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The legend of the Titanic

Filed under: — rasmus @ 3 May 2012

It’s 100 years since the Titanic sank in the North Atlantic, and it’s still remembered today. It was one of those landmark events that make a deep impression on people. It also fits a pattern of how we respond to different conditions, according to a recent book about the impact of environmental science on the society (Gudmund Hernes Hot Topic – Cold Comfort): major events are the stimulus and the change of mind is the response.

Hernes suggests that one of those turning moments that made us realize our true position in the universe was when we for the first time saw our own planet from space.

NASA Earth rise

He observes that

[t]he change in mindset has not so much been the result of meticulous information dissemination, scientific discourse and everyday reasoning as driven by occurrences that in a striking way has disclosed what was not previously realized or only obscurely seen.

Does he make a valid point? If the scientific information looks anything like the situation in a funny animation made by Alister Doyle (Dummiez: climate change and electric cars), then it is understandable.

Moreover, he is not the only person arguing that our minds are steered by big events – the importance of big events was even acknowledged in the fiction ‘State of Fear‘.

A recent paper by Brulle et al (2012) also suggests that the provision of information has less impact than what opinion leaders (top politicians) say.

However, if the notion that information makes little impact is correct, one may wonder what the point would be in having a debate about climate change, and why certain organisations would put so much efforts into denial, as described in books such as Heat is on, Climate Cover-up, Republican war on science, Merchants of doubt, and The Hockeystick and Climate Wars. Why then, would there be such things as ‘the Heartland Institute’, ‘NIPCC’, climateaudit, WUWT, climatedepot, and FoS, if they had no effect? And indeed, the IPCC reports and the reports from the National Academy of Sciences? One could even ask whether the effort that we have put into RealClimate has been in vain.

Then again, could the analysis presented in Brulle et al. be misguided because the covariates used in their study did not provide a sufficiently good representation of important factors? Or could the results be contaminated by disinformation campaigns?

Their results and Hernes assertion may furthermore suggest that there are different rules for different groups of people: What works for scientists doesn’t work for lay people. It is clear from the IPCC and international scientific academies that climate scientists in general are impressed by the increasing information (Oreskes, 2004).

Hernes does, however, acknowledge that a background knowledge is present and may play a role in interpreting events, which means that most of us no longer blame the gods for calamities (in the time before the enlightenment, there were witch hunts and sacrifices to the gods). The presence of the knowledge now provides a rational background, which sometimes seems to be taken for granted.

Maybe it should be no surprise that the situation is as described by Hernes and Brulle et al., because historically science communication hasn’t really been appreciated by the science community (according to ‘Don’t be such a scientist‘) and has not been enthusiastically embraced by the media. There is a barrier to information flow, and Somerville and Hassol (2011) observe that a rational voice of scientists is sorely needed.

The rationale of Hernes’ argument, however, is that swaying people does not only concern rational and intellectual ideas, but also an emotional dimension. The mindset influences a person’s identity and character, and is bundeled together with their social network. Hence, people who change their views on the world, may also distance themselves from some friends and connect with new people. A new standpoint will involve a change in their social connections in addition to a change in rational views. Events, such as the Titanic, Earth rise, 911, and Hurricane Katrina influence many people both through rational thought and emotions, where people’s frame of mind shifts together with their friends’.

What do I think? Public opinion is changed not by big events as such, but by the public interpretation of those events. Whether a major event like hurricane Katrina or the Moscow heat wave changes attitudes towards climate change is determined by people’s interpretation of this event, and whether they draw a connection to climate change – though not necessarily directly. I see this as a major reason why organisations such as the Heartland are fighting their PR battle by claiming that such events are all natural and have nothing to do with emissions.

The similarity between these organisations and the Titanic legend is that there was a widespread misconception that it could not sink (and hence its fame) and now organisations like the Heartland make dismissive claims about any connection between big events and climate change. However, new and emerging science is suggesting that there may indeed be some connections between global warming and heat waves and between trends in mean precipitation and more extreme rainfall.


  1. R.J. Brulle, J. Carmichael, and J.C. Jenkins, "Shifting public opinion on climate change: an empirical assessment of factors influencing concern over climate change in the U.S., 2002–2010", Climatic Change, vol. 114, pp. 169-188, 2012.
  2. N. Oreskes, "BEYOND THE IVORY TOWER: The Scientific Consensus on Climate Change", Science, vol. 306, pp. 1686-1686, 2004.
  3. R.C.J. Somerville, and S.J. Hassol, "Communicating the science of climate change", Physics Today, vol. 64, pp. 48, 2011.

169 Responses to “The legend of the Titanic”

  1. 101
    t marvell says:

    Havers 99 Ladbury 86 and others. What would you do? You seem to be saying there is no chance of persuading people to act on AGW, so there is no sense in trying, so the world is doomed to fry.
    I think the climate scientists must try. I pay taxes; I have grandchildren. From my point of view, the climate scientists cannot simply follow their own scientific desires, without practical and active concern to what they know will happen to us all.

    Christian (83) and many other similar comments – As Griffiths (98) points out, the long term trend is upward. For a while in the 80′s and 90′s temperature growth was greater than the trend, and greater than was expected. The leveling off in this century brings trends back to normal.

    Christian and the others illustrate a problem. People often look at the most immediate information. It might help if climate scientists can concentrate more on perfecting relatively short term temperature preduction, say a decade out. That obviously would not be enough alone to counteract the deniers, but many things of that nature, that people can easily understand, might be sufficient.

  2. 102
    Fred Emmer says:

    #88 , thanks for the great graph with no description on either axis.

    To send this to a person who said he is a layman on the issue, is exactly whats wrong with the way the agw community communicates with uneducated (on this subject) skeptics. Its like saying , trust us, we’re experts, but if you want proof here’s a picture of an ascending line.

  3. 103
    flxible says:

    t marvell – Why do you think it’s the job of climatologists to “persuade people“? It’s your job to persuade your politicians to pay attention to science, from most polls I see the general populace appears to be persuaded, but are not being offered any alternatives by the powers that be.

  4. 104

    @ Fred Emmer

    No need to get snippy. dhogaza’s graphic may be a bit Prose-deficient, but all the info required is there. Since the original challenge was that there was “no warming since 2000“, how about a graphical depiction of temperature changes (anomalies) since 2000? From GISS:

    Note that the majority of the globe, by far, has warmed since 2000. Here’s the temperature changes, by latitude (also from GISS):

    Yup. Warming. Still.

  5. 105

    #102–Christian may be a layman, but I suspect he won’t have any great difficulty making the inference that one axis is years–”2000_2002_2004…2012″ is pretty suggestive–and the other is temperature anomalies in tenths of a degree (since the topic under discussion was, after all, warming.)

    Note, if you are not familiar with it, that “Woodfortrees” is an interactive site. Highly recommended for all with active senses of curiosity.

  6. 106
    Bob Loblaw says:


    Well, when I click on dhogaza’s link (in #88), I see a graph with years on the horizontal axis labelled in something most people would probably guess is years, and a legend that explains we’re looking at HADCRUT4. Don’t know what that is? The web page also has a series of links at the top, one of which is labelled “About”. On that page, the upper right corner has “HADCRUT4″ mentioned in big letters. There is a lot of other stuff on that “About” page, and I’m sure there are details to be found somewhere there. In response to a person who claimed it isn’t warming, is it difficult to figure out this is temperature?

    Just how “uneducated (on this subject)” are the “skeptics”???? Or is this a case of “you can lead a horse to water, but you can’t make him drink”?

  7. 107
    dhogaza says:

    Fred Emmer:

    #88 , thanks for the great graph with no description on either axis.

    How funny, the forms on the right say “from *(time) 2000″, and since the claim is that there’s no warming since 2000, one would expect that *even you!* would understand that “from (time) 2000″ is semantically equivalent to “since 2000″.

    Would you care to make a case for ambiguity in understanding that the two phrases are equivalent?\

    And, of course, the site has ample documentation explaining that the X axis with numbers like 200* are years, etc.

    If you can’t navigate the site and find its clear explanations, then you’re rather hopeless, I’m afraid.

  8. 108
    Radge Havers says:

    t marvell @ 101

    “What would you do?”

    Well what are you going to do? I mean you could, for instance, go to the source of the problem, camp out on politicians’ websites and relentlessly badger them about why they’re circling the wagons around inaction on climate change. Surely your software can handle that.

  9. 109
    dhogaza says:

    Fred Emmer:

    To send this to a person who said he is a layman on the issue, is exactly whats wrong with the way the agw community communicates…

    Actually, I’d say that a layman skeptic who claims it hasn’t warmed since 2000 is exactly what’s wrong with how the skeptic community communicates – it’s a lie. Suggesting that pointing out that it’s a lie with a clearly understandable graphic is somehow a problem with how the reality-based community communicates reality is just bizarre.

    I wasn’t even rude. I just pointed to the data and said “you’re wrong”. He was wrong. End of story.

  10. 110
    t marvell says:

    Havers 108, flexible 103. I’m not sure what to do. I see a big wreck coming up because there seems to be nothing on the horizon to slow down global warming. If one spends the time to look closely (or if one is politically liberal) one sees that the climate scientists have shown the dangers of AGW. But that has gotten us almost nowhere in the policy arena. As a citizen, I feel like: “the climate scientists have done their job, and now we don’t need them anymore.” – that is, unless they can do something further to prompt the world to limit AGW.

    As for specific things, I can only guess. The problem, as I see it, is that people and politicians, even if they generally agree with AGW, don’t feel strongly enough to take action, especially in the face of the energy interests. In earlier comments I have written about specific things that might be done. For the moment, I think the climate scientists must start thinking in this vane. What information can they provide that might prompt people to action?

  11. 111
    Dan H. says:

    To graph viewers,
    I think people are getting a bit snippy on the graph. Do not blame dhogaza, as that is the way Woodfortrees presents its graph. Those of us who are familiar with this know. Anyway, t marvel has a good point in #101; when temperatures were rising rapidly in the 80s and 90s, support among the populace for agw was easier to gain. Now that temperatures have fallen in line with the longer term rate, the impetus for action has declined. Most of the populous does not pay attention to the causes (La Nina, solar minimum, chineses aerosols, etc.) for the “warming hiatus.”

  12. 112

    “temperatures have fallen in line with the longer term rate”

    More dissembling from Dan H.

  13. 113
    Jim Larsen says:

    110 t marvel said, “As a citizen, I feel like: “the climate scientists have done their job, and now we don’t need them anymore.””

    Appropriate policy would be quite different with a climate sensitivity of 2C/doubling than with a sensitivity of 4.5C. Incidentally, if I were a skeptic, I’d start espousing the virtues of the bottom of the consensus range. That’s quite the compromise compared to Iris Effect estimates. Fair and balanced, you might say, and even at 550 ppm CO2, temperatures stay below the magical 2 degrees.

    However, your sentiment is valid. If I could snap my fingers and climate science would halt for ten years but all of mankind would estimate sensitivity to be 3C and would understand the implications, then it would be tempting to snap my fingers.

  14. 114
    Fred Emmer says:

    I am a skeptic for when it comes to global warming. But I could be wrong, and I am totally willing to listen to those who think I am wrong. I work in law enforcement, and I do have a b.s degree (in unrelated field).

    The reason I doubt agw, is because I have lost trust in the scientists involved in climate science. I do not like the way they have dealt with the mistakes they have made.

    Of course I understand 2000-2012 represents years. But the spikes and the scale on the y-axis, raised a red flag for me. I know the graph is auto-scaled and not made with the intention to deceive. When I post this concern, I thought someone would say “hey it means the difference in temp between what was measured and what we expected it to be”.
    Instead commenters say : “said “you’re wrong”. He was wrong. End of story” (#109). Or “…then you’re rather hopeless” (#107).

    Or “is it difficult to figure out this is temperature?”.

    #107 Just how “uneducated (on this subject)” are the “skeptics”? – I am very uneducated on climate science, I can not prove that it is not happening. There are scientists on both sides of the story, and I get to choose which one to believe. I believe there is a consensus among those who chose to study climate science.

    Now I still dont know what the graph means, what I do know is, that while there was no lack of people pointing out my simplicity in not guessing what it meant, there was not a single person who said “it means this or that”. It proves my point that the agw community is not that great at communicating with skeptics.

    If I was being tried in court, I would love to prosecution to show a chart like that to the jury.

  15. 115

    #114–Fred, your original comment did not communicate (to me, at least) that *you* wanted to know what the graph meant. The wording suggested rather that you knew, but were concerned that a generic ‘layman’ might have trouble figuring it out.

    Since it seems you are asking, let me lay it out for you.

    The vertical axis is the new HadCRUT4 product, which consists essentially of a (nearly) global mean anomaly. “Anomaly” means the deviation from the average value for each station over a specified 30-year baseline. There’s a discussion of some of the gory details here:

    As you inferred, the horizontal axis shows time, calibrated in years.

    The red wiggly line is the temperature record. You may not like the ‘spikes’–I’m sure some climate scientists might agree, since understanding the system would presumably be a bit easier if it weren’t so ‘noisy,’ but that’s what the data says–the Earth’s surface temperature fluctuates all the time in response to things like volcanic eruptions, small changes in solar output, and large circulation changes likethe famous ENSO–the El Nino/La Ninas.

    The green line is the linear trend calculated by the standard ‘least squares’ method, and it shows that by that measure, the mean temperature anomaly has gone from .4 C above the baseline value to .5 C–hence it’s a pretty good riposte to the idea that there’s “no warming” since 2000. (It’s true, by the way, that that warming does not reach conventionally-mandated levels of statistical significance–for the temperature record, this typically tends to take around 17 years. But that doesn’t mean that the warming is not ‘real.’)

  16. 116
    Hank Roberts says:

    You got pointed to a chart readable by people who already know what it means. It’s a handy tool but you need to read the FAQs at the site to use it.

    The guy who sent you there was mistaken. He assumed you would know how to use the tool and just showed you one of the results anyone who uses it can get.

    What you wanted (or wanted to show naive readers) is an explanatory graph with labels and explanations suitable for presentation.

    You got pointed to the raw material. That was a bad pointer.

    It’s easy to think people here know more than they do, and hard to be patient with the very simplest questions that get typed in over and over — which are usually answered behind the “Start Here” button, top left corner.

    Do read the “about” pages on the Woodfortrees site, you’ll find it handy.

    Same for “Start Here” — upper left corner.

  17. 117
    Ray Ladbury says:

    Fred Emmer says: “I do not like the way they have dealt with the mistakes they have made.”

    Care to elaborate? Personally, I don’t know of any “mistakes” that cast doubt onto a single important result that underlies the consensus. Do you?

    You say there are scientists on both sides of the “debate”. While true, wouldn’t you expect those who are publishing the most to have the best understanding, and don’t you consider the fact that 97% of them say we are warming the planet remarkable? Are you simillarly doubtful of evolution, the round Earth and the germ theory of disease? After all, there are a few scientists who doubt each of these hypotheses as well.

  18. 118
    SecularAnimist says:

    Fred Emmer wrote: “I have lost trust in the scientists involved in climate science. I do not like the way they have dealt with the mistakes they have made.”

    Which scientists?

    What “mistakes”?

    That “they have dealt with” how?

    And what are your sources of information about these “scientists” and their “mistakes” and how “they have dealt with” them?

    Are you “skeptical” of those sources of information? Do you question what they tell you about “scientists” and their “mistakes”? Or do you believe it unquestioningly?

  19. 119
    dhogaza says:

    Fred Emmer:

    Now I still dont know what the graph means, what I do know is, that while there was no lack of people pointing out my simplicity in not guessing what it meant

    The Wood-for-Trees site is chock full of documentation on what the site does, on what the various graphing options mean, etc etc etc.

    Let’s review the bidding here:

    1. You waltz into a science-based site claiming it’s not warmed since 2000 (something I’m sure you’ve picked up from a denialist site since you’ve made it clear that you’ve not done the research yourself).

    2. I posted a graph showing that, no, actually, that’s a false statement, making the rest of your original comment moot.

    3. You express confusion about the graph, but make absolutely no effort to understand what it means, something you could easily do on your own by reading the documentation on the site.

    4. Now you’re complaining that people don’t communicate to skeptics well. Where’s that vaunted conservative push for taking personal responsibility for one’s [in]actions, such as a failure to RTFM at the site you were pointed to?

    5.”If I was being tried in court, I would love to prosecution to show a chart like that to the jury.” You overestimate yourself and underestimate juries …

  20. 120
    Radge Havers says:

    t marvell @ 110

    Communication is of course important and shouldn’t be downplayed. However, I sometimes like to imagine that there may be some potent combination of words that, if launched at to the appropriate structural weakness, will explode the denialist Death Star once and for all. This is of course just fantasy. The reality is complexity both hard and subtle. That’s life. We keep on keepin’ on.

    There are citizen science projects, advocacy groups you can donate to, news organizations and politicians you can write letters to etc. Perhaps more to your taste, note that Climate Progress sometimes calls on readers to submit slogans, elevator talks, metaphors and that sort of thing, which might go viral. You never know.

    As for scientists, it’s safe to assume that they have well formed ideas of what they need to do. If you’re going to make suggestions, it might be a good idea to canvas their understanding of the situation first.

  21. 121
    Marcus says:

    Mr. Fred Emmer,

    When You explore woodfortrees a little, You will understand that this is an interactive area. The main interest of the programmer is climate data, but one sees clearly that the tool is kept generally for all kind of time series data. You can plot the keeling graph for CO2 concentrations, for instance.
    If the author wanted to have captions on the y axis without loss of generality, he had to maintain additional bookkeeping for units associated with datasets, therefore an associated database table to fill and more code. So seemingly he chose to do not and work with descriptions.
    This is enough for the willing who use it as kind if playground to learn something. And maybe this makes it not a good source to cite for the declared unwilling with preoccupied opinion or to the unlearned. But there is nothing wrong with it.

    All the best,

  22. 122
    Dan H. says:

    The other problem with the graph is the issue of short-term data series. Check out the graphic when the most recent data is included:

  23. 123
    Hank Roberts says:

    Dan H. gave the wrong pointer there.
    I’m sure he intended to point to the Notes page:
    It’s cautionary.
    People will try to fool you.

  24. 124
    Hank Roberts says:

    Remember, any time you link to a Woodfortrees chart, that the site requests:

    “… please link back to these notes so people can understand it and play with it themselves.”

    The link is:

  25. 125

    #122, 123–And, Dan, I’m sure you didn’t mean to gloss over the difference between HadCRUT 3 & HadCRUT 4–did you?

    Let me add GISS to the list–just, you know, for even further context:

    Fred, the truth here is that it’s fairly pointless to look for statistical guidance over 11-year periods with data this noisy. As I said earlier, it usually takes about 17 years for periods to attain statistical significance. There is no evidence that warming has ‘stopped’–something repeatedly claimed by those who *wish* it were true:

  26. 126
    Ferran P Vilar says:

    Here’s an analogy between climate change and the Titanic using systems thinking aiming at popularization: :

  27. 127
    Susan Anderson says:

    Fred Emmer appears to conform to the template of artificial skeptics who come here with an agenda: to prove that science is both wrong and intolerant on this subject. Never mind that many have been remarkably patient, the insistence on the phony “facts” in the face of real evidence, with snippets of snarky commentary, demonstrate that this is not someone curious about what is going on but someone who wants to go home with evidence that this is not a nice playground and to be avoided by real folk.

    I sure do hope I’m wrong, as this is just sad, but not news.

    By the way, this is a gem, I think I got it from another thread, thanks to Ray Ladbury (though it might have been Dhogaza):

    The idea that we should direct research to discover evidence to persuade people who cannot be persuaded by evidence seems rather silly to me.

    In the hope that I am wrong, I would suggest looking out the real temperature record. Try Masters at Wunderground, and world weather news.

    or a host of other locations like ClimateCentral which has this NASA clip that presents the big picture:

    Of course, you’ve already been pointed at SkepticalScience which has scholarly and simple presentations of the facts on almost any subject you’d care to name:

    They address your specific issue with downward trends in a warming world:

  28. 128
    Jim Larsen says:

    125 Kevin asks, “And, Dan, I’m sure you didn’t mean to gloss over the difference between HadCRUT 3 & HadCRUT 4–did you?”

    I wonder when Hadcrut4 will be up to date and why it couldn’t be released that way. Sounds like a story there. In any case, it’s a distraction to have Hadcrut3 keep rearing its obsolete head.

  29. 129
    James Staples says:

    Does, “Seeing the Earth from space for the Very First Time”, Star Leonardo DiCaprio?
    Bummer…..Sorry, I just had to snark at this; but then I swore that, IF I saw even ONE MORE ‘Titanic’ themed ANYTHING, ANYWHERE, that I’d, I’d, I’d……..Arrrrgh!

  30. 130
    Dan H. says:

    As Jim stated, Hadcrut4 is not up to date, so CRUT3 was used to cover the remaining time. This is just nitpicking. Maybe Fred’s question would be better stated as, “how long would temperatures need to show no increase, before scientists reconsider their theory. My answer is 30 years, which when combined with 2000-12 is another 18. In reality, some scientists would rethink the theory long before then.

    Also, the 17 years was gleaned fro the Santer paper, where he determined that 17 years of RSS data was needed to separate a human signal. RSS no longer shows statistically significant warming over the past 17 years.

  31. 131
    Fred Emmer says:

    mr dhogaza,

    I think you have me mistaken for “christian” who dared to claim there had been no warming since 2000. That wasn’t me.

    What I am trying to say is that I believe that the reason more and more people believe climate science is exaggerated is because climate scientists don’t know how to convey their message.

    to #117, I dont think the moderator of the blog will allow me to beat a dead horse.

    Say you were a cop and you arrest a burglar and built a water tight case against him. 1 week you tell the boss your home sick just because it is nice outside. Does that little lie mean you were wrong about the burglary ? No it doesn’t, but you’ll get fired because your boss doesn’t want a defense lawyer asking you when it is okay to lie.
    I hope you understand what I mean.

    mrs Susan, #127 I did not mention any “phony facts” and I did not dispute any of your “real evidence”. Im not sure what I said that made you so upset.

    But on that note, according to that graph, the warming is measured in hundreds of degrees in a period of over a decade. What I was thinking is that judging by the spikes in that graph, all we would need this year is a cold snap and we see a down ward trend.

  32. 132

    #130–”…Hadcrut4 is not up to date, so CRUT3 was used to cover the remaining time. This is just nitpicking.”

    No, in my opinion it is not. HadCRUT 3 has a known low bias, and using it to ‘cover the remaining time’ gives a misleading impression. I know about this bias and so do you.

    “Also, the 17 years was gleaned fro the Santer paper, where he determined that 17 years of RSS data was needed to separate a human signal. RSS no longer shows statistically significant warming over the past 17 years.”

    And your point would be what, exactly? From your own link to the abstract, we can read that “A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal. Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature.”

    Since Santer et al identifies 17 years as the minimal span necessary, it is hardly surprising that not all 17-year spans reach statistical significance. (Oh, and by the way, it’s not just “RSS”–UAH is also considered in Santer et al.–as are a couple of ensembles of model runs.)

    PDF for Santer et al (2010):

    #131–Fred Emmer wrote:

    “But on that note, according to that graph, the warming is measured in hundreds of degrees in a period of over a decade.”

    Huh? No, the warming in the graph is measured in tenths of a degree, as I specifically stated in #105, and discussed in #115–and for that matter, as indicated on the original graph by the presence of decimal points.

    No offense intended, but are you paying attention at all?

  33. 133
    Ray Ladbury says:

    Fred Emmer: “What I am trying to say is that I believe that the reason more and more people believe climate science is exaggerated is because climate scientists don’t know how to convey their message.”

    So facts are not good enough? Would you like us to tell you just-so stories? Or perhaps we could present the conclusions as a sort of modernist dance performance? How about an abstract painting?

    Dude, do you really think how the facts are presented changes them?

  34. 134
    Dan H. says:

    Yes, Santer used UAH also. However, he relied more heavily on RSS for his analysis. His conclusion was that over timescales greater than 17 years, the average trends in RSS and UAH exceeded the unforced control trends. The data used for his paper included temperature values up to Dec., 2010, during which time the 17-year RSS trend was +0.112C/decade. The most recent 17-year trend is +0.035C/decade. In fact, using Santer’s technique, one would have to use the last 19 years of data to find the human effects on global-mean tropospheric temperature. His 17 years was not some magical number which shuold be applied universally, rather, it was the most recent length of time required to show a temperature increase significantly greater than noise.

    Maybe we could alter Christian’s original question to pass Santer’s test; i.e. how many years of data that does not show a human effect on temperatures would be necessary before people alter their thesis. Personally, I feel this is a less stringent test, but it could be meaningful.

  35. 135
    Marcus says:

    Fred Emmer,

    I think the science is communicated very well and in an elaborate way on this very site You are surfing now. Browse the head posts by topic, not just the user comments. Enjoy the abundant ressources of science facts that have not been distorted by some mass media account


  36. 136
    tamino says:

    Lots of people, including those who don’t know much about the subject, come here to learn about the science of global warming. The hosts are good at that. People also want answers to questions, including refutations of fake arguments from fake skeptics. The regular readers are good at that.

    Unfortunately, too many threads devolve into pointless back-and-forth about persistent trash from persistent purveyors trash. They end up being dominated by utter nonsense, like T Marvell’s incompetent treatment of time series data and Dan H.’s misleading portrayals of the science.

    When regular readers pay them any attention at all, it just feeds the trolls.

    When moderators allow this nonsense, it undermines the real purpose of the site. The borehole exists for a reason: comments that would otherwise disrupt sensible conversations. If the comments from T. Marvell and Dan H. don’t disrupt sensible conversations, what the hell does?

  37. 137
    Radge Havers says:

    Fred Emmer

    People need to adjust their expectations about what a presentation can convey about the science. Explanations of the state of the science aimed at lay people are by necessity illustrative. If you want to get into the actual science in any serious way, you pretty much have to learn it the way scientists learn it, which takes years of hard study. You can’t just sit around discussing it and one day magically arrive at the truth. And if you can’t do all the math, all of it, literally, you’re stuck at square one. Ask Ray Ladbury whose comments you’ve read here how long he feels it took him to get up to speed in climate science. And he’s a published physicist working at NASA.

    One of the great disservices septic sites perpetrate on the public is the appealing notion that anybody can just jump in, understand and make meaningful contributions to “the debate”. There’s your scam. Because once roped in by these sites, the unsuspecting are irradiated with crippling doses of lies and misinformation that they’re just not equipped to handle. I have to say that any court that would admit this kind of crap in evidence would be unable to field expert testimony effectively and would be doomed to fail in its duties.

    A good lesson in science in the court room, BTW, was provided in Dover, PA on ID creationism. You don’t have to get deep into the weeds of scientific inquiry to figure out that creationists are full of crap. So too with denialists.

    It is indeed time to put away childish things or we’re going to be in big trouble down the road.

  38. 138

    #134–”More dependent on RSS”–I don’t think so:

    We compare simulated and observed global-scale TLT trends using three different observational datasets, each based on measurements of microwave emissions made by Microwave Sounding Units (MSUs) on polar-orbiting satellites. The three MSU TLT datasets analyzed here were developed by research groups at the University of Alabama at Huntsville (UAH) [Christy et al., 2007] and Remote Sensing Systems in Santa Rosa, California (RSS) [Wentz and Schabel, 1998; Mears and Wentz, 2005].


    And did I say anything indicating that I thought that 17 years was a “Magic number?”

    The whole paper is about probabilities. What you say about the most recent 17 years–or 19, for that matter–is pretty much irrelevant. At the most, trends are on the edge of significance at this point, therefore it is not especially surprising to see the ‘seesawing’ between statistical significance thresholds being met and not being met which you describe.

  39. 139
    Pete Wirfs says:

    Fred said:
    “The reason I doubt agw, is because I have lost trust in the scientists involved in climate science. I do not like the way they have dealt with the mistakes they have made.”

    This is EXACTLY the message that those who wish to maintain status-quo (which is usually motivated by profit) are pushing on the public, and as Fred is proving, it is an effective message to the scientifically un-educated, and further encourages them to IGNORE the actual science, which is where the true story is.

    CUDOs to Fred for (a) having the guts to come here and tell us his true feelings and (b) for being willing to start studying the actual science, which is exactly what the status-quo community does NOT want him to do!

    Science is full of mistakes. Everyone is human. But the denialist crowd would have us believe the court-case analogy My wife is a criminal defense attorney so I know well the point he is making, that in the case of a jury decision you only need to create doubt. But in science you are supposed to note the mistake, learn from it, correct it, and add it to the continually growing pool of knowledge. It is not a jury trial.

    (I’m a novice who has been lurking/learning here for many years)

  40. 140
    Susan Anderson says:

    Marcus@~135 and others (paticularly “skeptics”)

    Thanks for reminding us that the substance of any useful site like RealClimate is in the source material, not in the commentary. RealClimate does provide substance in comments when it is not running around in circles trying to penetrate the miasma created by those who persist in refusing to follow suggestions and pursue resources, but in general the commentariat are just a bunch of individuals like me who like to write and have the time to do so.

  41. 141
    Hank Roberts says:

    > The most recent 17-year trend is +0.035C/decade. In fact, using
    > Santer’s technique, one would have to use the last 19 years of data

    Please. Think about what you’re typing.

  42. 142
    Steve Fish says:

    RE: tamino — 8 May 2012 @ 9:59 AM, currently at #136. I strongly support this statement. Steve

  43. 143
    Jim Larsen says:

    130 Dan H said, “As Jim stated, Hadcrut4 is not up to date, so CRUT3 was used to cover the remaining time. This is just nitpicking.”

    No. You know that CRUT3 is biased low compared to CRUT4. Adding it to the end of a short series of CRUT4 data is _________.

  44. 144
    Jim Eager says:

    Mr Emmer, allow me the opportunity to address your comments as one layman to another, albeit one who has invested much time learning to understand the science.

    The reason for the year-to-year spikes in the temperature plot, and even decade-long periods of seemingly non-rising temperature, is that there are things other than the amount of CO2 in the atmosphere that affect global temperature.

    The el Nino/la Nina see-saw is one of them, with el Nino pumping heat from the ocean into the atmosphere and la Nina doing the opposite. Another is the roughly 11 year cycle between minimum and maximum solar output, and yet another are random volcanic eruptions, which can lower global temperature if they are powerful enough to send material into the stratosphere where it can block sunlight and not quickly be washed out by rain.

    All of those things, and others, take place on top of any steady increase from CO2, hence the spikes and troughs in the plot. At times some of them will be large enough alone or in concert together to cancel out the CO2 increase or to even overcome it for a short period, making it look like global temperature is cooling instead of warming.

    But what if you were to factor these large known natural variations out, removing much of the spikieness that they add to the plot? What the graph would then show would be any remaining natural random variation, plus the steady increase due to CO2. A recent study did just that. Foster & Rahmstorf (2011) removed much of the effect of the above known factors to more clearly show the steady increase in temperature due to increasing CO2. A more in-depth discussion of the study can be found here.

    Another way to reveal the steady increase due to rising CO2 is to just exclude the volcanic eruptions since they are totally random events and last only a year or two, and plot three separate trend lines, one for the warm el Nino years, one for the cool la Nina years, and one for the neutral years. This was done by John Nielsen-Gammon, the Texas State Climatologist. As you can see in the graph, all three trend lines have risen at very nearly the same rate. Note that the most recent cool la Nina year was the warmest on record, and in fact, the last few la Nina years were warmer than all but the most recent two warm el Nino years.

    As a layman, I find these two studies to be very compelling evidence that a) global temperature has and continues to rise steadily despite year-to-year variation and the seeming flat increase of the past few years, and b) that the steady rise is consistent with what has been predicted due to the steady rise in CO2.

  45. 145
    t marvell says:

    tamino (36). That is hardly an unbiased statement. I’ll write more when I have time.

  46. 146
    Dan H. says:

    You could go one step further, and incorporate all the variations from the beginning of the temperature record to see the natural variations superimposed on the steady increase.

  47. 147
    Dan H. says:

    Yes, the trends Santer determined were on the edge of significance. That was the entire point of his paper; to determine the minimum timeframe necessary to seperate a signal from noise. Using the available data at the time of his writing (2010), that timeframe was 17 years. Today, it would be 19 years. Using data through 2008, it would be 16 years, and through 2007, would be 14 years. The trends are not “seesawing,” but becoming longer.

    I am glad that you do not see 17 years as a “magic number.” In the past, I have heard too many people refer to this value as the minimum timeframe to calculate a temperature trend, and that anything shorter is meaningless. Which is not what Santer was showing.

    [Response: You have no idea. The 17 year number was not just a calculation of the last 17 years of the data set they had at the time, but an assessment of the Signal to noise ratio of all 17 year trends. It is highly unlikely that an additional single year's worth of data will impact that since it only adds one additional 17 year trend data point to 15 other data points (or if you do the analysis on monthly data, an additional 12 data points to the existing 180 data points). Additionally, it is not a 'magic number' but the level at which one would expect to see the signal emerge 95% of the time. i.e. even if there is a signal, one time out of twenty one would miss it. - gavin]

  48. 148
  49. 149
  50. 150
    Jim Eager says:

    But that’s what Foster & Rahmstorf and Nielsen-Gammon started with, Dan, but then I’m sure you already knew that. The idea is to make the enhanced greenhouse trend more clear so that it can be quantified, not to hide it among the noise of natural variation so that it can be ignored or wished away.

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