the Air Vent

Because the world needs another opinion

SH Sea Ice Data and Anomaly

Posted by Jeff Id on December 14, 2008

Well everyone on earth probably knows about the plight of the polar bears looking for that last ice cube to stand on in the arctic. I bet under 1/10th of the people know that the southern hemisphere has increased in ice level. We have all heard that the increase at the south pole hasn’t compensated for the NH losses, how bad is it.

sh-sea-ice-area-bootstrap-algorithm

The slope of the increase in area is 0.02910 milion Km^2/yr. The shape of the annual signal is more sinusoidal than the NH and is shown below.

sh-30-year-average-nasateam-algorithm-area

The SH area anomaly from the bootstrap algorithm by my calculation is.

sh-sea-ice-area-anomaly-bootstrap-algorithm

Now lets look at southern hemisphere sea ice extent. Slope of the red line is 0.02602 million Km^2/year.

sh-sea-ice-extent-bootstrap-algorithm

The shape of the annual extent signal

sh-30-year-average-bootstrap-algorithm-extent

And then the Ice extent anomaly.

sh-sea-ice-extent-anomaly-bootstrap-algorithm

Well there you go. The SH is adding ice at nearly the same rate the NH is loosing ice. In the NH the area is decreasing by -0.02679 million Km^2/yr while the SH is increasing by 0.02910 million Km^2/yr.

To me that is an absolutely shocking set of slope numbers, I’m learning more every day.


22 Responses to “SH Sea Ice Data and Anomaly”

  1. Gardy said

    Jeff,
    do you aticipate sharing the code for this work any time soon ?
    Also, any suggestion as to how to replicate it using Excel ?
    Thank You
    GL

  2. Jeff Id said

    It would be fairly simple to replicate in excel. I posted the code and some comments here.

    http://noconsensus.wordpress.com/2008/12/14/code-for-global-sea-ice-calcs/

  3. Jeff Id said

    In my other post http://noconsensus.wordpress.com/2008/12/13/sea-ice-area-or-anomaly/
    wordpress is having some trouble so I asked comments to continue here.

    Regarding the shift in data in 1980′s

    I would look to natural phenomena rather than mathematical, data spacing wasn’t an issue but it was a good guess. Perhaps extent is larger when there are a bunch of low density icebergs floating around or a highly fractured ice sheet but area is lower. I actually think this is what the data is.

    The top graph in the other post is of the IUIC data which I believe includes some manual corrections due to directly observed data. This graph has a continuing down slope. I trust this graph less because it requires subjectivity in creation and for it to be true there must be a “convenient” continuous upward error in the satellite observations.

  4. I bet under 1/10th of the people know that the southern hemisphere has increased in ice level.

    And even less people (particularly those who aren’t versed in climate science), read the papers that provide mechanisms on how global warming induces increased sea ice cover in the Antarctic. But if you’re paying attention, these things aren’t hard to find. I guess it helps to have a middling interest in physics, though.

    Increasing Antarctic Sea Ice under Warming Atmospheric and Oceanic Conditions

    Warmer Air May Cause Increased Antarctic Sea Ice Cover

  5. DeWitt Payne said

    Oakden Wolf Says:
    December 16, 2008 at 6:30 am,

    Hand waving and un-validated models. I’m not saying they’re wrong, but models aren’t reality, which the authors admit in the press release. So it’s only an hypothesis at the moment.

  6. Jeff Id said

    #4

    When everything becomes attributable to global warming AGW will certainly be true. I know there are explanations for everything, they aren’t all believable to me.

    I remain highly skeptical of the claim that the NH ice is global warming but the SH ice is local. There are political mechanisms in this science which cannot be disregarded by open minded people.

  7. Predictable that scientific analyses which don’t agree with skeptical preconceptions are called “hand-waving and unvalidated”. But when Spencer or Lindzen put out a model result, you don’t hear that from the skeptics. Hmmm.

    Jeff: Believability really doesn’t count. There are plenty of processes which happen in a complex system that happen counter-intuitively. Sea ice formation is not as simple as putting an ice tray into the freezer compartment and making ice cubes. Do you know what brine exclusion is? Do you know why multi-year ice has different properties than first-year ice? (Do you know why microwave sensors can detect the difference?) Do you also think that you understand these systems better than researchers who have studied them for years and can come up with probably a half-dozen other factors that influence the formation of sea ice that I can’t off the top of my head think of? Do you perhaps realize that their perception of what’s believable (and what’s true and accurate) might be somewhat different than yours?

    Plus, I didn’t state that what is described in these papers is really actually happening. I only said that mechanisms have been provided by which global warming can cause increased Antarctic ice cover. You know how in a mystery novel all the little clues have to eventually fit into one ultimate explanatory framework, even the clues that didn’t seem to make sense? Welcome to climate science!

  8. Jeff Id said

    Oakden,

    A lot of questions for sure.

    Do you know what brine exclusion is? – Yes

    Do you know why multi-year ice has different properties than first-year ice? For sure, I have read about this subject.

    “Do you know why microwave sensors can detect the difference?” — There are some notes on the NSIDC website regarding this on the difference between the bootstrap algorithm and nasateam I work in optics so the microwave descriptions make sense.

    Do you also think that you understand these systems better than researchers who have studied them for years – No.

    Do you perhaps realize that their perception of what’s believable (and what’s true and accurate) might be somewhat different than yours? – Yes, I do but feel many opinions are heavily pre-biased in support of AGW. This doesn’t invalidate their argument which may well be correct, but places a healthy skepticism on the AGW conclusions.

    “I only said that mechanisms have been provided by which global warming can cause increased Antarctic ice cover. You know how in a mystery novel all the little clues have to eventually fit into one ultimate explanatory framework, even the clues that didn’t seem to make sense?” — I have read about these mechanisms as well.

    – I don’t know your science background but in my experience physics is a harsh mistress. It’s when people claim to have the answers that the biggest eggs are laid. Your statement while true, is not unique to climate science. The fact that climatology tries so hard to claim SH ice gains are a “local” effect and NH is a AGW effect is a huge red light.

    I study very hard, understand what I read, examine relationships between data and produce results. Discussion of how the polarization of different wavelength microwaves are used in ice detection sounds pretty bad. I find that most people who aren’t into the data cannot understand CA type threads, I have trouble sometimes myself. The difference with me is that I read until I do. In the air vent I try to make the science accessible to the public. I pay a small price for that in that my blog doesn’t always sound as technical as some, leading to questions like yours here which assume a lack of knowledge.

    There are several interesting things with Mann 08 which I don’t post simply because they are too dry for reading but might be interesting to the more technical. I have a set of pretty dry autocorrelation graphs which I still might post because it is so key to the paper.

    Welcome to climate science! – It’s no different except for more politics.

  9. John F. Pittman said

    Jeff, I think I would also point that yes in a complex situation, there will be complex explanations. However, this does not mean that each step is, or should be complex. But one thing all should be is consistent. This does not mean you can’t have counter-intuitive situations, but need to apply the reasoning consistantly. One of the reasons I became skeptical is the claim that the MWP was regional in nature. The problem with such a claim is that it immediately ranks the null hypothesis as the most viable in order to keep it simple and consistant. Any other conclusion requires more proof, than arguing it does not apply (or even matter)due to data problems, it is no longer 1200 AD, etc. The differences we see where we have experts indicating that the wind may have been one of the driving forces for Antartic and Artic ice levels only underscores the difficulty claiming a single source such as AGW(CO2). Complex reactions actually may have complex reasons. It does not necessarily mean it is a single reason in a complex environment.

  10. Jeff Id said

    #9

    As an undergrad, I was analyzing an engine bore one time using holographic interferometry. The engine was a complex shaped aluminum block with a steel sleeve pressed in. We did a bunch of testing to look at what would cause a perfectly round bore to change shape.

    Holo. Fringe analysis is sometimes tricky, you take a before image make some change and take a second on the same film. Fringe lines form which correspond to wavelength size displacements with no obvious direction. I can remember filling a book with holographic images using a delta temp, looking at the images and thinking we understood the process. It was when we finally tried adding a known phase gradient (to confirm direction of motion)between the images that we learned the cylinder was moving the opposite from what we had been absolutely certain of.

    The liner moved into the cylinder bore during warming right where we knew it would go the other way. It took some time before everyone was convinced and found the mechanism but that was one of my first lessons in science. Objective review of data has unique way of keeping you humble.

    AGW is full of examples like MWP and SH ice increases being local not global. How about the articles which take other influences out of temp and conclude the rest is CO2. Like there are no other possibilities for variance. I’m so skeptical about the politics I wouldn’t call it inconsistent because it seems consistently inconsistent.

    How about Mann finding 4 different (demonstrably flawed) ways to make a HS where simple averaging cannot. What are those odds? When does he get kicked out of the club?

  11. Just checking in, and:

    The fact that climatology tries so hard to claim SH ice gains are a “local” effect and NH is a AGW effect

    Not sure why you call SH ice gains a local effect. The warming of the Southern Ocean, blamed particularly for the significant ice reductions on the Antarctic peninsula, is a consequence of global warming. There’s other things going on in the Southern Ocean related to global warming; increased wind speeds, reduced CO2 sink. I think such trends are part of the bigger mystery.

  12. Jeff Id said

    I’m not sure why anyone would call it a local effect either.

    “The warming of the Southern Ocean, blamed particularly for the significant ice reductions on the Antarctic peninsula, is a consequence of global warming.”

    I wonder how you know that the warming of this ocean is a result of global warming (man made or otherwise) or just a cyclic trend in ocean currents? I am aware of the effect, it is said to cause increased precipitation which causes the ice to grow among other things.

    If you take a moment and look at the pattern of sea-ice growth in the antarctic. It is quite clearly the result of “cold”. We know that because it is sea ice and it grows in the open water. By the graphs, the vast majority of this ice is not the result or precipitation or glacial flow. And the trend is “up” which means colder. I believe this is in direct contradiction to many predictions I have read. Some day I will play with the model data, which is becoming more available, and compare it to regional measured temps.

  13. page48 said

    Never forget Ptoemy

  14. page48 said

    Whoops – Ptolemy – sorry – I’m a lousey typist

  15. DeWitt Payne said

    Jeff,

    Something else to look at over geologic times is the formation of the cold Antarctic bottom water over the last 50 million years or so. I haven’t tried to run the numbers, but the loss of energy there combined with the formation of the Antarctic ice cap represents a negative radiation balance that continued over a very long time.

  16. cmb said

    Antarctica is losing ice, this article is a fraud. Plenty of evidence:

    http://www.google.com/search?hl=en&q=antarctic+losing+ice&btnG=Google+Search&aq=f&oq=

  17. Jeff Id said

    #16

    Ice in the antarctic has increased as nearly every study has determined. In the future the correct defense for the AGW guys is that the antarctic has been predicted to increase in the climate models with CO2 global warming.

    Warmer water increases moisture which is precipitated in higher amounts on the antarctic.

    My post is just the data.

  18. Science 24 March 2000:
    Vol. 287. no. 5461, pp. 2225 – 2229
    DOI: 10.1126/science.287.5461.2225
    Warming of the World Ocean
    Sydney Levitus, John I. Antonov, Timothy P. Boyer, Cathy Stephens

    and another

    Science 8 July 2005:
    Vol. 309. no. 5732, pp. 284 – 287
    DOI: 10.1126/science.1112418

    Penetration of Human-Induced Warming into the World’s Oceans
    Tim P. Barnett, David W. Pierce, Krishna M. AchutaRao, Peter J. Gleckler, Benjamin D. Santer, Jonathan M. Gregory, Warren M. Washington

    for starters. Sorry for the holiday delay.

  19. Well, I don’t know how to use that tag, do I? I was replying to:

    “I wonder how you know that the warming of this ocean is a result of global warming (man made or otherwise) or just a cyclic trend in ocean currents?”

  20. Layman Lurker said

    #18

    I could not access the entire paper you cited on line (Barnett et all 2005). I was able to find the abstract and a 4 page segment. It appears that the paper uses model runs to produce hypothetical “fingerprints” of ocean warming for a 40 year period starting around 1960. Alternative forcing scenarios produce the fingerprints for the alternative explanations which could possibly explain the warming. They find the GHG forcing fingerprint by the models matches the observations. Other explanations (solar, etc.) are ruled out.

    I cannot critique this and I did not attempt to search for critiques. One thing to consider is the recent leveling off (or perhaps even slight cooling) of oceans. Roger Pielke Sr. points out that there has been a divergence of model projections from observation since about 2004. He refers to this in many posts over the last several months. An example is below:

    http://climatesci.org/category/climate-change-metrics/page/3/

  21. Layman Lurker said

    Sorry I should have been a little more specific on the link.

    http://climatesci.org/2008/08/14/an-odd-weblog-by-josh-willis/

  22. Layman Lurker said

    Further to #20…

    The recent paper – Compo, G.P., and P.D. Sardeshmukh, 2008 -would appear to show through models that oceanic forcing, not GHG forcing, explains atmospheric warming trends (with data up to 2006). While the paper does not rule out natural nor anthropogenic causes of ocean warming, it does not attempt to explain causality.

    http://www.cdc.noaa.gov/people/gilbert.p.compo/CompoSardeshmukh2007a.pdf

    I am not qualified to make any assertions wrt Barnett et al, but I will throw this question / comment up for discussion: Would not the conclusion (if valid) of Compo, and Sardeshmukh, 2008 render the conclusion of Barnett et al to be circular based a priori that GHG forcings cause atmospheric warming? The “fingerprint” ocean warming due to GHG would actually be a fingerprint of atmospheric warming caused ironically by oceanic forcing.

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