if my reply reaches you in time, yes, there's a lot of ice to watch.

    Have a good trip!
    Hi Patrick,

    I will look into the matter, have a good rest melt season, and I hope you soon will be in a better form.

    Best Regards Espen

    Be well, your posts give a very interesting historical perspective.

    Thanks, Tony.  I've always been interested in the history of scientific discovery.  We've come a long way since the Ancient Greeks heard rumours about a land far north where the air was always filled with white feathers. :-)
    Hell Patrick, what is wrong ? I hope you get back to a healthier posting rate - and a better health - quite soon!

    Tommaso: thanks for your concern.  I have suffered from depression all my life, so I am used to living with chronic mental fatigue.  The trouble is, this time it was a physical fatigue caused by excessively high blood pressure.  For a guy who doesn't like to sit doing nothing it is very frustrating to have to ration my energy.  The pills seem to be working, but I have to be patient, have to take it easy for a while.
    With another SIE gain reported by JAXA on Sep 1st, there is a strong possibility that the melting season is over for 2010. 2010 would then be the fifth lowest SIE after 2007, 2008, 2009 and (by a whisker) 2005. I understand that annual variations do not invalidate the overall hypothesis that the arctic ice is not recovering. However, if the current minimum holds, I am a bit puzzled about the fact that the minmimum was reached so early in the season. You need to go back to 1997 to find an August minimum (29 August).

    Phil L: thanks for your comment.  Until about the middle of October we can't be sure that a minimum was reached.  Just as we had the upward blip in early April, so we could have a downward blip any time during the next 4 weeks.  From now on its all down to weather - remembering that the ice is so thin and broken that winds blowing ice into Fram Strait and Nares Strait can potentially export vast swathes of sea ice.
    You mention the icebergs coming off of Humboldt Glacier. Have you prepared any closeups of the calving front of the glacier from late this summer? This glacier deserves our attention. I will be working on an assessment this week.

    Mauri:  I would very much like to see figures for Humboldt annual calving by area.  The calving front has not retreated in the spectacular fashion of Petermann or Jakobshavn, but it has retreated significantly since about 2000.  The glacier is so wide that a loss of 100km2 barely shows in the MODIS images.

    This year we have seen a long sea ice melt season.  Kane Basin sea ice seems to me to substantially slow or even prevent calving, but once the sea ice is gone, the calving rate seems to be quite high.

    This is the most recent reasonably clear image from MODIS Arctic mosaic:

    image source two subsections at 250m resolution from:

    Calving seems to be more rapid in an arc to the south of the tongue, arrowed in the image below.  This is clear from comparisons of images from earlier years.

    The slow retreat of the front suggests that mass balance is almost being maintained.  If the sea ice in Kane Basin melts earlier and / or freezes later, this may be expected to extend the calving season.  In such a case I would expect a significant annual retreat - something of the order of 200 to 300 km2 per annum.




    all images 2003 - 2006 are end of August, sourced from:

    In case you missed this:

    I'll try to follow up any more comments / suggestions / queries you may have.
    Patrick, fascinating history of the Arctic ice. Seeing all the information all in one place makes it very clear that the amount of sea ice left is tiny compared to 1933. Hope you keep feeling better. You are doing very important work.

    Hello Patrick,

    Sorry to hear you're not well.  Joke on its way by email.
    Robert H. Olley / Quondam Physics Department / University of Reading / England
    I enjoyed your article on Arctic sea ice and how it behaves. However, I believe you missed one great effect of the loss of summer Arctic sea ice. You mentioned the loss of albedo effect, and that is a very significant effect. You did not mention the effect of the loss of Arctic ice on the weather of northern Greenland. I believe much of the weather of Northern Greenland comes across the Arctic Basin to the northwest. This perrenially frozen tract of ice has the effect of chilling the air, and enveloping Greenland in a perpetual deep freeze. When the Arctic basin ice is gone for the summer, then the air coming to northern Greenland will be above freezing. This should have an accelerating effect on the melting of Greenland ice. What do you think?

    Craig, I agree. Not only will the air not be chilled, the whole region will very likely be warmer due to the heat content of the water. If I am remembering correctly, the region will warm 4 to 8 degrees C. due to decrease in albedo alone. Even more warming will occur due to changes in circulation patterns before things get really complicated by changes in air circulation, the Gulf Stream and other factors. Sorry no links. Maybe somebody has links to these documents handy.

    Craig: I agree also.  We are already seeing a warming trend.  If you take a number of factors into consideration the prospects are bleak.  The loss of albedo will raise sea temperatures.  The rise in temperatures will affect Greenland and the sub-Arctic.  Loss of sea ice, ice caps and permafrost will reduce the thermal capacity of the Arctic generally.  The midsummer heat input to the Arctic is greater than for the tropics due to the 24 hour sunshine.

    Altogether, sea ice albedo and thermal capacity loss will predictably lead to land ice albedo and thermal capacity losses.  What we don't yet know is how fast this will happen.

    Further reading:
    Colorado Bob
    It's not just Greenland -

    Houston weathers its hottest recorded month

    August average of 87.8 degrees beat highs set in 1980 and 1962
    Colorado Bob
    This record was set due to hotter more humid nights.
    Okayama and dozens more Japanese cities also recorded their hottest month. The average temperature for our city was 30.5C (87.1F, at a latitude of 37-40 or so). We were punished by both 35C (95F) highs and 27C (80.5F) lows. The number of days of both was unprecedented. Average temperatures for August were about 4degrees C (high and low) above the running 30-year average (already higher than pre-1970's averages). The first week of September shows no relief. By this time of year, unlike Houston (if I remember my youth correctly), our daily low temperature is supposed to be 21C (68F) low to 28C (83F) high.

    As a concerned citizen, I have followed The Cryosphere Today and the North Pole Cam almost daily over the last five or six years. Intuitively I have been able to piece together the continuum in terms of sea ice loss in the Arctic, but until now have not been able to clarify many questions concerning a real understanding of ponding, old ice, and historical ice extent data. Thank you so much for a great read--it is appreciated. It's all a bit sad at a human level when thinking of the consequences of ice loss, but, on the other hand, reassuring to know that accurate information is being presented.

    "The following comparison of six years using Cryosphere Today images shows how little old, thick ice remains this year as compared with the years from 2005 to 2009."

    Nothing about thickness or ice age in these images.

    Try this:
    Ice age at the end of 2009´s melt season, at the end of july 2010 and the same but with a black line showing the actual extent (aprox). I expect more multiyear ice at the end of the melt season in 2010 than in 2009. And in 2009 it was larger than in 2008. Taking this in account, I think a record volume low is not expected.

    But the pattern during winter will be very important. With low AO conditions as in 2009-2010, the export of old ice through Fram strait will be small. If the Tranpolar Drift works on... you know.

    Of course the sea ice is not what you thought it would be. You are not a scientist. You do not understand what facts are. It has never even been suggested by DATA that the earth was warming, or that man's actions were warming it.
    I think America needs to begin teaching science in universities, so we all don't appear to be imbesiles.

    I think America needs to begin teaching science in universities, so we all don't appear to be imbesiles.


    Colorado Bob
    It has never even been suggested by DATA that the earth was warming, or that man's actions were warming it.

    "I think America needs to begin teaching science in universities, so we all don't appear to be imbesiles."

    So, why are you adding to the appearance?

    So, Capuchin, if you look at the historical maps of Canada that Patrick provided links to in this article it appears that the minimum extent of Arctic ice in the 1930s is not too different from the maximum extent in 2010 except for the southern reaches of Arctic ice which historically have melted every year anyway. It doesn't take a professional scientist to see this, only someone with eyesight and a vision center in the brain that can correctly process what he/she sees.
    When I look at the current MODIS satellite images of the Arctic my eyesight and brain vision center have difficulty seeing very much beyond what the more knowledgeable people post so I think I am going to believe much of what they say. I see and read little from credible people of what you say.
    Oh, by the way, when a person spells words correctly it gives more credibility to what that person has to say. I looked up "imbesiles" or should I say tried to look it up in "The American Heritage dic-tion-ar-y of the English Language--Third Edition" and was unable to find it there. Maybe you meant "imbeciles" since that is the word closest to your spelling of "imbesiles." Maybe you are trying to invent a new word. I think there is a process for submitting new words to the companies that publish dictionaries. Maybe you could look into that so we can understand what you are attempting to say.

    Ok then. You have refused to set a limit to your argument. You have limited your argument I guess, to a time when areal photographs were in use. This is about 100 years. In geologic terms, an insignificant time fram. Not even a dot on a graph. I must repeat, get smart. Get some intelligence and attend a university where professors do not telerate ignorance. Data is data. Climate and geology will always change. That is a given. If it rains today, I do not make the conclusion that we are in the midst of a permanant rain that will kill all humans.
    Grow up people. Get some smarts. Learn what politics is and what science is.

    Firstly: Since what you you are saying seems to be a personal attack on me, let me say, "What you think of me is none of my business."
    Secondly: I have in fact two degrees from two different universities but I am not going to give you the satisfaction of knowing where they are from or what they are in.
    Thirdly: "fram" is not in my dictionary but I did a Google search and the closest I got was this from
    Fram ("Forward") is a ship that was used in expeditions in the Arctic and Antarctic regions by the Norwegian explorers Fridtjof Nansen, Otto Sverdrup, Oscar Wisting, and Roald Amundsen between 1893 and 1912. Fram was probably the strongest wooden ship ever built. It was designed by the Norwegian shipwright Colin Archer for Fridtjof Nansen's 1893 Arctic expedition in which Fram was supposed to freeze into the Arctic ice sheet and float with it over the North Pole.
    Fram is said to be the wooden ship to have sailed farthest north and farthest south. Fram is currently preserved in whole at the Fram Museum in Oslo, Norway.
    Is this what you meant?
    Fifthly: The Arctic ice is melting abnormally; the earth is warming abnormally; we caused it; soon the bill for us doing all this comes due. Don't worry; you won't be left out; you will pay your fair share.
    Sixthly: I won't be wasting any more space on this blog responding to you.

    Fram is a Norwegian polar ship that is now in a museum in Oslo, Norway. I visited it again during the IPY Oslo Science Conference this June.

    Fram front view

    And here is the proud polar farer Nansen in front of his ship (not only his....)

    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth
    Thanks Bente, those are really cool photos!!

    Colorado Bob
    I have argued with these folks for years now. And I have observed they break down into general groupings.
    "Cap" falls under the heading of "Dense Gobbly Gook " , all though  "Cap" is a rather poor example of it. The hallmark of this writing is a confused tangle of verbage, that in the writer's mind seems " smart and well thought out ".  Like the kid in middle school who didn't read the lesson, but get's called on for an answer.
      Say when the  Inquisition was pounding all those square pegs into round holes, for example.

    There is a scientific term for this paragraph , it's called " bullshit".

    does get points however, he just didn't type ....... " NO, NO, NO ".
    Thanks Colorado,
    Very well said.
    BTW, I've spent a little time in Nevada, climbed Wheeler Peak, been to the Petrified Forest, etc. My Great Grandfather rode "shotgun" on the Wells Fargo Stage through that territory around 1865.

    "You have limited your argument I guess ..."

    No, no, no!  That's not it! Not it at all, d'you see?  Scientists aren't allowed to guess.  They have to search for facts.  Sorry, I mean FACTS.  You must have missed the bit where I mentioned that Arctic sea ice has been declining since 1850.

    Then again, the Arctic has never been fully surveyed using aircraft.  Not enough aircraft, pilots, fuel, logistics support, money etc.

    Before the age of satellites, the Arctic was mapped just like any other place - by triangulation.  That method dates back to the Ancient Egyptians who - I am reliably informed - didn't use aircraft.

    I think America needs to begin teaching science in universities, so we all don't appear to be imbesiles.
    Who is this 'we'?  Climate change deniers, perhaps?

    As for what is taught in America - it is not relevant.  I am British.
    Learn what politics is and what science is.

    But I did learn that.  As a small child in the 1950s.  I had a very smart father who taught me to smell the stench of propaganda a mile away.  You, Capuchin, are a propagandist and as such you are not welcome to make comments here.  If you want to contribute to the furtherance of scientific knowledge, fine.  But if your intent is to repeat the mantras and doctrines of your anti-science puppet-master - sorry, organ grinder - then I repeat, you are not welcome here.

    Capuchin with organ grinder.

    The most annoying thing about the organ grinder was that he would keep repeating the same old tune over and over.

    Regarding your comment in which you said "I expect more multiyear ice at the end of the melt season in 2010 than in 2009. And in 2009 it was larger than in 2008. Taking this in account, I think a record volume low is not expected. "

    Why not? To the best of our knowledge, the current record low volume was set in September of 2009, despite there being more area covered by multiyear ice than in 2008. Maybe, just maybe, it matters how thick the multiyear ice is, not just how much area it covers.

    Assuming you accept that, regarding your "Nothing about thickness or ice age in these images. ", there was nothing about thickness in the image you then offered either. Multiyear ice tends to be thicker than newer ice; it isn't thick by definition. Consider, a piece of multiyear ice continues to be multiyear ice as it loses thickness through melting right up until the thickness reaches zero. Only then does it cease to be multiyear ice - when it becomes liquid water.

    Colorado Bob

    Turning Up the Temperature in the High Arctic

    "There is clear evidence of climate change here," Werner said via email from Svalbard. "The Linne´ Glacier has been retreating since 1936 at an average rate of 20 meters per year. Since 2002, that rate has increased twofold, to nearly 40 meters per year. Now, we're seeing the return of warm-water-loving mollusks. These results are consistent with other Arctic regions that likewise show accelerated warming in the past two decades."
    Colorado Bob,
    Looks like we owe Patrick an appology, we both put up links to this blog and the riff raff has followed us.

    You provide an insight that is not available elsewhwere, We thought it was worth sharing.

    Tony, Colorado Bob, Patrick,
    I am guilty as well(putting a link) so I owe Patrick an apology too. I also think it is more than worth sharing.

    Colorado Bob
    Tony -
    Maybe so, but I get the feeling Patrick can stand the em'.  Me, I just make fun of them .
    Colorado Bob

    September 3, 2010

    It is obvious that the conditions met by the early explorers such
    as Vitus Bering, Fridtjof Nansen, Adolf Erik Nordenskiöld and Roald
    Amundsen no longer exists.
    We passed through in a few weeks, while
    our predecessors were forced to overwinter once or even twice. Still,
    it is not an easy passage for any kind of boat or vessel. There is
    still ice, although not to the extent there used to be, but plenty to
    make conditions unpredictable for ships. In addition many of the seas
    you have to pass are very shallow. In the East Siberian Sea, the
    shipping lane is located 50 nautical miles off the coast, in order for
    there to be sufficient depth for bigger ships. Lights, buoys and
    nautical markings are scarce.
    I have posted a discussion on Humboldt Glacier , I will look forward to further image contributions that can be utilized on this front, and addressing questions that I have not considered or thought I had answered.

    Colorado Bob
    Colorado Bob

    Giant Greenland Iceberg -- Largest in the Northern Hemisphere -- Enters Nares Strait
    Colorado Bob
    ESA's Envisat satellite has been tracking the progression of the giant iceberg that calved from Greenland's Petermann glacier on 4 August 2010. This animation shows that the iceberg, the largest in the northern hemisphere, is now entering Nares Strait – a stretch of water that connects the Lincoln Sea and Arctic Ocean with Baffin Bay.
    Colorado Bob
    Colorado Bob
    I have learned  more about our icey world here in the last month than I ever thought possible in this late date in my life.
    Colorado Bob
    The Humboldt Sink -
    In north central Nevada , the Humboldt River struggles into a vast desert were in disappears into what was once a giant salty marsh.  South of it lays , the 40 Mile Desert, at the end of that was a place called " Rag Town "  on the Carson River, flowing to it's own sink in the same vast desert.  This was how you got to California in 1850.  I have been all over this country looking for geothermal energy, 30 years ago.
    Craig Dillon
    According to Cryosphere Today, the Arctic is losing about 50,000 sq km of ice per day! It is only about 200,000 sq km from matching the record low of 2007. So, by this Saturday, if it keeps up, then 2010 will set a new record. Of course, one reason this is happening is that much of remaining ice cover is very thin, so it doesn't take much to melt a large area. On another item that bugs me -- the NSIDC measures ice coverage as any area with more than 15% ice...that is bullshit, in my opinion. Now, 15% may be a good measure if you are determining what ocean areas would be safe for maritime traffic. But, for saying the ocean is covered or ice-free, that is ridiculous. Ice free should mean mostly or substantially free of ice, not necessarily completely. I would put the threshold at 30%, give or take. Now, Cryosphere Today shows a lower number for ice covered area than NSIDC. I could not find what their rules for classifying ocean as ice-free or ice-covered. Does anyone know?
    I am assuming that they take the % ice cover for the area that they are measuring and use that figure. For example, if they measure 100km^2 and determine that it is say 60% covered with ice they would report 60km^2 of ice coverage not 100km^2. I do not know what resolution their measurements are based on so there is still that margin of error though. Maybe there is someone who can confirm this.

    Craig, the NSIDC ice EXTENT is the area of OCEAN with at least 15% sea ice. My understanding is that percentage is used because it is the limit of what could be reliably picked up by the resolution of the earlier satellites.

    The figures shown on the Cryosphere today site are ice AREA... effectively the ice EXTENT multiplied by the average percentage of ice concentration. If the ice extent were at 100% concentration it would equal the ice area. This is why the two figures approach each other during the Winter freeze up and then diverge more and more as the Summer melt takes place.

    BTW, the IARC-JAXA graph DOES use a 30% concentration limit for ice extent. However, this gives results only a little different than NSIDC because once the ice gets that scattered (70%+ open water around it) it tends to melt quickly. Also, the IARC-JAXA ice extent graph has now dropped below the 2009 minimum like the NSIDC ice extent and Cryosphere today ice area.

    Time for another Lockerby Ice Island animation:

    The rest of us should be so lucky as to get a runaway glacial train as a namesake!
    Luck has nothing to do with it. You could have spotted it too, Hank. It's not like Patrick has his own private satellite in orbit. Or do you, Patrick?

    Me, I was feeding my daughter's hamsters at the time and didn't hear the alarm bells going off. ;-)

    But I'm sure there must be a Campbell Strait or Channel somewhere on the Canadian side of the Arctic.
    Not exactly in the Arctic, but there you go, Hank.
    200 years is a long time to wait for new recognition, but the fact that it was a seal hunting base is pretty cool.
    Hank: just for you - an Arctic convoy escort destroyer - HMS Campbell.

    After the massive losses of convoy PQ17, when 24 out of 35 merchant ships were sunk, more ships were allocated to the defense of Arctic convoy PQ 18, amongst which was HMS Campbell.  She was attached to the convoy from Loch Ewe to Iceland, August 2nd to August 7th 1942.

    In the 1940s Arctic sea ice extent was at a high level.  The convoys to Russia sailed through ice-filled waters with unsurvivable temperatures.  Arctic convoy duty was probably the most terrible duty for any man or ship in WW2.

    I don't know if HMS Campbell sank any enemies, but it's a safe bet that she shook a mighty fist.
    There you go, Hank. A sub-Antarctic island with a seal hunting base and an Arctic convoy escort destroyer. Now stop whining. ;-)
    Aw, come on, Hank

    It's not everyone has Highlander in his blood either...Doesn't Clan Campbell trace back to [King] Robert the Bruce?

    Just how invincible do you need to be?

    Before that even, King Arthur if you can believe in that guy.   Scottish history, and Norman before that, is rife with Campbell stuff.  Heck, the only funny part in Braveheart was a Campbell.  See the end of this clip:

    But that's all ancient history. Sure, this 'science 2.0' stuff has name recognition in a small segment of science, but my ancestors apparently invented dick jokes. That's something to brag about.
    Ha Ha

    Just spotted the follow on post.....

    "Nothing about thickness..."  ......hope dick jokes aren't following you around?

    "Nothing about thickness..."

    NSIDC: "Figure 5. These images compare ice age, a proxy for ice thickness,..."

    Is the ice age a proxy for thickness? Yes
    Are the extent or concentration (or PIOMAS) proxies for thickness? No.

    In my knowledge, the record volume low was in 2008, not 2009. (NSIDC minimum press releases)

    Regards. :-)

    Is the ice age a proxy for thickness? Yes

    Not necessarily. It depends on the compaction.
    It would seem that we are now entering a stage where even the data processing paradigms must be called into question. Nevin has put up a very interesting post on the North Hole. The dates they shift from summer to winter code, still valid? The ice is changing so fast that one wonders if the well calibrated methodologies are still well calibrated.

    I don't mean it as a criticism and I am very glad it is not my problem to sort out. Seeing a problem is very different from having the slightest clue how to solve it (I do not).

    Hanks comment on King Arthur, is it worth a post on how fact and myth get intertwined? For my two cents worth Arthur was very real, but not like the 14th century picture of him. It looks like there was even a rather massive round table.

    Okay, it just requires belief that one source, Geoffrey of Monmouth, was correct 600 years later while historians of the day who never heard of Arthur were not.

     But, yes, I was referring to the French romantic notion of him (and the knights, etc.) which couldn't possibly be true.   A band of Celtic leaders, etc., and even a round table are plausible, you just have to define round table as to be neither round nor a table, and every generation had new leaders so that part is easy.   It's certainly fun to think about.
    Norma Loire Goodrich wrote what I would consider the definitive work on King Arthur - and she goes into it willing to accept anything and map linguistics and fact to suit the narrative so it is quite enjoyable if you can suspend disbelief of the obvious things.   Her efforts for the Holy Grail and Merlin were less successful though.
    Arthur was a Celt and eventually the Celt's lost. Winners write history. The round table probably was not right across but more a circular long table so that the warriors could be served from the inside. Best guess; Camelot was on Cadbury Hill built of wood.

    The name Arthur was much more popular in the time after the period of King Arthur. The author Bede could prove interesting. After the Saxons won it is almost as though it was forbidden to talk about King Arthur, because many of his battles ( Victories) are accepted history. It was not until after the Saxons were defeated by the Normans that discussions of Arthur were acceptable.

    Coming in a bit late but re: "I expect more multiyear ice at the end of the melt season in 2010 than in 2009. And in 2009 it was larger than in 2008. Taking this in account, I think a record volume low is not expected. "

    Expected or not, its what we got.

    Comparing PIOMAS current volume with average volume we are sitting at a little over 4000 km^3. Yet on their site they say: "September Ice Volume was lowest in 2009 at 5,800 km^3 or 67% below its 1979 maximum. "
    So we are currently 30% below last years record low volume and still falling.

    PIOMAS estimates the volume, without real data of thickness.
    Believing PIOMAS is a question of faith.

    I think the record volume low was at the end of the 2008 melt season, and NSIDC thinks so:
    2008: Arctic Sea Ice Down to Second-Lowest Extent; Likely Record-Low Volume
    2009: Arctic sea ice extent remains low; 2009 sees third-lowest mark

    Walt Meier,s opinion about PIOMAS estimates of record anomaly of volume in spring 2010:
    "But what about the PIOMAS volume anomaly estimates? How can they be showing a record low volume anomaly when there is less of the thinner first-year ice than in previous years as seen in ice age data? Doesn’t this mean that PIOMAS results are way off? Well, first, it is quite possible that the model may currently be underestimating ice thickness. No model is perfect. However, there is a possible explanation for the low volume and the PIOMAS model may largely be correct.
    The areas that in recent years have been first-year ice that are now covered by 2nd and 3rd year ice will increase the volume – in those regions. However, compared to the last two years, there is even less of the oldest ice (see images below – I also included 1985 as an example of 1980s ice conditions for comparison). The loss of the oldest, thickest ice may more than offset the gain in volume from the 2nd and 3rd year ice. Also, it’s been a relatively warm winter in the Arctic, so first-year ice is likely a bit thinner than in recent years. Finally, the extent has been less than the last two years for the past couple of months. So the PIOMAS estimate that we are at record low volume anomaly is not implausible."

    OK Walt, but making numbers following NSIDC,s minimum press release (, we have:

    end 2008-winter 2009:
    (4.7 million sq. km at the end of the melt season)
    Third year ice, or older: 27% of 4.7 = 1.269.000 km2
    Second -third year ice: 8% of 4.7 = 376.000 km2
    First year ice: 65% of 4.7 = 3.055.000 km2

    end 2009-winter 2010:
    (5.35 million sq. km at the end of the melt season)
    Third year ice, or older: 19% of 5.35m = 1.016.500 km2
    Second --third year ice: 32% of 5.35 = 1.712.000 km2 de hielo de segundo año o más.
    First year ice: 49% of 5.35m = 2.621.500 km2 de hielo de primer-segundo año.

    A little less oldest ice (250.000 km2) , but 1.350.000 km2 of second-third year ice more in 2009 than in 2008.

    In this image from Tschudi 2010 we can see the typical thickness for each ice age, according to ICESAT measurements:

    And here we have the ice age at the end of april in 2009 and 2010 ( with PIOMAS saying the record volume low was in 2010.

    With these maps, the amounts of ice of each age and its typical thickness, I think PIOMAS is obviously wrong.

    I haven´t faith.

    A question: what is the source of the map of 1939?

    So you think PIOMAS is wrong and you do not have faith in it.

    Some sources would agree that it may be understating the volume loss, although I gather you believe it overstates the loss.

    The chart you cite above from the presentation in 2010 by Tschudi indicated that for ice of a given age, the ice in 2008 was equal or thinner to similar aged ice in 2007. There is no data after this date due to the failure of the satellite, but if this thinning of older ice continued after 2008 then there could be volume declines even if the area of ice over the age of 2 years did not diminish.

    Using the data you provided above, ice older that 2 years declined by 250K. Isn't it possible that this ice declined not only in area but that ice of a similar age declined in thickness compared to 2008?

    Based on the chart you cited, there does not appear to be a significant difference between the thickness of first year ice v. second year ice. Second year ice is not twice as thick as first year ice. Based on the chart it looks like first year ice is 1.7 meters and second year ice is 2.0 meters for a difference of about .3 meters, while ice older than 4 years can be between 3 meters and almost 5 meters thick.

    Do you have a source for an alternative estimate of ice volume from a different model?

    Are your numbers above based on ice extent or ice area? The extent numbers include areas with as much as 85% sea water. I think I saw a source that said the use of the "at least 15% ice cover" standard was related to the sensitivity of the satellite.

    Will the data from CRYOSAT-2 be able to provide an actual measurement of ice thickness to test the validity of the current estimates of volume provided by the PIOMAS model?

    CRYOSAT-2 is currently undergoing validation and calibration

    Have you checked out the PIOMAS v. ICESAT model validation chart? The chart from Tschudi 2010 presentation that you cite above is based on the same satellite that was used to test the PIOMAS model.

    The summary from Tschudi 2010 states:

    "The ice pack is, on average, much younger in recent years. We have related age to thickness, which shows that younger ice is also thinner."

    What is your assessment of the ice volume chart in the Tschudi 2010 presentation that was next to the chart you cite above?

    Anonymous: sorry I missed your question:

    A question: what is the source of the map of 1939?

    Modern arctic Exploration by Gunnar Seidenfaden, 1939.
    Trans. Naomi Walford.  Pub. Johnathan Cape 1939.

    Apart from his many other visits to the Arctic, Gunnar Seidenfaden was the manager of Lauge Koch’s 1931-1934 East Greenland Expedition.
    Thank you very much Patrick!

    The ice volume chart in the Tschudi 2010 presentation ends in the 2009 winter-spring. The volume was slightly lower than in 2008 (11.900 km3, Maslowski 2010 - ): OK, I agree, it´s possible. .
    In that chart, Tschudi uses the age as proxy of thickness, and he estimates the winter 2009 volume using the ice age combined with the median thickness measured by ICESAT in 2004-2008. The less oldest ice explains the lower volume in 2009, despite the increase of total multiyear ice. (Interesting: real measurements of thickness in april 2009: Lange 2010 As in 2004-2007, thicker than in 2008 )

    But at the end of the melt season in 2009, the amount of multiyear ice was bigger than at september 2008). Thinner? We (or PIOMAS, or Barber) can especulate: but we don´t know!

    Lower volume in april 2010 than in april 2009 as PIOMAS says? I see the map of ice age in the two years ( and the typical thickness (, and I think that using the estimate of Tschudi for winter 2010, the volume would be larger than in winter 2009. I´m waiting the update for 2010.

    CRYOSAT-2 will be very useful.
    (following, PIOMAS is not checked with real data since 2007)
    Thank you for your answers. Sorry for my english.

    September 15th, 2010 arcticle on volume reduction of arctic ice with charts and graphs and supporting data and references:

    Said in the link you provide:
    "Given that the ice is almost certainly thinner now than in 2008, we are very likely to have witnessed a lower total ice volume." ?? ... Why is it thinner??

    I suppose they think it is thinner because: "This figure would support thinning of the icepack over the last couple of decades since older ice tends to be thicker than younger ice. You can see in this figure how little of the really old, and thick ice there is left in the Arctic Basin." Younger ice, thinner ice. OK, I agree.

    Ice age at the end of the 2008 melt season compared with the ice age at the end of july 2010 (with a red line showing the actual extent, and with little red arrows showing the ice drift during last month) :

    I don ´t know, maybe we have a record low volume this summer, but in my opinion it is not so clear. I see more multiyear ice now than in 2008. In my understanding, the record low volume at the end of the melt season was observed in 2008. The volume at the end of the melt season in 2009 was bigger (a lot more multiyear ice), and now in 2010 it would be unclear, or bigger too.

    The volume in winter:
    Graph provided in your link:
    Ron Kwok updated that graph (Maslowski 2010), saying the volume in winter 2009 was a little lower than in 2008: new record low despite the little increase in the overall area of multiyear sea ice: OK.

    And what about winter 2010? I see the map of ice age at the end of the winter in 2009 and 2010 ( and the typical thickness measured by ICESAT (, and I think the volume would be larger in winter 2010 than in winter 2009. The amount of 2 and 3 years old ice is a lot larger than in 2009.

    Sorry, broken link.
    This is the right one comparing ice age at the end of winter 2009 and 2010:

    September 15th PIOMAS is available:

    still nothing from CRYOSAT-2 to test PIOMAS model against.

    While I respect your efforts, I am not sure whether using ice extent, ice area, and ice age maps and images to get a fine tuned current number is necessary.

    I would be more concerned with comparisons of 2010 to 2000 and all years before that rather than splitting hairs (I am losing mine) about whether a new record was set in 2010. The ice is acting and looking like it is thin, and there is no doubt it is below the volume for all years before 2000 based on satellite images. There is no indication that ice volume will return to levels that existed before 2001.

    In 10 years we may not need a sophisticated satellite to determine the arctic sea ice volume at the September minimum.

    Once volume goes below 1,000 km^3 what difference will it make what the volume was in 2010?

    Maslowski,,s reference is in page 12: "Lowest Winter (Feb-Mar) Arctic sea ice volume in 2009: 11900 km3!!!(R. Kwok, NASA/JPL, Personal communication)

    looking at the ice extent it seems that if it were not for the old ice jutting out in the the East Siberian Sea it would be almost identical to 2007, However what may really matter is volume of ice which is worrying,

    It matters little if PIOMAS understates or overstates Arctic ice volume as long as they are consistent. Even if PIOMAS overstated ice volume by 10%, which I do not believe they do, the trend line for ice volume would be similar except slightly steeper. Understating would make the line slightly less steep, but it still hits "0" at exactly the same place and time.
    There are at least two points that are important:
    1. The trend on all the ice measurements, extent, area, volume, are all decidedly on a downward trend, with ice volume being on a decidedly steeper and steeper trend downwards. If we watch ice melting on a lake we see extend and area decrease very slowly at first and continue to drop slowly until a "critical point" is reached, then suddenly drop to "0" as the ice disappears. Volume on the other hand follows a much more linear trend which steepens to some degree as ice volume approaches "0".
    2. If we want to compare absolute volume, extent, or area it is important to look at each model individually and compare data in that model to other data in only that model. Doing so makes small biases in each model irrelevant. By comparing trends of all models with the trend of each of all models we get a much better idea of the overall condition of the ice trend than with any one model.
    People who think Arctic Ice is recovering forget to do this.

    At one point my state was under water and now it is not. That is a very extreme change and it was not caused by man. If we contribute to it ,the only solution would be to kill off the human race, thin out the human race by population control whether openly/covertly or de-industrialize the world. If we do that we would have to give up the technology we are using to study climate change. Also research into developing new technology would cease.

    Our nature to advance would have to cease if you really want to solve the global warming problem. All this talk about carbon tax and eco police are very stupid things. Taxing people would not solve the problem as the earth cannot go to the mother earth doctor and pay her visit with our taxes.

    I will indulge that we do add to the problem but it is not bad enough to say that the sky is falling. The earth has seen many changes without us to think that this is such an anomaly.

    Even having said that it is hard to believe that we have such power to destroy a planet so passively. The sun is also heating up, is that caused by us too? Other planets are experiencing drastic climate changes. Is that caused by us driving SUV's? If the sun and the planets remained the same and only the earth would change I would drink the koolaide and join the fight to save the planet. The sun has a major roll in this. If the sun were blocked out we would see the earth cooling but when the sun heats up we are not smart enough to think it will heat up. Get real.