From Skeptical Science:


35 responses to “

  1. He forgot to include the effect of the decline in solar luminosity.

  2. Yup, solar’s there. I’ve mostly followed Tamino’s approach (and the method is entirely inspired by and builds on his work), but I’ve made some different (arguably more conservative) assumptions. Instead of allowing the volcanic and solar terms to vary separately, I’ve used the forcing values in W/m2 and added them before fitting. This reduces the number of parameters by two. The result is a larger volcanic and smaller solar effect, which is why my adjusted trend is a bit lower than that in F&R.
    I also changed the way the lag is handled – for complex reasons revealed in a paper by Rypdal these two changes have to be made together to get a sensible result.
    Finally, I’ve done some validation tests, which aren’t shown in the video. There are more details in the advanced rebuttal at SkS, but I need to write up the whole thing properly when I have time.

    • Kevin – how did you quantify exactly how much effect the ENSO oscillation has?

      • The same way Tamino does – by fitting the solar+volcanic, enso, and trend to the observed temperatures and using the weights which give the best fit.
        I did a few additional checks though – I tried allowing a change in trend at 1997, I tried just fitting on pre 1997, and I did the a calculation with a 2-box + enso model on the whole 133 year record. In every case you get essentially the same result. The size of the enso signal is extremely well determined by the data. IIRC the t-value is in excess of 20 for the 133 year calc.

  3. Such a simple explanation, well done.

    • Simple is beautiful (no stupid about it).

      Thank you Tamino, Kevin C. and SkS.

      I wonder when we will see this posted as a topic for discussion over at Mr. Watts’ place.

  4. Very succinct – this belongs with the Escalator as a ready visual reference.

    I do wonder if it’s worth trying to shift the focus from surface air temperatures to some measure of overall global heat content? Of all the measures and indicators of what’s happening it seems like global air temperatures have a lot of year to year and decade to decade variability, yet still gets treated as the definitive measure of how much our world is warming. Despite the historical reach of temperature records and air temperatures being what humans most directly experience I think it may not be the best ‘definitive’ measure of change.

    • David B. Benson

      Unfortunately there is insufficient knowledge of ocean heat content on a less than centennial scale.

      We have to ‘muddle through’ with the system identification problem, with insufficiently long instrumental records.

      • David, not even for the modern warming period – say the past 30 to 40 years? And from now into the future?

        Surface temperatures surely remain a secondary (or tertiary?) impact of that rising heat content and heat content seems to be a more fundamental measure of global warming.

      • David B. Benson

        Ken Fabian — My understanding is that Terra’s energy budget doesn’t close. Despite talk of putting a satellite out at L1, many climatologists don’t see much point because there are other ways of actually determining TOA temperatures (and hence heat flux). So the assumption is the extra heat is going into the deep ocean. But AFAIK there is no way to directly measure that.

      • David and Ken,
        Actually, you can learn quite a bit by looking at TOA spectrum. Whether DSCOVR is the right tool for this is another question–and yes you learn much, much more if you have another bird over the night side. There’s a lot of good science that can be done. Unfortunately, DSCOVR was always a low-budget enterprise–a legacy of Faster, Cheaper, Better (pick ahy two!). So who knows how effective it will be?

      • I suppose I’m trying for a measure that is more readily comprehended, that gets to the heart of the climate problem, that doesn’t show the kind of variation that is so amenable to misinterpretation. Energy in and energy out at TOA is certainly at the heart of the climate problem but I’m not so sure it’s readily comprehensible in the way heat content would be.

        But if heat content isn’t based sufficiently on direct measurement or reliable proxies then we are probably stuck with surface air temperatures. Tamino has done a lot for clearer interpretation of global temperatures by bringing to light the known natural drivers of variation in a comprehensible way – which has led to the image at the top of this page – but it’s variability will remain an opportunity for misunderstanding and misinterpretation that the opponents of action on climate will continue to exploit.

      • Ken, unfortunately there is no metric which is immune to deliberate obfuscation, misinterpretation, misunderstanding or distortion.

      • Kevin, that’s true, however I suggest it would be harder to get people to believe the greenhouse effect comes and goes and has stopped or slowed recently when the preferred or ‘definitive’ metric is something like this –

        Most of all our community leaders and elected representatives need to be persuaded as the wider legitimacy of denial is greatly impacted by those ‘respected’ and ‘credible’ and influential voices. They ought not be treated as simpletons who would mistake the downs of the ups and downs of global surface temperatures for global warming stopping – but it’s painfully apparent arguments like that, if not believed, are treated as a good rhetorical argument for the choices they prefer to make. They would find that justification harder with a metric that sees little year to year or decadal variation.

  5. I wonder how many of the past 16 or 60 years would show a statistically significant increase in world temperatures if one was to cherry pick the year of lowest temperature as the baseline?

  6. Is the temperature record monthly data with some kind of smoothing applied?

    • Yes, the whole calculation is done on monthly data. A 12 month moving average is applied for the graphics only.
      (For more details go to and click on ‘Advanced’)

  7. 6118… ?

    I’ll bite – You mean something like on another galaxy similar to our own?

  8. Theo van den Berg

    Beautiful simple animated graph and there are more on that very well presented site. Isn’t it a pitty that we have to waste so many precious resources fighting these Skeptics. And our methods of peacefull resistance, provide great entertainment, but they obviously DO NOT WORK. Science could probably provide a link between these Skeptics and the real physical death (read murder) of my grand children. Isn’t it time for revenge and make a list of the greatest villans and knock off the top 10 contributers ? [edit]

    [Response: Let me be very clear: I do not advocate violence. I advocate against it. I find even the suggestion offensive, and it hurts our cause tremendously. You don’t help the situation by threats — not even when in jest.

    The only reason I allowed this comment is to make it clear how strongly I disagree. No more of this.]

    • Yeah. Its pretty easy to see how repulsive such ideas are when the fake skeptics draw up their hit lists. We don’t need to stoop that low.

    • The only weapon we have is the truth, and it is true that it is a weapon that acts slowly sometimes. However, it is not a weapon I have known to fail ultimately–and that makes it powerful. Any other weapon or strategy we seek to add will ultimately dilute the efficacy of truth and slow our progress. We cannot afford this. Stick to truth. The rest will follow.

      Or as Mark Twain said: “If you tell the truth, you’ll eventually be found out.”

    • “And our methods of peacefull resistance, provide great entertainment, but they obviously DO NOT WORK.”

      I am not so sure about that. My sense is that things started shifting last year with regard to public perception. The deniers are now “on the run” and their credibility is taking a hit. This is due to the efforts of folks like Tamino, SKS, the Climate Science Rapid Response Team, and “The Conversation.” Debunking the deniers’ nonsense promptly is proving to be effective.
      We obviously still have a long way to go in terms of getting political action.

    • I’d have to to say the the Denialists of the world would just love to see violent tactics deployed against them. Self-justification through a persecution complex is a big part of their thinking, and of course actually being persecuted would reinforce this.

      The fact that we live in a world where the slightest misstatement of outburst from a climate scientists is shouted from every street corner, whereas denialists can issue death threats with apparent impunity, should serve as a warning.

      Personally, I’d consider some sort of ‘Truth Libel’ law – in which a person who repeatedly, publically and knowingly lied about a subject (and that lie would lead to physical harm) could be put on trial.. think tobacco and cancer. Call it the ‘SpaceShip Earth Protection Law’ – since if you lived on a long-trip spaceship, lying about the status of supplies or environmental controls would indeed by a very serious offence.

      But it would be an enormously hard law to craft – after all it would outlaw a fair chunk of the body politic – and extremely dangerous in the case of ideologues getting hold of the levers of power. Imagine being a sane person when Fox News was declared the ultimate arbiter of truth by the courts.

      So.. physical attacks would be massively counter productive (and morally wrong!). Legal attacks would probably fail and in any case have a strong chance of backfiring – free speech defenses I find overly simplistic, though. The only thing that can be done is to repeatedly state reality; Nature will gradually convince.. and start looking at REALISTIC plans for what a zero-carbon energy economy would look like.

  9. Thank you, Tamino. I am in complete agreement.

    Case in point: the Heartland ‘psychopath’ billboards. (A huge ‘own goal’ for them.)

  10. I agree wholeheartedly with Tamino, Kevin and John. It is incredibly frustrating when every day is Groundhog Day, again, but there’s no excuse for stooping to that level. Let’s continue to rely on science.

  11. Horatio Algeranon

    “Sixteen Flat-years”

    — Horatio Algeranon’s rendition of “Sixteen Candles”
    (Luther Dixon and Allyson Khent)

    Sixteen flat-years
    Make a lovely claim
    But not as lovely, as the cycle game
    (As the cycle game, oh)
    Trend on the flat-years
    Make your wish come true
    For I’ll be wishing for La Niña, too
    (For La Niña, too)
    It’s only sixteen (sixteen)
    But it’s my “no-warm” dream
    (It’s my dream)
    It’s the prettiest
    Loveliest flat-line I’ve ever seen
    (I’ve ever seen, oh)
    Sixteen flat-years in Heartland will glow
    For ever and ever for I love them so
    (For I love them so)
    It’s only sixteen (sixteen)
    But it’s my “no-warm” dream
    (It’s my dream)
    It’s the prettiest
    Loveliest flat-trend I’ve ever seen
    (I’ve ever seen, oh)
    Sixteen flat-years in Heartland will glow
    For ever and ever for I love them so
    (For I love them so)
    For I love them so

  12. I enjoy your blog, and have nominated you for a Very Inspiring Blogger Award. The details are at

  13. I should update my blogroll. But that is a very clear representation. Must have taken quite a bit to make, or is there some editing software that would do that accurately?

  14. I coded the whole animation in python. (R can do similar but the base graph package wasn’t as good at filled regions). Each transition is ~12 lines of code, but most are cut and pasted. The script and then synchronization to the voiceover took as long as the video. I guess it took ~2hours/night for 2 weeks over Christmas.