By Steve Goddard
CIRES photo of an Arctic ice pressure ridge
I generated an animation of 2007 sea ice thickness from the US Navy’s PIP database, and noticed something remarkable. Watch the video below, particularly inside the red square – the animation runs from May through October, 2007. The color scale on the left indicates the thickness of the ice. Watch:
At the beginning of May, ice thickness was about three metres in the center of the red square. By mid-June it was getting thicker, and by early September it was close to five metres thick! During the notorious summer of “record melt” which we have been told about ad nauseum, the ice thickness near the most affected area increased by 60%. What could have caused this? Simple – the ice was compacting to the north as it was pushed by southerly winds. It lost area – while it gained thickness.
The NSIDC news from September, 2007 touched peripherally on this idea, without actually mentioning the critical point.
The region over Siberia experienced fairly low pressure during the same time period. Winds blow clockwise around high-pressure areas and anticlockwise around low-pressure areas. The combination of high- and low-pressure areas thus fostered fairly strong winds over coastal Siberia that were partly from the south, pumping warm air into the region and also contributing to a warming Arctic. At the same time, these winds from the south acted to push ice away from the coast and into the central Arctic Ocean, further reducing ice extent in the coastal areas
Ice thickness in May 2007 was ~3 metres
Ice thickness in September, 2007 was ~5 metres
Exaggerated animation of thickness gain from compression. For effect only.
A good analogy would be shoveling the snow off your driveway. As you push the shovel forwards, the area of snow decreases – but the thickness of the snow increases in front of the shovel.
Now on to 2010. Note in the images below that ice in the Chukchi and East Siberian seas is thicker this year than it was on this date in 2007. In some locations it is as much as 5 metres thick in 2010.
May 27, 2007 Ice inside the vulnerable square (where much of the anomalous 2007 “melt” occurred) was 0.5 to 3 metres thick
May 27, 2010 Ice inside the vulnerable square is 0.5 to 5 metres thick
The AGW chameleon changes it’s colours constantly. It complains about area and extent when convenient, and about thickness when convenient. I am coming to the conclusion that the 2007 melt was more of a marketing event than a climatological event. The graph below gives a feel for just how much of a non-event it was. 2007 was 1.5 standard deviations off the 30 year extent trend, but apparently a lot of the supposedly “melted” ice just crumpled up into more survivable thick ice.
One of the ice experts must have known this. Surprising that it took the “breathtakingly ignorant” WUWT to point it out.
ADDENDUM for clarity:
Currently the NIC uses the Polar Ice Prediction System (PIPS) version 2.0 as the basis for its “operational” short-term (24–120 h) sea ice forecasts. These forecasts are evaluated daily and amended by skilled analysts using reconnaissance data (if available), the most recent weather charts and data, and historical knowledge of the conditions in the area to provide the highest quality forecasts possible out to 120 h. Special emphasis in these forecasts is placed on the location of the ice edge and the conditions in the marginal ice zone (MIZ), as these are the most critical operational areas for marine transportation and safety.
There are many factors that contributed to the anomalous September ice cover of 2007: (1) a thinner ice cover starting out the melt season than had been observed in previous years,(2) a strong summer Arctic Dipole pattern that persisted the entire summer, favoring both advection of warm air into the Arctic to promote surface melting and strong winds that pushed the ice away from the coasts of Siberia and Alaska, (3) anomalously clear skies during peak insolation and (4) warmer ocean temperatures. Several papers have been written about all these factors, and it’s not possible to say which factor was the most dominant. I would say however that thin ice played a large role since the atmospheric circulation pattern that set up in 2007 (and often referred to as the “perfect storm”) has been present in the past and yet such dramatic retreat of the ice cover didn’t happen.
Thus, the reduction ice thickness that has been observed during the ICESat era, and earlier (based on submarine sonar observations) seems to be a key driver for allowing continued low September ice extents. But scientists agree that summer weather patterns remain important. Even for this coming summer, with what looks to be the lowest ice volume during the satellite era, the atmospheric circulation remains the wild card.
I am curious why you now relied on modeled values of ice thickness and yet you discount the modeled results of ice volume from PIOMAS? What makes you trust these modeled ice thickness estimates from the Polar Ice Prediction System over the PIOMAS ones? Have you done an intercomparison of their techniques and assessed which one may be more accurate? This would be valuable information.
Re: Ice depth.
My understanding is that this is still a difficult thing to measure/estimate particularly in the Arctic precisely because of compaction. IIRC WUWT posted a nice video sequence a while ago showing Arctic ice sloshing around – perhaps someone with a better memory knows which post.
stevengoddard said at 6:30 am
I could make an estimate …… but it would be nice to have access to the original data which the maps were derived from.
Steven, just ask R. Gates or the folks @ur momisugly UW, you know the much smarter than any of us computer modelers, with their reasonable (in their opinion) match to submarine measurements “ice thickness formulas” that used the data and clearly pointed all this out in there peer-reviewed study, published in – – – – – say what?
They haven’t? They didn’t? It wasn’t? They need more money?
But….. their ice thickness chart….. What? Now they are saying ……
…
…
…
…
Hmmm, must have my sound turned down….
Okay, I’ve turned the sarcasm off, but there is only two possibilities here: 1. They didn’t know, which means at best they are –D scientists, or 2. They knew and it didn’t fit their agenda. In either case, be it a failure of comprehension or a failure of inclusion, ALL their formulas, models and conclusions are inconsequential.
Wren said at 7:12 am
The graph shows a drop in September ice extent from 6 t0 4 in 2006-2007, which is the same amount in one year that your trend line declines ( 8 to 6) over the entire 30-year period…
I have a larger version of the chart and the 30 yr drop is from 7.9 to 5.5 – 2.4, and the 06-07 drop is 5.8 to 4.3 – 1.5. Doesn’t seem the same to me but I guess everything is relevant…. I’m sorry Wren, but I don’t follow what you are saying about ice “volume” increases due to “crumpling” being reflected in the ice “extent” measurements. Specifically, the drop in ice extent…. is a measure of change which takes the crumpling into account In previous postings you (and others) have said “ice extent is not (i.e., the 2009 recovery) an indication of ice volume, which is the more important factor” or something to that effect… now your saying it is?
Anu
I do computer modeling for a living and have for most of my adult life, so I am quite fond of computer models. Thank you for your keen observation, as always.
Ian L. McQueen
There was a lot of multi-year ice pushed out into the Atlantic during the winter of 2007-2008.
That’s really interesting. That means the ice there is really thick and melting in that area will basically stop in its tracks when it gets there in August, unless other factors act to disperse it somehow.
It is impossible for the ice to melt in any year. The North Pole gets less than 2 weeks where the temperature is near 0 degrees C. as per page 38 here:
http://www.navcanada.ca/ContentDefinitionFiles/publications/lak/nunavut/3-N3637E.PDF
Most of the snow and ice that disappears does so by the process of Sublimation. Which is the transition of a substance from the solid phase to the gas phase without undergoing intermediate liquidification. This process can start at temperatures well below 0 degrees C and is the reason ice cubes disappear when left in a freezer. It is sped up with sunlight and during summer there is 24 hour sunlight.
http://www.theweatherprediction.com/habyhints2/369/
But there are definitely more than this going on.
We get these pressure ridges on our lake every winter. And even if it never gets above freezing, a strong sustained wind will open up water on one side and build a ridge on the other miles away. A lot of times when this happens, the water steams like a hot tub, when it is 30 degrees warmer than the air. It looks good enough to jump in.
pwl writes:
“As a long time snow shoveler it’s very clear that matter doesn’t just magically disappear otherwise snow shoveling would be a lot easier to do.Wow, it’s nice to find the evidence of this reduction of area without it all being a reduction in volume. I wonder how this might apply to other years?How can the ice volume be computed? How accurate would such computations be? How do we know? How were the ice depth measurements obtained? Satellite? Which? What is the “chain of custody” of that data?”
Pardon me, pwl, for writing about you rather than responding to you. But the strong interest you show in this new information about Arctic melt is the strongest evidence that can be offered to the effect that climate sceptics are seekers after knowledge while climategaters are not. As this report about sea ice thickness shows, our knowledge of the Arctic is very small and our climate science is still “a birthing.” Of course, some climategater will assert that they knew this all the time and that it was factored into the models that irrefutably prove that there is a disastrous melt of the Arctic in process. Climategaters, you are not participating in the scientific work.
I have to pause here, and give R. Gates credit: He pointed out during the April Extent bonanza that the Ice was simply spreading out over a wider area. Now it’s bunching up into a smaller area. But unisys SST temperature shows below freezing water off of Pt. Barrow Alaska where the ice has retreated.
I would expect a modicum of loss in the morphing of one extreme to the other, but not a loss figure that is implied.
Antarctic needs the same examination.
Anomaly is a two-headed monster: Cannot battle one head at a time, the other will eat you.
“I’m glad you are finally seeing the value of computer models.
They seem to be disparaged at WUWT” – Anu
It’s not really the models that people complain about, it is the claims made for them that upset people. This idea that models are inherently bad is a straw man type argument, although there are plenty of blog commenters who will spew it. Honestly presented computer climate models are certainly interesting. But to ignore there current limitations is to engage in deception.
Personally, I think this site has become too focused on monitoring Arctic Sea Ice and reacting to every seesaw. Although I’m very interested in the topic, I feel updates every 3-4 weeks normally and weekly during the minimum period would be adequate. Anyone interested in the daily/weekly status can check the link provided on the home page.
Tom P
The PIPS data is updated with a new forecast every day, and it seems pretty likely that it is verified on a regular basis. Unlike the PIOMASS which apparently hasn’t been verified against real thickness data since 2007.
http://psc.apl.washington.edu/ArcticSeaiceVolume/images/IceVolAnomaly19792010.MarNov2.png
It would be interesting to conduct a mass balance analysis to see if the assertion “Simple – the ice was compacting to the north as it was pushed by southerly winds. It lost area – while it gained thickness.” holds water. How does the mass of ice lost due to reduced areal extend compare the gain in areas that increased thickness?
The one attempt of which I am aware (http://psc.apl.washington.edu/ArcticSeaiceVolume/images/BPIOMASIceVolumeAnomalyCurrent.png) doesn’t appear to support your assertion.
Eyeballing model output doesn’t convince me of anything.
The proclamations from the taxpayer funded agencies regarding arctic ice could be used as a case study in a graduate propaganda program (MSP) The Strategic Information Plan (SIP) That appears to have been applied here is as follows:
The MISSION is to create a public demand for a transfer of authority over all decisions that relate directly or indirectly to the production and/or utilization of energy from the individual, to the collective as represented by the State.
The GOAL specifically assigned to those State scientists involved in the study of arctic ice is to establish in the population as fact, that the arctic ice cap is rapidly receding, that its disappearance is is imminent and will itself be catastrophic, and much more importantly, That the demise of the icecap is irrefutable proof that CAGW is real and an issue that must be addressed without further debate.
The STRATEGY to be employed by the institutions employing state scientists is the selective dissemination, through a politically reliable MSM, of actual measurements of arctic conditions, both in the past and in the present in such a way so as to create the impression, as described in the GOAL above
The TACTICS include, but are not limited to the following:
1. Use a period of heavy ice years as the baseline. Report actual ice conditions as relative to the baseline or to the previous year, whichever is most impactive ( I love that govspeak word).
2. When total arctic ice is in fact decreasing, either relative to the baseline, or relative to the previous year, tell the truth.
3.When arctic ice is stable in both extent and thickness report the growing preponderance of old and rotting ice.
4. When total ice is stable, but the thickness has changed report the either a decline in thickness or a decline in extent (whichever is true) . Don’t forget to mention the rotting ice.
5. When Total ice is increasing in both extent and average thickness, relative to both the baseline and the previous year, report the relative decline in old ice, and the (usual) decrease in average thickness as measured against the previous year. A comment on the vulnerability of new ice to rapid melting is useful here.
6 Always forecast ice decline for the near future. Such forecasts are a reasonable substitute for an actual loss of ice as they are certain to be reported widely in the MSM, while a failed prediction will be ignored.
7. Provide digital images, in a format appropriate for use by the media, of animals in distress, preferably mammals accompanied by their young.
ES says:
May 28, 2010 at 9:43 am
Great!. Repeat after me: “Ice doesn’t melt in the Artic or the Antarctic”
That’s for a song:
♫♫♫”It never melts in the Artic,
Though Al could tell you it does,
We know he lies
cause he’s ignorant and pedantic…♫♫♫
What a dichotomy global ice presents. Arctic ice is well below normal, and mainly on the Atlantic side, while the Antarctic is well above normal. Globally, we are pretty normal, just lopsided. Arctic being lopsided (for now), as well.
@ur momisugly geo May 28, 2010 at 5:59 am:
Perhaps the melt season actually contributes to such increase, due to the breaking up of the ice into smaller sheets and floes.
Lake Erie has been described as a “very wide river” and has a real current like a river. The current causes “shingling” of ice floes, where one floe climbs on top of another floe. This obviously makes for a greater total ice thickness when this happens. The weight of the upper floe pushes the underneath ice downward, of course. For a long time no one could figure out what was causing long furrows in the lake bottom (Lake Erie is quite shallow) until someone realized that shingling was driving the underneath ice deep enough to plow up the bottom. The furrows were due to the current carrying the floes, shingled or not, toward the lake outlet.
Reading this article, with the currents and wind as described, I thought that shingling could explain some of the greater ice thickness. After all, 3 meters (10 feet) is not exactly huge icebergs, but is rather just floes. It is also about half the depth of many places in Lake Erie.
I would suggest there is a practical limit to how thick ice floes can be and still be thin enough to shingle. Since the Lake Erie thicknesses are in the same general range as the numbers shown here, perhaps 3-6 meters is the common thickness range for such a phenomenon.
Brian D says:
May 28, 2010 at 10:14 am
For May 27, 2010, the Arctic Anomaly negative (-1.005) is completely balanced by the Antarctic Anomaly positive (1.063) as seen on Cyrosphere Today. It’s a ‘ dead heat ‘.
PSU-EMS-Alum says:
May 28, 2010 at 7:52 am
A related question: I think I remember seeing a video of wind-driven ice pack being pushed up onto the shore line (at least I think it was the shore line). It was pretty amazing to watch it happen in “real time”. Does anyone remember that video and possibly have a link to it?
—————————————–
This one?
Steve Goddard said:
“I am coming to the conclusion that the 2007 melt was more of a marketing event than a climatological event.”
______________________
Steve, that was a great series of graphic you provided– very facinating. thanks. However, a few points which should be pointed out:
Just prior to the inceasing thickness in the region on your map, we had the ice thinning and melting rapidly in July and August, as it does during the heart of the melt season. That thnner ice and currents and winds coming in from the Pacific side certainly made the mounding possible. As we discussed yesterday, it is a lot easier (i.e. it takes less forceful current and winds) to move and mound up thin ice. I would suggest had 2007 not had such thin ice to begin with, it could not have mounded up the way it did.
I also think that to suggest that 2007 was not an extraordiary year for melt and ice reduction in the Arctic, and merely a “marketing” event, is to really not understand the data. A great deal of both extent and volume was lost to reach the 2007 summer minimum, and few experts would argue with the idea that decreasing volume preconditions the ice for decreasing extent, either through melt, shearing, outflow through the Fram Strait. The Arctic Sea ice volume continues to show a very negative anomaly and declining, and that sets the stage for continued volume loss, through any number of means…
Brian D
Arctic ice extent is very close to normal. There is almost no year-over year variation at the end of May.
http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Extent.png
stevengoddard says:
May 28, 2010 at 9:58 am
Tom P
The PIPS data is updated with a new forecast every day, and it seems pretty likely that it is verified on a regular basis.
“It seems pretty likely” – demanding skeptics certainly mellow out on Fridays 🙂
Or maybe it’s the Memorial Day weekend glow…
http://www7320.nrlssc.navy.mil/pips2/index.html
On each page you will find a forecast plot for the current day. Below are sample plots. In addition, the Ice Concentration page has an archive comparing previous PIPS 2.0 forecasts with actual conditions plotted from SSM/I data.
Sounds to me like they only verify the easier “ice concentration” forecasts against “actual conditions” (satellite data), and never the ice thickness.
Of course, I’d be happy to see a citation where you prove the Navy verifies the ice thickness modeled data that you used.
I’m sure those lazy cubicle rat researchers at U of W. would like to see how those efficient Naval people do it, too.
Unlike the PIOMASS which apparently hasn’t been verified against real thickness data since 2007.
http://psc.apl.washington.edu/ArcticSeaiceVolume/images/IceVolAnomaly19792010.MarNov2.png
Since the Naval PIPS 2.0 model was developed in 1996, and ICESat was launched in 2003, I wonder exactly how the Naval Oceanographic Office (NAVO) “verified” this plot against “real thickness data”:
http://www7320.nrlssc.navy.mil/pips2/archive/retrievepic.html?filetype=Thickness&year=1998&month=9&day=4
September 4, 1998
Exactly what measurements do you think NAVO has that U of W doesn’t ?
A link would be nice.
For an examination of the effect of sea surface temperatures, clouds, etc. on the 2007 Arctic ice melt see: http://www.appinsys.com/GlobalWarming/RS_ArcticIce_2007.htm
@ur momisugly Brian D May 28, 2010 at 10:14 am:
I am not a statistics guy, but IMHO averages mean little without looking at standard deviations. Very few data sets have data points hovering around the average. With seasonal oscillations and annual variances, the real numbers hover more so around the mean value plus or minus the standard deviation, than around the average itself. (And about half those values will be to the extreme side of the (SD+/-mean) value, on the side away from the mean, which will make them look like extremes, even though they are just part of the normal fluctuations.)
Sea ice extent or global temperature averages may mean something (very little, really, IMHO, since our daily variances are often much larger than the range seen in climate anomaly graphs, and people and animals and plants survive such fluctuations with nary a shrug).
The real thing to look at is how much the “anomalies” hover around the plus or minus values indicated by the SD. I’ve not seen any SD numbers per se on global temperature data, or on sea ice, but I would guess that 90% of the years are within those. And when one or two years are outside the normal fluctuations, big freaking deal. As the warmologists say, that is only weather, not climate.
And since the Arctic and Antarctic are by definition opposites, are POLAR, their extremes should be expected to be more extreme. One would expect smaller variances in less extreme locations. Lots of ice or a dearth of ice in any particular year – holy cow!
Especially phenomena like sea ice extent, which has only been measured for a few decades, and only WELL for maybe two decades, any conclusions being drawn are premature. As to data for prior periods, proxy data is and always should be looked at with serious doubt about any particular values, and the uncertainty of proxy values must be understood to be REAL – meaning the single value that came out of the computer should be seen as a VAGUE notion.
Sea ice extent (and even volume) is something we should observe with the idea of just accumulating data. In the first several decades of the real sciences, people understood that real understanding wasn’t going to happen for a long time, but that at least they could gather data. Climatology at this time, without centuries of real, directly measured, data is still a science in its infancy – in the data accumulation stage. Just like Darwin noting down the new flora and fauna, instead of jumping to conclusions, they should just be keeping their noses to the grindstones and STFU. Darwin didn’t come to any conclusions while he was on the Beagle, and even decades later his “On The Origin Of Species” was a tentative construct.
CAGW is a tentative construct, and a fair attempt at it. But it is only an early attempt and should be understood as just a first draft. Skeptics are doing there/our kibitzing and the proponents are doing their defending of it. That is really all that is going on. That warmologists believe they have some final and solid understanding of it is totally ludicrous and immature. Critics/skeptics are just being skeptical, as they/we should be. Why the warmologists are so strident and expressing such offended-ness in their defense of a first draft makes no sense. And how a first draft could have such a wide and vociferous following is truly amazing.
Extremes are going to happen, especially with solid data sets over such a short period. Instead of being alarmed, they should be expecting to see some extremes, as the “normal” range defines itself. Sure, if we saw anomalies of 5C or 10C or half a million sq kms outside what had been seen before, we might be alarmed. But anomalies in the 0.7C range, or a few tens of thousands of sq kms? Gimme a break! Just write it down, CRU and GISS, and go STFU and quit speculating in public that it means X, Y or Z.