True Lies

I’ve read the written testimony from Judith Curry before a recent meeting of the Environment and Public Works committee of the U.S. Senate. There’s plenty of stuff that gobsmacked me, but let me tell you what astounded me most on my very first reading.


It’s this:


Global sea level has been rising for the past several thousand years. The key issue is whether the rate of sea level rise is accelerating owing to anthropogenic global warming.

I almost can’t believe that she actually said that.

Let me repeat: I almost can’t believe she actually said that. To a U.S. Senate committee.

There’s considerable evidence that sea level has risen over the last few thousand years. Some of you may be familiar with this graph (from Wikipedia, prepared by Robert Rohde of the “Berkeley team” of which Curry is a member):

Holocene0

It shows sea level estimates throughout the holocene (since 9000 years ago). It seems to me that these data don’t make it certain, but do make it very likely sea level has risen (or at least, not fallen) throughout the holocene. But what’s really important is that it enables us to set some limits on how fast sea level has risen in that time.

Since the year 1900, sea level has risen at an average rate of 1.6 mm/yr according to the global sea level data from Church & White, 1.9 mm/yr using the data from Jevrejeva et al., 1.7 mm/yr according to the Ray & Douglas data. Just for the sake of argument, let’s say between 1.5 and 2 mm/yr over the last century plus.

Has it been going that fast — or even close — for the past several thousand years? Let’s add some lines to the graph, representing what sea level would have been if it had been steady, or had been rising at 0.5 mm/yr, 1 mm/yr, 1.5 mm/yr, or 2 mm/yr:

Holocene_Rate

According to the data, it’s possible — but very unlikely — that sea level rose at an average rate of 0.5 mm/yr throughout the last 6,000 years. But it’s not really possible for the rate to have been as high as 1 mm/yr. As for “between 1.5 and 2 mm/yr,” I believe the correct mathematical nomenclature would be “No way.”

It’s obvious, to anybody who knows what the data say, that the rate over the last century plus has been significantly higher than the rate over the past several thousand years. Obvious.

We could also focus on a more recent time span, the last 2,000 years. I managed to find a reconstruction of sea level at North Carolina covering that time period by Kemp et al. (2011, PNAS, 108(27), 11017-11022, doi:10.1073/pnas.1015619108).

SeaLev2k

They provide a smoothed time series (shown above), and the data on which it’s based, so of course I took the data and smoothed it myself in order to estimate the rate of sea level rise:

Rate_2k

Holy high tide, Batman! A hockey stick!

It wasn’t doing much until about the year 1900, but since then it has taken off like a bat out of hell. In other words, the rate increased — which is what we math geeks call “acceleration.” Mentioning “the past several thousand years” highlights the dramatic nature of the change, unless of course all you say about the past several thousand years is that “Sea level has been rising,” you say nothing about how fast compared to how fast it’s rising now, and trust that your audience hasn’t got a clue (which for members of the U.S. Senate is a pretty safe bet).

The fact that “Global sea level has been rising for the past several thousand years” is about as relevant to this issue as the fact that “People died of lung cancer long before there were cigarettes” is to the issue of smoking and health. My opinion: saying that without even mentioning the evidence about the last century’s dramatic increase in the rate is either ignorance on parade, or the kind of mendacity we might refer to as “true lies.”

About these ads

38 responses to “True Lies

  1. Reblogged this on uknowispeaksense and commented:
    Curry is as dishonest as they come. Shes an attention seeker, whoring her credentials for adulation from angry old white men.

    • Curry’s reasoning and hearing testimony are fair game. Piling on sexualized insults with an obviously misogynistic tinge is anonymous web cowardice. I call foul.

      Also dumb, because it hands your opponent good debating ammunition.

      • Sexualised? Pahhh! If Curry was a man Id say exactly the same thing. Besides, morons will find ammunition in anything anyone says.

      • Because, of course, only women can whore. Now, who’s sexualizing here?

      • Definition of “whore” from Merriam-Webster online:

        “1: a woman who engages in sexual acts for money : prostitute; also : a promiscuous or immoral woman”

        Looks good for Ric so far!

        “2: a male who engages in sexual acts for money”

        Hmmm, not so good after all.

        “3: a venal or unscrupulous person”

        And, of course, “person” is a gender-neutral term and this definition reflects accepted use of the word when refering to somone outside of the context of sex-for-money.

        Ric, there are various dictionaries online that you might want to use before accusing people of misusing words in the English language.

        [Response: There's also, often, a difference between the dictionary definition of words, and the way they're interpreted in common usage.

        Personally I prefer that we get back to the science.]

    • Re. gender of “whore”, Cicero famously accused Marc Antony of being a teenage whore in the Senate itself.

      Of course in the end he paid a pretty severe price in death and after as his corpse was desecrated in various ways for that, and other, remarks.

    • Please don’t do this. Women in science face enough difficulties without having to deal with gender-specific insults. Aunt Judy is incompetent and quite probably biased. That is sufficient grounds for criticism. All you’ve done is discredit all future comments I see from you.

      [Response: I agree, women have a hard enough time in science already and we can't afford to waste all that brainpower. And if you want to criticize Curry, there's plenty to say that's purely academic.]

      • FFS. I did not make this about her gender. If Curry was a man I would have accused him of whoring his credentials as well. You do realise that there are male prostitutes dont you? You also realize that prostitution isn’t exclusively limited to sexual activities? At no time did I sexualise it. You went there. I think your inability to understand that discredits all future comments I see from you. See how that works?

        [Response: I didn't read sexism into your comment. But clearly others did. That may (or may not) be sufficient reason to reconsider.

        Regardless, I hope we've all had our say and we can get back to other stuff.]

    • Okay, you didn’t intend for there to be sexism in your comment. But there was. I make the same mistake frequently (hopefully ever less frequently). I would simply suggest we’re more careful in the way we present our ideas to make sure we’re not crossing the line unintentionally.

  2. I suppose Ms Curry might say you cherry-picked North Carolina and that she could cherry-pick a place where sea level didn’t rise much at all, or even fell, or maybe that North Carolina actually sank during the period in question, or that the North Carolina gauge data was adjusted, along with all the other gauge data, to show an acceleration where there was none in the raw data, and the only data that can be trusted is the satellite data, unless you actually used the satellite data, in which case it, too, was adjusted to show an acceleration where there was none in the raw data, and so what, anyway, because the rate of sea rise has always been accelerating and decelerating.

    • Martin Vermeer

      Well yes, she could have said all of those things, but she would have had difficulty doing so truthfully. The reason Kemp et al. used North Carolina was that it was one of the best quality sea-level proxy time series in existence at the time. Of course the caveat must be made that this is local sea level — but could North Carolina’s subsidence really have taken a hike, to the tune of over 2 mm/year, around 1900? And if so, why?

      • The problem I keep running into when refuting speeches like Curry’s with one location, as Tamino did, is argumentum ad whack-a-mole-um. True, she couldn’t truthfully counter with the points I wrote, but she can simply say North Carolina is not the whole world. The people I argue with use that technique. It just starts the argument all over again. Then if I construct an argument that the rate of global average sea level rise is rising, they produce several locations from NOAA where it is not accelerating (by visual inspection). The same people simply wait awhile and then post the same argument again. That’s what this senate hearing was for Curry, a way to rekindle doubt about facets of global warming where there is no doubt.

      • Martin Vermeer,
        You would be correct with your questions given that N Carolina is not the whole world, but only if Kemp et al (2011) were the only attempt to reconstruct millennial SLR&F using salt marsh data (that have continuity & verifiability). But there are others.
        From AR5 5.6.3:-
        “The most robust signal captured in the salt-marsh proxy sea level records from both the NH and SH is an acceleration, late in the 19th or in the early 20th century (Figure 5.17), that marks a transition from relatively low rates of change during the late Holocene (order tenths of mm yr–1) to modern rates (order mm yr–1) (see also FAQ 5.2).”
        Presumably Chapter 5 is another portion of AR5 that Curry has “expertly” failed to account for when testifying, although I note that it is referenced from AR5 3.7 which is where she found her pretty graph.

    • What I used to ask folk to do in this situation is to look at Google Images for CU sea level rise. Just page down and look at the older charts. What do you see? Yes! the farther you go back, the smaller the annual rate of rise.

      Anyone can do it.

      Best,

      D

  3. And to think I considered her a rare breed of rational skeptic for a while. Now I feel dirty.
    Thank you for your relentless work on this and other topics.

  4. The strange thing is that Judith Curry is (or ought to be) aware that sea level is rising much faster now than during the past few millennia. E.g. she linked once to my post which makes very much the same point as you are making: http://ourchangingclimate.wordpress.com/2011/01/18/past-current-future-sea-level-rise-graphs/ I added a straight line with slope 3 mm/year (the current SLR) to the Rohde’s wikipedia graph, showing that current SLR is much higher than the average over the past millennia.

  5. That Wikipedia sea level curve is most probably wrong, and IIRC based upon Fleming (1998). The volume of water in the oceans has been more likely been static throughout the last 5000 years. Local (relative) sea level in the tropics and subtropics fell over this interval as water was siphoned away to fill subsiding regions of the ocean floor. This is why we have coral atolls and ’3 metre beaches’ throughout those regions – they were exposed as local sea level fell.

    Sea level rise of the magnitude indicated in the Wikipedia image, based upon glacial isostatic adjustment (GIA) models, would have eliminated coral atolls and 3 mtere beaches.

  6. Quite simply, a brilliant article.

  7. Curry is an activist, plain and simple. Unfortunately, she isn’t transparent about it.

  8. With Curry’s “testimony” (presumably this means it is a ‘solemn declaration’), you have to ask whether she had determined what to say before or after she sat down at the hearing. I’ve read better constructed argument on Wattsupia than her little rant on sea level.

    In this bit of “testimony” she is supposed to be arguing that AR5 has a weakened case for AGW compared with AR4. So where does Sea Level Rise fit in with this weakening? Nowhere! Because suddenly Curry is arguing for better understanding of SLR to allow policy decisions. But that’s strange because it’s tidal surge that’s the issue affecting policy decisions of the moment. Or did I misunderstand Sandy?

    But even if SLR is a major policy consideration, her grasp of the SLR subject isn’t very good. She doesn’t appear to know that the impact on SLR from pumping dry aquifers didn’t feature in AR4 because until recently dam-building roughly cancelled out the pumping. She doesn’t appear to understand that while SLR may have been momentarily high in the mid-20th century, we know Greenland & Antarctica are now constantly shedding ice at increasingly high rates, rates that already just from those two sources exceed SLR rates of the last century.

    It is only when AR5 discusses mid-20th century SLR that we get where Curry is coming from. After all the uncertainty has been bashed around AR5 says “Although the calculations of 18-year rates of GMSL rise based on the different reconstruction methods disagree by as much as 2 mm yr–1 before 1950 and on details of the variability (Figure 3.14), all do indicate 18-year trends that were significantly higher than the 20th century average at certain times (1920–1950, 1990–present) and lower at other periods (1910–1920, 1955–1980), likely related to multidecadal variability. Several studies have suggested these variations may be linked to climate fluctuations like the Atlantic Multidecadal Oscillation (AMO) and/or Pacific Decadal Oscillation (PDO, Box 2.5) (Holgate, 2007; Jevrejeva et al., 2008; Chambers et al., 2012), but these results are not conclusive.”
    It’s like magic. Make with the incantation “linked … climate fluctuations … PDO” and Curry will appear out of the bottle. And if you listen very hard boys and girls, you might even hear her ‘wishing three grants’.

  9. Judith plays an attention game- read the scientific Judith papers and AGW is real and happening. Perhaps being an average climate scientist that agrees with the consensus doesn’t draw her enough attention.

    Judith the climate change pundit always avoids putting such controversy in peer review but sticks to letters, statements and media sound bites.

    and she can always deflect criticism- she didn’t in this instance say- sea rise is natural – “Global sea level has been rising for the past several thousand years. The key issue is whether the rate of sea level rise is accelerating owing to anthropogenic global warming.”

    the phrase – ‘the key issue’ says it all- for most the key issue is pretty settled but in the bizarre US world where half the government and population are in denial it makes Judith sound reasonable- ‘you have doubts, and so do I’ but lets not commit.

    Judith obviously loves the attention- but from my perspective she sounds like a fence sitting who like stirring up her peers. Reviewing her non- peer reviewed opinion ‘weasel words’ stands out.

    Judith the weasel Curry.

    • Agree re ‘weasel’.

      Isn’t her ‘defense’ that she is not questioning that sea level rise is accelerating just whether it is due to “AGW”? The post strongly highlights that the last century (and past few decades even more so) shows SLR at a much faster pace than the average over the past 5000 years. It does not, it seems to me, directly slap her in the face over her disassociation of SLR from AGW.

  10. With Curry’s “testimony” (presumably thus being her ‘solemn declaration’), you have to ask whether she had determined what to say before or after she sat down at the hearing. I’ve read better constructed argument on Wattsupia than her little rant on sea level.

    In this bit of her “testimony” she is supposed to be arguing that AR5 has a weakened case for AGW compared with AR4. So where does Sea Level Rise fit in with this weakening? Nowhere! Because suddenly Curry is arguing for better understanding of SLR to allow policy decisions. But that’s strange because surely it’s tidal surge that’s the issue affecting policy decisions of the moment. Or did I misunderstand Sandy?

    But even if SLR is a major policy consideration, her grasp of the SLR subject isn’t very good. She doesn’t appear to know that the impact on SLR from pumping dry aquifers didn’t feature in AR4 Table 5.3 because until recently dam-building roughly cancelled out the pumping. Did she not read AR4 5.5.5.4? And she doesn’t appear to understand that while SLR may have been momentarily high in the mid-20th century, we know Greenland & Antarctica are now constantly shedding ice at increasingly high rates, rates that already just from those two sources exceed SLR rates of the last century.

    It is only when AR5 discusses mid-20th century SLR that we get where Curry is coming from. After all the uncertainty has been bashed around AR5 says “Although the calculations of 18-year rates of GMSL rise based on the different reconstruction methods disagree by as much as 2 mm yr–1 before 1950 and on details of the variability (Figure 3.14), all do indicate 18-year trends that were significantly higher than the 20th century average at certain times (1920–1950, 1990–present) and lower at other periods (1910–1920, 1955–1980), likely related to multidecadal variability. Several studies have suggested these variations may be linked to climate fluctuations like the Atlantic Multidecadal Oscillation (AMO) and/or Pacific Decadal Oscillation (PDO, Box 2.5) (Holgate, 2007; Jevrejeva et al., 2008; Chambers et al., 2012), but these results are not conclusive.”
    It’s like magic. Make with the incantation “linked … climate fluctuations … PDO” and Curry will appear out of the bottle. And if you listen very hard boys and girls, you might even hear her ‘wishing three grants’.

  11. Thanks Tamino for once again pointing out the flaws in Dr Curry’s arguments.

    I wasn’t quite sure what to make of Curry until I read one of her previous submissions to congress; a jaw-dropping read. She seems to possess a remarkable ability to present laughable, denialist memes in a way that makes them appear reasonable.

    The basic message from Curry’s testimonies seems to be that it’s all too uncertain for us to do anything about climate change, and any efforts that we make may be futile anyway. In the latest offering the recent slowdown in surface temperature rise is once again misinterpreted as a “hiatus in global warming” (are the rapidly warming oceans suddenly not part of the globe?) There seems to be an assumption that because Curry can piece together a few disparate quotations from AR5 and twist those quotations to suggest that AR5’s overall conclusions are wrong, we don’t need to act now to prevent dangerous climate change.

    Curry’s suggestion that “IPCC AR5 weakens the case for human factors dominating climate change in the 20th and early 21st centuries” seems opposite to the truth.

    It’s clear that we need urgent action to cut greenhouse gas emissions; otherwise there is a big risk that we’ll face very serious consequences in the future. It is nonsensical to suggest that we need more certainty about the exact nature of those very serious consequences before we start taking action.

    • “Thanks Tamino for once again pointing out the flaws in Dr Curry’s arguments.”

      More like Curry’s careful word usage to ‘give the impression of’ a certain viewpoint. That’s what I personally think. I think she knows the truth, and yet for some reason that seems a lot like shilling to me, presents the opposite view when placed in front of congress. I wouldn’t be surprised if it came out later that she’s been paid to have that view.

  12. Horatio Algeranon

    Well, everyone (including undoubtedly Dr. Curry, who reads all the important journals) knows that 20th century horse-diving off Steel Pier in Atlantic City had a major inflationary impact on the measured rate of sea level rise.

    There is some evidence* of squirrel-diving before that during much of the Holocene, but it undoubtedly had a much smaller overall impact, (squirrels being smaller and all)

    *squirrels buried face down in the coastal mud, first discovered by Dr. Willie Swoon (PhD, Disastrophysics)

  13. John Christy is another one who completely misrepresents the pre-20th Century rate of sea level rise, saying it was an inch per decade for the last 15,000 years, which translates to an absurd 5 metres since Roman times – the reality is virtually zero sea level rise for several thousand years up to the 20th Century. His intention is the same as Curry, I would guess – to minimise the significance of the current ~30mm per decade rate of global sea level rise.

    Isn’t there a law against deliberately misleading the US Senate?

  14. Jeffrey Davis

    Perjury is a criminal act. One can avoid the crime of perjury by uttering true statements. A lie is a moral one. It’s possible to lie even though the words you say are true. Not telling all of the truth when the complete truth would give a different impression has anciently been considered a lie.

    • It is not perjury to say “I believe the data say [...fill in the blank...].”

      Perhaps this is unfortunate.

  15. skeptictmac57

    Curry’s disreputable message is basically three ‘doubt’ incantations:

    1)Climate scientists don’t take into account natural variability (B.S.)

    2)Climate models cannot be trusted (although she uses them in her own business)

    3)Most climate scientists are motivated to only look for signs of AGW because that’s where all that cushy grant money comes from and no one would fund research that wouldn’t support AGW. (Which is an insult and slander to science in general and climate science specifically.)

    Her bottom line ,putting all of this together, is that climate science if fraught with uncertainty and venally motivated researchers whose life work is a house of cards built on a foundation of sand. But she says all this without that kind of bluntness so she can be seen by some as a ‘reasonable’ and ‘fair’ ‘skeptic’ who is “Just asking questions”.

  16. I thought Curry had left the BEST team?
    Any update on that?

    • Horatio Algeranon

      “BEST to WORST”
      – by Horatio Algeranon

      Left the BEST
      To join the WORST
      A skeptic fest
      That’s well rehearsed

  17. Was that sworn testimony? (It’s highly unlikely that it was)

  18. Thanks, I really, really like time-series graph sequences that include first-derivative graphs, since that turns eye-balling of diagonal lines into levels on rate graphs, and the rates are often more directly tied to physical processes than are the actual levels.
    I.e., it might be theoretically possible from statistics for wild fluctuations to happen, but the physics makes it very hard, i.e., relevant to Marcott, et al

    [Response: Taking derivatives does tend to amplify the noise, so it can get tricky. But I agree, in some situations it's worthwhile to plot estimated rates, not just let people "eyeball" the slope of a smoothed plot.]

  19. Re: noise: yes, but maybe you can do some smoothing before doing derivatives or estimate by doing N-year regressions centered on year and plotting the slopes, and picking a few different N’s to get something useful.

  20. Let us also stop with the disrespectful “Aunt Judy” crap. Please. Curry’s science, in and of itself, gives us plenty of ammunition against her oft-wrong conclusions.

    • Ironically the only other use of that phrase in these comments was by the person complaining about the language used by someone else and making much the same point as you…