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How GISS Have Changed The Temperature Record Since 2008

January 17, 2013

By Paul Homewood


I ran a post yesterday, showing how the latest version of GISSTEMP had changed from using Hadley/Reynolds to ERSST for ocean temperatures, with the result that about 0.03C had been added to recent warming.

However, this is not the only change they have made to the historical temperature record in recent years. Climate4You, fortunately, archived the GISS data in May 2008. Comparing this dataset with today’s version, we can see that about 0.10C of warming, or more, has been added to temperatures in the last decade, compared to data up to about 1950.



Alterations to temperature record 1881-2007


It must be remembered that these are only changes made by GISS since 2008. As I pointed out, prior to 2008, other adjustments of about 0.03C had already been added to the numbers originally declared just a few years earlier. These adjustments must, therefore, also be added on to the adjustments made since.

An adjustment of 0.10C or so may not seem a lot, but the latest GISS anomaly, against the baseline of 1951-80, is 0.44C. These adjustments make up about a quarter of this figure.


I have also done some digging on the original numbers GISS declared for 1998, which seem much different to what they now show. News on this later.



[The graph heading should read 1881-2007, not 1881-2008 – now updated]

  1. Andy DC permalink
    January 18, 2013 12:48 am

    Another clear case of highly unscientific bias. To say these people are in the tank for AGW is an understatement.

  2. January 18, 2013 4:03 am

    Of course they need to fiddle the temperature books. The basic reason is …

    The automatic development of a vertical thermal gradient (AKA “lapse rate”) in any atmosphere in a gravitational field has been confirmed by over 800 experiments since 2002. It happens at the molecular level, regardless of the surface temperature or the amount of convection. Details are in “Planetary Surface Temperatures. A Discussion of Alternative Mechanisms.”

    This autonomous “lapse rate” fully explains that “33 degrees of warming” without any need for any greenhouse effect.

    All should read this comment by, Geoff Wood, qualified in astrophysics.

    The following are excerpts ..

    As Doug has said about a dozen times, gravity modifies the mean free path between collisions. That is ‘every’ upward, ‘every’ downward ‘every’ sideways, ‘every’, ‘every’ free molecular path between collisions is modified. Therefore it is impossible for the modified ‘collisions’ that result, not to impart the gravitational ‘information’ into the macroscopic development of the gravitational thermal profile. This is the ‘diffusion’ process.

    At this point, we have a reasonable depiction of the thermal profile of ANY atmosphere. FROM BASIC PHYSICS.

    Given a simple reason why any atmosphere tends towards this isentropic profile as depicted and described by entry level physics, why would anyone look for a more complicated reason to explain what we already know!

    The point which Geoff and I make is that the “33 degrees of warming” supposedly caused by water vapour and carbon dioxide etc was already there due to the effect of gravity on the atmosphere. This happens on all planets, and also fully explains why the poles of Venus are over 720K, even though they receive less than 1W/m^2 of direct insolation from the Sun. For more detail read my article “The 21st Century New Paradigm Shift in Climate Change Science” easily found with Google. I’ve also recorded an introductory 10 minute video here

    Doug Cotton

  3. January 18, 2013 7:11 am

    This seriously is criminal. Why are there no police for these people? The MSM should be all over this, too. Is EVERYONE a crim???

  4. Brian H permalink
    February 3, 2013 6:32 pm

    Please, charts showing GISS with all known adjustments backed out. Much more effective than just showing or listing the adjustments themselves.

  5. JoeK permalink
    February 6, 2013 6:29 pm

    Matt Ridley has referenced this post with the claim that NASA has made ‘unexplained “adjustments” to old records’. In what sense, if any, are you claiming that these adjustments are ‘unexplained’? In particular, are you claiming that these adjustments are not a result of changes listed on the GISS updates to analysis pages:

    such as the shift from GHCNv2 to GHCNv3?

    It is useful to flag these changes to discuss if they are correct and justified. But in order to have that discussion it would be useful to clarify if we know where they come from.

    • February 6, 2013 7:11 pm


      Certainly some of the changes have arisen from GHCN changes, but that does not mean they are “explained”. Even GHCN themselves cannot explain the adjustments they have made, and I keep asking them!

      My main beef though is that,as far as I know, GISS never actually publish the revisions, i.e the actual amounts altered, and never keep the old figures archived.

      • JoeK permalink
        February 6, 2013 7:40 pm

        I agree that GISS could, and should, archive each change on the web. But if you are after old figures the wayback machine has 561 captures since 2005:*/

        Looking at the GHCN site they claim to have the unadjusted and adjusted files available for download. You have been asking them for the code that makes this adjustment, and the justification for it?

        So far as the GISS adjustments go, my understanding is that the code has been made available (and rewritten in python), so we can at least see everything that GISS does with the data – or is this wrong?

        If it’s the case that we see the numbers that GISS starts with, what is does with them, and what numbers come out and that process seems consistent then I would say that the adjustments may be wrong or unjustified but I would be careful using the word unexplained (not that you did), as it might give the impression that they are doing something they have not stated. We would have no evidence for that.

      • February 6, 2013 9:01 pm

        I have specifically asked Bryant Korzeníeswki of GHCN to explain how they arrive at the adjustments for Stykkisholmur in Iceland.

        In October he replied

        ” Additionally, they’ll check further into your inquiry re: stations and the actual calculations used in GHCN-M v.3.2 to homogenize the temperature for POR: 1881-1964 at Stykkisholmur, Iceland (Station number 620040130000). Please stay tuned for their further advisement.”

        To date, no answer.(Despite several reminders, and repromises!)

        If they cannot explain them, they cannot justify them.

        I have also asked Reto Reudy of GISS to explain how the UHI adj at Reykjavik manages to increase the warming trend, despite no station changes. His answer – “No I can’t”.

        GISS/GHCN can put up as many “updates”/”algorithms”/”somebody spilt coffee on my computer” as they want, but if they cannot answer simple questions, their new figures are neither explained or justified.

        I guess what I am saying is – if you change your numbers, it is up to you to justify such changes beyond reasonable doubt, rather than expect someone else to prove you have done something wrong.

  6. miked1947 permalink
    March 24, 2013 7:31 pm

    This is the best explanation I have found:
    It is not real temperature data but model outputs based on input WAG and proves the theory GIGO!

  7. March 25, 2013 6:18 pm

    Reblogged this on Climate Ponderings.


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