Crash Override

I’ve recently read a book which opened my eyes, and impressed me with a level of enlightenment and self-awareness I haven’t seen since I watched the film “Gandhi” (I’ve watched it at least 20 times). The book is Crash Override by Zoë Quinn. I recommend you buy it and read it.

She tells the story of suffering through online abuse, which was perpetrated by an angry ex but also helped launch the “gamergate” crusade of online abuse against women in the gaming industry. She not only survived the abuse, she not only recovered her “muse” as a game developer, she has started an organization to help victims of online abuse, the “Crash Override Network.”

Many things about her story struck me. Most immediate was the similarity between the online behavior of abusers, and of the climate denier community. Don’t get me wrong, we don’t have it anywhere near as bad as abuse victims, but the similarities of tactics and techniques is compelling. Climate deniers regularly emply the strategy of “DARVO” — deny, attack, reverse victim and offender.

It’s telling, I believe, that claims from deniers to be “only interested in the science” are so regularly accompanied by (surprisingly often dominated by) character assassination. Attempts to discredit the temperature record don’t stop with claiming errors or sloppy science, they almost inevitably descend to accusations of outright fraud. As Quinn points out, transforming something from “the scientists totally got it wrong” to “they’re lying to get money/power” will get readers “riled up,” get them angry, which is a potent technique to transform a large group into an angry mob.

There’s much to be learned from this book. If you sincerely want to help end online abuse, it’s a must read. A key point, which can’t be overemphasized, is that honest attempts to help can all too easily backfire and end up making things worse. Before you do anything to “help” such victims, get permission first. And, learn more about it. Don’t shoot from the hip with righteous indignation — that’s not helping, it only serves your own righteous indignation.

What’s most impressive is the amazing degree of perspective she shows. She constantly points out that claims should be checked, that we shouldn’t assume the worst about a possible abuser without actual evidence.

The most important part might be chapter 13, in which she shines a light on the fact that all of us are liable to become abusive when we’re absolutely convinced that we’re “good and right” while the opposition is “bad and wrong.” That’s how the mob itself gets so fired up they can do such horrible things — they think they’re the “good guys” and their victims deserve worse than they get.

Consider Anthony Watts. In my opinion, he’s not only completely wrong about climate change and astoundingly incompetent as an analyst, he has also done many things I regard as reprehensible. And he doesn’t seem to like me either!

But, as Zoë points out, he is a human being. He’s susceptible to the same emotional outrage that we all feel when we’re sure we’re right and our adversary is wrong wrong wrong. It’s the kind of outrage that enables people to do things that, in the light of day, they’d be ashamed of.

I am hardly a saint. I’d guess that among climate bloggers I’m known for three things: skill with statistics, love of graphs, and a real talent for snark. I’m hardly James McNeill Whistler or Oscar Wilde, but I am pretty good at it.

I’m not feeling especially good about that right now. I wonder, how many opportunities have I missed? How many outside observers see only snark on both sides, so the factual rebuttal of nonsense gets lost in the hatefulness of the argument? I can at least take credit for an unshakeable dedication to non-violence.

Gandhi said of the British, “I want to change their minds, not punish them for weaknesses we all possess.” He also said, “I’ve found that we’re all such sinners, it’s best if punishment is left up to God.”

I also remember quite recently a reader asking a simple question, who was nearly rebuffed. I know as well as you do that “trolls” often impersonate such people to derail discussion and/or start an argument. But which is more important: a speedy put-down of the troll, or genuine help to those who seek it? Helping one person learn more about how and why climate is really changing, is worth putting up with a thousand trolls. And, trolls can’t keep up the pretense for very long. On this blog, we’ll know soon enough and then they’ll simply not appear on this blog.

I want this blog to be a safe space to ask honest questions. I want an environment where those who sincerely want help to feel welcome.

And, I want to reach, actually to reach, some of the deniers. There’s not one among us (unless there’s another Gandhi out there) who can’t say, “There, but for the grace of God, go I.” So let’s start listening to them. We often do so in a particuar “listening mode” where we’re not trying to understand them, we’re just probing for weaknesses. Try just listening — and keeping your mouth shut — and we might find some enlightenment worth having. I doubt we’ll learn anything about climate science from them, but we could learn a lot about how and why people become so fervent about false ideas.

Perhaps most important, let’s stop heaping hatred on them so much. Even I am weak enough that I’ll make exceptions for that — I wouldn’t ask you to stop heaping abuse on Marc Morano — but I fear I’m wrong about even him. As for Anthony Watts, he’s a guy, he wants a good life for himself and his family, he does NOT beat his wife or abuse his dog. He’s misguided, and if he’s nasty about it, don’t forget we can be nasty too. Before we even consider any attempt personally to hurt him or anyone else, remember these wise words: let him who is without sin, cast the first stone.

I doubt I’ll be able to live up to the lofty ideals I’m spouting. But I’ll try. The more of you who try, the more we will all succeed.

And by all means, buy Zoë Quinn’s book Crash Override and read it. Perhaps she too is a “mahatma” — a great soul.

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44 responses to “Crash Override

  1. Personally, I don’t consider you as particularly snarky as bloggers go – nowhere in the top 100. For some good snark, I read “Betty Cracker” at “Balloon Juice” (about Trump). I come here for factual analysis. I can’t think of any memorable snark phrases I’ve read here, but the analysis of “the Pause” with trend line and variation lines extrapolated from 1998, versus flat trend and variation lines starting at 1998 – that I will never forget.

  2. “I doubt I’ll be able to live up to the lofty ideals I’m spouting. But I’ll try. The more of you who try, the more we will all succeed.”

    Keep spouting!! The things that you said in this post are what we all need to hear repeatedly, no matter how many times that turns out to be. We definitely should all do more constructive rather than destructive things. As amazing as Gandhi was, he was still just another human as we all are. I too have seen that movie many times and am always impressed with how he was able to overcome the typical human faults to do atypical and amazing things for his fellow humans and set an example that we would all do well to emulate, at least as well as we can. To some degree or another, we all have an inclination to be snarky when we feel we’re right and that another is dead wrong. But we should all take a step back and look further at what the snark might or might not do and decide if it’s really worth being snarky or just state the facts as we know and understand them and try not to sound self-righteous while doing it. We all definitely need more of that!!

  3. The probability of snarkiness is, in my experience, proportional to a fatigue factor. My hardest choices and inner conflicts these days concern how much time I should devote to that I love, which is applying statistics, principally state space methods, to series of import, like hydrological ones, versus continuing to master Massachusetts energy policy and use it in discussions and lobbying to move things forward, versus working at social action projects at my UU church, including climate justice, and recognizing the structural racism in our community and even in my own language, versus keeping up with climate science and things on that front.

    To quote Elrond:

    Gandalf, the enemy is moving. Sauron’s forces are massing in the east — his eye is fixed on Rivendell. And Saruman you tell me has betrayed us. Our list of allies grows thin.

    [Response: I think we need to be careful who we put into the category of “the enemy.” Quinn’s wisdom on that point in particular, might be the most valuable part of her work.]

  4. Welcome back
    Missing your posts tamino I recently read some of your back catalog at SK SC.
    The wheel turns right around.
    The comments at SK SC are also interesting.
    Please don’t lose all the well crafted snark. Its the trend stupid was one of your best post IMHO.
    Glints of such humor make your contribution amusing , your comments rise above what is often a dry subject of statistical analyse and reveal the personalty behind the facade.

  5. Harry Twinotter

    Gamergate was complicated, and there are many sides to that story and plenty of blame to go around, in my opinion. But I do think the majority of the Gamergate online abuse came from trolls who do it for pleasure. And it is clear a lot of them target women.

    [Response: I think, you couldn’t be more wrong about gamergate. There aren’t “many sides” to bombarding someone with detailed accounts of how you’re going to rape them while murdering them, all based on accusations that are just plain lies, and targeting their friends and family, any more than there are “some very fine people” participating in a neo-nazi march.

    I suggest that you yourself buy and read that book. I insist that you not mention gamergate here again, until you have done so.]

    In my experience the majority of the climate change deniers are either just trolls, or third-rate journalists with a financial incentive to write nonsense, or a financial incentive to misinform – I think it is really that simple. As for Anthony Watts he is vicious and irrational, I have no idea what his motivations are I do not know enough psychology.

    I have encountered an minority who genuinely believe AGW is a hoax or a conspiracy. My guess it is some sort of projection from a pre-existing mindset or view about the world. These people can be scary; they are the ones who tend to get personal.

    As to people who in good faith think AGW is wrong on scientific grounds I am yet to encounter any! If anyone knows of any, give me a link or reference as I am interesting in reading what they have to say.

    • “As to people who in good faith think AGW is wrong on scientific grounds I am yet to encounter any!”

      How about Euan Mearns of Energy Matters, who is not persuaded that CO2 controls temperatures (or at least did not do so over previous glaciations), but states this case in scientific terms: It’s actually a very interesting post, and I do not know how to reconcile it with accepted climate science. I accept the science so assume that either there is something wrong, or that it doesn’t actually contradict current thinking, as claimed, but I’d like to see someone explain convincingly why.

      “Figure 1 shows one of the summary charts from my earlier post [1]. What we see are large cyclical swings in temperature of over 10˚C and by adjusting the scale appropriately, we see similar cyclical swings in CO2 concentration. But what is the cause and what is the effect? Does change in temperature and ice cover cause CO2 to change or does changing CO2 cause temperature to change? The climate science community has adopted the latter into their narrative, where very weak orbital factors trigger the cycles that are then amplified by changing CO2 and methane. This post will demonstrate beyond reasonable doubt that this part of the climate science narrative is untenable and should be dropped.”

      • Mearns is either being dim or disingenuous. No one is saying that CO2 caused the last several glacial cycles. The cause of that is well understood–Milankovitch cycles coupled with a large proportion of land masses in the northern hemisphere. Also, he clearly has not reached out to any professionals in the field, and there are no comments from such on his board.
        His logical fallacy is contending that if A causes B, then only A can cause B.

        As to gamergate, sorry, but I’m not going to stop to consider the finer points of a faction whose main argument seems to be threatening women with rape. They’ve ceased to merit consideration as humans.

        [Response: I quite agree about gamergate, but this post (and blog) aren’t about that, so let’s please leave such discussions for more appropriate venues.]

      • I’ve had occasion to look at 2 Mearns posts, one concerning wind energy in Europe, and one concerning the drought in Syria. In neither case did the data he cited come close to adequately supporting his conclusions. I doubt that he is operating in good faith, based on the gap between apparent skill and actual rigor; but perhaps it’s another sad D-K case, of the type in which real ability is sabotaged by equally real, but much more monumental, hubris.

      • Wookey — the basic fallacy with the “temperature precedes CO2 rise” argument is that it assumes causation can never go the other way–which has never been demonstrated. In a natural deglaciation, CO2 does indeed follow temperature, with an 800 year average lag (I don’t know where the 14,000 figure came from). But in the present warming, CO2 and temp. are rising in the same year, to a very high correlation. And statistics have to give way to physical causation–CO2 is a greenhouse gas, something demonstrated in the laboratory as early as 1858. There’s no getting around that.

      • Harry Twinotter


        I meant good faith rejection of AGW due to a preponderance of evidence, not just a single perceived “anomaly”.

        The “anomaly” itself is not considered unusual from what I have read. Actually it is expected, so it is a bit of a non-event. Also someone considering a temperature/CO2 response from a single location is going to miss the bigger picture.

      • I don’t seem able to reply directly (no ‘reply’ button on the posts), so attempting a collective one:
        snarkrates:. “His logical fallacy is contending that if A causes B, then only A can cause B.”.
        BPL: “In a natural deglaciation, CO2 does indeed follow temperature, with an 800 year average lag”

        His point is a bit more subtle than that. It’s not about the 800yr thing, which is explained by diffusion (Parrenin 2013), it’s about the much longer (14000 yr) delay between temp falling and CO2 changing at the Eemian glacial inception. (The graphs/text are clear about where that number comes from if you read it BPL). The standard theory (AIUI) is that a small Milankovitch change starts the cooling, then CO2 follows and amplifies, but that’s clearly not what happened on this occasion. CO2 didn’t move till the temp fall was almost complete. So the question is what did drive the temp fall? He then goes on to use this anomaly to cast doubt, on the grounds of ‘well if this explanation is wrong/oversimplified, what else are they wrong about’, which I agree is pretty silly given that it’s not the same case as now and we have plenty of contemporary evidence of what’s going on. But it does seem to me that there is evidence there for some other mechansim operating, and it would be good to understand what that is.

        Harry: “The “anomaly” itself is not considered unusual from what I have read. Actually it is expected, so it is a bit of a non-event. ”

        Well, OK, but I’ve not seen a clear explanation for this behaviour, and there certainly isn’t one in the comments on that blog. The case is well-enough made (unlike the usual nonsense we see on WUWT) that I feel it deserves a response from someone who understands this stuff, (or an admission that it is a bit of a mystery). Leaving it unanswered provides fodder for less scrupulous denial.

        I agree that it’s only one site, so maybe that’s why it seems anomalous. But it doesn’t take 14,000 years for CO2 levels to equalise around the world, nor corresponding temp changes to propogate (SFAIK), so what exactly is going on?

        I’ve read quite a lot of Mearn’s stuff, and whilst I agree that his biases are often on show (and those of many of his commenters are plain embarassing), I find his analysis is generally pretty good, and he really does try to use data to determine things, rather than just taking accepted wisdom. That’s good – that’s scientific, and genuine skepticism. I don’t think he is operating in bad faith, although obviously that’s possible.

        I don’t want to over-egg this post. After all he’s not published a paper, just blogged, but I do think that simply dismissing it as the ramblings of deniers is unhelpful, and responding in good faith, (with some expertise) as espoused by Tamino above, would be helpful in this case.

        “I meant good faith rejection of AGW due to a preponderance of evidence, not just a single perceived “anomaly”.”

        Well unless someone writes a book you don’t know what particular evidence they have looked at. Michael Kelly, an Engineer at Cambridge and member of the Royal Society is someone who might fit your bill. He’s a smart guy, but remains very skeptical about AGW. I must admit that I’m not sure exactly which things he does and doesn’t accept, but he is certainly a lukewarmer. Last time I argued with him (exactly 2 years ago) he was still insisting that the rate of temp rise had declined, and I was pointing him to Tamino posts illustrating that there was no evidence of that. He said he’d stopped reading Tamino for the same reasons I’d stopped reading WUWT “lack of credibility and reaching out”. Which I guess nicely illustrates the issue of talking past each other and reading sources we know we’ll agree with, and thus people see a very biased ‘preponderance of evidence’. (This is part of the reason I read Mearns, as it’s the sane end of skepticism/denial, so injecting some sanity into the comments there helps reduce the group-think).

        I’m sure he(Kelly)’s genuine in his belief that the rest of us are getting it wrong, and is a good illustration of the point that smart people are better at the mental gymnastics required to stay persuaded of an increasingly untenable position.

      • @Wookey,

        If I wanted to construct a straw man argument for being a Luke Warmer, I would argue that there is something about our understanding oceanic uptake of excess heat which underestimates how much it’s capable of dissipating or holding without the need to radiate in some way back into space. I’d go and study eddies, and then smaller eddies than the alive one week sort, and then smaller eddies of those. These also exist in atmosphere but atmosphere doesn’t hold heat as much as water.

        And I would argue that these eddies on eddies are essentially fractal and, so, in the form of dissipating motion, can hold great amounts of excess energy not in the form of thermal motion.

        This is, of course, completely made up, and I have no evidence for it, except the fact that eddies are notoriously complicated, are barely understood, and Who Knows?. That’s a little bit like the God Of The Gaps thesis in Creationism.

      • Harry Twinotter


        I cannot see the “14000 year” lag referred to. I am not just going to trust a crudely-drawn graph at those resolutions to show fine detail. The graph actually shows CO2 leading temperature, but again I would hesitate to trust it to show fine detail. Also it is not even global temperature which I pointed out before.

        Also I do not see any analysis of water vapor – just an observation. Rising and falling solar insolation due to orbital forcing is amplified by water vapor as well as CO2 and methane.

        Anyway if Euan Mearns wants to be taken seriously he needs to publish in a credible peer-reviewed scientific journal.

      • Harry: Time goes (unconventionally) right to left (limitation of excel, presumably combined with an inability to use R) in Fig1, so CO2 lags. You can see the detail on the zoomed-in Fig2.

        Good point about water vapour, and yes he should publish a paper if he thinks he has something, but I’d like to think that someone could explain why there isn’t much point.

        I guess we have done this to death now ;-)

    • Harry Twinotter


      I read the reviews for Crash Override a while back and decided not to read it as it only appears to cover Gamergate from one point of view. Gamergate was more a stuff-up of the Gaming media as much as anything else, it’s odd for the media to attack it’s own audience. Anyway there is a time and a place, and this blog is not it.

      [Response: You are 100% wrong, and your comments are 100% offensive. You can take it elsewhere, or drop it, but if you mention it here again you will be banned permanently.]

  6. I long ago realised that being aggressive and insulting does not help one’s argument. Leave that to “the other side”. I’m sure I don’t always manage it (a person can only take so much) but there is certainly no chance of convincing someone by insulting them, so I do my best to at least be civil.

    • I try to keep that as my default. Even if you are in conversation with someone completely stuck in denial, I think you are more likely to persuade 3rd party readers with civility than with insult. (And let’s face it, insult is pretty boring if you’re a 3rd party reader, unless it’s done with Shakespearian virtuosity.)

      I think there can be times for blunt frankness, but if you are going to say to someone that they are, for example, in deep fear-based denial, there’s no added value in calling them (again for example) a “lying, cowardly bag of dung.” In fact, that detracts from your point.

      Similarly, the point of snark, IMO, is that it’s surprising and thus funny. Thereby, it provokes thought even as it entertains. There may well be a personal element, but that should be secondary. It should be about the idea, not the person–even if that implies a rebuke to the one holding said idea.

  7. I’m really glad you read that and wrote this. It’s been a point of interest (and dismay) for me in the debates over the last decade I’ve been involved. I’d like to add to what you’ve read, and for others interested, with some personal anecdotes – or rather generalizations of anecdotes.

    I’m generally aligned with the mainstream view – not much I can do differently when seeking expert advice against my own abject lack of qualifications on the general and various topics. I’m not a climate change activist as such. I don’t advocate. I’m just keenly interested in science. My raison de participation is not to defend the world, or civilization, but to defend science. And that means being rigorous, not just cheer-leading. Rigour, objectivity, skepticism and intellectual honesty are currencies of scientific inquiry, so I feel I have to trade in these values if I’m going to defend it. I can’t allow myself to be partial or I’d be a hypocrite.

    (I realize the potential pitfalls of defending something to which I’m a relative novice. And also of neutralizing myself to the point of complacency)

    On occasion I’ve questioned articles at SkS and other blogs of that ilk, sometimes saying that a view overemphasised certainty or underemphasised uncertainty, or that the view strayed from neutrality into advocacy. And sometimes I’ve just disagreed. Not often, I don’t participate too much.

    Sometimes the regulars have labeled me a denier, and I experienced what it was like to be on that end of the stick. It is hugely off-putting, and rarely illuminating – even though I am a ‘friendly’ and quite open to honest exchange. At the same time, I don’t always express myself effectively, and the wrong emphasis here and there has set the avalanche in motion. But the point is, I have to tread carefully if I express dissent.

    Sometimes I’ve remark on what was happening and been called a ‘concern troll’. I’m expecting it even now. Because if I’m not perceived to be aligned, or not aligned in the right way, then this is a handy bit of net jargon to isolate and belittle the (seeming) outsider and protect the group. There are other net terms that are shortcuts to saying ‘piss off’. It’s like slang for the cool kids. Blunt instruments for discourse, but effective for the purpose.

    I’ve seen what I thought were genuine randoms dropping by being raked by the locals. Taking potshots in the trenches had conditioned them to continue sniping if a participant seemed to wear the wrong uniform. I’d think: if this conversation matters outside winning the skirmish, then you just lost a potential ally. And what about the optics for lurkers? Sometimes I’d ask what they wanted to achieve. (I did just yesterday at another climate blog)

    This is the point I always come back to if I muse about the way the stoush goes on.

    What is the objective?

    My guess is that people often lose sight of what their objective is in all this conversation, if ever they have articulated it to themselves clearly. So they got lost in a battle regardless of whether it would win them the war.

    You’re clear on what you’re fighting for, Tamino. That’s to your advantage as long as you don’t lose sight of it. Not everyone else has that clarity.

    That may be why I’ve read pretty much every post here. Clarity is compelling.

    Unfortunately, so is the stoush. Hard not to get dragged in. And then the environment is no better than any other on the net and the shine rapidly wears off for drop-ins. If outreach is important (and it doesn’t have to be) the opponent that gets you to lower the tone has an easy win.

    Maintaining the higher ground is bloody difficult. But there are those who manage it most, if not all the time. Nick Stokes and Zeke Hausfather readily come to mind. They’ve been good role models for me for when I participate at skeptic places – which is where I do most of my talking in these debates.


    I can’t remember anyone ever doing a guest post. Might be good to shift the paradigm a little and share your space with other bright minds. Don’t know if it would suit your vision for Open Mind, but I can think of a bunch of good corollaries. Nick and Zeke would make great guests.

  8. I enjoy the snark here, but it does mean that I have to choose your posts carefully if I am posting a link to refute some anti-climate-change point. People in denial are likely to get as far as the first bit of snark and stop reading. This is unfortunate because you have some really excellent explanations of various issues.

    It’s important to keep some humour, and sometimes you just have to take the piss out of the ridiculous things people post, but as a purveyor of excellent rebuttals, bear in mind that you will have some very skeptical readers, and we _do_ want those people to read and understand.

  9. I enjoy being a bit snarky. Its probably better to try and win arguments logically, but I’m not sure. Sometimes its more fun to just stick the knife in.

    And it is also tricky when your own side comes up with silly arguments, or dismisses ideas out of hand.

    For example, I’ve often wondered if the fairly dramatic increase in agricultural productivity in the 20th century wasn’t due, at least in part, to increased concentrations of CO2 in the atmosphere. Now I may be wrong, but this idea too often seems to be dismissed out of hand – because there can’t be anything good about extra CO2.

    Of course its obvious that on the whole pumping vast amounts of CO2 into the atmosphere is a dangerous experiment with consequences that are already abundantly clear and that only crazy people would want to continue the experiment.

    Oh, and even if you prove that CO2 levels haven’t increased agricultural productivity, I’m still going to believe that they make the weeds in my garden grow faster…

    • Sai Brooks–I’ve run that regression. There seems to be a link between CO2 and ag productivity, until you add fertilizer use as an independent variable–then the CO2 term drops out.

      • During my lifetime (as a child I watched Gramps plow the cornfield with a mule team): longer growing season; herbicides; pesticides; fertilizers; major equipment improvements; major seed improvements; soil management improvements, etc.

      • But you could do the regression between fertilizer and ag productivity, and then when you add in CO2, the fertilizer term might drop out?
        This particular sort of statistical analysis does my head in – just how do you sensibly look at contributing factors?
        I once tried to do this to see how a university physics mark (X) depended on high school maths (A). There was a fairly strong linear relationship, and you could write X = a A + z0 , where a had a value of about 0.8 (say). I expected this. But then I added the high school physics mark (B) and the high school specialist maths mark (C) into the analysis. So now for a linear best fit I could write X = a A + b B + c C + z0. But now the coefficient “a” for A is actually negative and small.
        So what do I conclude? Is X fairly strongly dependent on A and positively correlated, or is X negatively and weakly correlated with A?

      • @John Brookes,

        Y’either nees to calculate a proper Bayesian posterior for these or account for overfitting using something like AICc or WAIC.

        – Jan

    • There’s Ruddiman’s “early anthropogenic influence hypothesis”:

      The thing about CO2 being “good” in this case is that then it kind of undermines that argument about future warming being “good” in my mind. We already had the “good” warming, and we’re now facing orders of magnitude more warming.

    • @John Brookes:
      Global plant photosynthesis is expected to have increased by about 15% since pre-industrial values due to the increased atmospheric CO2 levels, which is consistent with observations, although with large uncertainty in both directions.
      The expected increase is about 10% since 1960.

      This is a benefit from the CO2 emissions, and it should be weighted against the damage from climate chance.

      The agricultural yield increase since 1960 due to the increased atmospheric CO2 levels will be similar, about 10%.
      The total agricultural yield increase since 1960 is far larger, more a factor of two, three or more. And it was mainly due other factors as fertilizers and others.

      • @ULI,

        The quoted assessment of improved growth is incomplete. Plants also respire, and they need water and nutrients, too.

        Schlenker and Roberts reported in 2009 that growth yields for corn, soybeans, and cotton increase up to ambient temperatures of 29 ◦C,
        30 ◦C, and 32 ◦C, respectively, but “. . . that temperatures above
        these thresholds are very harmful”.

        And since we are on the subject of food, N. R. St-Pierre, B. Cobanov, and G. Schnitkey reported in 2003 on economic losses for agriculture due to heat stress in herds.

        And, as the most recent issue of Frontiers in Ecology and the Environment highlights, not only is ocean acidification a threat to the global reliance on marine protein, but ocean deoxygenation is a worse and underestimated threat. (See Schmidtko, et al 2017; Nature 542: 335-339.) Neither of these problems can be parried or addressed by quick-fix solutions like solar radiation management.

      • @hypergeometric:
        I’ve not tried to give a complete assessment, because it would be very long, and many aspects are still not known.

        I only tried to answer John Brookes’ question about the influence of atmospheric CO2 levels on (land) agricultural productivity.

        From the approximately increase of yield of 2% per year since 1960 about 0.17% per year is due CO2 increase if agriculture behaviour is similar as the global land biosphere. This is less than a tenth, not negligible, but not a mayor contributor to agricultural productivity.

        The impact of the temperature increase up to now on global plant photosynthesis and agricultural productivity is, as far as I know, in global average likely negative but yet small *, because the pre-industrial temperature may close to or slightly above the global optimal growing temperature. The regional difference are likely large.
        The impact on ocean live may more negative then on land.
        But all this needs further research.

        For an overview I would suggest the IPCC AR5.

        Solar radiation management is an other topic, different from John Brookes’ question. I think SRM is a bad idea because of reduction of precipitation and possible disruption of the hydrological cycle, and the negative impact on the solar energy.

        *) The best estimate may a decrease of global land plant photosynthesis of about 3% due the temperature increase up to now since pre industrial, but the error are large and there may be other not considered influences.

      • @Uli,

        I have just reviewed the entirety of the AR5 full document looking for discussion of either plant productivity, agricultural productivity, net primary productivity, or global primary productivity. AR5 does not discuss elevated CO2 effects upon agricultural productivity much, although it does spend a lot of time discussing possible effects on oceanic primary productivity, and there is a mention of effects upon global primary productivity, with some emphasis upon the productivity of temperate forests. This is from the Physical Science Basis.

        However, using the key authors cited in the AR5 literature, intersected with the reference author names from Schlenker and Roberts gives a glimpse if not a synopsis of the state of the literature. In fact, early assessments of effects of CO2 on crop yields from 20 or more years ago suffered experimental problems, both in the application of CO2, control of ozone concentration, and in the experimental design. More recent experiments, more carefully done, gave less optimistic results. Apparently, the consensus on agricultural productivity (using maize and soybeans as model crops) remains as Schlenker and Roberts report: A nonlinear effect, with an initial improvement with increasing CO2, but then a crash as temperatures warm concurrently. The other key authors are Zak, Leakey, and Burton, among others. This is apparently true even if crops are not affected by drought. The assessment of temperate forest productivity is more sanguine, assuming O3 concentrations don’t skyrocket, as they might under SRM. But the 2014 consensus is that not enough is known about stability of newly placed Carbon in forest soils to understand the final impact upon the Carbon budget. These results do in part depend upon long term experiments with enclosed forests, and, for example, the relationship among CO2 and O3 have been assessed with factorial designs (Talhelm, et al, 2014).

        Accordingly, I disagree with your characterization that there are benefits from agricultural or forest productivity from elevated CO2 levels, based upon my review, and especially with the finding by Baccini, et al, 2017, that tropical forests are a net Carbon source. Moreover, acidification, deoxygenation, and temperature increases suggest impairment of gross productivity in oceans, and, as these are important contributors, it’s not clear the gain is worth the loss (Heinze, et al, 2015). Sure, temperature forests appear to increase the amplitude of annual modulation on the Keeling Curve (Graven, et al, 2013).

        An aside:
        I found what looked to be a relevant report from 2011, The Food Gap: Impacts of Climate Change on Food Production: A 2020 Perspective, where the results are based upon AR4, not AR5. It turns out this report produced a firestorm in the usual media, resulting in a pushback from Dr Gavin Schmidt and others. The offending paragraph of the report appears to be:

        Carbon dioxide (CO2) is the most important man-made greenhouse gas. In 2008, CO2 levels reached 385.2 parts per million (ppm). With current increase rates of about 0.5 percent per year, CO2 levels could reach 410 ppm in the next decade. [We are essentially there.] These levels correspond to greenhouse gases (GHGs) concentrations above 490 ppm CO2-equivalent (all greenhouse gases combined). This equals a [latent] 2.4ºC increase in global temperature above pre-industrial times.

        (I’ve added clarifications and comments in square brackets to the text.)

        Instantaneous values of atmospheric concentrations of CO2 depend upon how one counts. In particular, if CO2-to-come sources are counted, such as methane, all these being sometimes called CO2e, then one gets the 490 ppm. Similarly, and what was not stated in the report and should have been, the 2.4ºC warming is committed warming, that is warming which is implied by the atmospheric concentration but has not yet been realized, due to lags.

      • A couple other papers might be relevant to food production and grassland biosystems as climate changes:

        A. J. Challinor, A.-K. Koehler, J. Ramirez-Villegas, S. Whitfield and B. Das, “Current warming will reduce yields unless maize breeding and seed systems adapt immediately,” June 2016, DOI: 10.1038/NCLIMATE30 (

        “Increases in mean temperature accelerate crop development, resulting in shorter crop durations and reduced time to accumulate biomass and yield. The process of breeding, delivery and adoption (BDA) of new maize varieties can take up to 30 years. Here, we assess for the first time the implications of warming during the BDA process by using five bias-corrected global climate models and four representative concentration pathways with realistic scenarios of maize BDA times in Africa. The results show that the projected dierence in temperature between the start and end of the maize BDA cycle results in shorter crop durations that are outside current variability. Both adaptation and mitigation can reduce duration loss.”

        F. Alice Cang, Ashley A. Wilson and John J. Wiens, “Climate change is projected to outpace rates of niche change in grasses,” September 2016, DOI: 0.1098/rsbl.2016.0368 (

        “Grasses are fundamental to one of Earth’s most widespread biomes (grasslands), and provide roughly half of all calories consumed by humans (including wheat, rice, corn and sorghum). We estimate rates of climatic niche change in 236 species and compare these with rates of projected climate change by 2070. Our results show that projected climate change is consistently faster than rates of niche change in grasses, typically by more than 5000-fold for temperature-related variables.”

  10. I have had very little interaction with trolls. In one case, I was able to deal with a cousin of a friend who was adamantly anti-climate change. In the course of three email exchanges over a six month period, I converted him to a position of thinking that there might be something to climate change and wanting to learn more.

    Another instance that occurred intermittently over a few months involved a climate change Facebook discussion group with several thousand members. I had a friend B. in the group from Germany who had worked on the SkS site and was quite knowledgeable. There was a troll R. in the group who would attack B. with links to sites like friend Anthony Watt’s site. This could turn into a long sequence of B. R. B. R. …, which I considered unproductive. I would intervene with several comments in a row directed at B. with links to additional relevant arguments and peer-reviewed papers that should be considered. B. would respond to me with more links, and I would answer with more development. Typically, the troll would quickly disappear because nobody was responding to him.

    But mostly I ignore trolls and antis. I am more considered with people who have no position and moving them to possibly interested, with people who are possibly interested and moving them to a little concerned, with people who are a little concerned and moving them to very concerned, and with people who are very concerned and moving them to take actions to change the situation.

  11. Good post. This discusses somthing that has long bothered me; the capacity for feeling okay and even pleased about others being hurt – as long as you (we, I) think they deserve it. It does look to be a universal human trait.

    How much satisfaction with a crime drama comes with from seeing the ‘bad guy’ get gut punched or sex offender being put in the same cell as a brutal rapist whilst awaiting trial? Not examples I’ve made up – but of course in the story you KNOW they are guilty – which sets us up to feel what we are expected to feel. But we don’t even need to know – this works with no need for an investigation and trial first; just being told they are bad can be enough. Just being of a particular nationality, ethnicity or religion and being told that those are bad can be enough.

    Truly this is one of humankinds most dangerous traits and we need raise people to understand it and be able to recognise it – recognise and resist in ourselves and in others.

    [Response: I think you’ve hit the nail on the head.

    I grew up believing the right response to bad people was what I call “John Wayne.” Stand up and fight for what’s right, and be prepared to kick some serious ass. Gandhi made me aware of the question, “Do you fight to punish, or do you fight to change things?” When we overcome our powerful instinct to punish, we re so much more able to change things for the better.]

    • Ken Fabian,
      It is deeper than “human”. It seems to be present in most social primates and perhaps most social mammals. Primates take pleasure in the misfortune and even the physical pain of an individual perceived as “bad”. In the case of humans we have the additional issue of having the anonymous intertubes where we can revel in the misfortune of others without fear of being identified, ourselves, as bad. I suspect that getting rid of anonymity in a forum would go a long way toward restoring civility.

      • I suspect that getting rid of anonymity in a forum would go a long way toward restoring civility.

        I thought this too, but it was recently explained to me that this is a belief of people in priviledged/majority groups, who will not have anything bad happen to them if they are identified for their speech. People in minorities, or who are powerless are _less_ likely to speak in such circumstances, because they may be victimised (or worry that they might be). It was made by the guy who set social policy at Google+ for some years. He made a lot of interesting points. (sorry can’t find the link right now)

      • FWIW, it seems to be hard to enforce, too. CBC.CA tried that, with the result that the rabid (and immensely stupid) denialist whose handle used to be “Tim’s Rant” now goes by “Tim S. Rant” (or some such.) Now they mostly don’t allow commenting on climate-related stories, which is an improvement from the days before I and numerous other folk started systematically debating the denialists, who had originally dominated the threads.

      • PZ Myers has had good luck sending comments from particular IT addresses to the spam netherworld. Trolls do get around it, but the flux of trolls is greatly reduced. Most trolls, as it turns out, are lazy as well as nasty.

      • @snarkrates,

        Yes, doing that is entirely feasible, but it helps if you are running WordPress or whatever on your own server, or one you rent, so you can use Apache rewrite rules.

        I don’t know, for example, what the public WordPress I use to host my blog, as an example, offers for this kind of thing. Fortunately, I’m not popular enough to have that kind of problem. I think I’ve only blocked a poster once.

  12. JB: But you could do the regression between fertilizer and ag productivity, and then when you add in CO2, the fertilizer term might drop out?

    BPL: No, it doesn’t work that way. When you do it with both, the fertilizer term is statistically significant (by t and partial-F test) and the CO2 term is not.

  13. Here’s a tutorial on basic statistics I put up a few months ago:

  14. ATTP has a post up on Civility which addresses some of the same concerns.
    Ken Fabian, above makes as you said a very good point. Also applicable to our behaviour when watching our sporting teams where we value aggression in our team and deplore it in the other.
    I admire your questioning of behaviour, very hard to do and very hard to see in ourselves.
    One of the problems with “personal” attacks and responses done early in our careers is that bitter taste that develops and will probably stop most of us from what could have been good discussions, or shock, horror, friendships. Often seen when we see family members falling out.
    You and Anthony get the heavy end of the stick being so vocal and obvious.
    Both of you carry the weight of a lot of personal invective [I have been guilty in the past in your case].
    Thank you for asking people to cut him some slack. I doubt it will convince most warriors but if he reads it he might cut you a little slack back. You never know.
    Thanks for this and some of your other posts in this field in the last two years.

    • @angech,

      Also applicable to our behaviour when watching our sporting teams where we value aggression in our team and deplore it in the other.

      That’s an interesting point, and, to the topic at hand, worth remarking on. When I first attended a Chelsea football match in London, I was shocked at the amount of partisanship each team’s fans exhibited. Indeed, sitting among diehard Chelsea fans, when I expressed some support for a ref call against one of the Chelsea players, I got looks. I realized I needed to keep quiet.

      Of course, this is a sport when the bobbies regularly take to horseback pre- and post-game, and cordon off fans of the opposing team with a line of officers.

  15. Some free advice from a snarky commenter, for whatever it’s worth: if it involves a neutrally worded question or comment, assume good faith for the first interaction or two, even if it’s about something that has been dealt with many times before.

    But keep an eye open for timewasters, trolls, sea lions and JustAskingQuestioners, and if and when it becomes clear that this is what they are, be firm. Your time is more valuable than theirs, and as has been long noted, it takes at least an order of magnitude more work to refute BS than to generate it. And knowledgeable readers don’t gain much from seeing “why don’t climate scientists consider the sun?” debunked for the millionth time.