Beware the Werewolves, Part One

It was recently brought to my attention people are seriously underprepared for the risk of werewolf attacks when a user tweeted to me:

Prior to this tweet, I hadn't really done a risk assessment of werewolf attacks. You see, I always figured werewolfs aren't real, so the damages I should expect from a werewolf attack were 0. That's zero dollars (0 D), zero human lives (0 H), zero everything.

But then it occurred to me, what if there's one werewolf somewhere in the world? I don't think there is, but how could I ever completely rule out the idea? I can't. I have to accept there is some theoretical amount of uncertainty about that possibility, meaning there could be a werewolf attack at any time. Tens of thousands of dollars and half a dozen lives could be lost.

Humans could probably handle one werewolf. Even if it managed to infect a couple victims, it wouldn't be that hard to handle a single threat. There'd be entire militaries and scientific organizations that could be devoted to hunting down that one werewolf.

But what if there were five? Or ten? The more werewolfs there are, the harder it would be to contain any one of them as there'd be fewer resources to devote to each. Each additional werewolf would make the problem worse, and given enough of them, there'd be no way to contain them all before they could manage to infect the entire world.

That's really scary, right? The danger posed by werewolfs increases faster with each additional werewolf. It's like an exponential curve, quickly shooting off into nowhere to indicate the doom of the human race as we know it.

You might wonder why I'm talking about this. Normally I wouldn't even think about it. I only did today because it turns out global warming advocates want us to create military organizations to prepare for the potential onslaught of a werewolf horde, and I think we should all support them.

Okay, let's be honest. No global warming advocate (that I know of) has actually talked about werewolfs. I'm just applying the argument some of those advocates use to a different topic to show how ridiculous it is. There's a formal name for doing this: argument ad absurdum. It's where you take a person's argument to its logical conclusion to show it reaches conclusions that are absurd.

In this case, I'm examining an argument which has strong ties to Pascal's Wager. For those who don't know, Pascal's Wager said it is best to act as though the Christian God exists because the punishment of eternal suffering in hell far outweighed any costs of doing so. In other words, it's not that you believe God is real. You just can't be sure he isn't real, so you should act as though he is just in case. The parallels to the werewolf situation should be obvious, but what's more interesting is an argument the blogger Victor Venema, who sometimes visits here, says that resembles Pascal's Wager in form. He recently wrote a post which begins:

Imagine you are driving on a curvy forest road and it gets more foggy. Do you slow down or do you keep your foot on the pedal? More fog means more uncertainty, means less predictability, means that you see the deer in your headlights later. Climate change mitigations sceptics like talking about uncertainty. They seem to see this as a reason to keep the foot op the pedal.

While this is madness, psychology suggests that this is an effective political strategy.

I would like to think anyone could see through this obvious strawman. It turns out that's not the case. Venema really does seem to believe it is reasonable to conflate the position of global warming skeptics on uncertainty with "keep[ing] the foot op the pedal" when one sees fog. I don't have words for how stupid that is so I'll just move on to where he says:

Maybe people do not realise that uncertainty can have multiple meanings. In case of climate change "uncertainty" does not mean that scientists are not sure.

Yes, he actually does say this. I'm not complaining about the second sentence here, though I do think it's a horrible way to express his intended meaning. He goes on to explain uncertainty in this case means scientists are "sure" about some things and not "sure" about other things, but...

Seriously, what the... Venema draws attention to the fact "uncertainty can have multiple meanings" right after giving an analogy where he portrays global warming skeptics as suffering from "madness" because of one meaning of uncertainty. Had he chosen a different meaning of uncertainty and built an analogy around that, global warming skeptics would have seemed like normal, sensible people. For instance:

Bob heard there was going to be a severe flood tomorrow. However, Bob also heard there was a great deal of uncertainty in this prediction. Because he accepted there was some potential risk, he took some steps to secure a few key possessions so they wouldn't be damaged if there was a flood, but he didn't do anything drastic like leave town.

Notice the difference. The uncertainty in this example was very different from the uncertainty in Victor Venema's. In this example, uncertainty did not increase the risk involved. Instead, it made acting like normal a more rational choice because uncertainty actually decreased the chances of harm. In Venema's example, uncertainty increased the chances so much acting like normal would likely be suicidal.

What this shows is Venema knew there were many potential meanings for "uncertainty" and intentionally chose the one which allowed him to paint the people he is criticizing as insane when he could have chosen any number of other meanings, including ones which would have painted them as perfectly sane and rational. That's not inherently wrong, but it shows the important question is, "Was Venema's example appropriate?"

The answer is "No, not at all." This is made clear by looking at what Venema goes on to say:

The damages of climate change rise with its magnitude (let's call this "temperature increase" for simplicity). I will argue in the next section that these damages rise faster than linear. If the relationship were linear, twice as much temperature increase would mean twice as much damages. Super-linear means that damages rise faster than that. Let us for this post assume that the damages are proportional to the square of the temperature increase. Any other super-linear relationship would show the same effect: that more uncertainty means higher risks.

In this case, if there were no uncertainty and the temperature in 2100 will increase by 4 degrees Celsius. For comparison, the temperature increase in 2100 is projected to be between 3 and 5.5°C for the worst scenario considered by the IPCC; RCP8.5. With 4 degrees warming the damages would be 16*D (42*D) dollar or 16*H human lives.

In the case with uncertainty, the temperature in 2100 would still increase by 4 degrees on average, but it could also be 3°C or 5°C. The damages for 4 degrees are still 16*D dollar. At 3 degrees the damage would be 9*D and at 5 degrees 25*D dollar, which is on average 17*D. The total damages will thus be higher than the 16*D dollar we had for the case without uncertainty.

The entire point of his argument is to say the dangers of uncertainty on one side (higher climate sensitivity) are greater than the benefits of uncertainty on the other side (lower climate sensitivity), meaning increased uncertainty increases the expected risk. Whether one accepts that argument or not, it clearly doesn't justify Venema's choice of analogy.

In Venema's choice of analogy, he painted global wawrming skeptics as insane because they wanted to drive through a fog bank as though the fog bank wasn't there. That was intended to portray skeptics as calling for "doing nothing" about global warming based on the idea uncertainty on both sides (higher and lower climate sensitivity) cancel one another out, and that is the same as driving through a fog bank without slowing down.

To be blunt, Venema either has to be incredibly closed-minded, incredibly stupid or incredibly dishonest to think that is an appropriate analogy. The uncertainty which comes with a fog bank does not have any benefits to one's ability to drive. The fog doesn't make anything easier to see. The fog doesn't make any obstacles easier to avoid. The fog doesn't do anything to reduce the dangers of driving. Uncertainty about how much warming there will be obviously does carry some upsides.

Part of me wants to dwell on this matter a lot more. It is ridiculously offensive Victor Venema would offer this analogy to portray people he disagrees with as crazy when it is completely inappropriate. I feel I should do more to emphasize that point. I just don't see going off on some rant with lots of harsh words and insults as adding anything. So as a favor, while you read this paragraph, please just take a moment and think about what Victor Venema did. He took a situation where he specifically said there were benefits and dangers posed by uncertainty then portrayed anyone who felt those two balance out as crazy people who would support recklessly driving through a fog bank... which could have no possible benefits.

I mean it, please take a little time to dwell on that. The full level of offensiveness that entails is beyond my meager ability with words to convey. I'd like you to try to work it out for yourself. Once you've done that, hopefully I'll have written the follow-up to this post. In that next post, I'll explain why Venema's post is even worse than I've indicated so far. I'll also explain why I discussed werewolfs at the start of this post, and how, perhaps, we should be forming an anti-extra-terrestial army instead of a military force to combat the werewolf horde.


  1. The original Palscals Wager is a false dichotomy to start with: What if you have chosen the wrong religion? Venema does a classic cutting out of the middle man.

  2. Yup. That is one of the many problems with his post. It's something I intend to discuss in the next post, which I'll hopefully have up in about 36 hours. I'm wanting to create some simple graphs for it, and the tablet I used to type this post isn't good for doing things like that.

    But as an example of what he gets wrong, notice how he only discusses the uncertainty in the magnitude of warming. This assumes the time component is irrelevant to the subject. Nothing could be further from the truth. For a simple point, the rate of warming greatly impacts any damages caused by any particular amount of warming. If we were certain there would be two degrees of warming, but didn't know if it would happen by 2050, 2100 or 2200, there would be a great deal of uncertainty in the damages we'd expect. That we know the total amount of warming wouldn't matter much.

    This becomes particularly relevant as we begin to examine more complex points. For instance, while the damages caused by warming grow faster than linear as the amount of warming increases, those same damages shrink faster than linear as the amount of time taken increases. Uncertainty in the temporal domain can have the exact opposite effect Victor Venema describes.

    And it can get even more complex when we begin to examine the value of testing our hypotheses. Taking aggressive action early to reduce the amount of warming that will happen will inherently make it more difficult to tell what the climate sensitivity truly is. Doing less to combat global warming will actually lead to us gaining more information. That could be quite valuable. Accounting for that factor could have who knows what effect on the results.

    Global warming advocates don't seem to want to look at the full picture. They keep resorting to these weak arguments that won't convince anyone except those who would likely agree anyway because everybody else will see there are many obvious problems with those arguments. I don't get it. If I thought global warming were a serious problem, I'd try to make sure I actually examined all the possibilities and made the best arguments possible.

    But anyway, that's a bit of a preview of what you can expect from my next post. I'll stop writing now so I don't just write the post here and now 😀

  3. MikeN, not at all. He says:

    The lower dashed lines mark two estimates of the 1960 value, and the upper dashed lines are 0.5C above those. For an honest definition of the “since 1960” value, we might use the smoothed value of -0.046 deg.C, or we can just use the 1960 average, -0.031 deg.C. They’re not that different.

    To define the present value, we can use the smoothed value of 0.75 deg.C, the 2015 annual average so far (based on the first 11 months of the year) of 0.845 deg.C, or the average of the most recent 12 months, 0.839 deg.C.

    Tamino cites the NASA GISS temperature set. Here is the data for a figure GISS provides which mostly matches his. The difference is the choice of smoothing they apply. GISS applies a simple 5-year rolling average. Tamino applies... I'm not entirely sure what, because he doesn't say. If I had to guess based on what I remember reading on his site in the past, I think it's a modified Loess smooth he custom-brewed. You'll note, however, Tamino never discusses what type of smoothing he used so a reader can't really know. They certainly can't be faulted for not using it themselves.

    Since a person looking at this matter can't be expected to use whatever smoothing Tamino used, it would be reasonable for them to use the one GISS itself presents. The values it provides are quite different from Tamino's. The smoothed 1960 value Tamino gives is -0.046 while the data file I linked to shows GISS giving its smoothed 1960 value as 0.03. That's a difference of ~0.08 in Lindzen's favor. Tamino gives the present smoothed value as 0.75 while GISS gives its most recent smoothed value as 0.67, again, a difference of ~0.08 in Lindzen's favor. So when Tamino says:

    Whichever honest choice you make, the warming since 1960 has been bigger than 0.5C. You could honestly say 0.8C, or 0.88C, or 0.87C. But you can’t say 0.5C without being either dishonest or astoundingly ignorant (or both).

    This is based largely upon a perosn using his particular choice of smoothing method, a choice he hasn't even disclosed. If people used the smoothed values given by NASA's GISS, they would find a warming since 1960 of only 0.64. That's closer to Richard Lindzen's stated value of 0.5 than it is to any of the values Tamino gives.

    A person might reasonably criticize Lindzen's stated value, but not in the way Tamino has done. GISS's own numbers pluasibly give a value of 0.6. One can say those numbers shouldn't be used because the choice a 5-year rolling average is a bad way to smooth data. One could argue some other approach to smoothing the data would be more appropriate, such as whatever way Tamino has used. What they can't do, if they want to be fair or reasonable, is ignore the fact the data source they cite gives numbers which largely support the person they're criticizing in order to use over-the-top rhetoric like Tamino has.

    By the way, GISS is only one source. If Tamino were remotely interested in fairness, he'd have looked at what GISS and the other groups publish on this matter. We've already seen GISS publishes numbers which make Lindzen's value "wrong" by 0.1 degree (as it should have been 0.6 instead of 0.5), but I have no idea what the other groups publish offhand.

  4. I actually had concluded .6 just by looking at Tamino's chart, 1960 is an outlier by about .1 and then .1 from using 2015 temperatures. Hadcrut I was surprised doesn't appear to give a lower difference, which I expected due to adjustments in GISS to SST.

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