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1981 Paper's Predictions for Global Temperatures Spot-On

Posted by Unknown on from the we're-all-gonna-die dept.

Layzej writes "The Register reports on a paper published in Science in 1981 projecting global mean temperatures up to the year 2100. 'When the 1981 paper was written, temperatures in the northern hemispheres were declining, and global mean temperatures were below their 1940 levels. Despite those facts, the paper's authors confidently predicted a rise in temperature due to increasing CO2 emissions.' The prediction turns out to be remarkably accurate — even a bit optimistic. The article concludes that the 1981 paper is 'a nice example of a statement based on theory that could be falsified and up to now has withstood the test.'"

24 of 371 comments (clear)

  1. monkeys throwing darts... by Anonymous Coward · · Score: 4, Insightful

    I'm not commenting on the climate one way or the other, but when you have dozens of different predictions over the years is it really surprising that a couple of them happened to hit the mark? Don't forget the Global Cooling sentiment which was around just a couple of years before this article came out...

    1. Re:monkeys throwing darts... by jIyajbe · · Score: 5, Insightful

      No, because the multiple predictions are not random, the way thrown darts are. This is Science 101. Multiple models are proposed to explain and/or predict an observable phenomenon. The model that makes the the most accurate predictions gains credence over the others.

      --
      "Don't blame the log for the fire." --Andrew Ratshin
    2. Re:monkeys throwing darts... by Anonymous Coward · · Score: 3, Insightful

      Oh not this horseshit again. There was never a "Global Cooling" frenzy.

    3. Re:monkeys throwing darts... by Anonymous Coward · · Score: 3, Insightful

      It's cherry-picked info. (I'm not saying Climate Change is not happening, just saying this is not science). I'm not sure what part of this data is falsifiable. It doesn't have any kind of error analysis and some of the assumptions are known to be false or be different than expected. You can't simply say, "It will get warmer", be off by as much as 30% and get credit for good science. This is the kind of thing that drives me nuts. Climate change *could* be a serious thing but it gets washed up with politically driven junk from activists. They are doing more harm than good.

    4. Re:monkeys throwing darts... by Elbereth · · Score: 5, Insightful

      There's a difference between a scientific theory that ends up correctly modeling reality for a long period of time and me just making wild guesses. However, a lot of people will conflate the two, saying that all those scientists were doing was making wild guesses that happened to pan out. This is the same kind of thing that creationists say, when they point out that evolution is "just a theory". It also allows them to create their own competing "theory", consisting of a bunch of mythological stories.

      Science is not just a bunch of old guys with wild hair who sit around, pulling shit out of their ass, and saying, "Hey, this sounds good. Let's go with this wild guess. The public will eat it up, and we'll get more grant money!"

    5. Re:monkeys throwing darts... by Lumpy · · Score: 1, Insightful

      "Oh not this horseshit again. There was never a "Global Cooling" frenzy."

      Wanna bet? I guarantee there was one before the last mini ice age we had.

      --
      Do not look at laser with remaining good eye.
    6. Re:monkeys throwing darts... by houstonbofh · · Score: 3, Insightful

      Seriously though, has it never occurred to you that there are huge disinformation campaigns out there funded by biased parties?

      Yep. On both sides. This is why both sides have zero credibility with the other. Both sides call the others lying bastards, and for a vocal minority on both sides, they are right.

    7. Re:monkeys throwing darts... by houstonbofh · · Score: 3, Insightful

      Science is not just a bunch of old guys with wild hair who sit around, pulling shit out of their ass, and saying, "Hey, this sounds good. Let's go with this wild guess. The public will eat it up, and we'll get more grant money!"

      Actually, it does include people like that too... And unfortunately, those guys are most likely to get the press. For the record, "Peer Reviewed" is not USA Today.

    8. Re:monkeys throwing darts... by Anonymous Coward · · Score: 5, Insightful

      Exactly why the "controversy" is political and not scientific.

      If the arguments were scientific, the conclusions would not be divided among party lines - yet they are. That should tell you something.

    9. Re:monkeys throwing darts... by niftydude · · Score: 3, Insightful

      Only if they consistently make accurate predictions, and not just hit the Loto once.

      Unfortunately, for this particular research area, we only have one planet to experiment on. So they can't exactly reset the planet back to 1981, change the amount of CO2 in the atmosphere, and re-run the experiment to see what the difference is.

      Besides, they didn't just randomly draw a curve on a piece of paper, they designed a mathematical model, fed data into it, and made predictions based on that.

      --
      You can never know everything, and part of what you do know will always be wrong. Perhaps even the most important part.
    10. Re:monkeys throwing darts... by qmaqdk · · Score: 2, Insightful

      Yep. On both sides. This is why both sides have zero credibility with the other. Both sides call the others lying bastards, and for a vocal minority on both sides, they are right.

      I'm curious. Who do you think is funding the side that's supported by 90% of climate scientists worldwide?

      --
      My UID is prime. Hah!
    11. Re:monkeys throwing darts... by nedlohs · · Score: 5, Insightful

      No it gained credence over other models that didn't get things right.

      That in itself says nothing about whether it is actually correct in itself just whether it makes good predictions. A simpler model that makes exactly the same predictions would be prefered - that's what Occam's razor actually says after all. If the models make different predictions we don't need the razor we just see which one (if any) matches reality.

    12. Re:monkeys throwing darts... by Gadget_Guy · · Score: 5, Insightful

      I see no evidence that you even read this paper. All you are doing it spouting the standard denialist memes: it's cherry picked; it's not science; it's not falsifiable, etc. You say there is no error analysis, but does that mean that they gave a single temperature prediction? No, even just looking at the graph in the article you can see there is quite a wide range to their prediction with different areas based on what the human response to this problem was.

      You say some of the assumptions are false? Which ones? Why did you not include even a single example of how they got it wrong? And here is the my biggest problem:

      You can't simply say, "It will get warmer", be off by as much as 30% and get credit for good science.

      I did a search in the article for the text "It will get warmer" and could not find a match. It seems that the scientists behind the paper agreed with you, and so they didn't just make a single proclaimation without showing any supporting evidence.

      Climate change *could* be a serious thing but it gets washed up with politically driven junk from activists. They are doing more harm than good.

      Surely it is the skeptics that are doing the most harm. You know the ones. They have claimed over the past decade that global warming is false because it is actually getting cooler (although they have had to change this to claim that the temperature has remained steady once it became obvious that it was not getting cooler). They are the ones who make claims about climate changes without providing any supporting evidence, but will also deride scientists (who do actually show their working and their data) as doing the same.

    13. Re:monkeys throwing darts... by Anonymous Coward · · Score: 2, Insightful

      Don't get me wrong, I'm not saying there's no scientific consensus. I'm saying there's no scientific controversy (not significant controversy, anyway).

      The whole topic only became politicized when liberal lawmakers called attention to it, and there was a conservative backlash of "skepticism" aimed to discredit AGW. Almost nobody in the political arena was actually investigating the science seriously.

      Strangely enough, the scientific conclusions have not changed much if at all since the controversy erupted. While the partisans and the press and the talking heads "debate" the issue, the climate scientists have just gone about their work (with no small distraction), confirming one hypothesis after another. That would hardly be the case if it were just money driving the studies.

    14. Re:monkeys throwing darts... by ilguido · · Score: 2, Insightful

      Model A: Acceleration due to Earth's gravity near the ground in a vacuum is ~10 m/s^2, so the ball should fall 100 meters in 4 seconds. Model B: Acceleration due to Earth's gravity near the ground in a vacuum is ~5 m/s^2, so the ball should fall 100 meters in ~5.8 seconds. Time for a ball to fall 100 is slightly over 4 seconds. Ergo, 10 m/s^2 is less wrong than 5 m/s^2.

      In the words of Isaac Asimov, Model A is wrong, Model B is wrong, but if you think that Model A is as wrong as Model B, then your view is wronger than both of them put together.

      This example is clueless: the OP wasn't questioning the identificated parameters of the model, but the model: in your example both models are the same!

      To show you how wrong your example is:
      Model A: acceleration due to Earth's gravity near the ground in a vacuum is 9 m/s^2, so according to A a 0.5 kilos ball should fall 1000 meters in ~14.9 seconds.
      Model B: acceleration due to Earth's gravity near the ground in a vacuum is (4 + weight/0.086) m/s^2, so according to B a 0.5 kilos ball should fall 1000 meters in ~14.28 seconds.
      Model B is completely wrong, while Model A is pretty accurate, however for a 0.5 kilos ball Model B gives better predictions.

    15. Re:monkeys throwing darts... by RightSaidFred99 · · Score: 5, Insightful

      I'm not a denier, but you're not really countering his point. If 500 scientists make 500 predictions, and one is right but 499 are wrong you can't really point to that one (possibly lucky) guy and say "see, we knew it!".

      What if I come up with some new crackpot theory tying the price of tea in china to the average incidence of Herpes amongst 19-22 year olds and then predict the price in 5 years based on that theory. I then get lucky, and the price matches my prediction. Have I totally kicked ass with my new theory of Herpes-driven tea prices?

      Like I said, I do believe in man-made GW, but the "other side" can easily find one loon who happened to be right and point to him as proving their point. We need broader theory and broader, more often repeatable tests.

    16. Re:monkeys throwing darts... by bunratty · · Score: 3, Insightful

      Exactly. Then they see which models gave the worst predictions and throw them out. That's how models get better over time. This is precisely how science works. You understand!

      --
      What a fool believes, he sees, no wise man has the power to reason away.
    17. Re:monkeys throwing darts... by Mindcontrolled · · Score: 1, Insightful

      So, where are those 499 wrong predictions? Ah, right, they do not exist. Consensus and all that.

      --
      Ubi solitudinem faciunt, pacem appellant.
    18. Re:monkeys throwing darts... by b4dc0d3r · · Score: 4, Insightful

      You mean the way Einstein predicted things that "fit after the fact"? Just last year we found at least one more of his predictions was true. He's just like Nostradamus, right?

      A model gets proposed, then tested. The ones that are closest to reality are proven correct, the ones that don't are proven incorrect. You are saying that this person's credibility is strained because a lot of other people were wrong? If that is how we measure credibility, then how is anyone supposed to be credible?

      http://www.nytimes.com/2011/05/05/science/space/05gravity.html?_r=1&partner=rss&emc=rss

      There was a 2007 story about this, but from what I can tell the experiment didn't conclude until 2011.

    19. Re:monkeys throwing darts... by dkleinsc · · Score: 3, Insightful

      In my example, both models had acceleration due to gravity as a constant, determined to be that way from previous experiment or theory, and so the question was what that constant actually was.

      And of course, Model B goes to pot as soon as you change the parameters of the test, dropping the ball 100 meters instead of 1000 meters, dropping a ball weighing something other than 0.5 kilos, etc. In the case of climate science, the model not only has to predict where things are now, it obviously has to predict many data points in between 1981 and now.

      Alternately, and this seems to be the standard demanded by those who disagree that climate change is real, we could build a second planet Earth, place it in a clone of our solar system, and then try different levels of carbon emissions to see what happens. The obvious objection here is that such an experiment could not be carried out.

      --
      I am officially gone from /. Long live http://www.soylentnews.com/
  2. 30% off is spot-on by HBI · · Score: 3, Insightful

    Tells you about the rigor of climate science, that's for certain.

    --
    HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
    1. Re:30% off is spot-on by Trepidity · · Score: 4, Insightful

      I'm going to make a wild guess that you don't know very much about science in any field.

      --
      10 PRINT CHR$(205.5+RND(1)); : GOTO 10
    2. Re:30% off is spot-on by rrohbeck · · Score: 4, Insightful

      Yeah, warming is 30% higher than they predicted, they were clearly wrong.

      --
      thegodmovie.com - watch it
  3. Re:Predictions that come true... by Anonymous Coward · · Score: 2, Insightful

    Noting that the real world observations *didn't* match Hansen's predictions (they were higher than expected at first, and then plateaued), what can we conclude?

    1) Oh noes! It's worse than we thought!
    2) The model, including its central conceit, is wrong. Back to the drawing board.

    Or:

    3) Hansen's climate model was right but his emissions projections were wrong.

    4) The model was "wrong", in the sense of having a climate sensitivity different from the real world, which is unsurprising because climate sensitivity was uncertain by about a factor of 50% before Hansen's paper. This observation cannot "invalidate the central conceit" (i.e., falsify the greenhouse effect) if it's consistent with the expected error bars.

    5) You're an idiot, given all your moronic blathering in this threads about how modern climate change is indistinguishable from natural variation. That might be true if we had no observations of the sources of natural variation. But observations of cosmic rays and solar activity exclude a solar cause of the recent warming, observations of ocean heat uptake exclude an oceanic cause, etc. Saying "it's just an expected recovery from the Little Ice Age" is profoundly stupid, when you ignore what factors caused the LIA and its recovery, and whether they are acting today in the same way.