Open Mind

Embarrassing Questions

June 26, 2009 · 29 Comments

The decade of the 2000s is almost over; there’s only a bit more than 6 months to go. This decade has witnessed the hottest year on record (2005), the lowest summer arctic ice extent ever observed (2007), and the highest sea level in recorded history (2008, although data for 2009 are not yet available). It has also seen a war against truth and the scientific community, waged by the forces of ignorance and dishonesty who deny that global warming is real, is man-made, and is dangerous.

A few of the assault leaders are scientists (but when they opine on global warming their scientific expertise and objectivity abandon them or is banished); many are capitalists attached to “free markets” as an ideology who see any attempt to mitigate climate change as a threat to the fossil-fuel-based economics which is the source of their obscene wealth; some are politicians, who are probably motivated by the same free-market ideology which, frankly, gives capitalism a bad name.


One such politician is Australian senator Steve Fielding. He recently attempted to embarrass Australian Climate Change Minister Penny Wong by posing three “questions” which were framed by a fellow Aussie denialist, “scientist” Bob Carter. I put “scientist” in quotes because in spite of Carter’s scientific credentials, his statements regarding global warming are so amateurish as to cast doubt on his qualifications to opine on any scientific topic. The word “questions” likewise merits quotes because they really aren’t questions at all; they’re a transparent attempt to suggest what’s false as though it were true in an effort to embarrass global warming science. They’re so patently false that the real embarrassment is for those who pose them.

Let’s look at the very first “question”:


1. Is it the case that CO2 increased by 5 per cent since 1998 whilst global temperature cooled over the same period? If so, why did the temperature not increase; and how can human emissions be to blame for dangerous levels of warming?

Of course Carter chooses to start with 1998; that was the year of the huge el Nino, causing it to be quite a bit hotter than the prevailing trend due to a random, and entirely natural, fluctuation. Carter doesn’t hesitate to use natural fluctuation to his advantage; he has deliberately chosen an extreme maximum as his starting point to give the impression that global temperature has cooled. This is an example of the kind of dishonesty called “cherry-picking.” How sad that someone who purports to be scientific has to resort to this kind of subterfuge.

The pathetic part is that even the subterfuge doesn’t make the “Is it the case” claim true. Using the very HadCRU temperature data referred to by Carter, the average temperature for the 1st half of the period in question (1998 to the present) is 0.4012 deg.C, while the average for the 2nd half of the period in question is 0.4138 deg.C. The 2nd half of the time period in question is still warmer, in spite of the time span starting with an immensely strong el Nino and ending with a la Nina — even with the most favorable (to their case) possible juxtaposition of natural variations, the claim “global temperature cooled” is either wishful thinking or deliberate deception. What it’s NOT is: true.

The HadCRU time series omit the arctic region, the fastest-warming area of the globe; that’s one of the reasons I prefer GISS data, for which the average temperature during the 1st half of “since 1998″ is 0.4588 deg.C while the average for the 2nd half is 0.5300 deg.C. Again, NOT cooler.

Carter also omits to mention any estimate of the uncertainty associated with trend estimates over such a brief span of time. The rather verbose and even more misleading Assessment of Minister Wong’s Written Reply actually contains this ludicrous falsehood:


It is the IPCC who have previously denied the effect of natural variability.

This is as false as it gets, people. The IPCC has never denied the effect of natural variability, in fact the IPCC reports discuss it extensively. The “Assessment” goes on to say


For example, the 2001 Summary for Policymakers claimed, based on computer model simulations, that the climate system has only a limited internal variability. In turn, this claim was, and is, used to underpin the argument that carbon dioxide forcing is the only plausible explanation for the late 20th century warming trend.
For the government to now invoke natural variability as an explanation for the elapsed temperature curve is to destroy the credibility of their previous arguments for carbon dioxide forcing.

Natural variation is limited — too small to explain late 20th century warming — but that doesn’t mean it’s not big enough to explain the natural fluctuations “since 1998.” It’s hard to tell whether Bob Carter is ignorant enough to believe this argument, or he just thinks we’re all a bunch of idiots.

Bob Carter just might be the world’s loudest repeater of the “global warming stopped in 1998″ mantra. But he’s hardly the only one who loves to make pronouncements about trends based on data covering far too short a span of time. In fact the GISS data “since 1998″ show a trend rate of 0.009 +/- 0.016 deg.C/yr; that’s somewhere between actual cooling (at -0.007 deg.C/yr) and warming way-faster-than-anyone-believes-even-me (at 0.025 deg.C/yr). This tells us only two things: 1st, the trend “since 1998″ is totally consistent with the trend since 1975, and 2nd, the time span in question is way too short to give any meaningful information about temperature trends. Bob Carter might know a thing or two about sedimentology, but in statistics he gets an F. Minus.

Why the obsession with trends over short time spans? For some, it’s because they want the most up-to-date estimates possible and they honestly don’t know how meaningless such results are. For Carter and his ilk, it’s because that’s the only way they can possibly hope to confuse people about a trend which, on time scales which are long enough to be statistically meaningful, are blatantly obvious. So they start with the biggest el Nino and end with a la Nina to take maximum opportunistic advantage of natural variation, keep the time span short to take maximum statistical advantage of natural variation, then whine when it’s pointed out that natural variation is at play.

Whine even louder when it’s pointed out that even with a cherry-picked starting point and too short a time span, “global temperature cooled” STILL isn’t true.

I’ve often posted about the uncertainty in trend estimates, and the inevitability of random noise giving the false impression of cooling on short time scales. Perhaps it’s useful to take a look at what actual global temperature looks like on short time scales. Let’s look at some decades, the 1970s through the 2000s. I’ll plot all decades on the same scale for both axes; here are annual average temperatures from GISS for the 1970s:

giss70

Linear regression gives a positive slope, at 0.0065 +/- 0.0224 deg.C/yr, but the error limits are way too big to draw any meaningful conclusion and the visual impression of the graph doesn’t indicate warming or cooling, just a lot of jiggling around. That’s natural variation for you; a lot of jiggling around which makes trend estimates on short timescales too imprecise to be useful. The 1980s gives a nearly identical impression:

giss80

Again the linear regression slope is positive at 0.0067 +/- 0.0219 deg.C/yr, again the uncertainty is much larger than the estimate, and again the visual impression is neither warming nor cooling, just a lot of jiggling. For the 1990s we have:

giss90

The untrained eye may get the impression of a meaningful warming trend. But the linear regression trend rate is 0.0179 +/- 0.0276 deg.C/yr, so the error range is still considerably larger than the estimate. From these data, we’d estimate global temperature change as somewhere between rapid cooling (-0.0097 deg.C/yr) and oh-my-god-we’re-all-going-to-fry warming (+0.0455 deg.C/yr). For the 2000s we have:

giss00

This time the linear regression trend rate is 0.0126 +/- 0.0218 deg.C/yr, so once again the uncertainty is much larger than the estimate. It is worth noting that of these four decades, the 2000s don’t have the smallest linear regression trend rate, they have the 2nd-largest.

What’s the cure for “too short to tell” time spans? Longer time spans! Here’s the data from 1970 to the present:

giss39y

Clearly a decade is too brief a time span to get a meaningful trend estimate; just as clearly the trend since 1970 is — how shall one say? — obvious. The linear regression trend rate is 0.0164 +/- 0.0028 deg.C/yr. I have good reason to believe that the “turning point” marking the start of recent warming is 1975 rather than 1970, but even with this earlier date the trend is statistically significant. Strongly. And it’s warming, not cooling. We can even graph the residuals from this linear fit:

gissres

The residuals certainly don’t give the visual impression that the last decade, or “since 1998,” or any other episode, represents a departure from the overall trend. They don’t support that idea statistically either.

We can reduce the noise level by taking averages over longer time spans, as I’ve often mentioned. Here are 10-year averages since 1970:

giss10y

Pay attention, Bob Carter: THIS IS WHAT GLOBAL WARMING IS ABOUT. IT’S NOT ABOUT LESS-THAN-A-DECADE NATURAL FLUCTUATION, IT’S ABOUT THE INEXORABLE INCREASE FROM DECADE TO DECADE.

In case you’re interested in how the 10-year averages compare to the 1-year averages, here they are together:

giss10yb

In case you’re interested in both the location and the variation of temperature within each decade, here are “box-and-whiskers plots” for each decade:

boxplot

The box extends from the 1st quartile (the 25% probability point) to the 3rd quartile (the 75% probability point) with the thick line in the middle indicating the median value (the 50% probability point). The “whiskers” extend to the smallest and largest values which are not potential “outliers.” Outliers are often identified as points which are more than 1.5 times the “interquartile range” below the 1st quartile, or above the 3rd quartile, with the interquartile range being the difference between 1st and 3rd quartiles. The outliers are plotted as small circles. Only the 2000s have a potential outlier; the year 2000 was quite a bit cooler than the rest of the 2000s.

It’s appropriate to end this post with a quote from Timothy Chase in recent reader comments:


… anyone who tries to establish the trend in global average temperature with much less than fifteen years data is — in my view — either particularly ignorant of the science, or what is more likely, some sort of flim-flam artist …

That certainly includes Steve Fielding and Bob Carter. At least Fielding has an excuse; he’s “particularly ignorant of the science.” As for Carter …

Categories: Global Warming
Tagged:

29 responses so far ↓

  • Deep Climate // June 26, 2009 at 3:53 am | Reply

    Carter, a retired geology professor, is a “scientific advisor” for the Canadian “astroturf” group, Natural Resources Stewardship Project (NRSP) and for the “skeptic” umbrella group International Climate Science Coalition (ICSC). The NRSP was started by Canadian PR specialist Tom Harris, who is now Executive Director of the ICSC.

    The pair organized the infamous Bali Open Letter to the U.N., released in the dying days of the UN climate change conference in 2007. The open letter was released through the Canadian right-wing newspaper National Post, which hid key details of the letter’s provenance from readers.

    See:
    http://www.sourcewatch.org/index.php?title=Natural_Resources_Stewardship_Project#Bali_open_letter_to_U.N.

    Also see:
    http://deepclimate.org/2009/06/16/freeman-dysons-shadowy-canadian-connection/

    sigh … yet another battle in the ongoing “War on Science”.

  • KenM // June 26, 2009 at 6:19 am | Reply

    I don’t challenge your overall analysis, which, as a non-expert and a laymen, I find impressive ….

    However, with regard to cherry picking El Nino vs La Nina years … isn’t ENSO a regional variation? Cooling in one part of the ocean offset by warming in another? Shouldn’t global averages be consistent regardless?

    What does it mean to cherry pick years in the context of ENSO and global averages?

    Not that it matters much, since your analysis of the overall trend vs 10-year slices is compelling on its own…

    [Response: Although el Nino is regional with respect to ocean temperatures, it allows for greater heat exchange between the ocean and the atmosphere -- hence it has a considerable effect on global average surface air temperature (the most common measure of global warming). You might be interested in this.]

  • Chad // June 26, 2009 at 8:30 am | Reply

    Hey Tamino, what program do you use for your analysis?

    [Response: I still use a lot of programs I've written myself (for methods of my own devising), but these days I mainly use R. It's free for the download, easy to learn, and immensely powerful. If you're interested in acquiring it, google "CRAN" (the comprehensive R archive network); there are versions for both PCs and Macs.]

  • TCO // June 26, 2009 at 1:03 pm | Reply

    Tammy:

    I think the main thing with the denialists is them not being intellectually honest, about them beleiving in things that go their way, looking for things that go their way, only looking for faults in opponents arguments never their own.

    I think this is really a common human nature aspect. Not just that of the right or of GW denialists. You see the same behavior with those who think the WMDs must still be out there, in Syria or something…or that the CBS Bush memos were typed, not written in MS Word.

    I’ve just had a devil of a time pinning them down on a rather minor theoretical point, where they made an overstatement.

    http://noconsensus.wordpress.com/2009/06/09/tired-and-wrong-again/#comment-7481

    I do think that they actually float rather interesting issues and concepts to the fore and pick away at the details of papers in a way that forces understanding the guts of them, rather than taking a Nature or Science (which are so short they are press releases) pub for granted. The bad thing is that they overstate their cases. That they don’t realize that often the best they can come up with is a middle ground (uncertainty) rather than a smoking gun to their side.

  • george // June 26, 2009 at 1:58 pm | Reply

    The ten year average method is simple and clearly shows what is going on with global temperature over the past few decades.

    A linear regression of the ten year average values over the entire period gives pretty much the same slope as the linear regression of all the data points over the same time span.

    Most importantly, it averages out the short term noise and when it comes to estimating the trend, actually prevents using less data than 20 years of data (since 10 years are required for each decade value)

    As a result, if one uses ten year averages to illustrate what is going on with the climate, one avoids the “debate” about short trends entirely. Perhaps most importantly, one avoids the (vacuous) “arguments” about the “trend since 2001″ (or even 1998), which are so popular in some circles).

    The 10 year average method seems almost ideally suited to the case at hand. So I am puzzled why those who are honestly trying to represent what is going on with the climate seem to focus so often on trying to trend yearly (or even monthly) temperature values.

    I understand the advantage of using yearly or monthly values for the entire period if you want to estimate uncertainty of the trend, but for illustrating to someone who has no background in all the abstruse statistics, it would seem far better just to show the ten year averages and perhaps a trend line through those.

    [Response: I think you're right that scientists have done an excellent job communicating with themselves but a poor job communicating with the public. The scientific instinct is to use maximum available information (which means monthly data) and apply heavy-duty statistics to show what's meaningful and what isn't. I've done so myself, but that leads to discussion of autocorrelation and ARMA models for the noise and their impact on confidence limits of regression analysis ... which for the general public, can make them roll their eyes in boredom and even suspect we're "pulling a fast one." Only lately have I come to appreciate the value in "KISS: keep it simple, stupid!"]

  • lweinstein // June 26, 2009 at 2:03 pm | Reply

    [edit out a tediously long list of ludicrous misstatements of fact, which would make the most die-hard denialist proud, culminating in this annalysis:]

    … The present trend seems to have peaked about 2003, …

    [Response: If you can make this statement after reading this post (did you even read it?), then there's no hope for you to return from beyond "the threshhold."

    This is what we're up against, folks: those who are blind because the will not see.]

  • David Larsson // June 26, 2009 at 3:59 pm | Reply

    Thanks, as another non-expert, I found this post (which I learned of via the hyperlinked phrase “more cherries” on Gavin’s Real Climate blog today) very helpful. Today’s WSJ, for example, speaks in hushed and reverent tones of Mr. Fielding in an editorial subtitled “The number of skeptics is swelling everywhere,” and asserts that “the inconvenient truth is that the earth’s temperatures have flat-lined since 2001, despite growing concentrations of C02. ” While my expectations of the accuracy of factual assertions contained in that particular section of that particular publication are admittedly low to begin with, the information in the above post gives me a much better appreciation of the great care that the WSJ editorial board takes to back up its assertions with data — reminiscent of the precision behind the statement “I did not have sexual relations with that woman.” Downright Clintonesque. Admirable, really.

  • Deep Climate // June 26, 2009 at 4:19 pm | Reply

    Here’s one of the statements in the Bali Open Letter (organized and presumably written by the NRSP’s Bob Carter and Tom Harris):

    “Leading scientists, including some senior IPCC representatives, acknowledge that today’s computer models cannot predict climate. Consistent with this, and despite computer projections of temperature rises, there has been no net global warming since 1998.” [Emphasis added]

    The statement was signed by 100 scientists, engineers and economists including “usual suspects” like Carter, Freeman Dyson, “IPCC expert reviewer” Vincent Gray and Don Easterbrook (list below):

    http://www.nationalpost.com/news/story.html?id=164004

    In the Bali open letter, Carter listed himself as “Professor, Marine Geophysical Laboratory, James Cook University, Townsville, Australia”.

    In fact, Carter retired in 1999 and now has the “largely honourary” title of Adjunct Professorial Research Fellow at JCU. Furthermore, JCU policy on Adjunct Appointees states:

    “Adjunct titles shall not be used outside of University related business … appointees should not use a University title in their normal professional capacity but limit their usage to involvement in University activities.”

    Some time ago, I wrote JCU to protest the apparent misuse of Carter’s university title, but received no answer.

  • Ian Forrester // June 26, 2009 at 5:45 pm | Reply

    Here is another signatory to that letter. someone who should know better:

    “Edward J. Wegman, PhD, Department of Computational and Data Sciences, George Mason University, Virginia.”

    Just how honest is this “statistician” who deniers say has shown the statistics used by Mann to be wrong? How can anyone who claims to be a statistician agree with the contents of the Bali letter?

  • Anna Haynes // June 26, 2009 at 9:04 pm | Reply

    re the motives of delayers –

    I’m probably going to regret this, but it _could_ be a smoking gun. If you could take a look and give me your interpretation, I’d be most grateful.

    I’ve been digging behind one delayer-friendly meme that Tierney spread in his NYTimes blog last year, right before the Heartland conference – namely, “the more informed you are about climate change, the less you worry”. Last month I documented what I’d found in this Daily Kos post.

    As part of that investigation, I made a public info request to Texas A&M for email correspondence involving the post-publication publicity for the paper whose soundbite meme Tierney was spreading; and they gave it to me, albeit slightly (family members’ names/relationships) redacted.

    One particular email exchange between the paper’s Author#1 and Tierney made no sense to me whatsoever – but now I see there’s at least one explanation, which, if correct, would appear to be a smoking gun.

    But I could be wrong – it’s more than likely that there’s another interpretation that I haven’t thought of. So please, please help keep me from making a mistake that’d make me look extremely foolish – tell me, what do you think is being said here?

    Context:
    From content and tone of the emails, Tierney and Author ostensibly don’t know each other.

    The paper gets published. Tierney emails Author expressing interest and asking a few Qs about it. Author answers. Tierney does his blog post about the paper. We commenters who went and read it proceed to pile on, pointing out the paper’s glaring flaw (namely, the self-reported nature of the climate “informedness” metric).

    Then:

    Author emails Tierney saying, “i think the post reads just great”, then adds:

    ———

    “I notice that it’s racking up the comments, too.
    One of my [redacted] promised (hopefully facetiously) to post something about how the study is flawed due to a childhood nickname. The risk of telling one’s [redacted] about these things, I suppose.”

    Tierney responds “I try to keep ad hominem attacks out of the comments, so he probably wouldn’t succeed anyway.”

    ———

    Question for Open Mind readers: how can you interpret the “childhood nickname” comment, and Tierney’s response, in a way that makes sense?

    [Response: I think such discussion belongs on an open thread. So I've started a new one, just to make it easy. Readers who wish to respond should do so there.]

  • Gareth // June 26, 2009 at 11:01 pm | Reply

    Carter feels free to make the most outrageous claims about global temperatures – and this latest example is far from the most egregious. I blogged about his biggest lie back in April, when he wrote this:

    First, there has been no recent global warming in the common meaning of the term, for world average temperature has cooled for the last ten years. Furthermore, since 1940 the earth has warmed for nineteen years and cooled for forty-nine, the overall result being that global average temperature is now about the same as it was in 1940.

    And he says all this in a persuasive voice and with a straight face. I sometimes wonder if he isn’t (along with Monckton) a parodist playing a very deep game…

  • Nathan // June 27, 2009 at 1:01 am | Reply

    Being an Australian I am embarrassed by Steve Fielding. Thankfully we will have an election late next year and he will be removed from parliament. By a series of strange events he was elected to the Senate with only 2.1% of the votes. He certainly represents very few people, mostly fundamentalist Christians. Sadly because of how the election panned out he has the balance of power in the Senate, and is doing his best to block anything the Aussie Govt does on it’s emissions trading scheme. Soon we will all be able to ignore him, just not this year.

    [Response: Most nations have some politician to be embarrassed about; senator Inhofe comes to mind. In fact, until recently in the U.S. our biggest embarrassment was the president.]

  • Bertus // June 27, 2009 at 5:53 am | Reply

    Steve Fielding is a national embarrassment and hopefully won’t be in the Parliament much longer.

    Just a small technical question: in your fifth graph (temperature anomaly 1970 – 2010) it shows a year, looks to be about 2005, which is HOTTER than 1998. Is this so? I thought ‘98 was the hottest year on record.

    [Response: These are GISS data, and in the GISS data set the hottest year on record is 2005 (as mentioned in the introduction)]

  • Geoff Russell // June 27, 2009 at 6:03 am | Reply

    Great post. But you need to explain “residuals” for people who’ve never studied such things. Briefly, if people
    look at Tammino’s plot of GISS from 1970 to 2010. The “residuals” are the differences between the temperature data points and the red line. If a data point is above the red line, the residual is positive, and if it is below, then the residual is negative.

    If the residuals tend to be more positive than negative (or vice versa), then the trend (the red line) is changing. If they look randomly spread above and below zero, then the trend is constant.

  • Deech56 // June 27, 2009 at 11:07 am | Reply

    It amazes me that we need to see the same analysis time and time again – our host is truly patient. Embarrassing politicians aside, the US took a major step yesterday with the House’s action on Waxman-Markey. It’s not perfect and there are still pitfalls ahead, but it’s a start.

    I’ve read that public opinion on climate varies with the perception of short-term effects, and I’d like to think that maybe the points that Tamino has made here and in other posts have fallen on receptive ears, so I guess our host’s patience is justified after all. I am probably not the only one who has linked to earlier “Open Mind” regression analyses.

    My hope is that we will have a mechanism in place for starting to address future climate change and that we will have some credibility going into the Copenhagen Conference. Warming will continue, and the phenomena and cycles that have affected global temperature over the short term will cause warming above the trend line – even the denialists will have to sit up and take notice.

    • Duane Johnson // June 27, 2009 at 9:01 pm | Reply

      Deech56

      Your hope that global warming exceeds the trend line reveals a motivation that conflicts with the supposed purpose of the conference. Isn’t it the position of most AGW proponents that we’ll be better off with less warming? Or are other political objectives involved?

  • dhogaza // June 27, 2009 at 10:03 pm | Reply

    Your hope that global warming exceeds the trend line reveals a motivation that conflicts with the supposed purpose of the conference. Isn’t it the position of most AGW proponents that we’ll be better off with less warming? Or are other political objectives involved?

    Get yourself a clue-by-four and whack yourself in the head with it until you understand English.

    Here’s Deech56’s hope:

    My hope is that we will have a mechanism in place for starting to address future climate change and that we will have some credibility going into the Copenhagen Conference.

    He hopes that we (the US) will have legislation in place.

    Then he states a fact:

    Warming will continue, and the phenomena and cycles that have affected global temperature over the short term will cause warming above the trend line – even the denialists will have to sit up and take notice.

    Not a statement of hope, but of fact.

  • Deech56 // June 27, 2009 at 10:28 pm | Reply

    Duane Johnson, you are misreading my post. My hope is that we have a mechanism for reducing CO2 in place – my expectation is that when El Nino and the next solar cycle kick in, global temperature will be above the trend line. When that happens, or when we have another bout of major Arctic melting, the denialist position will be that much more difficult to defend.

  • michel lecar // June 28, 2009 at 9:27 am | Reply

    There is really no such phenomenon as ‘denialism’ about climate change. There are no ‘denialists’. There are people who, for good or bad reasons, sincerely take a different view of the evidence from you.

    To label this as thoughtcrime convinces no-one who was not already convinced, and lends an unpleasant air of religious or ideological fanaticism to the controversy.

    It is perfectly possible to be informed, rational and sincerely motivated, and take, rightly or wrongly, a different view of the extent and cause of climate change from the one taken here and on Real Climate. Or to remain puzzled by the evidence and find it not pointing unambiguously in one direction. It serves no useful purpose to deny this.

    Reasonable people may differ on this one. Perpetually shouting that they may not is not a contribution to the debate.

    [Response: Is there no such thing as "denialism" about the earth not being flat?

    Certainly there are people who sincerely believe earth is flat. Are they "informed" and "rational"? Or are they simply in denial?]

  • Ray Ladbury // June 28, 2009 at 1:25 pm | Reply

    Michel,
    Horse Puckey. If someone is confronted with the evidence and DENIES it, they are a frigging denialist. If they embrace every hare-brained scheme that comes along to keep from having to face the evidence, they are a denialist.

    You say “It is perfectly possible to be informed, rational and sincerely motivated, and take, rightly or wrongly, a different view of the extent and cause of climate change from the one taken here and on Real Climate.”

    OK, Michel, show me someone who actually understands the evidence who is not concerned that we are altering the climate. And sweetie, here’s a hint. You don’t meet the prerequisites.

  • Lazar // June 28, 2009 at 1:43 pm | Reply

    michel,

    There is really no such phenomenon as �denialism’[...] sincerely take a different view of the evidence

    wrong michel… there are people who knowingly lie about the evidence… and people who have no interest in studying because evidence contradicts their daft beliefs…

  • Briso // June 28, 2009 at 1:44 pm | Reply

    Tamino wrote:
    “It’s appropriate to end this post with a quote from Timothy Chase in recent reader comments:

    … anyone who tries to establish the trend in global average temperature with much less than fifteen years data is — in my view — either particularly ignorant of the science, or what is more likely, some sort of flim-flam artist …”

    So 15 years is acceptable. How much less than 15 years is unacceptable? 14 years? 13 years? 12 years?

    [Response: The quote indicates that less than 15 fails, not that 15 succeeds.

    It's a mistake to attempt to define a set time limit. It depends on specific circumstances and depends strongly on what variable is being studied.

    The whole "x works but x-1 doesn't in all cases" idea is a simpleton's approach to the issue; one should run the trend analysis AND compute valid confidence limits, then draw conclusions. And even that's probabilistic, not conclusive (although with enough time the "false alarm probability" becomes ludicrously small).

    The simpleton approach is a recurrent tactic of denialists -- but then, that's their target audience.]

  • dhogaza // June 28, 2009 at 1:52 pm | Reply

    There is really no such phenomenon as �denialism’ about climate change. There are no �denialists’. There are people who, for good or bad reasons, sincerely take a different view of the evidence from you.

    Quit lying. It’s tiresome.

  • 12Volt // June 28, 2009 at 1:59 pm | Reply

    NRSP= Not Real Science People

  • Boris // June 28, 2009 at 2:12 pm | Reply

    michel,

    Denialism is a rhetorical strategy:

    “Denialism is the employment of rhetorical tactics to give the appearance of argument or legitimate debate, when in actuality there is none. These false arguments are used when one has few or no facts to support one’s viewpoint against a scientific consensus or against overwhelming evidence to the contrary. They are effective in distracting from actual useful debate using emotionally appealing, but ultimately empty and illogical assertions.”

    http://scienceblogs.com/denialism/about.php

  • Ray Ladbury // June 28, 2009 at 4:05 pm | Reply

    Michel says, “There is really no such phenomenon as â€?denialism’ …”

    Wow, Dude, you are even in denial about denialism.

  • Timothy Chase // June 28, 2009 at 4:30 pm | Reply

    There is really no such phenomenon as ‘denialism’ about climate change. There are no ‘denialists’. There are people who, for good or bad reasons, sincerely take a different view of the evidence from you.

    Michel,

    There are still those who deny that the earth revolves around the sun — or at least since 2000 — and I am embarrassed to say that some of them are in the UK. And of course they likewise are in denial that men landed on the moon. Interestingly enough one of them personally emailed me while I was working with the British Centre for Science Education — because he also opposed evolutionary biology. (I said to myself, “I know that name sounds familiar.”)

    Phillip E. Johnson is an olde earth creationist who is clearly in denial that evolution took place and invented intelligent design as a cover for a movement of which the good majority are young earth creationists. However, he is not simply in denial regarding the discoveries of evolutionary biology but also that HIV causes AIDS.

    Roy Spencer has been in denial regarding global warming, originally that it was taking place and now with respect to its severity and the fact that it is man-made. He is also a creationist who endorsed intelligent design as scientific, and as such he is in denial when it comes to evolution.

    There are those who are in denial about special relativity, general relativity and quantum mechanics. I know because they were quite common in the “Objectivist” movement that I belonged to for thirteen years — and it violated their “neo-Aristotelean” view of the world.

    And then there are those who are in denial when it comes to either the fact that the holocaust took place or to its scale. In the United States many of these people are also in denial when it comes to the fact that the confederacy lost the civil war.
    *
    The evidence for the conclusions that each of these groups of denialists are in denial of is overwhelming. To deny these conclusions is indicative of either considerable to extreme ignorance or of some form of irrationality.

  • George D // June 29, 2009 at 11:52 am | Reply

    If you want a laugh, have a look at the Facebook group ‘Steve Fielding does not exist’.

    http://www.facebook.com/home.php#/group.php?gid=221725975556&ref=ts

  • Bob meade // June 29, 2009 at 12:57 pm | Reply

    Can we go back further than 1970? In Australia we have excellent temperature data back to about 1901 and reasonably credible data back to about 1870.

    Why only go back to 1970?

    Would not a longer time span have more credibility and smooth out the problem of where in the niño cycle the analysis begins?

    [Response: The analysis can be extended long before 1970, but then the trend is demonstrably nonlinear so it becomes more complicated. But it doesn't affect the result one whit; global warming is *still* not about the decade-scale fluctuations, it's about the changes from decade to decade. Claims that it's stopped based on ridiculously short time spans are still ridiculous.]

Leave a Comment