Solving the problem of sea ice thickness distribution using molecular concepts

From YALE UNIVERSITY

Arctic ice, in 1957, is shown. CREDIT Norbert Untersteiner

Arctic ice, in 1957, is shown. CREDIT Norbert Untersteiner

New Haven, Conn. – Yale University scientists have answered a 40-year-old question about Arctic ice thickness by treating the ice floes of the frozen seas like colliding molecules in a fluid or gas.

Although today’s highly precise satellites do a fine job of measuring the area of sea ice, measuring the volume has always been a tricky business. The volume is reflected through the distribution of sea ice thickness — which is subject to a number of complex processes, such as growth, melting, ridging, rafting, and the formation of open water.

For decades, scientists have been guided by a 1975 theory (by Thorndike et al.) that could not be completely tested, due to the unwieldy nature of sea ice thickness distribution. The theory relied upon an intransigent term — one that could not be related to the others — to represent the mechanical redistribution of ice thickness. As a result, the complete theory could not be mathematically tested.

Enter Yale professor John Wettlaufer, inspired by the staff and students at the Geophysical Fluid Dynamics Summer Study Program at the Woods Hole Oceanographic Institution, in Massachusetts. Over the course of the summer, Wettlaufer and Yale graduate student Srikanth Toppaladoddi developed and articulated a new way of thinking about the space-time evolution of sea ice thickness.

The resulting paper appears in the Sept. 17 edition of the journal Physical Review Letters.

“The Arctic is a bellwether of the global climate, which is our focus. What we have done in our paper is to translate concepts used in the microscopic world into terms appropriate to this problem essential to climate,” said Wettlaufer, who is the A.M. Bateman Professor of Geophysics, Mathematics and Physics at Yale.

Wettlaufer and co-author Toppaladoddi recast the old theory into an equation similar to a Fokker-Planck equation, a partial differential equation used in statistical mechanics to predict the probability of finding microscopic particles in a given position under the influence of random forces. By doing this, the equation could capture the dynamic and thermodynamic forces at work within polar sea ice.

“We transformed the intransigent term into something tractable and — poof — solved it,” Wettlaufer said.

The researchers said their equation opens up the study of this aspect of climate science to a variety of methods normally used in nonequilibrium statistical mechanics.

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67 thoughts on “Solving the problem of sea ice thickness distribution using molecular concepts

  1. Well it sounds logical. But doesn’t it still suffer from the same failing as the ’70s theory?
    It doesn’t check the theory – refined as it is – against observations.

    • Step one: develop the hypothesis. DONE
      Step two: develop a testable prediction based on the hypothesis. That’s the follow up paper, or someone’s PhD thesis; hence the “opens up this aspect of climate science to a variety of methods normally used in nonequilibrium statistical mechanics.”

      • Current climate science is more like:
        Step one: develop the hypothesis. DONE
        Step two: There is no step two.

  2. The researchers said their equation opens up the study of this aspect of climate science to a variety of methods…
    …to re-jigger the past again

  3. If this hypothesis can be empirically tested and confirmed it will be valuable. If not, just more unicorn scat to fertilize academic ivy. We must have theories and theorists but we MUST use facts to make predictions, models and progress.

  4. Why is the arctic always mentioned as a bellweather and not the antarctic? Seriously, does anyone know why this is repeatedly stated?

    • Presumably because Antarctica is a continent and the Arctic is mostly ocean.This gives the advantage of blaming climate change for what the oceans do cyclically.

      • I think the Arctic > + 60 deg. lat has more land than the Antarctic, < -60 deg. lat.

        Tough call, and actually, quite hard to calculate one way or another, since the oceans and continents are not broken by latitude bands anywhere. The antarctic has 14.0 Mkm^2 of land area + 1.3 Mkm^2 of permanent shelf ice (which is not included in the world’s sea ice lists!) + 16.0 Mkm^2 of variable sea ice. At maximum, this total is greater than the combined land areas of south American + Africa that are south of the equator. The total Antarctic ice area at sea ice maximum = 14.0 + 1.3 + 16.0 = 31.3 Mkm^2 = extends out to -61.3 latitude (south latitude), much further past the “southern arctic circle” than most think. And, most definitely well past the conventional wisdom that holds everything “north of 60 north latitude” as the “Arctic”. Thus, the Antarctic sea ice alone can be shown to regularly exceed that, and “sea ice” must absolutely be considered “arctic climates” right?
        Up north? A little harder to tell, but the area north of the Arctic Circle’s 66.5 latitude is only 21.1 Mkm^2. Much, much less than the total of the Antarctic sea ice alone! And, of that 21.2 Mkm^2, 14 Mkm^2 of it is sea ice in various locations spread around in 0.110 to 2.1 Mkm^2 bits and pieces.
        So, the land area north of the arctic circle is really very, very small. But of all of the land area north of the Arctic Circle – only a little bit (such as the north “half” of Greenland) is covered by land ice all year long. The land area north of 60 north latitude is, in contrast to the total areas covered in the south hemisphere, almost completely ice-free in the summer; and almost completely ice-and-snow covered in winter. (Tree limbs excepted.) In summer, only the tiny bit of sea ice between 82 north latitude and the pole is “white” – and that sea ice has a very low albedo compared to the antarctic’s ice.
        What if you reversed the same -61.3 south latitude? Well, at +61.3 north latitude for example, you’d cut through the middle of Canada, get all of Alaska, the north half of Europe, Russia, and Siberia.

    • MarkT

      Why is the arctic always mentioned as a bellweather and not the antarctic? Seriously, does anyone know why this is repeatedly stated?

      Only the arctic sea ice is following their desired theory (greater CO2 and a lesser area of Arctic sea ice) Thus, it serves their purposes (money, propaganda, publicity, and power) to publicize only that which serves their purpose, and ignore all trends which do not support their religion.

      • @ RAcook, you made my head hurt ( with the numbers) but what has the fact that Antarctica is completely isolated by an uninterrupted ocean and air flow ( the westerlies), whereas the Arctic (above 60 degrees) has various land masses mountain ranges breaking airflow have to do with the summer/winter seasons in either? your article treats them the same it seems but they (to me any way) are two completely different beasts. The fact that the Arctic has a vastly variable climate because of terrain just makes things way more complex than the greens make it sound.

      • asybot
        September 18, 2015 at 12:10 am
        … Antarctica is completely isolated by an uninterrupted ocean and air flow ( the westerlies), whereas the Arctic (above 60 degrees) has various land masses mountain ranges breaking airflow …

        And CO2 levels increase roughly at the same pace as everywhere else, which makes Antarctica ideal to study the relationships between CO2 concentration and temperature. Think about it. The only parameter that changes is CO2 concentration, which is the one you want to study, and no other main parameter changes randomly because, as you said, Antarctica is completely isolated.
        The only problem is that while CO2 concentration has been increasing, ice extension is not decreasing, as CAGW predicts. Ice extension has been increasing, refuting CAGW.

      • The other big difference is that the earth is approximately 3 million miles closer to the sun during the northern hemisphere’s winter (perihelion is in early January), thus increasing insolation during the winter. In the southern hemisphere, insolation is decreased during the winter due to the increased distance from our sun.

    • For one thing, climate models since the first primitive versions studied by Manabe have predicted that temperatures in the arctic would warm faster than the Antarctic. The main reason for this, I believe, is the greater ocean area in the Southern Hemisphere than the Northern, as well as differences in circulation.
      There are also more complicating factors in the Antarctic, such as more significant effects from stratospheric ozone depletion.
      And then there are the differences between a pole that is mostly ocean surrounded by land and a pole that is land surrounded by ocean.

    • Because the ice extents in the Arctic had been reducing recently as opposed to growing embarrassingly large as in the Antarctic. And you can also bring cuddly polar bears into play.

  5. A chunk breaks off and lodges under another segment. There just plain old is no way this can be VonNeuman computable. No VN, no model.

  6. Oh, yet another press release about a paper that they don’t want us to actually read. !
    No title , no URL, no DOI.
    And what exactly was the 40-year-old question answered by Yale University scientists ???

  7. The only way I can think of to do a halfway decent job of characterizing the ice in 3D would be something like seismic reflection, but I cannot think of a practical way to run enough lines to grid the entire ice area in a short enough time to actually complete the task. So, we continue having an unknown unknown.

    • when galileo first measured the speed of light people didnt say it was bunkum.
      real scientists looked for ways to improve it and thanked those who worked before them.
      [Light? or did he measure the speed of sound? .mod]

      • I assume your answer is, “They confess to no such thing.”
        However a definition of “bunkum” is, “in need of improvement.”
        For example, “Galileo’s flying machine was bunkum.”

  8. I know, how about we use the fluid momentum equations ( known as the Navier Stokes Equations) to describe the Earth’s climate and solve for temperature at each grid mesh then integrate that over the planet’s surface and poof we have a global thermometer!
    What? They have? And the equations don’t compare well with reality??
    OMG!
    Dang equations!
    Anyone got a spare fudge factor they are not using?
    /sarc
    Sorry, just could not help myself after reading the article.

  9. Caleb
    September 17, 2015 at 3:43 pm
    “Or perhaps the problem with the current figures is that they show the volume is slightly increasing?”
    You’ve got it! Note that all the new science this year of the Paris Last Chance Saloon is to “deal with” all the heavy duty stuff that sceptics have raised – the biggest of course was the dreaded pause which, after about 10yrs of its stubborn flatness and 54 explanations for it, they just changed the temperatures to eradicate the pause after it surpassed the 17 years that was the limit that their CO2 formula could stand without choking. Stinky, yes, but they have been encouraged by a seemingly endless swell of useful fools into just holding their noses and doing it. Soon, as was realized by apparatchiks of the USSR long ago, it will be a given “truth” in time with repetition. The Arctic ice has begun to thicken:
    http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2.1.png
    The temperatures north of 60 have begun to drop:
    ftp://ftp.ssmi.com/msu/graphics/tlt/plots/rss_ts_channel_tlt_northern%20polar_land_and_sea_v03_3.png
    and one can see the pause and drop in temperature anomaly for the arctic. Because the trend is from 1980, it reads 3.16C/decade, but the dropping temperatures have modified this figure from 3.25C/decade a year ago. The last 10yrs of this graph show a negative trend so this figure will be accelerating downwards if it continues.
    The fix is in, though. Let me guess that the new paper finds the ice is not rethickening and the temperature is not dropping. Having found out how easy it is to just pronounce the criticisms wrong and mechanically adjust away the pause, they will take care of the thickness problem and arctic cooling, too. Long before the December meeting. The hordes of Syrians and Africans flowing into Europe will also be nicely converted to climate refugees!! Watch for it. The Himalayas will also get a new ice survey with this new “tool”.
    The pause was too devastating, causing climate science depression and once thoughtful guys like Steve Mosher have become troll like in their support for whatever comes along these days from the Clime Syndicate (term borrowed from Mark Steyn).

  10. I just wrote an equation for the outcome of our upcoming presidential election and – poof – solved it! The answer is Raymond Thurgood Lipshitz. Someone must locate Raymond and warn him to pack his bags. Unfortunately, the answer does include Raymond’s party affiliation. I’m hoping he’s not one of those commie people from the commune.

      • Recasting with an analogue. Well, that’s better than casting and hooking a log, on your fishing expedition.
        ===============

      • I’m quite intrigued. If it’s a good method it’ll likely show increasing volume, which I’ve long thought, for a different reason every time I think, is a leading indicator of Arctic Ice rebound. Time will tell even more effectively than this method, of that I’m sure.
        =============

  11. > george e. smith Wrote
    “I think the Arctic > + 60 deg. lat has more land than the Antarctic, < -60 deg. lat"
    The most used definition of the Arctic is that area north o the Arctic circle (66 deg N)
    Of its 11 million square kilometres only 20% are permanently covered in ice and snow, note that several major cities are to be found in this area including Bodo, Murmansk and Reykjavik. The best population estimates of the Arctic are that around 4 million people live there permanently
    If we turn to the Antarctic circle there we find 14 million square km of land of which 13.8 million square km are permanently ice covered. The most southerly city is Ushuaia at around 54 deg S. In the northern hemisphere there are many major cities including national capitals farther north than that. The approximate population of Antarctica is 4000 in summer and 1000 in winter all of whom are transients.
    The Antarctic is a much more forbidding place and has much more land and sea based ice than the Arctic. The climates of the two areas are radically different due to the fact that the Antarctic is a continent isolated in the southern oceans while the Arctic is an ocean surrounded by the continents of Eurasia and North America

  12. Can’t you get a reasonable approx. of total floating ice volume by measuring the volume above sea level? I would think that sats could establish sea level from summer open areas, and run representative alt profiles above that level to get exposed volume and thus total floating volume. Probably as accurate as any molecular-based theory model.

    • skorrent1

      Can’t you get a reasonable approx. of total floating ice volume by measuring the volume above sea level? I would think that sats could establish sea level from summer open areas, and run representative alt profiles above that level to get exposed volume and thus total floating volume. Probably as accurate as any molecular-based theory model.

      Problem is the extreme precision needed through all of the problems: The usual sea ice surface is flat, but with some irregular surfaces (broken up ice, ridges, etc) but then water right next to the edge of the sea ice is also “flat” and the sea surface is only 1-2 feet lower than the surface of the ice. Add in the surface water ponds on top of the sea ice. So your satellite has to detect those 1/2 foot, 1 ft, 1-1/2 foot, and 2 foot differences from the salt water surface.
      From the satellite’s “average” altitude of how many hundred thousand feet up?
      See the problem?

  13. And the heart and soul –
    “We transformed the intransigent term into something tractable and — poof — solved it,” Wettlaufer said.
    Science does not “solve” anything. you can “solve” a mathematical equation, true, but it might actually be interesting to remember that in spite of the fact that some of the aspects of the physical world can be expressed reasonably in mathematical equations, the actual world is not a math problem, nor a digital problem, nor can it be expressed accurately in a computer simulation, which in spite of it not being mentioned, I am sure this “solution” is based on. You can’t model what you don’t actually know, thus this is a nice grant gaining exercise, but brings us no closer to true understanding.

  14. There was a British Antarctic survey of the ice thickness done using a robot submarine which was reported late last year
    http://wattsupwiththat.com/
    But that did find that the Antarctic sea ice was much thicker than previously believed . In fact it showed that as a whole the Antarctic ice was at a record all time amount .
    So is it possible that using that method would not be so ” Adjustable ” in results for the Arctic , And if they got accurate figures for the amount of ice it would be shooting themselves in the foot with all of their previous claims of Arctic ice all gone by now .

  15. When ‘global warming’ alarmism first trotted out their earliest ensemble of computer models, I anticipated a population explosion of spherical cows. [https://en.wikipedia.org/wiki/Spherical_cow] I see it is still going on.

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