RC’s Dr. Eric Steig boreholes himself on Antarctica

This is something that needs wider circulation, hence its appearance here. I’ve been mulling over how to best present this, and decided there’s nothing I could do in the way of excerpts that still told the story effectively, so I decided to present it in full. I’m pretty sure Jeff won’t mind. Readers may recall Steig et al 2009 and its cover picture on Nature saying the whole of Antarctica is warming, and the skeptic response paper O’Donnel et al 2010 response demonstrating conclusively that the peninsula is warming, but the whole of the continent is not. The reason for this is the same flawed PCA flawed statistical methodology, similar to what was used by Mann to create the Hockey Stick.  Jeff Condon, co-author of O’Donnell et al 2010  tells the story at his Air Vent blog.  Andrew Montford also has a post on it where he opines about the Steig et al 2009 paper possibly being included in IPCC AR5. – Anthony

Proof and Genius

Posted by Jeff Condon

I know you guys missed me, Real Climate sure did. Eric Steig has written a letter to “The Guardian” (booming voice) in response to a Nic Lewis letter patiently explaining problems in an article written by yet-another-know-nothing with a keyboard.  Unfortunately for us, the article itself has been updated in response so we can’t read the original.  What is interesting about the exchange is Dr. Steig’s wild reply.

My bold. 

Nicholas Lewis (Letters, 28 August) complained that your report (Arctic ice melt likely to break record, 24 August) gave the impression that typical temperatures in Antarctica have risen as much as on the Antarctic peninsula.
While he is correct about this, his letter also refers to an outdated study of his, which argued that previous estimates of overall Antarctic warming were too high. In fact, the work of Lewis and co-authors has been proven wrong.

The relevant paper here is Orsi et al, Geophysical Research Letters, vol. 39, 2012, which shows that the rate of warming in west Antarctica is as great, or greater, than what we showed in our original work (Steig et al, Nature, vol. 457, 2009). Moreover, Lewis’s own paper shows there has been
significant warming in west Antarctica and that the average trend over Antarctica is of warming, not cooling as is often stated.

The reality is that the Antarctic is warming up and is contributing significantly to sea level rise; and that there is strong potential for a greater contribution to sea level rise from Antarctica in the future.

Professor Eric Steig
University of Washington, Seattle, USA

Our 2010  study is now outdated???
Seriously!!  This absolutely is the doctor who never learned about matlab.
For those who have not read the history of the Antarctic wars, here is a pictorial summary.

Steig said this on the cover of Nature magazine:

We said, no you screwed up the math so using the same data it is more like this:  (Ryan O’Donnel)

Because without the satellites the temperature stations alone say this:

So it absolutely cannot be the image on the right:

Steig 09 smeared the peninsula warming across the continent (see how it is missing from the peninsula on the left), but now he says O10 has been “proven” wrong.  This tells me that he has apparently never understood that  the result we produced is nothing more than thermometer data.   That is all it is.

Temperatures as reported by thermometers.  It is a skeptic plot I tell you!!

Perilously, Steig 09 was precociously printed on the previously prestigious primary page of Nature publication.  Carelessly comprised of contaminated and crappy satellite data with thermometers taking a tertiary role in tolling temperature.   Sorrily, Steig’s seminal segment was further stuffed by sloppy math.  (alitteral too far?)

So Jeff , what did he base his conclusion that the PCA distributed thermometers of O10 are now “outdated” and “proven wrong” on?

A single borehole temperature reconstruction at a single point……

One spot

—->     o     <—-

Genius!!

It was workmanship like that which got me labeled as a skeptic in the first place.

Notes to Real Climate and Orsi:

The PCA method S09 attempted to employ, is about redistribution of thermometer information according to covariance of AVHRR satellite data.   By nature, every temperature station affects every point in the reconstruction.  Kriging the temp stations, is a far more controlled and far more verifiable solution for the same thing and it would produce the same result as O10.   The 3 pc’s of the Steig 09 method “smeared” the thermometer data everywhere, so no matter what is published, S09 methods will NEVER be verified.   S09 can never, and will never, be correct….because it isn’t!  The fact that it is to be cited in AR5 is yet another wart on the last few grains of credibility the IPCC holds.

Sorry for that.

Does the error of S09 that mean that O10 is right?    No, of course not.  But O10 is very close to actual thermometer results.  This is because in a “skeptic” plot, we cleverly used actual thermometers.  Bunch of morons I say.  This is in direct contrast to S09 which preferred 3 pc’s of highly noisy Satellite AVHRR data WHEREVER available.  That was not a smart plan ….. Um, if you want good results.

Even with enough pc’s as O10 used, there are points in this sort of reconstruction with noisy data, where modes of the PC are a dominant factor in creating the local trends of the plot.  These methods mean that station information can be and IS copied across an entire continent.  This was proven by the S09 cover of nature(Figure 1 above). The trick is to minimize the information bleeding. What this means to me is that I am quite comfortable that the O10 reconstruction will never be proven wrong, not because something as massive and complex as o10 doesn’t contain a boo-boo, but rather because it is an approximation of a field.  The best anyone will ever do — is improve on it.

Apparently, this is something that Steig has never figured out.  He might not ever work it out, but science is a cold sport and my guess is that those who are smarter than him  ….. will.

===

Other notes of surprise:

What normal thinking person would take a temperature from a lousy borehole and hold that out as superior to an actual thermometer?

???????

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78 Responses to RC’s Dr. Eric Steig boreholes himself on Antarctica

  1. Luther Wu says:

    The sad fact is, Steig and all the other pseudo- scientist shills are the only voices that most people ever hear. Modern truth, as fed to the masses, has reached the pinnacle of Goebbel’s dream.

  2. adolfogiurfa says:

    A peninsula stick! (if mirrored horizontally).

  3. Les Johnson says:

    I hope that Steig checked with Mann, first, because the Orsi paper says that the LIA was a global event.

    oops.

    From the paper:

    This result is consistent with the idea that the LIA was a global event, probably caused by a change in solar and volcanic forcing…

  4. Nylo says:

    Priceless. They definitely need a new way to communicate science to the public lol! Better to shut up than to come with crap like this, they hurt their own “cause” more than skeptics do!

  5. Les Johnson says:

    And figure 3 in the abstract would also indicate a MWP.

  6. Alex says:

    Amen. Why is it that such simple and obvious realities and deceptions are allowed to hang out there as “credible” in a science community? I have watched this for 17 years in plant science (biotechnology and bogus claims of organic farming superiority) and marveled/nauseated at the gall and success of the deceivers.
    I’m now convinced that the “journal” model of scientific discourse is/has always been terribly flawed and inadequate (too easy to rig publication and responses) and that the science community should embrace an electronic forum system where vigorous debate and hypothesis testing/proposing can occur real-time and PUBLICLY.
    Thanks for being a bit of that and here’s to more of honest, frank, dissection of truth and reality.

  7. Pointman says:

    When their basic reasoning faculties, never mind their science, are just that bad, what else can you do but have a laugh at it. Amusing piece Jeff.

    Pointman

  8. vukcevic says:

    Antarctic ice cover rising, solar magnetic activity falling, any connection?
    Some 6 months ago I discovered that the Antarctic’s magnetic field decadal change and the sunspot magnetic activity (from which the TSI is derived), show good correlation
    http://www.vukcevic.talktalk.net/TMC.htm
    but in percentage terms change is far greater in the case of the earth’s magnetic field (as if there is kind of geomagnetic amplification involved)..
    Dr. S. tells me that it must be a coincidence, but I am not entirely happy about that.
    Still trying to understand what mechanism can be responsible and what consequences for the Antarctic and S. Hemisphere temperature might be.

  9. Urederra says:

    huh?No mention about the misplaced Harry station? I though It was the main cause of warming.

    http://climateaudit.org/2009/02/02/when-harry-met-gill/

  10. Steve Keohane says:

    What normal thinking person would take a temperature from a lousy borehole and hold that out as superior to an actual thermometer?
    A PNS ‘scientist’? oh, wait, you specified ‘normal…

  11. KR says:

    “…the same flawed PCA math used by Mann…” – Not really, neither the latest Mann work nor Steig 09 use PCA.

    Steig 09 (ftp://soest.hawaii.edu/coastal/Climate%20Articles/Steig_2009%20antarctic%20warming.pdf) uses a regularized expectation maximization (RegEM) method. What it shares with PCA is that it is an iterative refinement method, a gradient descent fitting method, honing in on an answer by reducing error terms at each iteration. But it doesn’t share the math of PCA.

    Iterative methods are a well known and characterized method of solving problems that do not have a direct analytic solution. Examples include simulated annealing for the Traveling Salesman problem, Richardson-Lucy deconvolution of astronomic images, and any number of industrial optimization problems. These methods have demonstrated success over and over again.

    Regularized EM in particular (http://en.wikipedia.org/wiki/Expectation-maximization_algorithm) attempts to find the best fit of unobserved values given known values (such as in this case coastal temperatures and satellite IR records), given correlation of temperature anomalies and error bars on measurements. In EM you iterate between a set of estimates of your unknowns (which can be random at the start, although I prefer beginning either with uniform values such as “1.0″, or just interpolation of known measures), estimate forward what would be observed, and calculate errors between that and actual observations. You then use those errors to update the estimates of the unknowns. Repeat both steps until the errors converge to somewhere near zero (an asymptotic process, but well below known measurement errors is a good threshold).

    It’s always a possibility that someone has incorrectly applied RegEM, or PCA, or other numeric techniques; perhaps their forward computation is incorrect, or their error formulation is wrong – but if you’re going to do that, you have to demonstrate the particular issues with their work. And if you’re going to do that, you need to be talking about the technique(s) they actually used…

    REPLY: You are correct, its RegEm. My point is that they sought help from Mann on this paper, and statistical methodology has been shown to be lacking in both MBH98 and Steig 09.

    UPDATE: Actually you are not quite correct, but I have made a clarifying update: Note this from Steig et al 2009:

    Principal component analysis of the weather station data produces results similar to those of the satellite data analysis, yielding three separable principal components. We therefore used the RegEM algorithm with a cut-off parameter k=3…. A disadvantage of excluding higher-order terms (k>3) is that this fails to fully capture the variance in the Antarctic Peninsula region. We accept this tradeoff because the Peninsula is already the best-observed region of the Antarctic.

    Clearly, there was some PCA work done, but RegEm is the main method. The point is that the method produces an erroneous manufactured result, smearing peninsula data over the entire continent, which is not representative of reality. – Anthony

  12. TomRude says:

    Indeed the Orsi et al. 2012 paper says the LIA was a Global Event… Thanks Eric for pointing us to their paper…
    BTW in the post, the relation between Steig’s affirmation and the Orsi paper is not clear: in what sense is Orsi’s paper supposed to contradict O’Donnell?

  13. Matt G says:

    Haha, a single borehole temperature reconstruction at a single point is now more accurate than instrumental data. Who would have thought that the scence in climate science couldn’t get any more non science? If this is not an example of who has the biggest agenda then what is?

  14. Latimer Alder says:

    Alex says

    the science community should embrace an electronic forum system where vigorous debate and hypothesis testing/proposing can occur real-time and PUBLICLY.

    That’s how it all started at, for example, The Royal Society. Lectures and demonstrations were public events with real time debate. Journals only grew up because of the geographical impossibility of shifting people around, And the current model of journal publication assumes that it is paper based and that moving paper around is an expensive and time-consuming operation. Hence the need for the heavily devalued peer-review system and the enormously unwieldy mechanism of paper/counter paper/addendum etc which take months or years to settle questions that could be done in minutes face-to-face.

    But the miracle of the internet frees us from nearly all of those geographical and technological limitations. You can have (near) real time public conversations with participants anywhere in the world. This forum is a fine example.

    It is not the mechanism that is now the limitation…it is the willingness of the participants to use the new possibilities. And it is reasonable to assume that anybody who shies away from public debate has only a weak case and prefers assertion and table thumping to putting their work under tough scrutiny.

    I think we can all identify some (in)famous academic climateers who are reluctant to do so.

  15. markstoval says:

    “This is something that needs wides circulation” — should be “wider” I think.

    [Fixed, thanks. ~dbs, mod.]

  16. vukcevic says:
    September 8, 2012 at 8:50 am
    Antarctic’s magnetic field decadal change and the sunspot magnetic activity (from which the TSI is derived), show good correlation
    The TSI of Lean 2007 does not represent the real variation of the sunspot magnetic activity, so your correlation is spurious.

  17. Yancey Ward says:

    Alex asked:

    Why is it that such simple and obvious realities and deceptions are allowed to hang out there as “credible” in a science community?

    As a scientist myself, I learned one thing pretty early on in my career that was at odds to the conventional, public perception of science and it’s practioners: that science is a human endeavor, and, as such, is subject to the exact same biases and corruptions that are found in every other human endeavor. There is nothing special about science that makes it less open to corruptors and liars.

  18. If I may suggest
    Add large colored dots;
    This shows results best
    At thermometer spots.
    A blue spot on Steig’s
    Red field of high heat:
    Such contrast intrigues
    And shows the deceit.

    ===|==============/ Keith DeHavelle

  19. vukcevic says:

    Leif Svalgaard says: September 8, 2012 at 9:36 am
    The TSI of Lean 2007 does not represent the real variation of the sunspot magnetic activity

    Sorry about that, my bad, I have rearranged order, with L. Svalgaard’s TSI reconstruction now at the top, in order to give more accurate and up to date correlation.
    http://www.vukcevic.talktalk.net/TMC.htm

  20. Nic Lewis says:

    TomRude wrote:
    “in what sense is Orsi’s paper supposed to contradict O’Donnell”.

    You might well ask. Steig’s Guardian letter clearly implies that, in his mind, Orsi’s single-borehole surface temperature reconstruction proves that the O’Donnell, Lewis, McIntyre & Connon estimate of overall Antarctic warming is wrong. That a single point proxy temperature reconstruction can prove an multi-meteorological station based estimate for the whole continent wrong seems completely misconceived to me.

    BTW, the Orsi reconstruction trend for the 20 years to 2007 is 0.80 deg.C/decade. Satellite AVHRR temperature measurements exist for that period and – although they also are Inaccurate – can be used as a check on Orsi’s trend . Steig’s own cloudmasked AVHRR data (ending one year earlier) shows post 1986 trends of 0.15 and 0.12 deg.C/decade for the two grid cells closest to Orsi’s borehole- a fraction of Orsi’s 0.80 deg.C/decade estimate.

  21. Les Johnson says:

    Some points on Orsi. His Figure 3 shows warming of about 1.5 deg since the 80s. I believe this is what Steig is happy about.

    The problem, though, is that Figure 3 shows no warming from 1957 to about about 1980. Steig said there was a warming of about 0.5 deg/decade from 1957 (correct me if the dates are wrong). That would make warming of about 2.6 deg warming to 2009 (2.15 deg to 2000). Not the 1.5 deg measured by Orsi to 2000. Orsi’s start date is moot, as he shows no warming 1900-1980.

    Thus, Orsi validates O’donnel 2010 (O10), as O10 shows about 0.25 deg/decade of warming from 1957, in the location of the WAIS Divide. (yellow, 0.25 deg/decade, in the temperature scale for O10; red and 0.5 deg/decade for Steig09). O10 would give a warming of 0.25 deg/decade, vs Orsi’s 0.35, starting both from 1957.

    This is also totaly ignores the fact that Orsi shows no warming for over 20 years (1957-1980), but which Steig09 says did occur.

    Steig09 is actually proven wrong by the Orsi paper.Both in the amount of warming, and in the length of the warming, and in the slope of the warming. Orsi’s numbers are much closer to O10, except the slope.

    Granted, Orsi’s warming is about 0.75 deg/decade, but there is only two decades of warming in his record.

    Summary: From 1957, O10 shows 1.075 deg of warming to 2000. Steig09 shows 2.15 deg. Orsi’s measured warming from 1957 is 1.5 deg to 2000. O10 (-28% low) is closer to Orsi than Steig (+43% high).

    caveat: most of the numbers I use are eyeballed, albeit using a ruler for Orsi and figure 3.

  22. Craig Moore says:

    Instead of this —-> o <—-, perhaps it should be this )*(

  23. Gary Pearse says:

    “What normal thinking person would take a temperature from a lousy borehole and hold that out as superior to an actual thermometer?”

    A post normal person?

    Yancey Ward says:
    September 8, 2012 at 9:42 am
    “There is nothing special about science that makes it less open to corruptors and liars.”

    I have suggested that scientists must be disciplined by a professional association that can discipline or bar its members from practicing in extreme cases of incompetence and abuse. It works for engineers who have to be on their toes when they build a bridge or a space shuttle or just about everything that isn’t built by nature. Non sequitur: there is no such thing as a rocket scientist – only an engineer does this kind of work.

  24. Smokey says:

    There are greater temperature fluctuations at the higher latitudes. Thus, the equator is much more stable than the poles. So we would expect polar temperatures to vary [as they are doing now, especially in the Arctic].

    But globally there is very little change. This is what the alarmist crowd is running around in circles and hand-wringing about. As any rational person can see, runaway global warming is trumped up nonsense. And Steig is riding the gravy train by falsifying reality. Shame on hiim.

  25. gringojay says:

    Bore hole verses READER (Reference Antarctic Data for Environmental Research) …:
    READER data (as of 2005) from 11 sites showed warming & 7 sites showed cooling,
    verses Bore hole from 1 site showed warming & warmer yellow snow nearby.

  26. vukcevic says:

    I am certain that Dr. Steig is (or maybe not) aware of something called ‘polar amplification’ whereby surface temperature in the polar areas varies to much larger extent than at lower latitudes.
    http://www.vukcevic.talktalk.net/PA.htm
    Polar amplification makes temperature within polar areas less stable not only from point to point geographically but also in time.

  27. Don Keiller says:

    Tell me again, just how did Steig obtain his doctorate?
    Did he buy it from some dodgy, one room college?
    Can’t see any other option, because he certainly doesn’t do maths or science very well.

  28. TomRude says:

    @ Nic Lewis, thank you for your time and clear answer.

  29. Peter Foster says:

    Some time back there was a posting on WUWT about a type of thermometer being installed widely across the Antarctic peninsula that allowed reflected radiation to hit the sensor causing readings up to 10°C above the actual temp..
    Has the record ever been corrected for this or do the temperature analyses of the peninsula still use this faulty data ?

  30. Oscar Bajner says:

    Over at Bishop Hill I read of the CookBook club of the month who regard themselves as Spartans holding back the WUWTatian “hordes”.

    When the next Climate Change movie comes out I suggest they use Nelson, not Leonidas, as the template:
    One tree,
    One borehole,
    One trick
    Theme music by Whitney: Didn’t we almost have it all”

  31. vukcevic says:

    Leif Svalgaard says: September 8, 2012 at 9:13 am
    There is a certain entertainment value in your stuff

    Perhaps Ms Dickey from JPL and I should team up and form an entertainment duo perhaps on lines the ‘Hansen-Mann’ troupe.
    Jean Dickey of NASA’s Jet Propulsion Laboratory, Pasadena:
    Other possibilities are that some other Earth’s core process (where Earth’s magnetic field originates) could be having a more indirect effect on climate, or that an external (e.g. solar) process affects the core and climate simultaneously.
    http://www.vukcevic.talktalk.net/TMC.htm

  32. Dr Burns says:

    Sounds like arguing whether my house is warming or cooling when the temperatures of the oven, hotplates and refrigerator are included.

  33. vukcevic says:
    September 8, 2012 at 2:16 pm
    that an external (e.g. solar) process affects the core and climate
    Just shows how little Dickey understands of this.
    But that hardly matters when the correlation is spurious to begin with. As I said many a time, a spurious correlation does not need explanation or closer examination [except perhaps of the proposer's head].

  34. jim says:

    But since we know from everywhere and everything else that GLOBAL WARMING IS REAL, then S09 must be right! We KNOW IT FROM EVERYTHING ELSE SO IT’S RIGHT!

    GLOBAL WARMING IS REAL! IT MUST BE RIGHT!!!! MUST…MUST…BE…RIGHT!!

    WARMING REAL! MUST BE RIGHT! WARMING REAL! MUST BE RIGHT! MUSSSTTT BEEE RIGHHTTTTTTTTTTT!!!!

    sarc

  35. Bill Illis says:

    The Borehole Temperature reconstruction method is seriously flawed in some manner.

    Just compare the Borehole temperature reconstruction method for Greenland versus the published Antarctica Epica Dome C temperatures from the dO18 isotopes.

    Greenland got to -25.0C in the ice ages versus -10.0C in Antarctica while polar amplification (2X the global climate change) should work very similar in both places.

    Greenland got to +8.0C 123,000 years ago in the Borehole method while Antarctica was only +1.0C. [At +8.0C, the glaciers should have completely melted out in Greenland, especially considering the fact that 128,000 years ago was even warmer - the Greenland isotopes don't go back far enough to hit what was the peak temperature period in the Eemian interglacial at 128,000 years ago - who knows what the borehole method would have produced; +13.0C or so].

    The methodology is just not sound.

    http://s14.postimage.org/wxf5d348h/Greenland_Borehole_vs_Antarctica.png

  36. richcar 1225 says:

    Antarctica is currently one giant anti cyclone on steroids. The SAM index is near a record high meaning the interior plateau is at record cold and high pressure compared to the sub tropics resulting in Katabatic westerly winds (coriolis efffect) roaring around the continent dragging the circumpolar current with it resulting in record upwelling at the Polar front which is resulting in the coldest Southern ocean since 1980. Of course Steig amazingly blames this on the ozone hole that should have disapeared by now due to the Montreal protocol. The Antarctic Pennisula warming is simply due to Katabatic downsloping winds not ocean SST. I believe there is likely a solar connection between the ozone hole and the strength of the anti cyclonic winds.
    Southern Ocean SST:
    http://bobtisdale.files.wordpress.com/2012/08/13-southern.png

  37. pat says:

    The fact that these ‘scientists’ simply refuse to report that Antarctica is cooling, and has been for decades, with the exception of the Peninsula is simply disgusting. They have turned climatology into phrenology.

  38. Brian H says:

    When in a deep borehole with the sides collapsing, stop digging. Or drilling.

  39. Ninderthana says:

    Some people [e.g. Leif] are blind to what they don’t know because of all the knowledge that they do know.

  40. “…We therefore used the RegEM algorithm with a cut-off parameter k=3…A disadvantage of excluding higher-order terms (k>3) is that this fails to fully capture the variance in the Antarctic Peninsula region. We accept this tradeoff because the Peninsula is already the best-observed region of the Antarctic…”

    First off, I’ll agree that “the Peninsula is already the best-observed region of the Antarctic”, because we’ve now seen Steig et al (2009), O’Donnel et al 2010 and Orsi et al (2012) – and I’m sure that we’ll see a rebuttal to the Orsi paper, too.

    But it’s that first part that makes me wonder – if choice of the parameters is so critical (going from k=3 to k=>3) that use of higher-order terms fails to fully capture the variance in the Antarctic Peninsula, then how strong was the variance?

    It sounds like they used the lowest cut-off they could that still showed the Peninsula region’s warming – not really caring how the rest of the CONTINENT fared.

    I hope somebody can replicate this study. I’d really love to see the “maps” with different parameters plugged in (for example, what’s the difference between k=3 and k=3.1).

  41. richcar 1225 says:

    This is the current reality of cold in Antarctica that is as much as 10 degrees C below the 1998-2006 average.
    http://www.climate4you.com/images/ANTARCTIC%20Temp%20201207%20versus%201998-2006%201200km.gif
    Where are the headlines about this.

  42. jorgekafkazar says:

    richcar 1225 says: “…The Antarctic Pennisula warming is simply due to Katabatic downsloping winds not ocean SST.”

    Isn’t there significant volcanic activity in and around the peninsula?

  43. geo says:

    Oy. Any port in a storm for Steig, eh? Accept the LIA was global and probably volcanic or solar. . . except that also means the temp rise was significantly impacted by rebound from natural variation, and so not so terribly interesting as proof of AGW, particulary future extrapolation of AGW. How. . . .unprincipled.

  44. Rob Dekker says:

    Bill Illis said :

    Greenland got to -25.0C in the ice ages versus -10.0C in Antarctica while polar amplification (2X the global climate change) should work very similar in both places.

    Where did you get that idea from ? Why should the Arctic and the Antarctic show the same polar amplification, Bill ?

  45. Rob Dekker says:

    I’m sorry if I missed the hoopla.
    Did O’Donnell et al conclude that Antarctica is cooling ?

  46. Rob Dekker says:

    Jeff Condon wrote (in the original post) :

    Unfortunately for us, the article itself has been updated in response so we can’t read the original.

    Sorry, Jeff, but your are confusing the Antarctic for the Arctic.
    The post with the letter from Eric is still where it has been since it was posted :
    http://www.guardian.co.uk/environment/2012/sep/06/antarctic-warming-sea-levels?newsfeed=true

  47. Rob Dekker:

    At September 9, 2012 at 1:13 am you ask Bill Illis:

    Why should the Arctic and the Antarctic show the same polar amplification, Bill ?

    I cannot answer for Bill Illis, but I know where I got it from: it was the UN Intergovernmental Panel on Climate Change (IPCC) Working Group 1 (WG1: i.e. the “science”).

    The IPCC First and Second Assessment Reports provided plots of climate model ‘projections’ which showed it. And no IPCC report has said otherwise since.

    Richard

  48. DirkH says:

    Rob Dekker says:
    September 9, 2012 at 2:32 am

    “Sorry, Jeff, but your are confusing the Antarctic for the Arctic.
    The post with the letter from Eric is still where it has been since it was posted :”

    Reading comprehension, Rob. The article by John Vidal to which Nic Lewis responded has been updated, not Steigs letter.

    “Eric Steig has written a letter to “The Guardian” (booming voice) in response to a Nic Lewis letter patiently explaining problems in an article written by yet-another-know-nothing with a keyboard. Unfortunately for us, the article itself has been updated in response so we can’t read the original. “

  49. DirkH says:

    And of course there is STILL pretty funny stuff in the Grauniad article.

    “North Pole webcam picture taken on 22 August 2012 showing ice cap melting. Climate scientists expect the Arctic sea ice is on course to plummet to its lowest levels ever this weekend.”

    In other words, Climate scientists expect the Arctic is on course to become ice-free this weekend. says the Grauniad. As that is the lowest historical level of arctic sea ice; zero.

  50. kretchetov says:

    “Dr Burns says:
    September 8, 2012 at 2:18 pm

    Sounds like arguing whether my house is warming or cooling when the temperatures of the oven, hotplates and refrigerator are included.”

    Yes, that is exactly right. Now try and establish the average temperature of your house, including all of the above, relying on thermometers placed near the oven, and establish the historic averages by taking a single core from a wooden door in the basement to come up with a proxy.
    Show that the proxy was about -20 deg 50 years ago, ignoring common sense, and that the current temperatures are about +20 deg, extrapolate exponentially 100 years into the future, and announce to your family that you should be able to cook dinners 5 years from now using ambient temperature inside your house, which by then be hot enough to melt steel…

  51. kretchetov says:

    \”Dr Burns says:
    September 8, 2012 at 2:18 pm

    Sounds like arguing whether my house is warming or cooling when the temperatures of the oven, hotplates and refrigerator are included.\”

    Yes, that is exactly right. Now try and establish the average temperature of your house, including all of the above, relying on thermometers placed near the oven, and establish the historic averages by taking a single core from a wooden door in the basement to come up with a proxy.
    Show that the proxy was about -20 deg 50 years ago, ignoring common sense, and that the current temperatures are about +20 deg, extrapolate exponentially 100 years into the future, and announce to your family that you should be able to cook dinners 5 years from now using ambient temperature inside your house, which by then be hot enough to melt steel…

  52. Jeff Condon says:

    Thanks Anthony and everyone. There were a few questions about Orsi’s support of Steig.

    This quote is in the conclusion of Orsi:

    “This record also confirms the work of Steig et al.
    [2009], showing that WAIS Divide has been warming by
    0.23  0.08 C per decade over 1957–2007 C.E.”

    Which is what earned him an honorable mention in the post. Just because nonsense math resulted in a similar slope to other nonsense math, doesn’t mean it confirms anything.

    Rob Dekker says:
    September 9, 2012 at 2:32 am

    Rob, I was referring to the original news article Nic commented on and is linked in “yet another know nothing”. Perhaps I missed something but below is a quote from the article:

    “• This article was amended on 24 August 2012 to restore to the start of the penultimate paragraph the words “Research published in Nature today”, which had been lost in the editing process, and to clarify that the research was about temperatures in the Antarctic peninsula.”

  53. Matt says:

    News from the Arctic, too:
    Arctic ice cap is “heading for oblivion.”

    http://www.bbc.co.uk/news/science-environment-19496674

  54. Les Johnson says:

    Jeff: If I am reading the colors right, your paper gives a 0.25 deg/decade warming (yellow) in the area of the WAIS Divide. (79 deg S, 112 deg W)

    Steig shows 0.5 degree/decade in his (red).

    This also matches fairly well with my back of the envelope calculations, above.

    Orsi shows your paper to be correct, not Steigs!

  55. RobW says:

    Try this at home. Squint your eyes, tilt your head (best after a night of heavy drinking) and you can almost see the growth rings in the boreholes. Presto ——All of Antarctica is Warming

  56. Jeff Condon says:

    Les, I haven’t tried it with the actual data but you may be right.

  57. clipe says:

    Speaking of “boreholes” Peter Gorrie took the 2007 prize.

    Gorrie: Arctic discovery confirms impact of global warming
    Published on Friday August 06, 2010
    HMS Investigator doomed in the pack ice of Mercy Bay, 1850, as painted by ship’s officer Samuel Gurney Cresswell.
    Image
    By Peter Gorrie Environment Columnist

    It’s no wonder Ottawa won’t do anything to reduce climate change. The warming Earth has made a dream come true for federal Environment Minister Jim Prentice.

    “I’m elated,” Prentice is reported to have exclaimed when informed HMS Investigator, a British ship that sank 155 years ago while searching for Sir John Franklin’s doomed Northwest Passage expedition, had been found in the cold western Arctic Ocean.

    Parks Canada staff had no trouble finding the well-preserved remains of the 400-tonne vessel with the ocean ice-free this summer — a situation first reported only in 2007.

    Prentice is apparently an Investigator buff, and reviewed a book about its unsuccessful voyage last winter. Had the ocean remained frozen, the ship would continue to rest unseen, 11 metres below the surface.

    Climate change will unseal many other Arctic treasures over the next few years. Most important — less romantic but incomparably more lucrative than an old boat — are oil and gas deposits.

    http://www.thestar.com/news/insight/article/843898–gorrie-arctic-discovery-confirms-impact-of-global-warming

    So HMS Investigator has always been frozen in ice?

    Recent news which reminded Gorrie’s piece.

    http://www.cbc.ca/news/canada/story/2012/09/07/f-franklin-search.html

  58. clipe says:

    2010 Prize

  59. clipe says:

    Correction ↑

    Recent news which reminded me of Gorrie’s piece.

  60. clipe says:

    I’m OT but bear with me.

    “Even though it’s not terribly deep, it’s only 20, 30 sometimes upwards of 50 metres in the areas we’ve been looking, the ice doesn’t seem to be getting down that deep and significantly affecting the seafloor,” says Harris.

    “So a wreck in that area would probably stand to be very well preserved, perhaps perfectly intact like the wreck of Investigator.”

    http://www.cbc.ca/news/canada/story/2012/09/07/f-franklin-search.html

  61. ferdberple says:

    vukcevic says:
    September 8, 2012 at 8:50 am

    Antarctic ice cover rising, solar magnetic activity falling, any connection?
    Still trying to understand what mechanism can be responsible and what consequences for the Antarctic and S. Hemisphere temperature might be.
    =============
    The solar wind entering the atmosphere at the magnetic poles is the mechanism. Where is the evidence that this is simply co-incidence?

    The paleo records clearly show that climate change is associated with changes to the earth’s magnetic field. We are in a period of very rapid change in the magnetic field. We are experiencing climate change.

    A much stronger case can be made that CO2 and climate change is simply coincidence, because the paleo records show that CO2 lags temperature.

  62. ferdberple says:

    Leif Svalgaard says:
    September 8, 2012 at 2:29 pm
    But that hardly matters when the correlation is spurious to begin with. As I said many a time, a spurious correlation does not need explanation or closer examination
    ========
    Whether a correlation is spurious or not cannot be determined without examination. Many correlations have been proclaimed to be spurious in the past, by very knowledgeable and learned people, only to later have been found to be due to cause and effect.

    Continental drift, Milankovitch cycles for example. The problem is that our mathematics is extremely weak when analyzing non-linear interactions, making it extremely difficult to establish cause and effect for non-linear multivariate problems.

    Unless spurious correlations are examined in light of new knowledge, history shows that many scientific discoveries will be missed. What may appear spurious today may simply be an artifact of our limited understanding.

  63. Crispin in Waterloo says:

    @richcar 1225

    “Antarctica is currently one giant anti cyclone on steroids. The SAM index is near a record high meaning the interior plateau is at record cold and high pressure compared to the sub tropics resulting in Katabatic westerly winds (coriolis efffect) roaring around the continent dragging the circumpolar current with it resulting in record upwelling at the Polar front which is resulting in the coldest Southern ocean since 1980.”

    I am not sure if you saw the paper I referenced on the South Pole temperature, for Kevin the warmist on another thread. The air temperature on the ground is strongly affected by the surface wind speed. As the air temperature rises with altitude additional stirring raises the temperature recorded on the surface.

    This means that the surface temperature may be nothing more than a good proxy for the wind speed, not a particularly good source of knowledge about melting or warming.

    This means all the authors could claim that all lower temps are cause by lower wind speeds or all higher temps are caused by higher speeds. Similar arguments are available regarding top-of-ocean temperatures on the peninsula and the adjacent land. The only thing that seems to be sure is that the overall ice volume on land is increasing especially in the east.

    If the low winds persist in the center the temperatures will continue to remain lower than the historical average, whether or not there is any polar amplification. I agree with the comment that the IPCC says both poles will warm, according to their understanding – a prognostication clearly at variance with reality .

  64. Alan Esworthy says:

    “What it shares with PCA is that it is an iterative refinement method, a gradient descent fitting method, honing in on an answer by reducing error terms at each iteration.”

    I almost stopped reading right there. Anyone who writes “honing in” when he means “homing in” is guilty of sloppy thinking at best. Is it unreasonable of me to suspect sloppy thinking elsewhere?

  65. Rob Dekker says:

    With all this O’Donnell chest beating and Steig bashing going around here at WUWT, may I humbly point out that borehole temperatures are highly smoothed by diffusion, and the farther back in time, the greater the diffusion. In the case of Orsi et al, the most accurate and unambiguous part of their reconstruction is that past 20 years (since 1990) over which Orsi et al shows a whopping +0.75 C/decade temperature rise on the WAIS divide, consistent with Byrd station data.

  66. Rob Dekker says:

    richardscourtney said

    Rob Dekker:

    At September 9, 2012 at 1:13 am you ask Bill Illis:

    Why should the Arctic and the Antarctic show the same polar amplification, Bill ?

    I cannot answer for Bill Illis, but I know where I got it from: it was the UN Intergovernmental Panel on Climate Change (IPCC) Working Group 1 (WG1: i.e. the “science”).

    The IPCC First and Second Assessment Reports provided plots of climate model ‘projections’ which showed it. And no IPCC report has said otherwise since.

    Richard, are deliberately vague or did you accidentally forget to point out where exactly in the UN IPCC WG 1 reports “it” is shown that the Arctic and Antarctic show the same polar amplification ? If you can’t find it in AR4 and have to go all the way back to AR 1 or AR 2, that’s fine. But at least present your evidence rather than handwaving at “plots of climate model ‘projections’”.

  67. Rob Dekker says:

    Jeff Condon said :

    Les, I haven’t tried it with the actual data but you may be right.

    Maybe you should use Orsi et al data, Jeff. That borehole is right in the area where O’Donnell et al had only a single station to work with within a 1000 km radius : Byrd.

    Reconstructions of the WAIS divide temperature trend are seriously hampered by a lack of station data.
    In fact, the station at Byrd (80°S, 120°W) is the only one around that area, and for that becomes crucial in determining trends for the WAIS divide and the West Antarctic in general.

    To make matters worse, since Byrd actually consists of two temporarily non-overlapping stations (separated by a decade of no data) the main factor that determines the trend at Byrd is how you calculate the offset between the two stations.

    Raw data trend (assuming no offset between the two stations) obtains +0.38 C/decade and Monaghan et al obtained +0.32 C/decade at the Byrd location.
    Steig et al used AVHRR satellite data to calculate the offset, and came up with a +0.25 C/decade trend at Byrd.
    O’Donnell used trends at the closest nearby stations (which were about 1000 miles away) and came up with a +0.08 C/decade trend at Byrd.

    Since the difference in trend at Byrd is so important for the determination of WAIS and West Antarctica reconstructions, the issue of Byrd became a major point of contention between O’Donnell and Steig :
    http://www.realclimate.org/index.php/archives/2011/02/west-antarctica-still-warming-2/

    Now Orsi et al drilled a borehole fairly close to Byrd (at 79.5°S, 112°W), and they obtain a trend of about +0.3 C/decade at their location. And, as I mentioned before, Orsi et al shows most (if not all) of that warming to occur since 1990 (as did Steig’s analysis).

    So, Jeff, since the offset calculated for the Byrd old and new stations is so important in reconstructing WAIS and West Antarctic temperature fields, and O’Donnell et al had no station nearby to calibrate the offset at Byrd, maybe it would be a good idea to enter the Orsi et al data in O’Donnell’s method (as if it is a new station with a 50 year uninterrupted record), and see how if that changes the reconstructed temperature field, the trends, the uncertainties and maybe even the conclusions of the O’Donnell paper.

    Wouldn’t that be an interesting thing to try, Jeff ?

  68. richardscourtney says:

    Rob Dekker:

    You made an untrue assertion in the form of a question that I answered. So, having been shown to be wrong, at September 10, 2012 at 1:39 am you provide the usual response of a warmist when exposed as having presented a falsehood: i.e you lie and smear with innuendo.

    I wrote

    The IPCC First and Second Assessment Reports provided plots of climate model ‘projections’ which showed it. And no IPCC report has said otherwise since.

    Your response says

    Richard, are deliberately vague or did you accidentally forget to point out where exactly in the UN IPCC WG 1 reports “it” is shown that the Arctic and Antarctic show the same polar amplification ? If you can’t find it in AR4 and have to go all the way back to AR 1 or AR 2, that’s fine. But at least present your evidence rather than handwaving at “plots of climate model ‘projections’”.

    Armwaving!?
    The plots are part of Chapter 5 titled “Equilibrium Climate Change – and its Implications for the Future” in the First IPCC Report. They are Figures 5.4 (a) to (f) in the Section of the Report by Working Group 1 (i.e. the ‘science’ report). The chapter considers the plots to be so important that it provides two versions of Figure 5.4: a monochrome version is on pages 141 and 142 with a colour version on pages 164 and 165. And the chapter provides similar plots from other projections as Figure 5.2 on page 140 and they also give the same indication.

    This is WUWT and not some warmist ‘echo chamber’. Sensible people would not dream of making your mistakes by making statements they cannot justify on WUWT.

    Do you want to continue this discussion? It seems you want a gunfight when your only armament is a toothbrush.

    Richard

  69. richardscourtney says:

    Moderator:

    In my recent reply to Rob Dekker I have used a [START of block quote] where I intended an [END of block quote].

    My mistake is after the sentence
    But at least present your evidence rather than handwaving at “plots of climate model ‘projections’”.

    In addition to spoiling the formatting of my post, I fear it may affect formatting of subsequent posts. Sorry.

    I would be grateful if you were to correct my mistake.

    Richard

  70. Nic Lewis says:

    Rob Dekker wrote:
    “So, Jeff, since the offset calculated for the Byrd old and new stations is so important in reconstructing WAIS and West Antarctic temperature fields, and O’Donnell et al had no station nearby to calibrate the offset at Byrd, maybe it would be a good idea to enter the Orsi et al data in O’Donnell’s method (as if it is a new station with a 50 year uninterrupted record), and see how if that changes the reconstructed temperature field, the trends, the uncertainties and maybe even the conclusions of the O’Donnell paper. ”

    As I wrote earlier, the Orsi reconstruction trend for the 20 years to 2007 is 0.80 deg.C/decade. Satellite AVHRR temperature measurements exist for that period and – although they also are inaccurate – can be used as a check on Orsi’s trend . Steig’s own cloudmasked AVHRR data (ending one year earlier) shows post 1986 trends of 0.15 and 0.12 deg.C/decade for the two grid cells closest to Orsi’s borehole- a fraction of Orsi’s 0.80 deg.C/decade estimate. That does not give one any confidence in the accuracy of Orsi’s temperature reconstruction. Nor does the fact that he compared his results with those in a AVHRR grid cell that, although near the WAIS divide, was neither the grid cell containing his borehole nor the adjoining grid cell with the closest border thereto.

    The AVHRR trend for the same period (1987 to 31 December 2006) in the grid cell containing Byrd is even lower than that either grid cell closest to the Orsi borehole.

    The 1957-2006 OLMC main reconstruction trend at Byrd is actually 50% greater than that per the Steig et al 2009 reconstruction, and HIGHER than Orsi’s borehole trend for the 50 years to 2007 of 0.23 C/decade. So, on that basis, adding the Orsi data would if anything reduce the OLMC West Antarctica reconstruction trend.

    Since West Antarctica only makes up a little over 20% of the continent, the temperature trend for Antarctica as a whole is relatively little affected by the West Antarctica trend. It was the trend for the whole continent that the Guardian article, and the claim in Steig’s letter that OLMC had been proven wrong, concerned: he wrote “… his [i.e, my] letter also refers to an outdated study of his, which argued that previous estimates of overall Antarctic warming were too high. In fact, the work of Lewis and co-authors has been proven wrong.”

    It is a pity that a highly experienced climate scientist like Professor Steig appears to have so little regard for the facts.

    There is a huge difference between a borehole temperature reconstruction and an instrumental measurement air temperature record. It is indeed unfortunate that there are two separate weather stations at Byrd, with a long gap between them. There is no real justification for stitching their records together with no offset as Steig did in his 2011 blog post.

  71. Rob Dekker says:

    Nic Lewis said :

    The 1957-2006 OLMC main reconstruction trend at Byrd is actually 50% greater than that per the Steig et al 2009 reconstruction, and HIGHER than Orsi’s borehole trend for the 50 years to 2007 of 0.23 C/decade.

    That does not sound quite right Nic.
    According to the trend plot (“without the satellites the temperature stations alone say this”) in Jeff Condon’s post here, the trend at Byrd (80°S, 120°W) is something like 0.1 C/decade.

    Similarly, Eric Steig presented that the O’Donnell et al reconstructs the 50 year trend at Byrd at +0.08 C/decade :
    http://www.realclimate.org/index.php/archives/2011/02/west-antarctica-still-warming-2/
    and again here :
    http://www.realclimate.org/index.php/archives/2012/05/fresh-hockey-sticks-from-the-southern-hemisphere/

    Question for you : Is Eric right ? And if not, what IS the 50 year trend a Byrd that O’Donnell reconstructed ?

    Second, you wrote :

    Since West Antarctica only makes up a little over 20% of the continent, the temperature trend for Antarctica as a whole is relatively little affected by the West Antarctica trend.

    Well, let’s look at that assertion for a second :

    If the real 50 year trend at Byrd is +0.38 C/decade (raw data) or +0.32 C/decade (Monaghan et al) or +0.25 C/decade (Steig et al) or closely matches WAIS borehole data +0.23 C/decade (Orsi et al), and NOT the +0.08 C/decade that O’Donnell et al obtained, then you have underestimated the trend at Byrd wrong by at least 0.15 C/decade.

    Since Byrd is the ONLY record of any length anywhere in West Antarctica, if you get the Byrd trend wrong, you get the whole of West Antarctica wrong.

    Thus, if you had West Antarctica wrong by 0.15 C/decade, then you get the entire continent trend wrong by about 0.15/5 = 0.03 C/decade. Which would change the O’Donnell et al 2010 continental trend from +0.06 +/- 0.08 C/decade to +0.09 +/-0.08 C/decade.

    Which would mean that O’Donnell et al 2010 no longer can claim that Antarctica is not warming significantly.

    Yes. a single borehole temperature reconstruction at a single point can indeed change everything.

    So, yes, it’s kind of important that you explain what O’Donnell et al 2010 reconstructed at Byrd, exactly.

  72. Nic Lewis says:

    Rob Dekker,
    You wrote “Yes. a single borehole temperature reconstruction at a single point can indeed change everything.”

    My statement “The 1957-2006 OLMC main reconstruction trend at Byrd is actually 50% greater than that per the Steig et al 2009 reconstruction” was based on incorrect information. Apologies. However, you are iwrong in thinking that the trend for the whole of West Antarctica is very largely dependent on that at Byrd station (which itself may well be some way different from that at Orsi’s borehole location).

    The Steig 2009 reconstruction 1957-2006 trend at Orsi’s borehole location is between 0.23 and 0.24 C/decade, close to Orsi’s own 50 year trend of 0.23 – not that their agreement proves anything at all. The OLMC reconstruction 1957-2006 trend at Orsi’s borehole location is 0.13 C/decade below the mean of Steig’s and Orsi’s trends. Increasing the OLMC trend of the (infilled) Byrd station record by 0.13 C/decade to reflect that difference would leave the overall OLMC 1957-2006 continental trend below 0.07 C/decade – still insignificant. Such an increase of 0.13 C/decade would take the OLMC infilled trend at Byrd above the corresponding Steig et al 2009 trend – although there is very little reason to think Steig’s mathematically-flawed estimate is better than the OLMC estimate.

    Even leaving out the OLMC results, the huge differences between Orsi’s post 20 year to 2007 borehole reconstruction trend of 0.80 C/decade and the trend at Orsi’s borehole location both per the AVHRR data (circa 0.15) and per the Steig 2009 reconstruction from end 1987 to end 1986 (0.12 C/decade), point to the Orsi reconstruction being wildly inaccurate.

  73. Nic Lewis says:

    A couple of typos. In the first line of the final paragaph above, “Even leaving out the OLMC results, the huge differences between Orsi’s post”, the word “post” should not appear. Also, in paragraph two, “iwrong” should read “wrong”.

  74. Rob Dekker says:

    Nic Lewis said

    The OLMC reconstruction 1957-2006 trend at Orsi’s borehole location is 0.13 C/decade below the mean of Steig’s and Orsi’s trends. Increasing the OLMC trend of the (infilled) Byrd station record by 0.13 C/decade to reflect that difference would leave the overall OLMC 1957-2006 continental trend below 0.07 C/decade – still insignificant.

    Thank you for confirming that the trend at the Orsi et al WAIS divide location in O’Donnell et al is around +0.1 C/decade, and for estimating how much the effect Orsi et al borehole measured +0.23 C/decade trend could affect the end-results of O’Donnell et al. If the continental trend becomes +0.07 +/- 0.08 C/decade, the result is indeed still insignificant, although by an arguably uncomfortable small margin.

    Such an increase of 0.13 C/decade would take the OLMC infilled trend at Byrd above the corresponding Steig et al 2009 trend

    How did you conclude that ? As far as I can see, the infilled trend at Byrd in O’Donnell et al is +0.08 C/decade. If I add 0.13 to that, I get +0.21 C/decade, which is still below Steig’s trend at Byrd of +0.23 C/decade, and certainly below the +0.32 C/decade trend at Byrd from Monaghan et al.

  75. Jeff Condon says:

    Rob Dekker says:
    September 10, 2012 at 2:43 am

    Jeff Condon said :

    Les, I haven’t tried it with the actual data but you may be right.
    Maybe you should use Orsi et al data, Jeff. That borehole is right in the area where O’Donnell et al had only a single station to work with within a 1000 km radius : Byrd.

    Rob,
    I’m sorry that I haven’t been back to look at this thread for a bit. I’m afraid that I suffer from the view that a borehole holds zero value with respect to temperature. Due to its numerous errors, I hold the same opinion of Steig’s result.

    As to your claim that Byrd is wrong so all of the west Antarctic is, you are missing a couple of points. First that Byrd station itself, from the BAS site, has a lot of missing data. Second, that PCA creates false resonances in the spatial temperature information. These show up as Chadni patterns in the result which tend to create localized mismatches in the data. Even though all PC’s were used in the reconstruction, it is my contention that noise in the data causes certain modes to remain prevalent in localized regions. Note the darker blue near Byrd. It is quite possible to get a region like Byrd to be slightly different than actual yet have it fully compensated by an adjacent region.

    An example of the regional mismatch in the west Antarctic can bee seen by swinging your eyes to the temperature by closest station plot provided in this post as the second figure from the bottom. It looks different in the Byrd region – slightly. There isn’t as much localized cooling in closest station method at the bottom edge of the Antarctic. What I can say is that the average of the West by O10 is almost exactly the same as the method-independent closest-station reconstruction even though there are minor regional differences.

    What is an artifact of the method vs actual weather pattern is impossible to determine. Therefore, even our corrected Steig method is not my preferred result but if you believe there is value in the improved spatial form of the satellite data because it incorporates natural weather patterns over boring closest station methods, the corrected Steig method might be your preferred result.

    My short version answer is that you are incorrect that if we get a different Byrd answer the West Antarctic is wrong. As evidence, the PCA West result is the same as the averaged temperature stations for the region.

    I’m sorry that I don’t have time to look at the data for you more on this. The data and full results are online at Climate Audit so you can find exactly the trend you want to locate.

    If time permits, I do hope to apply Roman’s anomaly methods and Kriging to the problem. That would create a far easier to understand temperature field. The noisy AVHRR satellite data could be used for determining appropriate distance weighting in the matrix.

    Kriging sounds like a boring publication but all of this noise from “climate scientists” about a single point in a reconstruction means that people are generally confused about PCA methods. While various principle component methods are the sexy thing to use these days in the field (on whatever random data can be found), these kinds of discussions by the pro’s tell me that they may not afford sufficient added value.

  76. Nic Lewis says:

    Rob Dekker wrote:
    “How did you conclude that ? As far as I can see, the infilled trend at Byrd in O’Donnell et al is +0.08 C/decade. If I add 0.13 to that, I get +0.21 C/decade, which is still below Steig’s trend at Byrd of +0.23 C/decade, and certainly below the +0.32 C/decade trend at Byrd from Monaghan et al.”

    Ah, you are confusing Steig’s reconstruction trend for the grid cell containing Byrd with Steig’s actual trend for the infilled Byrd station record – which he kept quiet about!

    Steig’s RegEM code infills the missing temperature data for the 42 manned weather stations that he uses for his reconstruction, plus for the 3 AVHRR satellite principal components (PCs). He then produces a spatial (grid cell based) reconstruction from just those 3 PCs, a very unsatisfactory procedure that has the effect of smearing the warming from the many peninsula stations over much of the continent. His spatial reconstruction is accordingly pretty much worthless, irrespective of the merits of his infilling procedure. That was a key point made in the OLMC paper: Steig’s reconstruction is invalid, since its method is mathematically unsatisfactory.

    The infilling method that Steig used was less sophisticated, and less stable, than that used by OLMC, and used fewer stations but included the 3 AVHRR PCs. Reflecting these differences, Steig’s 1957-2006 trend for the infilled Byrd station record was considerably higher than OLMC’s trend.

    However, Steig’s 1957-2006 trend for the infilled Byrd station record was only 0.135 C/decade, NOT 0.23 C/decade.

    I invite you to check this for yourself by running the relevant computer code on the data that Steig used. Or you can ask Eric Steig to check it, and thereby find out if he is as willing to provide information as the OLMC team have been.

    The large discrepancy between the trend per the infilled Byrd station record and the trend per the spatial reconstruction at the same location illustrates how poor Steig’s reconstruction was. The two trends are close to each other in OLMC’s case.

    Since Steig’s spatial reconstruction used only 3 PCs and thus had only 3 time series to define the temperature records for 5509 grid cells, and for various other reasons that you will be familiar with if you have read the OLMC paper, the Steig reconstruction trend in any particular grid cell is not very meaningful. That being so, in Steig’s case the trend for Byrd station itself, post infilling, is a much better measure of the trend at Byrd than the spatial reconstruction trend there.

  77. Rob Dekker says:

    Jeff Condon said

    As to your claim that Byrd is wrong so all of the west Antarctic is, you are missing a couple of points.
    First that Byrd station itself, from the BAS site, has a lot of missing data.

    We don’t disagree on that, Jeff, but if the issue at Byrd was only that it had a lot of missing data, then O’Donnell et al would have found a trend of +0.25 C/decade at Byrd (if I understand Ryan correctly). That would have resulted in a West Antarctica trend of +0.16 C/decade, getting pretty close to Steig’s reconstructed trend in West Antarctica, and a continental trend of +0.07 +/- 0.08 C, barely insignificant.

    But that did not happen, since O’Donnell modeled Byrd as 2 stations. That is reasonable, because there was a re-location at Byrd (from the old manned station to Byrd AGW, an automated station). But the problem then becomes on how you will calculate the “offset” between the two Byrd stations. O’Donnell et al used the nearest stations that cover the data void time period between the old and the new Byrd station, but these are more than a 1000 km away, across the Ross sea and beyond. Wouldn’t that cause data “smearing” at Byrd, and over West Antarctica, no matter which statistical method you use ?

    It’s simply very difficult to obtain data where there is none, right ?

    Now, when a lousy borehole comes along in exactly the right place, confirming the original trend (at +0.23 C/decade) would you not want to use that data to re-calibrate your offset at the two Byrd stations, and see what will come out for the O’Donnell et al conclusions ?

    Second, that PCA creates false resonances in the spatial temperature information. These show up as Chadni patterns in the result which tend to create localized mismatches in the data. Even though all PC’s were used in the reconstruction, it is my contention that noise in the data causes certain modes to remain prevalent in localized regions. Note the darker blue near Byrd. It is quite possible to get a region like Byrd to be slightly different than actual yet have it fully compensated by an adjacent region.

    Thanks for bringing up the “darker blue near Byrd” in the O’Donnell reconstruction. It seems to be not just near Byrd, but smearing out all across the South part of West Antarctica, extending to the Ross Sea shore. I was wondering where these came from, but your explanation of PCA creates false resonances in the spatial temperature information. These show up as Chadni patterns in the result which tend to create localized mismatches in the data is way over my head.

    Could you please explain in plain English which stations around the area are responsible for the “darker blue” ? Or if it was not station data, which data caused that part of West Antarctica to show up as cooling in the O’Donnell reconstruction ?

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