I’ve written before about Matt Ridley’s recent article and posed some thoughts. Although I have a number of issues with what he suggests, my main one relates to how much warming he thinks we can expect by 2100. Matt Ridley selects a particular set of results that tend to produce lower estimates than other methods, selects a single value from these analyses, and then argues that we won’t see much warming by 2100. Even though this is possible, his own preferred method does not rule out that warming could be substantially higher than he suggests.
Now, most of what he relies on is work by Nic Lewis, an independent climate scientists. Nic Lewis commented here and responded to one of my comments on Mark Lynas’s blog. In neither case did he seem willing to acknowledge that his own work suggests that warming could be substantially more – by 2100 – than Matt Ridley suggests. Instead he decided to nitpick a few minor issues, rather than addressing the broader point. Why would that be? What am I missing? If you look at Table 5 in Lewis & Curry (2014), the 5 – 95% range for TCR is 0.9 – 2.5K. If you consider the basic equation for TCR, then you can write the temperature change 
So, a 5 – 95% range of 0.9 – 25K and an RCP6.0 emission pathway (
Now, Nic Lewis gets – and should get – a lot of credit for doing research and publishing papers. It’s what a real skeptic should do. However, he is an ex-financier with links to the Global Warming Policy Foundation. His work also tends to produce results that suggest that climate change may not be as much of an issue as we otherwise might think, and which is often used to make this argument. Consequently, it’s not surprising that some might think that what motivates Nic Lewis is his ideological objection to the policy implications associated with mainstream climate science, rather than an intrinsic interest in climate science itself. Now, this may be an entirely unfair interpretation of Nic Lewis’s motives but, if so, maybe he could put a bit of effort into ensuring that it isn’t the obvious one.
...and Then There's Physics 
I’m sick of Matt Ridley and Nic Lewis. I’m also not at all surprised that neither will acknowledge that warming might be higher than they’re suggesting or that they might be wrong.
Off-topic but big news is this:
US and China strike deal on carbon cuts in push for global climate change pact. This is an historic deal isn’t it?
Lewis’ contrarianism is clear, for example in his GWPF report in which he pooh-poohed every method to estimate climate sensitivity except his own, which just happens to be the only method that arrives at relatively low estimates. The mere fact that he contributes to GWPF also makes his contrarianism obvious.
As with most contrarians, it’s safe to assume that contrarianism stems from ideological biases.
Rachel,
I saw that. Thought of writing about that but Eli’s already done so.
Dana,
It is hard to conclude otherwise, but I do dislike making suggestions about someone’s motives. It’s just too close to what you commonly see on “skeptic” blogs and in the comments on such blogs. Sometimes it is hard not to do so, though. I’m waiting for Joshua to come along and point out the irony in my post 🙂
Rachel
I’ve had more than enough tactical science and political advocacy too.
As for the US-China deal, I have one deep misgiving, which is that the Republicans will tear down the US end and Xi Jinpeng will use this as an excuse to renege on the Chinese end. Worse, he may *expect* this to happen and simply be indulging in some clever international PR.
AndThen,
I didn’t mean my comment as a criticism of your post, btw. I think it’s good that you write about this stuff. I had a roll-my-eyes moment when I read it though and I could hear Joshua saying “same ol, same ol”.
BBD,
Ok, I was wondering what people thought of it. I’m a bit more optimistic about the Chinese side of the deal. I’m not sure why, perhaps it’s because they don’t seem to have the same denial machine there or maybe I’m just not aware of it. There’s also a good oped in the NYTimes from John Kerry-
Rachel,
So could I. I’m hoping he recognises the subtlety in what I’ve written 😉
BBD,
I wouldn’t be surprised if the US-China deal was essentially a failure, but it’s a step. I’m starting to think that some of our policy makers are not idiots and realise that climate change is a risk and that we should be doing something sooner rather than later. Someone – and this might be Obama’s motive – will want to be the statesperson who makes the first big move. This might not be it, but maybe this one will be the beginning of that kind of thing.
ATTP: Aren’t you being a bit generous when you state,
Now, Nic Lewis gets – and should get – a lot of credit for doing research and publishing papers.
“an independent climate scientist”
Anders, this is way, way, way too generous. It amounts to granting Lewis much of the propaganda victory he’s after. IIRC Nick Stokes e.g., who has done much more and more useful work than Lewis, doesn’t refer to himself as a climate scientist, nor does (the multiply-published) Grant Foster. If it’s a matter of publications, then I suppose you should follow RP Sr.’s lead and start referring to e.g. Watts and McIntyre as climate scientists. While it’s not helpful to have such people outside the tent pissing in, it’s even less so to try to move them inside to continue. Doing so amounts to making a suggestion about their motives.
The focus on Ridley and Lewis indeed has become tiresome. Yes, smart people will always be fascinated by how other smart people can screw up so badly, but the history books (and the news headlines) are filled with that sort of thing if you really want to indulge yourself. Bear in mind the difference between actually smart and merely clever, and that psychopaths tend to rise to positions of influence in our society.
Steve,
Yes, I wrote the indepedent climate scientist while thinking ironic thoughts, but didn’t get that across in the post. Yes, it is quite interesting that only one “side” of the debate will state what they are or aren’t – “I am a climate scientist”…”I’m not a denier”.
As to be expected…
Top Senate Republicans slam U.S.-China climate deal by Jeremy Diamond, CNN, Nov 12, 2014
JH,
No, I do think people should get credit for actually publishing in peer-reviewed journals. It is a common criticism of “skeptics” (i.e., if you think you’ve overturned decades worth of work, publish it”). It doesn’t, however, excuse poor behaviour elsewhere, though.
ATTP: There’s a big difference between “credit” and “lots of credit.”
JH,
Well, okay, that might be fair.
ATTP,
I suspect some of the confusion here stems from the assumption that RCP6.0 results in a 6 W/m^2 forcing change. It is an understandable assumption (as this is how they were originally named), but in practice, the CMIP5 forcing change in 2100 associated with RCP6.0 is actually much smaller – around 4.5 W/m^2. See, for example, figure 12.4 of AR5: http://www.ipcc.ch/report/graphics/images/Assessment%20Reports/AR5%20-%20WG1/Chapter%2012/Fig12-04.jpg
This obviously gets into issues of RF vs. ERF vs. ARF vs. BARF (the last one is not real 🙂 ), but using 4.5 W/m^2 for RCP6.0 would yield a range between 1.1K and 3.1 K using that simple method you describe.
BBD and Rachel, while Congress can engage in limited obstructive tactics, it’s the case that Obama already has (from prior Congresses) the legal authority he needs to do this. Note that he’s already under court order to do some of it (consequent to prior delays by both him and his predecessor) since laws like the Clean Air Act aren’t optional. To substantially interfere would take a veto-proof majority in both houses of Congress, which the Republicans lack, although they are likely to go through the exercise a number of times, maybe even taking it so far as shutting down the government over a veto of an attempt to wreck the EPA via a budget bill. Of course all of this will have implications for the 2016 elections, potentially major ones. We live in interesting times.
troyca
My understanding is that Ridley and Lewis are mitigation sceptics. They would see nothing substantive done. If so, then they cannot appeal to RCP anything except RCP8.0 since all the others explicitly include emissions reductions later this century.
Thanks Steve. I freely admit that the finer points of US policy and law are unfamiliar to me.
troy,
My laptop battery is about to die, but I don’t think that explains the confusion (especially as my main issue is that Matt Ridley claims a specific value rather than a range and Nic Lewis appears to be unwilling to acknowledge a range). Even acknowledging your numbers would be a start. A possibility of it being above 3 degrees, is quite different to “it will probably be 2 degrees”. I’ve also just managed to have a quick look at the figure caption which suggests that those are ERF (although, I’ll admit that I’d never seen that before. I’d always taken the RCPs to be forcings by 2100, but that’s not quite right). However, the point is still that even the EBM estimates suggest a possibility of more than 3 degrees by 2100.
troy,
Actually, maybe you can clarify something. That figure you show is relative to the mid-1800s. The previous figure in the document is relative to the mid-1700s. Is that part of the difference? So, of course, one issue is whether or not we’re referring to the temperature rise since the mid-1800s or relative to pre-industry (mid-1700s).
I think China will go green pretty quickly. The concern in the US is the next elections. Democrats are already faltering.
Republicans are not interested in Green and are expected to push for Keystone XL and further tar sands extraction. (Tar sands… we burn coal to melt rock hard tar, to make crude. It has a high carbon footprint.)
The interesting thing about the US-China announcement was in the justifications
2 C is a useful marker we don’t want to excede – Yep
Scientific consensus on the dangers of climate change – Yep
Technologies to reach these goals economically available- Yep
Reasonable economic pathways to mitigation – Yep
Different pathways for different countries – Yep
Ok, they bought into carbon capture, but politicians can dream can’t they
ATTP,
That may contribute to some of the difference, although it is not as if the forcing change from 1750 from 1850 was particularly large (I believe < 0.1 W/m^2 if I am remembering the IPCC forcing diagram correctly). Also, from what I recall from the projections chapter and SPM of AR5, the temperature projections tend to be made relative to "today", or relative to 1850-1900…I can't recall an instance of temperature projections relative to 1750, perhaps because none of the major temperature indices go back that far?
Eli… with Carbon Capture, Coal costs more than wind or solar.
Do I understand correctly that the median for the temperature estimates with RCP6.0, using Lewis’ TCR, works out to ~2.0 C?
For Lewis: I appreciate you chiming in (well, on the other thread), but if you’re going to say that Ander’s estimates for RCP6 using your numbers are wrong, it’s helpful if you tell us what you believe the correct range and median are. If there’s a fat tail of probabilities, we would want to know what the odds roughly are for unfavorable warming: how likely is >2.0 C, >3.0 C, etc.
Troy,
Thanks, I’m still a little confused about the figure you highlight but you have made me realise that I’ve been misreading the RCP figures I’ve been using anyway. The RCP6.0 scenario peaks after 2100 and – as you point out – slightly below 6.0W/m^2. So, my estimates are too high. I get something like 1.2 – 3.3K relative to mid-1800s, so a little different to yours, but I’m not that interested in arguing about a few tenths of a degree.
Windchasers,
Well, my numbers are wrong given that I was over-estimating the forcing in 2100. Don’t think that really changes the point, though. It could still be – according to Nic Lewis’s own numbers – about a degree or so higher than suggested by Matt Ridley (or, rather, we can’t rule that out with high confidence).
Surely you can just call Lewis an ‘independent researcher’, a title which signals to anyone that he isn’t necessarily a scientist or even an expert.
I’d hate to play darts with Matt Ridley: he’d always be adamant he’d hit the bullseye.
Windchaser,
I didn’t answer your first question. The number that Matt Ridley presents in his article is the median of Nic Lewis’s TCR estimate and produces about 1.2K of warming from today, so around 2K since the mid-1800s.
There was a rather large disparity between how positive Anders tends to describe Lewis and how he reacted on the previous comment thread. A scientifically minded person should be comfortable talking about the uncertainty monster.
“The concern in the US is the next elections. Democrats are already faltering.”
Prognostications two years out are always a risky business, but I’ll disagree. Dem loss of the Senate was predicted long in advance, noting that the losses were largely marginal seats picked up in the Dem landslide year of 2008. Reps are severe underdogs for the presidency in 2016, noting that Obama’s approach to undertaking action by executive order has the effect of appealing to the many 2016 presidential voters who care about the policies much more than they do the parties or the personalities. Dems very likely won’t get control of both houses, but look what happened when they did. In any case, I expect a Dem president with control of one house at best, the latter not making much of a difference.
Are we *still* taliking about EBM results as if they;’re credible?
(pauses for a moment to slam head against desk)
Time for close of discussion and new post on something completely unrelated to EBMs. (How about that Donohoe et al. paper e.g.?) Seven out of eight posts is truly enough, unless you want to change the blog name to “… and then there’s EBMs,” in which case go for it.
“We” aren’t, Steve. Others are though.
Steve,
Fair point 🙂 I’m rather tiring of it too.
Windchaser:
Since I had already digitized this figure – http://climateaudit.files.wordpress.com/2014/09/fig2_ecs_tcr-bcs3-vol1a.png, I could probably answer your question. By my count, using the simplified method discussed by ATTP, the LC14 median T above pre-industrial in 2080 to 2100 for RCP6.0 is 1.8K. The other probabilities implied by that figure & method shake out as:
P(T <= 2) = 68%
P(2 < T <= 2.5) = 19.5%
P(2.5 < T 3.0) = 5%
Though my digitization was probably not perfect.
Unless I have misunderstood this, mitigation sceptics who argue for policy paralysis *cannot* use any RCP except RCP8.5 as all the others incorporate built-in emissions-reduction assumptions. So it’s no good Lewis or Ridley waving airily at RCP6.0 ~2100 and saying *anything* because if we follow the do-nothing approach then by 2100 we won’t be tracking something like RCP6 or RCP4.5.
Well, obviously something got interpreted as an HTML in my above attempt at a comment. That probability table again is
P(T LTE 2) = 68%
P (2 LT T LTE 2.5) = 19.5%
P (2.5 LT T LTE 3.0) = 7.5%
P (T GT 3.0) = 5%
Oddly Canada will be likely switching to Liberal in the next election. Justin Trudeau has nice hair.
Troy,
Thanks. So, roughly a 20% chance of more than 2 degrees relative to the mid-1800s and averaged over the period 2080-2100.
Troy,
Missed your revision, so more like a 30% chance of more than 2 K.
ATTP –
Yup, unless I’ve made a mess of the digitization or method.
Troy,
Sounds reasonable. You’re certainly done it more accurately than I have 🙂
BBD,
You make a good point. I was trying to find a few days ago what the assumptions were with regards to the different energy sources for the different RCP scenarios, and I couldn’t really find it. If someone knows, maybe they could point it out.
ATTP
This is useful and fairly comprehensive.
I think there is quite a lot to be said for analyzing the meta game here. Specifically, if you want to argue for low sensitivity, certain aspects of global warming data and analysis must be questioned.
If you do like Curry’s paper then, logically you must dislike paleo data.
I hadn’t thought that RCP was such a no no to them. I couldn’t figure out why they were arguing so much about it. Now it makes sense.
Me wonders what other trends we can expect given the current desire to push for low sensitivity.
Some, not Eli to be sure, might think the world ends in 2100. That’s just the lukewarmer’s fantasy.
Indeed, and even though I’ve just realised that the RCP6.0 pathway doesn’t reach its maximum at 2100, it only takes a few decades more before it does.
ATTP
Yes, yes, but it’s vitally important to squeeze the lowest possible values for TCR out of the data.
Rachel … Are not the Chinese famous for playing a long game. If they want to usurp US global leadership why not show that they are taking the lead on AGW? If US fails to honour commitments that diminishes the U.S. just as it raises China’s credentials. I could imagine China, in some decades, applying carbon tax on imported goods and services. If Congress fails to tax it, China could, unilaterally (by then WTO would be no more or radically reengineered). It’s a thought.
If I am not mistaken, the original RCP6.0 data from Meinshausen et al 2011 reach 5.52 W/m2 in 2100 for the total anthropogenic and natural radiative forcing. This value for the year 1850 is 0.41 W/m2.
See: http://www.pik-potsdam.de/~mmalte/rcps/
That would bring your delta T calculation to a range of 1.3 – 3.7 °C relative to 1765. The best TCR estimate of Lewis and Curry (their table 5) is 1.33, which gives a temperature change of 2.0 °C relative to 1765.
China have been investing heavily in renewables and they also have reasons other than climate change – like pollution and energy security – to shift away from fossil fuels. They may have other reasons for wanting to take the lead on AGW but does it matter?
Personally I think it’s wonderful that the US and China have got into bed together because at the very least it sends the message to everyone else that this is a serious problem and we must do something about it. They’ve made a commitment and this is a big thing.
It would also be great if a carbon tax which could be added to goods from countries that don’t have one.
For the record, I have a longer climate publication record than Lewis, and I often make a point to state that I’m *not* a climate scientist. It takes a lot of hubris to publish a couple papers and then claim you’re a scientist in that field.
On the US-China agreement, it’s very good news. It pledges that the US will accelerate its emissions cuts, from the current ~1% per year up to 2020 to ~2% per year from 2020 to 2025. To stay within our carbon budget for 2°C, we need to accelerate emissions cuts, so that at least puts us on the right path. Same for China – they need to get off their accelerating emissions path, and they agreed to do that with an emissions peak in 2030.
It’s movement in the right direction, and that’s very important. There’s only so much we can do in the near future (especially with anti-science Republicans in charge of Congress for the remainder of Obama’s term), but it’s a good start, and also nips the irresponsible “nothing we do will matter unless China takes action” cop-out in the bud. A high-profile committment from the world’s two leading net carbon polluters to cut their pollution can only be a good thing.
RCP6 does reach a 6 W/m^2 forcing. The peak happens shortly after 2100.
It has CO2 emissions peaking in 2060 at 75 per cent above today’s levels then declining to 25 per cent above today
Both can be seen here.
“Figure 16: Extension of the RCPs (radiative forcing and associated CO2 emissions) from van Vuuren 2011. (ECP is Extended Concentration Pathway).”
According to the World Bank last year, see Which Coastal Cities Are at Highest Risk of Damaging Floods?
“In terms of the overall cost of damage, the cities at the greatest risk are: 1) Guangzhou, 2) Miami, 3) New York, 4) New Orleans, 5) Mumbai, 6) Nagoya, 7) Tampa, 8) Boston, 9) Shenzen, and 10) Osaka. The top four cities alone account for 43% of the forecast total global losses.”
So, that’s 5 US cities, 2 in China, 2 in Japan and 1 in India.
I’ll admit I’m surprised Shanghai isn’t in the top 10.
See iamges of population densities. The US and China are rare in having long coastlines with large fraction of populations there and huge infrastructure investments.
Of course, Vladimir Putin will stand with Jim Inhofe (R-OK), Mitch McConnell (R-KY) in hating this China-US deal. AGW is mostly good for Russia (except hit to St. Petersburg), bad for US and China. Putin should love the work of Ridley or Lewis, which might be ironic.
Anders –
==> “Consequently, it’s not surprising that some might think that what motivates Nic Lewis is his ideological objection to the policy implications associated with mainstream climate science, rather than an intrinsic interest in climate science itself. Now, this may be an entirely unfair interpretation of Nic Lewis’s motives but, if so, maybe he could put a bit of effort into ensuring that it isn’t the obvious one.”
None of us are really in a position to judge Nic’s “motivations” with certainty,
My own assumption is that he is “motivated” to do accurate science (out of intrinsic interest) and to evaluate the probabilities related to differing degrees of ACO2 caused climate change as carefully as he can. I don’t see any particular reason to think he has other motivations. I assume that pretty much everone engaged in these discussions has that same “motivation.” But it only an intuitive assumption. Maybe if I actually know someone personally, I could have some inside knowledge related to motivations – but just judging from scientific output or blog comments? I think you can’t judge “motivations” in such a manner, and anyone who does is making fallacious arguments. It’s a true wonder how so many smart and knowledgeable people can so readily, and apparently w/o much ability to evaluate the cogency of their own arguments, judge the motivations of others (by reverse engineering from scientific opinions expressed) when they lack evidence. It is such an obviously flawed reasoning mechanism.
Sure – it’s possible to speculate and express uncertainty about motivations. That’s better than the fallacious certainty I seen in judgement made about motivations that I usually see. But what’s the point, really? What is the benefit of speculating?
But then we’re left with questions such as what explains, for example, Nic’s lame-ass defense of Ridley’s rhetoric w/r/t uncertainties? How can it be understood?
I think that what might be of use here is to consider that if we talk about someone’s “motivations,” were are forming (basically) unsupported judgement about them personally but when we talk about someone’s “motivated reasoning,” we are talking about their reasoning. We can legitimately formulate judgements about someone’s reasoning.
So I think there’s a problem with your comment in that it offers, basically, a false choice by assuming that we can’t engage in “motivated reasoning (in other words, be influenced by our ideology – aren’t we all?) even as we are motivated by intrinsic interest in the science
One could reason fallaciously due to opposition to policy implications of mainstream climate science, and indeed – even the full range of implications of his own scientific output (as I think that Nic has just demonstrated in his comments about Ridley*) – and still be motivated by an intrinsic interest in climate science itself.
Richard Erskine: I had interesting discussion with an Asian business man. There’s often this notion in the west that China actually cares about us. I don’t think they really do. They won the Cold War, we certainly didn’t. The bulk the the Earth’s future weath is in Eurasia.
Anyways, markets over here are small, we don’t speak their language. Seriously, would you get out of bed for that?
If it’s posturing, it’s posturing for their own people, not us.
We’ll be seeing a lot more analyses like this one over the next few days, weeks, and months to come.
What You Need to Know About U.S.-China Climate Pact by Brian Kahn, Climate Central, Nov 12, 2014
“Joshua says:
November 13, 2014 at 12:00 am
My own assumption is that he is “motivated” to do accurate science (out of intrinsic interest) and to evaluate the probabilities related to differing degrees of ACO2 caused climate change as carefully as he can.”
Then why does he make judgements which influence his results towards lower TCR values (such as not including BEST and CW2014 during analysis). If you use their numbers his study would report TCR values which are ~10% higher… but he hides behind the “IPCC uses the other three so I will only use them” defense. If one were genuinely skeptical you would test the limitations of the various approaches and estimates and discuss the sensitivity of the estimates…
Lets review now though – compared to LC2014 the surface temperature changes have been greater, the forcing change estimate is actually lower (see recent volcanic paper at GRL in press) and OHC is underestimated compared to what is probable. Three biases all suggesting a higher (substantially) TCR value. So where is Nick Lewis saying the reasonable (truly skeptical) thing that the estimate is likely on the low side? Nowhere to be seen. No ‘true’ skeptic would ignore those points above…
The ironic thing is how often contrarians accuse scientists of being overly assertive about their results and yet they willingly accept results like LC2014 which clearly have issues but yet has been heavily promoted. Where is the outrage at a study picking and choosing which datasets to use…
Interesting that the Chinese live with their head in the future and extrapolate (without physical model) with confidence. Let’s see how stable the region and the countries are and whether they are able to make the transition to democracies.
> Then why does he make judgements which influence his results towards lower TCR values (such as not including BEST and CW2014 during analysis).
Some, but not Eli, would argue that it’s the lowest bound of justified disingenuousness.
Mike H.,
Yes, I’ve already updated the post to reflect that. I hadn’t realised (until Troy pointed it out above) that this was the case.
Joshua
Etc.
Sometimes, it’s more useful, more realistic to call a spade a spade. All these words just obscure the truth.
WIllard
Re: “justified disingenuousness”. I think this is one of those catch-phrases like “suboptimal”? But shorn of its original context it puzzles me whenever I see it. How can disingenuousness be justified? Is it not intellectual dishonesty? Can you gloss this for us?
BBD,
The problem I have with calling a spade a spade is that it essentially destroy any chance of dialogue. Of course, this post may essentially do that, but I would be genuinely impressed if someone like Nic Lewis came along and tried to have a serious scientific discussion. Maybe he just doesn’t know how to do that. Maybe he really thinks that science works by publishing a paper and then arguing that your work is better than everyone else’s while ignoring all the caveats with your own work. Given who he hangs around with, maybe noone’s ever told him that you gain credibility by acknowledging the issues with your own work and lose it by trying to sell it as if it’s a competitive market. I’m idealising slightly, as clearly people do try and sell their work (by talking at conferences, etc) but normally you don’t do it by highlighting the caveats with all the other work while ignoring your own.
ATTP
I am past the dialogue stage with libertarian activists. They themselves do not exhibit the intellectual honesty necessary for productive conversation, so it’s just throwing things at the wall. They need to be opposed, not excused or explained or accommodated. Having children strengthens the resolve in this respect no end.
BBD,
Well, to be honest, I’m rather running out of people with whom I think dialogue is possible or worthwhile. So, maybe I’m just clutching at final straws. I think I just don’t know how else to engage. If dialogue isn’t possible (and I kind of think it isn’t) what am I trying to do? I don’t know the answer.
ATTP
Dialogue with the fundamentalists was never on the cards. But debunking is vital. You have, for example, demonstrated the ways in which NL has fallen short of proper scientific objectivity and engaged in a kind of advocacy instead. This is the fuel on which opposition runs. There aren’t nearly enough public voices doing what you are doing and in that you can – I hope – see what you are doing and why it is essential. You could discount this as morale-building soap, but the number and calibre of the commenters here speaks for itself.
“Given who he hangs around with, maybe noone’s ever told him that you gain credibility by acknowledging the issues with your own work and lose it by trying to sell it as if it’s a competitive market.”
+1 🙂
Last weak I send out an email to the homogenization community, praising the work of a young colleague and requesting everyone (who can) to participate. When someone raised doubts, I upped my game by saying that the previous study had a big problem. That was my study.
At least that gave me some credibility. 🙂
BBD,
Got to be careful about that. If I wanted more readers and more comments I could just parrot what is said on WUWT 🙂
Victor,
Hope you manage to publish a new paper pointing out that your old paper was wrong 🙂
Here, BBD:
Matt & Nic have little choice. That’s a lukewarm price to pay to try to influence policy.
I’m not sure it implies any kind of bankruptcy, but I leave that to Matt & Nic, who are more authoritative on such matters.
Willard,
Well – assuming I understand you – that has essentially been my point (or, related to it). If those who promote low climate sensitivity were to acknowledge that there is a non-negligible (greater than 1%, say) chance that climate sensitivity may be higher than they suggest, their policy arguments largely fall flat. Hence, my desire to either get them to acknowledge this issue, and/or – maybe more interestingly – to stick with their policy preferences without ignoring all the evidence for higher climate sensitivity (which may be almost impossible to do).
Willard
Ah. I see now. Thank you.
ATTP
Nooooooooooooo!
🙂
Robert –
==> “Then why does he make judgements which influence his results towards lower TCR values (such as not including BEST and CW2014 during analysis).”
Has he addressed that question? I assume that he has a technical answer, and one that he believes to be accurate – perhaps something along the lines of…he doesn’t think BEST and CW2014 methodology were valid)?
What is your answer to your question? Do you think that Nic thinks that including those results in his own analysis would be the best thing to do from a scientific perspective, but because he is motivated to contradict mainstream science related to sensitivity ranges – he therefore excludes those analyses so as to produce results with a lower range?
Joshua,
The only answer I’ve seem him give is that Lewis & Curry was based on data accepted by the IPCC and hence BEST and CW2014 are not appropriate (or something along those lines). I don’t find it particularly convincing, given that the IPCC is simply a synthesis report and actually validate data.
Anders –
If that’s the reason, it would be interesting. On the one hand, it would make some sense to me to say “I think that the IPCC is wrong – therefore I will use the same data they use and perform my own analysis and see what happens.”
On the other hand, it would suggest that the “motivation” is to produce results in disagreement with the iPCC’s conclusions – as opposed to pursuing in intrinsic interest in the science.
A problem for me – as someone who can’t evaluate the science at a technical level – is that I see certain claims made about “motivations” on both sides, e.g., that CW2014 can be dismissed because clearly the authors (by virtue of being associated with the
GWPFSkeptical Science are clearly activists, and thus “motivated” to produce a certain kind of result. I don’t dismiss the possibility that people are “motivated” to skew the science to support ideology, but: (1) I don’t think certain claims about “motivation” can be validated (and thus raise questions for me about the reasoning of the person that’s making those certain claims) and, (2) such logic implies that the person producing the science is, essentially, sociopathic – willing to knowingly risk “millions of poor children starving” merely to advance a partisan agenda.Getting back to the US-China climate agreement, the following observation about the current state of politics in the US struck a chord with me.
We’ll wait to see the details—including how an American president can make good on commitments for 2025, when that is two and possibly three presidencies into the future, and when in the here-and-now he faces congressional majorities that seem dead-set against recognizing this issue. It’s quaint to think back on an America that could set ambitious long-term goals—creating Land-Grant universities, developing the Interstate Highway System, going to the moon—even though the president who proposed them realized that they could not be completed on his watch. But let’s not waste time on nostalgia.
Is the US-China Climate Pact as Big a Deal as It Seems?by James Fallows, The Atlantic/Mother Jones, Nov 12, 2014
Joshua,
I certainly don’t think that one should dismiss something because of a possible author’s motivation. So, I have no issue with Nic Lewis’s papers as they’re perfectly understandable and all the assumptions are present. They can be reproduced. If I have an issue, it’s with how they’re used publicly.
What I find interesting/confusing is that if this was any other field, something like an energy balance calculation would probably be seen as a sanity check. You have results from complex models (GCMs). You have results from others observations (paleo). Then you do a basic calculation (EBM) and you get something slightly different, but with a large overlap. Normally you’d expect people to conclude that the range you have is probably okay. Instead, these EBM results get used to argue against other results simply because they tend to skew the distribution to lower values. This is especially annoying given that what’s not included and what is ignored would mostly increase the estimates somewhat.
> Hence, my desire to either get them to acknowledge this issue, and/or – maybe more interestingly – to stick with their policy preferences without ignoring all the evidence for higher climate sensitivity (which may be almost impossible to do).
Reminding this matters more than pretending we’re having a conversation.
Bankrupt conversations should be left to those who are authorities on bankruptcy, like Matt & Nic.
Joshua
The GWPF is a political lobby group. It is partisan. It is *not* driven by scientific objectivity. It speaks contrary to the scientific consensus. This is the context within which NL operates. As ATTP says, what he publishes is internally coherent but it is also tactical in the methodology employed and the data choices made.
There *is* a world of difference between what the GWPF is doing and what SkS is doing – which is to inform about the state of scientific knowledge to combat political lobbying. You seem to apply a kind of false equivalence to all this which leads to incorrect conclusions as above.
Anders –
==> ” Instead, these EBM results get used to argue against other results simply because they tend to skew the distribution to lower values.”
Except (as I understand it) the argument made is that those results are based on a distinct, and superior, methodology. That seems to me to be, potentially, a coherent argument.
==> “This is especially annoying given that what’s not included and what is ignored would mostly increase the estimates somewhat.”
At some point, it makes sense to question whether that is purely a coincidental outcome of scientific decisions made about methodology – and the way to evaluate that is to examine the scientific basis for the methodological choices. If there is no such argument made about the merits of the respective methodology, then there is a bit of a dilemma.
But I can’t evaluate the arguments about methodology anyway. What I can see, however, is the glaring inconsistency in Ridley’s approach to uncertainty, and Nic’s unfortunate, lame-ass defense of Ridley’s inconsistency. Your point about Ridley’s treatment of the range of probabilities stands, IMO – as do your points about the GWPF’s treatment of uncertainties more generally. Given that Nic is affiliated with the GWPF, and (ostensibly at least) is concerned with appropriately quantifying how uncertainties related to decision-making about energy policy, then it is certainly valid to wonder why he doesn’t confront Ridley’s, or the GWPF’s, inconsistency in treating uncertainty. But we’ll never have that answer about his “motivation,” and focusing on the question of his motivations and even more, concluding answers, seems to me to fit into the category of identity politics.
What’s relevant w/r/t your discussion of Ridley’s arguments and Nic’s failure to address your points, IMO, goes back to a more fundamental issue: how to approach decision-making in the face of uncertainty. There are uncertainties -w/r/t probabilities related to sensitivity and w/r/t the economic impact of different magnitudes of warming. In a sense, IMO, arguing about a constrained and putatively “best” quantification of those uncertainties is a valid scientific topic, but when we transition into the policy discussion it becomes a distraction because we know potential of low probability/high impact events needs to be included in policy discussions. Determining a “best” range does not eliminate the uncertainties about less probable events. It seems to me that to help us along in the discussion of decision-making in the face of uncertainty, we need to include what we know about how “cultural cognition” biases how people reason in politicized arenas that stimulate identity-aggression and identity-defense – and I think that arguing about motivations does not net positive results in that regard.
Not sure what does net positive results, however. 🙂
Not at all. The Lawsons and Ridleys and Lewises and Montfords of the world are absolutely certain that they are right. Therefore as far as they are concerned, no matter what corners they cut, tactical views of the data they take or truths they bend, they are emphatically *not* risking future generations etc. Everybody who disagrees with them is guilty of that.
Why not listen to the scientists who en masse disagree instead of talking all the time?
See above.
Of course it bloody isn’t.
As you might say, Jeebuz.
> Why not listen to the scientists who en masse disagree instead of talking all the time?
Talking heads that stop to talk may have to declare bankruptcy. Matt may not be able to afford another one.
BBD –
==> “Why not listen to the scientists who en masse disagree”
I do listen, and what they say helps me to estimate probabilities. Since I can’t understand the technical arguments, that’s the best I can do.
==> “instead of talking all the time?”
Good point. There’s a lot I need to do. Catch you later.
BBD raises an interesting point. There is a sense that some see the GWPF on one side and SkS on the other, and I really don’t see how this is reasonable unless you believe that the middle ground is partially mis-informed. What are SkS really advocating for? Don’t increase our emissions to the point at which we risk climate disruption? Hard to see how there’s anything wrong with that. I know you can find articles on their site that discuss alternative energy, but most of it is science and I’ve yet to find anything that is not broadly correct. It is arguably one of the best scientific resources about climate science on the web. Also, from what I’ve seen, if anyone were to politely ask John Cook or Dana Nuccitelli to clarify something, I think they would. I don’t think they’d resort to nitpicking at what you’ve presented when asking the question. There are some who think that SkS can’t be trusted, but those also seem to be the same people who think that the public shouldn’t be presented with a fair representation of the evidence, so I don’t really care what they think.
ATTP: Although John Cook and Dana Nuccitelli are the public faces of SkS, there are a number of other very knowledgable members of the SkS author team. For example, Rob Painting is an expert on what’s going on in the world’s ocean systems. By and large, all members of the SkS author team are very polite in responding to questions.
For the sake of journalist integrity, I am a member of the all-volunteer SkS author team.
JH,
Indeed, I was just throwing out two names of people who are associated with SkS. I agree, all who I know I would regard as people who would respond constructively to polite criticism or questions. They even respond well to those that aren’t polite, TBH 🙂
BBD,
There are differences between different lobbying activities, but the goals of SkS are very clearly political. It’s not there to inform about the science just because correct scientific knowledge has high inherent value. The differences between SkS and GWPF are not that fundamental.
Of course, there are also differences, but lobbying activities are basically legitimate. When GWPF presents erroneous or seriously misleading information, that should be pointed out, it’s also right to argue against views that are questionable in other ways.
Joshua: As an engineer who faces uncertainty all the time, I (we) take an extraordinarily conservative approach to dealing with it. You can’t sell a product that might, mostly, kinda, sorta work. Where possible products are over engineered. Under engineered products are always inferior. (I used to have a Hyundai Pony, it was a great car until it caught fire. It was cheap though.)
Turning this discussing back on itself, we are terraforming the planet to a new state. We have no plan, no idea where we’ll stop, and no clue as to the negative uncertainties, and no idea whether it can be fixed. Yet at this time what we do know is that what we are doing will be very bad, very expensive, and likely much of it irreversible.
Would you buy a car built to those exacting specifications? No.
Would you get a treatment from a doctor with those potential results? No.
If this was an engineering project it would end with a lawsuit. (Been there, done that. Used the experience to prevent another company from doing the same.)
SkS is only political in the sense that it represents digestible peer-reviewed science to the public.
It is an odd world where that is seen as a political act. Very odd.
Pekka,
In what sense is it political? In the sense that you think it is, or in the sense that they explicitly say so?
This is from their about page
So, it seems that you’re assuming that they’re political because that’s how you think they are, even though they don’t explicitly say so, or because it’s a political topic, in which case they are by default.
To be fair, I’m not disputing that they clearly are playing a role that could be regarded as political, because it’s hard not to when you engage in this topic. However, the site is predominantly about climate science and reporting on climate science (with some exceptions).
The problem I have with the whole GWPF balance SkS type of framing is that it doesn’t make logical sense. There can always be opposing side to an issue, but that doesn’t mean that the two sides are somehow equivalent. If it was simply something about which we could all have an opinion, it might be the case, but when it’s predominantly a science issue, it doesn’t appear reasonable. When the GWPF talk about science they present a very narrow and cherry-picked scientific view and often promote things that are easily shown to be wrong. From what I’ve seen, when SkS presents information about science it is generally a fair representation of our understanding. I fail to see, therefore, how one can really see the GWPF and SkS as somehow equivalent but on opposing sides.
Anders, Pekka, the answer to those who don’t want partisan information is to go read the science. i.e. the IPCC summaries.
The issue here is that most people don’t know what science is, let alone can understand how to read it. Heck, I didn’t even use measurement/calculation uncertainties until first year university.
I think the GWPF is capitalizing on Joe public’s inability to understand those things that are technical.
AoM,
I agree and that is what often confuses me. This is primarily a risk assessment issue and we would never be comfortable with the level of risk we face wrt climate change if it was the same for driving or flying, for example. Our day-to-day risk aversion is remarkable (in the developed world at least) and yet we seem comfortable with a greater than 1% chance of more than 4oC by 2100.
jsam/Anders, I really do see SKS as political. Its not like its actually doing the science.
Make no mistake… I like Skeptical Science, and I use it as a crutch after I’d reviewed half a dozen numpty claims from deniers, and realized Skeptical Science came to the same technical conclusions. Ergo, I trust them on a technical level.
But to someone coming from a non-technical point a view there is no way to distinguish. So.. send people to the experts, go read the IPCC summaries.
Agreeing with me confuses you? 🙂
jsam and ATTP,
Do you think that only those are political, who promote views that are different from yours?
Do you think that SkS would exist in its present form with the motivation of affecting policy decisions in some way?
That their approach is to argue against claims about science that they consider wrong, does not change the basic motivation for the site.
The issue is not the pure scientific knowledge, it’s how science is used in influencing policies. That’s political, even it it’s not party politics.
Hmm. I detect a word dance.
If representing peer-reviewed science to influence policy is political then what word best describes representing falsehoods to influence policy?
Pekka
While I understand what you are saying, I don’t agree that SkS is at all comparable to eg. GWPF.
SkS seeks to clarify and explain the science so that it will not misinform the policy making process. GWPF misrepresents science in order to misinform the policy making process.
Therefore, I must disagree strongly with your statement:
BBD,
People with different views of climate policy might say that GWPF seeks to clarify points that have been mispresented or not given enough weight elsewhere.
You may believe firmly that SkS moves the balance of understanding to the right direction while GWPF does the opposite, but that’s your personal judgment.
Hmm. No, Pekka, it is more than a personal judgement. Maintaining the earth is round versus maintaining the earth is flat is more than a personal judgement.
I don’t view SKS as a political organisation. It must be possible to have an organisation whose goal is to communicate science to the public without it being political. Whether SKS achieve this goal 100% of the time I can’t say for sure but from what I’ve seen, they do pretty well. It’s fine to tell people to go to the IPCC reports but these are boring and long and not great as educational material for the general public. That’s not their purpose anyway. SKS take this science mumbo jumbo and turn it into something more easily understood by a general audience. It’s not political to do this. The science is still the same, it’s just in a more readily digestible format.
There are a few climate science blogs that I would classify as totally apolitical. As a very clean example I would pick Isaac Held’s blog. It’s not the only one, but most of the sites have some political coloring.
Several of the sites of other climate scientists may be close to that of Held’s. SoD has also been pretty good in avoiding politicization.
Pekka,
I think you’ve left some questions on the table.
If representing peer-reviewed science to influence policy is political then what word best describes representing falsehoods to influence policy?
In what way is stating the earth is round political – other than to counter the earth is flat PR?
Yes, Pekka, I don’t understand either what’s political about presenting the science in a manner that a more general audience can understand provided it is true to the science? What’s political about this?
> The differences between SkS and GWPF are not that fundamental.
There are budgetary differences, which I would characterize as fundamental.
Symmetries break down quite fast.
Rachel, I see Skeptical Science as picking and choosing what they talk about and why. That’s why I see them as partisan. In many cases I see them as choosing to directly fight BS from denial.
I consider IPCC as non-partisan since its just summing up the science. Its not picking and choosing.
I consider Skeptical Science credible as I can understand their motivations, and I can understand their technical content.
GWPF has done much to obfuscate its motivations, and actively cherry picks what its talks about and why. Its pretty obviously a member of the denial machine. About them I am incredulous.
To Joe public Skeptical Science isn’t much different than Green Peace or a bunch of hippies. That is certainly how the denial machine paints them.
jsam,
Peer reviewed science can be presented in many different ways. There’s also a lot of freedom of choice in selecting, what to present. The choices of SkS have a strong connection to influencing policies.
There’s nothing wrong in being political. It’s important that valid arguments are brought to policy related discussion. When that’s done in support of of certain views and in purpose of weakening arguments presented by a political group that’s political activity. A site that would search actively weak points from the arguments of all sides might be non-political, but that’s not the idea of SkS.
There’s no fundamental difference between Pekka’s contributions and the GPWF’s.
They both have fundamental political components.
Cf. Aristotle.
Pekka – thank you for your response. But I still consider that it has not directly addressed the two, overlapping, questions.
If representing peer-reviewed science to influence policy is political then what word best describes representing falsehoods to influence policy?
In what way is stating the earth is round political – other than to counter the earth is flat PR?
Pekka
I’ve missed fast moving exchange here, but I reject this too. It is not a matter of subjective judgement. You astonish me.
Since you essentially ignored what I said, I feel obliged to repeat it:
SkS seeks to clarify and explain the science so that it will not misinform the policy making process. GWPF misrepresents science in order to misinform the policy making process.
There is a world (see jsam) of difference.
Joshua says:
“A problem for me – as someone who can’t evaluate the science at a technical level – is that I see certain claims made about “motivations” on both sides, e.g., that CW2014 can be dismissed because clearly the authors (by virtue of being associated with the GWPF Skeptical Science are clearly activists, and thus “motivated” to produce a certain kind of result. I don’t dismiss the possibility that people are “motivated” to skew the science to support ideology, but: (1) I don’t think certain claims about “motivation” can be validated (and thus raise questions for me about the reasoning of the person that’s making those certain claims) and, (2) such logic implies that the person producing the science is, essentially, sociopathic – willing to knowingly risk “millions of poor children starving” merely to advance a partisan agenda.”
Well one of the challenges when it comes to perceptions is that public faces are often the focal point and all the same qualities are applied to everyone involved in the organization. Do I think that everyone in the GWPF has the same set of views? No – that’s why I base it on the individual and their individual perspectives. The problem is that writers for SKS are not given the same respect. Do I hold the same views as everyone who writes for SKS – clearly not. I disagree with John and Dana sometimes and sometimes they disagree with me. It’s like any group of people – everyone has differences of opinion and that’s fine. We also have different specialities and I tend to do more cryospheric related things. The ironic thing is that I’ve been attacked for contributing to SKS but yet not about the individual articles I have written but rather just for the act of contributing itself. Somehow writing about science for a website that does climate change communication is considered activist – as if informing people on what’s going on in the cryosphere is a purposeful decision to be an activist.
That’s me, on the right, btw.
Joshua says:
“A problem for me – as someone who can’t evaluate the science at a technical level – is that I see certain claims made about “motivations” on both sides, e.g., that CW2014 can be dismissed because clearly the authors (by virtue of being associated with the GWPF Skeptical Science are clearly activists, and thus “motivated” to produce a certain kind of result…”
The second issue is that if you read CW2014 and a couple of other recent papers on the topic you have to accept that there is in fact a low bias in CRU and NOAA. This is fact. It is proven that infilling the global average will diminish high latitude changes. So either it is to be accounted for (and at least mentioned as a caveat) when doing a study or it isn’t. But pretending it didn’t happen and hiding behind the IPCC is purposefully putting forth a result that you know will be lower than in other datasets. Nick Lewis has been challenged multiple times to provide the reasoning and the results and has avoided doing so because he knows this simple change will raise the media TCR by ~10%. It was even brought up to him before submitting that he should include CW2014 but their decision was to only do that if the reviewers asked. Personally I would never go around arguing how robust my result is if I know that there are such clear examples of it being biased low but at the end of the day I only really care about the science.
That’s why the whole activist thing is somewhat funny to me. I’m not advocating for political movement towards a predefined carbon solution. I only advocate political movement towards acceptance of science and preparations for impacts (particularly in the north). I’m pro-science and anti-misinformation – I guess that makes me an activist.
It makes you honest.
It seems that maybe some discussion has been related to a comment I made, and it appears my point might not have been understood:
I was presenting a theoretical argument – not my opinion.
My point was not to argue that GWPF and Skeptical Science are equivalent – but to say that we’ll see reverse engineering about “motivation” based on “positions” about the science on both sides: and that I think that such reasoning (without passing a high bar of evidence) is inherently fallacious, and that if you ascribe to such reasoning on one side, then you are saying that the mechanism of reasoning is valid and thus, you have no objective way (at least that I can see) to defend your “side” against such reasoning. My point is that the method of reasoning is fallacious, and should be regarded as such. Personally, my impression is that arguing about the distinctions or lack thereof between Skeptical Science and GWPF amount to same ol’ same ol’ – identity politics, territorial battle between Otters. The focus should be on the arguments presented, not who presented them, and certainly not which label can be applied to the group that individual identifies with.
However, that doesn’t mean that you can’t identify “motivated reasoning,” in other words – reasoning that isn’t logically coherent and that can be explained only as a random outcome, or the outcome of a priori biases, subjective presumptions, etc. And you can also, certainly, point out the patterns in the reasoning (including fallacies) in the arguments that are typically presented by people of different group identification.
I hope not, BBD:
http://knowyourmeme.com/memes/am-i-the-only-one-around-here
Not that it really makes my word salad less confusing – but I think I meant “subscribe” in place of “ascribe.”
Jos Hagelaars,
Rachel just found your comment in spam. Thanks. That probably somewhat explains the Figure that Troy highlights (which is relative to 1850). It does mean that my original calc was too high, but it does still suggest that more than 3 degrees relative to the mid-1800s is not ruled out by Nic Lewis’s work.
Willard
No, no, not to that extent. I really need to watch TBL again – it’s been, like decades, man.
And it is. I had hoped to have made that clear above.
BBD: Calm down and remember, The Dude Abides.
Okay, let me go back a few steps. If people are arguing that this is a fundamentally political topic and those involved are doing so because of the political implications, then I agree. Neither SkS not the GWPF would exist if that were not the case. My point was about there being some kind of equivalence or symmetry. There’s a big difference – IMO – between and organisation trying to inform and one trying to directly influence. Also, where is the middle. It’s certainly not somewhere between SkS and the GWPF (or WUWT or Bishop-Hill). It’s pretty much where SkS is. Ask yourself this. If someone who was unaware of the background or the characters involved, and simply searched for information on ocean heat content. Would they be more informed if they read something on SkS or read one of Bob Tisdale’s post on WUWT? I hope the answer is obvious (in case it isn’t, the answer isn’t Bob Tisdale on WUWT).
Anders… I agree.
Pekka – Reality is just _not_ a matter of “…your personal judgment…”. In fact, reality cares not one whit about anyones judgement.
Whatever your views on their political content, there is a fundamental difference between SkS, RealClimate, etc. on one hand and the GWPF, WUWT, and others on the other. One group presents demonstrable reality, the other denies it. One group seeks to inform, the other to misinform.
I’m more than a bit stunned that you could consider them equivalent; relativistic judgements are _not_ equivalent to verifiable correspondence with reality.
I agree as well. Technically the SkS posts are good and fairly present the scientific understanding on the topic as far as I can judge.
Back to the theme of the simple models of Nic Lewis and complex global climate models. I see not fundamental difference between the two, both use models, both fit to the data. A differences is the complexity of the models, which is a pure matter of taste, or better, using a range of complexities is more valuable than having studies with just one degree of complexity. Another difference is the degree of tuning. NL method is fully tuned, global climate models are not explicitly tuned, but likely implicitly they are tuned somewhat (if a change makes the fit to the historical data worse, it may not be implemented even if theoretically better than the old version). In meteorology tuning is looked down upon, but in hydrology it is completely normal. Thus I would say this should not be seen as a disadvantage of the simple models, just as a matter of taste.
That these methods produce different values for the climate sensitivity is thus surprising and something that should be studied. Anders already presented some ideas why the method and the data used by NL is biased to producing too small climate sensitivities. In this way NL studies help in understanding the limitations of these simple models and especially their large structural uncertainty, which may be larger than the statistical uncertainty produced by one method alone.
This is not my field, thus especially in this case I would be curious what the others think of the above argument. (To end my comment, like Anders would. 🙂 )
Victor,
To me there are two ways to look at this. Scientifically, one might look at the different methods, consider why they might be different, and maybe design something that could help to improve our understanding. Maybe improvements to climate models. More Argo floats. Better estimates of aerosols (another satellite, maybe). Try to determine if there really are inhomogeneities in the forcings. etc. Maybe in 10 or so years time we’ll understand why they produce different results.
However, from a policy perspective, what do you do? Do you go “thank goodness, we now have an estimate that suggests climate sensitivity might be low, we can relax for a while”. I would say you can’t do this. Maybe these new estimates change the balance of risk, but they don’t really reduce the possibility of a high climate sensitivity substantially. Sure, if we were already making drastic changes to our economies we might go “okay slow down a little”, but given what we’re currently doing, slowing down would almost imply going in reverse.
I am not sure whether more data would help so resolve the differences. Both fit to the same climate data, right? Or are there differences in the forcing data. The simple model of NL probably cannot even use more detailed measurements, because it does not resolve such details.
If you have one new method that produces a very different results than a number of other older methods, the reason for the difference is most likely the new method. Only if the new method shows that an older one is wrong, which is not the case here, I would prefer a new method. Otherwise, I would prefer older methods whose strengths and limitations are much better understood. Consequently, I see personally no real policy relevance to these studies using simple models until we understand where the differences come from.
Victor,
Two things that would help would be better OHC data and a resolution of the polar amplification issue. I also think understanding the inhomogeneities could also help (Shindell for example). The latter part of my previous comment was consistent with your second paragraph above. Unless the new method is demonstrably an improvement over the older methods, then I would also stick with the older ones until the discrepancy was resolved.
Also my view.
Perhaps one of the SkS regulars commenting here could say where the following came from, what exactly it was supposed to mean, whether it represented the consensus position on climate change impacts when it was written (2010?) and whether it represents the current* consensus. Under the heading ‘Health’:
http://www.skepticalscience.com/global-warming-positives-negatives-basic.htm
Expected to be five times greater by whom, where, when, under what level of warming and with or without adaptation? Regional, global, 2100, next week? Single study? Review? IPCC grand review? Some bloke down the pub?
It’s plausible that extra heat deaths could outweigh avoided cold deaths by five to one in some circumstances but you’ve got to say what those circumstances are. Otherwise you’re just brandishing scary slogans. Activism, not science.
(The Intermediate version of that pluses and minuses section is what first turned me against SkS. You can’t present a fair picture of ‘What the science says’ with a few brief summaries of single studies. Worse, the single studies on the minuses side seemed to have been picked solely for their doomtasticness and those on the pluses side solely for their triviality: ‘millions will certainly die’ versus ‘the lesser spotted piffle ant will probably have slightly greater foraging opportunities’, or thereabouts. Ill-conceived science education or well-conceived tribal mischief? IMO it was the latter. And IMO the essential SkS hasn’t changed since then. It just disguises what it’s all about a little better.)
===
*The AR5 chapter on health doesn’t attempt such a ratio, saying only that the increase in heat-related deaths is [some probabilistic tag; can’t remember which] to outweigh the decrease in cold-related deaths in various locations and circumstances.
You mentioned once that NL assumes that the Earth is not in equilibrium at the beginning. It should be possible to estimate how much disequilibrium is reasonable and its confidence interval. The nice thing of such a simple model is that you could apply it to a multiple values of this confidence interval (Monte Carlo sampling) and estimate the uncertainty in the climate sensitivity from the uncertainty in this assumption.
Then I think you once mentioned that the NL is biased to low because it cannot take variability (or non-linearity?) into account. It should be possible to quantify this bias and remove this bias from the estimates of the climate sensitivity.
Not using the best estimate for the temperature trend is simply a mistake. If you have evidence against the Cowtan and Way estimates, you should at least use all common/reliable estimates. Not just pick one.
If these three things are corrected, would you expect that the climate sensitivity of Lewis would fit again to the estimates from global climate models? Or do we need to search for further reasons for the differences? I understand that you cannot give numbers at this early stage, but what would you guess?
Victor,
Troy mentioned something about this and I think it is partly to do with regional variability which GCMs can include but EBMs cannot. An issue is whether or not GCMs can do this robustly. There is, however, also the issue of slow feedbacks (which, technically, are not included formally in the ECS, but will have an impact in reality).
If you reduce the initial system heat uptake rate to that used by Otto et al., use Cowtan & Way for the temperature, use the more recent OHC estimates, and there is a new paper suggesting aerosols may have been underestimated, then the climate sensitivity goes up. So, for example, you would then get a TCR around 1.5 (with a range from about 1 to just over 2) and an ECS just above 2, (with a range from 1 to 4.5 or something).
So, I don’t think these adjustments can get TCR best estimates of 1.8 and ECS best estimates of around 3. However, there is still the inhomogeneity issue that Shindell et al. suggested could be quite sustantial. Troy, again, however, did an analysis that I’ve yet to fully understand but that suggested that it wasn’t as substantial as Shindell suggested.
So, that’s not a great answer, but I think you make plausible adjustments that would bring the EBM estimates more in line with other estimates, but not completely. And it’s getting late, so that may not be quite as coherent as it should have been 🙂
Vinny
BBD, I had a look at the top two of those (one minus, one plus), before posting the comment. Neither said anything like five to one extra heat deaths versus avoided cold deaths. The other studies looked (still look) irrelevant, so I didn’t bother.
(Clicking on the plus link eventually takes you to what is essentially a UK government newsletter. Dunno if that’s SkS’s fault or an artefact of government website changes.)
AR4 WGII Section 8.5
Sorry, meant to say – not sure if this is connected but I wonder if it was where the 5 times came from.
Vinny, Instead of whining to us to because an old web page has link rot, why don’t you look up some useful information and inform yourself. Newer information is probably available and more definitive.
You clearly hadn’t read the last paper you presented to me to read. You didn’t know what its about, what it said, or what it meant. But that didn’t slow you up from casting useless aspersions.
It seems a waste of my time to attempt to inform you when you fail to even attempt to do that for yourself.
anoilman, what are you on about now? What last paper?
And it’s not an old web page. It’s the current web page you reach by clicking on the 3rd item from the top in SkS’s ‘MOST USED Climate Myths’ thermometer. (‘It’s not bad’.)
> reality cares not one whit about anyones judgement.
Vinny – looking at that SkS intermediate page, under Health, the first negative link is described as “Increased deaths to heatwaves – 5.74% increase to heatwaves compared to 1.59% to cold snaps (Medina-Ramon 2007)”, the link is live, and I believe it’s relevant to your question. Did you not see that?
Many SkS Myth Rebuttal articles were inittially posted as SkS Blog Post articles. Such was the case for the Intermmediate version of the rebuttal article that Vinny Burgoo finds fault with. The original blog post article, Peer reviewed impacts of glogal warming was written by John Cook and was posted on Jan 24, 2010. The introductory paragraph of that article reads as follows:
“If the IPCC’s mistaken prediction that the Himalayan glaciers would be gone by 2035 taught us anything, it’s that we should always source our information from peer reviewed scientific literature rather than media articles. Consequently, I’ve spent the weekend overhauling the list of positives and negatives of global warming so that all sources were peer reviewed. The list is by no means comprehensive and I welcome any comments mentioning other impacts of global warming found in peer reviewed papers (good or bad). Please include a link to either the abstract or if possible, the full paper. Note to skeptics – here is an opportunity to pad out the positive column if you can find peer reviewed papers outlining any benefits of global warming.”
Vinny Burgoo posted a lengthy critique of the article on Jan 25, 2010. Subsequently he and John Cook engaged in a brief exchange. It’s all documented in the comment thread.
Vinny Burgoo: Just because you can click on a link doesn’t mean its maintained. (Or that its science, or that it is reviewed.) Thank you for telling us that you think it is. However there are no internet fairies running around making sure every thing is right on an old web page or sciencing them up either.
That page is a healthy 7 years old, 2007. You first posted in the comments, in February 2010 right? Did you think it was new then? Do you think it got younger in the last 4 years?
Have you considered asking Skeptical Science? Maybe you could do that before coming over here? Wouldn’t that make sense? You already know that they listened to you and updated the site based on what you said, right? Why wouldn’t you ask them about this?
To me that means you (Vinny Burgoo) need to do more work before you start slagging SKS over here for brandishing scary slogans. I say this because you are the person with the quandary making accusations. I suppose you could keep on make blind accusations if you never ask them and they never fix it.
“It’s plausible that extra heat deaths could outweigh avoided cold deaths by five to one in some circumstances but you’ve got to say what those circumstances are. Otherwise you’re just brandishing scary slogans. Activism, not science.”
I loved this picture by the way…
KR: I don’t think that’s right. That works out to 3.6… not 5… and you could never derive that ratio as that paper was a past tense analysis of Americans in hot spells and cold spells.. You’d need a paper that took those rates by temperature, and combined them with future projections something like Hansen 2011.
http://www.giss.nasa.gov/research/briefs/hansen_17/
Its entirely possible John Cook had a brain fart.
anoilman:
No, John Cook did not have a “brain fart”. The Basic version of the Rebuttal article in which the sentence appears was written by GPWayne and was posted in Aug 2013.
Here’s the operative paragraph under the section header, Health.
“Warmer winters would mean fewer deaths, particularly among vulnerable groups like the aged. However, the same groups are also vulnerable to additional heat, and deaths attributable to heatwaves are expected to be approximately five times as great as winter deaths prevented. It is widely believed that warmer climes will encourage migration of disease-bearing insects like mosquitoes and malaria is already appearing in places it hasn’t been seen before.”
http://www.skepticalscience.com/global-warming-positives-negatives.htm
John.. Vinny wants a reference to the science behind that statement.
Vinny – you missed the challenge posed to you at http://www.skepticalscience.com/Peer-reviewed-impacts-of-global-warming.html#7610
“I would be quite happy if you were to take the time to find more papers showing contrary results to papers currently listed…It’s not a competition to see who gets the biggest list but an effort to portray the state of the science.”
Just do better science, Vinny. Just do better science.
(I note you don’t seem to be nearly as assiduous on WhatWentWrongWithThat. I wonder why. 🙂
jsam,
That link appears to support my earlier assertion. Vinny made some comments and criticisms. The author changed the post and removed references that weren’t relevant. Surely that’s a good thing? You can’t expect the author of something to change it completely, but acknowledging some issues and making some suitable changes is what one would hope for. Not sure I’ve seen that very often on WUWT, for example.
Vinny
Deep breath.
Look. The issue is not nit-picking about heat wave mortality projections. All I have to say about that is that heat waves kill people and there will be more heat waves in the future because physics. Any inaccuracy in the statement is rendered irrelevant by the *fact* of increasing mortality unless you think bickering is more important than people dying which frankly is the impression I am getting these days.
Now speaking of future mass mortality – but this time on a vast scale – how about pondering global food security in the latter half of this century instead? Which ties into water availability and also population growth. All this infuriating tr0llish diversionary crap you inject into comments here cannot begin to obscure the big picture so it would be nice if you stopped trying.
BBD says:
November 14, 2014 at 10:56 am
“…heat waves kill people and there will be more heat waves in the future because physics. Any inaccuracy in the statement is rendered irrelevant by the *fact* of increasing mortality unless you think bickering is more important than people dying which frankly is the impression I am getting these days.
Now speaking of future mass mortality – but this time on a vast scale – how about pondering global food security in the latter half of this century instead? Which ties into water availability and also population growth.”
Let’s also recall that paper published by the National Academy of Sciences (US) in 2010:
“An adaptability limit to climate change
due to heat stress”
http://www.pnas.org/content/107/21/9552.full.pdf+html
This is what the authors said in interviews:
“The Health Effects of Hotter Days and Nights”
http://www.gaia-movement-usa.org/?q=node/46
Quote: “”Most people are more familiar with the heat index, or the feels-like temperature they see on the weather report. The wet-bulb temperatures we are talking about would have a feels-like, or heat-index, temperature of between 170 to 196 degrees Fahrenheit,” Huber said.
“Researchers find future temperatures could exceed livable limits”
http://www.purdue.edu/newsroom/research/2010/100504HuberLimits.html
Quote: “”The wet-bulb limit is basically the point at which one would overheat even if they were naked in the shade, soaking wet and standing in front of a large fan,” Sherwood said. “Although we are very unlikely to reach such temperatures this century, they could happen in the next.””
This is about the physics of evaporation, where they’re talking about combinations of heat and humidity such that it slows down the rate of heat loss via evaporation such that it becomes not physically possible for evaporation to bleed off heat fast enough to avoid overheating. That is, they are talking about *wet bulb* temperatures high enough such that evaporative cooling becomes physically impossible. The *wet-bulb* temperature talked about above, where death for a human is essentially certain within several hours, is at least 35 degrees C or 95 degrees F, which according to the above is at least a 170-196 degree F *heat index*. They said that wet-bulb temperatures this high have not been seen on Earth for 50 million years. (Note that the mammalian kingdom we see today evolved after this on a cooler Earth.) This limit would within hours kill essentially any warm-blooded land animal (mammals and birds) that needs to perspire to avoid dying from overheating. This limit, according to the online heat index calculator below, can be achieved many ways. One way would be a dry bulb thermometer temperature of 105 degrees F with 75% relative humidity, or a dry bulb thermometer temperature of 100 degrees F with 90% relative humidity.
At the National Weather Service Hydrometeorological Prediction Center, one can enter data for this online heat index calculator:
“Meteorological Conversions and Calculations Heat Index Calculator”
http://www.hpc.ncep.noaa.gov/html/heatindex.shtml
To anticipate what those who wish to give the back of their hand to this paper would say: The above paper does *not* – I repeat, does *not* – say it’s “all or nothing”. We don’t actually need to see the average global temperature actually get as hot as they posited for their calculations to have such catastrophes. Long before it gets to the point when the average hot summer day is deadly to all mammals and birds, there will be a slow but sure increase over time of very bad heat waves approaching and then eventually reaching such catastrophic combinations of heat and humidity. The higher the average temperatures and water vapor levels, the hotter and more deadly the heat and humidity waves to humans, their companion animals, and all wildlife that needs to perspire to survive. (The probability is ever increasing that in a couple of centuries or so, the human civilization and warm-blooded wildlife in general we see in such places as Africa may not be possible – these parts of the world may be essentially dead, devoid of human civilization and such wildlife.)
Personal note: I have experienced a cooler version of such wet-bulb temperatures, and it was a scary experience. In the summer of 1998, while trying to enjoy the fresh air on the porch of a cottage next to the beach on the Gulf side of central-south Florida, the dry-bulb temperature on the porch thermometer read in the upper nineties F, and the humidity was horrendous. So much so, instead of the air from the fan making my skin feel cooler, it actually made it feel hotter, even much hotter and even painful – exactly as if the air was from a very hot blow dryer. Within a short time, I could not take it any more. I really believe that if I did not have an air conditioned area to retreat into or some water to submerge into, I eventually would have needed medical attention. (And yes, I was very well hydrated.) Even though I have lived in the heat and humidity of Florida all my life save one year in much cooler and dryer Southern California close to the Pacific coast, I have never before or after that time experienced such a terrible combination of heat and humidity. I do find it scary that such a terrible combination will (even if very slowly) become ever more severe and ever more common over the very long term.
It is beyond me that so many choose to deny the physics of evaporation, that there is such a thing as a heat and humidity combination such that it becomes physically impossible for evaporative cooling – physically impossible for heat loss via evaporation to happen fast enough to avoid injury and even death for mammals and birds. It is beyond me that so many choose to give the back of their hand to the ever increasing probability that such a terrible combination of heat and humidity will become ever more common and ever more severe, to the ever increasing probability that because of *wet-bulb* temperatures becoming too high for land mammals and birds in some parts of the planet, the next couple or so centuries will see essentially the end of most of the mammalian kingdom, the pinnacle of evolution, and even human civilization. (Human civilization is viable when some parts of the planet become uninhabitable due to heat waves becoming too deadly, never mind the same for the average hot summer day?)
KandA,
Yes, I’m interested to know how those who think we should simply get richer and richer and then adapt to whatever we might face, think we can adapt to wetbulb temperatures above 35oC. Airconditioning, maybe, but then you have to hope you don’t have a power failure.
Anders –
My guess is that even though they might agree with analyses that indicate such conditions are possible in the future, they won’t be able to address that possibility without exiting through the “alarmism,” or “adaptation” escape hatches.
Or, they will say that the chanc of ever realizing those conditions is remote, and therefore not worth a certain “economic suicide.” :-}
It will be interesting to see whether any of the resident “skeptics” will prove me wrong.
Jsam: http://www.skepticalscience.com/news.php?p=2&t=96&&n=124#7674
(‘I note you don’t seem to be nearly as assiduous on WhatWentWrongWithThat. I wonder why.’ Are you suggesting that there’s an equivalence between WUWT and SkS?)
Vinny,
I’m not entirely sure I’m getting your point. They could do better (sure) but it would take an army of people and lots of money? Fine, I’m sure that’s true but it still seems to be a site that provides lots of information and provides links to original sources.
Here’s a question/comment for you though. Climate change (from a policy perspective at least) is a risk issue. Do you agree? So, in a sense, we will always be highlighting the risks, rather than the possibility that nothing might happen – okay, basic physics tells us that “nothing might happen” is clearly wrong, so change that to “it might be fine” if you like. So, surely the discussion is always going to be about what could happen, how bad it might be, what we could do to avoid this, and what are the risks/costs associated with this.
So, the argument that SkS tends to present the bad things that might happen without presenting – enough in some people’s views – that it could be better than that, seems to be the wrong comparison. Maybe one could argue that they should also discuss what could be done and the risks/costs associated with that, but then they would be straying even into being policy prescriptive, rather than being policy relevant.
I guess my analogy would be that if you were deciding to get your car checked, you would be considering all the bad things that might happen if you don’t, you wouldn’t really be considering the possibility that nothing bad might happen.
I’ll add though, that in practice it should also include the risk of these things happening (i.e., how likely) rather than simply that they could happen.
anoilman: I am quite aware of what Vinny is seeking re a reference. My previous comment was addressed to you, not to him.
Along the lines of the risk analysis, a good analogy might be whether to earthquake-proof a building in say, central Wellington, NZ. They would consider the chance of a large earthquake happening there and when it might happen then weigh this up against the cost of earthquake-proofing the building. A good risk analysis will look at the worst case scenario, or so I would have thought. I also can’t imagine anyone would say, “People will be wealthier in the future so let’s let them earthquake-proof the building instead”.
ATTP: Yes, because it’s a risk issue we’ll always be more interested in bad impacts. I said that in one of my 2010 comments at SkS.
My objection to the pluses and minuses tabulation is that it’s an inept or insincere attempt at doing something that’s not worthwhile. Even if done with great diligence, the single study tabulation of impacts would be a waste of time because it could never present a fair picture of ‘What the science says’. Leave that to IPCC WGII. But SkS didn’t do it with great diligence and some of the contributions were (to use the dread phrase so beloved of the SkS tribe) cherry-picked for propagandistic ends.
It’s a pointless table done badly.
By the way, I was impressed by John Cook’s willingness to amend the table. I criticised the inclusion of four or five papers (to show that the table was silly). He removed all but one straight away and removed the last one a year or two later. Proof of personal sincerity.
But that doesn’t absolve the whole enterprise of insincerity.
(That car analogy hurts. I’m spending the weekend hunting for a new old car. The trouble is, I don’t really know how cars made after ~1995 work so I just have to hope that nothing bad happens. That approach failed with my current one.)
Vinny,
Possibly, but then we end up having a discussion about our opinions on whether it’s worthwhile or not.
I’m not quite sure what you mean by that or if it’s even a fair assessment. I’m not that interested in finding out.
Notice how we’ve skipped wordlessly over the shite about heatwaves to yet more nit-picking about SkS. But that’s what Vinny does – confect distractions out of belly-button fluff instead of facing up to the big picture.
What ‘insincerity’ Vinny? Care to demonstrate that for us? I want to see quotes that clearly show insincerity and I want ’em right now.
Can’t do it? Then post up saying you regret and withdraw the accusation of insincerity.
Vinny Burgoo: I have sent Graham Wayne an email asking for the source of the statement, “However, the same groups are also vulnerable to additional heat, and deaths attributable to heatwaves are expected to be approximately five times as great as winter deaths prevented.” made by him in the basic version of the SkS rebuttal article to the denier myth, “It’s not bad.”
http://www.skepticalscience.com/global-warming-positives-negatives.htm
It seems to me that some people are under the assumption that SKS is a poor source of information and not trustworthy but these same people never provide any evidence for this. If we are going to make accusations like these then can we please provide concrete reasons for them rather than this “she doesn’t shave her legs and armpits therefore I won’t trust what she says” nonsense.
I should add to my previous comment…if you can’t provide a good reason for why someone or something is not trustworthy – other than that they might be hippies and you don’t like hippies – then don’t say anything at all. It’s also off-topic and I’m in a bad mood.
> It seems to me that some people are under the assumption that SKS is a poor source of information and not trustworthy but these same people never provide any evidence […]
Even if providing evidence is possible, I’m not sure it would warrant peddling “but SkS” here.
“But alarmism” is no response to the fact that AT is not missing anything regarding Matt’s intellectual bankruptcy.
Vinny, I’d already enjoyed your word salad response on SkS. 🙂
You seem to fawn over WhatIsWrongWithThat and have no problems impugning others’ motives. http://wattsupwiththat.com/2009/10/24/climate-craziness-of-the-week-1/#comment-210712
Willard
Yes.
Yes.
Rachel Squirrel
Yes.
If I’m not mistaken, the “but Skeptical Science” branch of this discussion originated in my comment at November 13, 2014 at 2:38 pm (a quick search produces that as the first mention).
If so, I’m wondering if I have any rights of ownership over the branch? If so, since: (1) some of the ensuing discussion seem to reflect a misunderstanding of my point and, (2) I’m finding the quibbling about SkS to be same ol’ same ol,’ I’m wondering if I can call for an end to the SkS discussion?
🙂
Rachel – 🙂
Joshua: The SkS horse is already out of the barn.
But… alarmism! 🙂
But John, there’s way more horses in the stable.
There’s that old nag Whats Up With That… Do we really have time to list everything wrong over there? Especially with more mistakes being added by the hour, and censorship instead of corrections.
GWPF… Don’t say anything if you can’t say anything nice. Regarding the GWPF I’m speechless.
Back home here, we have the Friends of Science. A hilarious enterprise of random garbage. Here is the work of the head of public relations for the Fiends of Science. (Careful… put on a Mullet Proof Vest before you go.)
http://darkgreendevils.wordpress.com/author/darkgreendevils/
Nope… I’d take my chances with Skeptical Science. I bet fixing mistakes could be achieved in a matter of days. If I’d bothered.
Vinny… Here’s some cheap Reliant Robins they seem more your style;
http://www.carandclassic.co.uk/list/498/robin/
Here’s a video for those who are curious.
http://www.wimp.com/reliantrobin/
John Hartz: Thanks.
BBD: Big Picture? Carbon tax. (Incidentally, I can’t recall you – or most of the regulars here – ever proposing concrete measures to mitigate climate change. Do you have any concrete proposals beyond bashing people who get the science wrong?)
BBD: Insincerity? Yes, that’s my impression. Like it or lump it.
Rachel: Hippie-bashing? Moi? (Actually, I don’t think I was on this occasion, but never mind.)
jsam: Fawning? Prove it! I want to see quotes that clearly show fawning and I want ’em right now.
Cheap? I just missed a Nissan Micra that was going for £350.
Vinny, you’re able to see insincerity in Sceptical Science but not in The Daily Mail?
However valid your point may be about that one particular Sceptical Science reference your concerns do get rather swamped by an induced wave of incredulity. For someone who states that the IPCC failed to achieve objectivity you do seem remarkably accepting of some startlingly unobjective stuff.
Vinny Burgoo: Here is Graham Wayne’s response to my querry.
I believe I was summarising “An Evaluation of Climate/Mortality Relationships in Large U.S. Cities and the Possible Impacts of a Climate Change”, Laurence S. Kalkstein and J. Scott Greene, Center for Climatic Research, Department of Geography, University of Oklahoma (attached).
Here are the salient figures, quoted from the results section: “However, the 100-200 death drop in winter mortality is much less than the large increases of 1,300 to almost 3,000 deaths in summer mortality under the 2050 scenarios”.
As you can see, I weighted my approximation to be as even-handed (un-alarmist) as possible i.e. I used the best case figure for heat deaths prevented (200), and the best case for cold deaths caused (1300) – and then I lowered the ratio to 1:5 to be even less dramatic although the real ratio is more like 1:6.5. The other figures for each case would make the ratio 1:30!!!
if you wish to discuss this matter further, I suggest that we do so on the comment thread to the SkS article in question.
Good job John. Its really smart to ask the people who know.
Vinny
Not good enough. I asked for a demonstration supported by quotes. Stuff your opinion. You’ve been caught making a baseless accusation. The decent thing to do would be to apologise and withdraw it, as you know perfectly well.
John Hartz
Thanks for the clarification.
Pekka
To reconnect with the theme of ‘what am I missing?’ I was tempted to reference Hansen, Sato & Ruedy (2013) earlier:
I know you have reservations about this study which you set out in a previous conversation at JC’s but I cannot find our exchange. If you have five minutes, I’d be grateful if you would recap your argument again here. I didn’t fully understand it, so I’m hoping others will chip in and bring clarity. Not to mention a bit of science to leaven the same ol’, same ol’.
BBD,
The problem is that they made a serious technical error that was first pointed out by Tamino. For some reason he has, however, removed those two posts and threads, where this was discussed (I cannot avoid having some suspicions about the reason, as all other threads of the same month seem to be still available). Significantly later a journal article written by some other scientist has also been published, where this error is also explained, but I don’t find that paper from my files, and don’t remember, where it was published. Steve Mosher has claimed in the Climate Etc discussion that Hansen has accepted the error, but I have not seen that confirmed elsewhere.
The error was so serious that essentially everything that might be consider scientifically new in the paper was false. This is based on the interpretation that the broadening of the temperature distribution could have been considered a new scientific result. More or less all graphics shown in the paper is also related to this result including those presenting maps.
The technical error is related to the fact that the change of a local temperature over some interval can be divided into three parts:
1) the change in the average local temperature
2) the deviation of the initial actual temperature from the initial average
3) the deviation of the final actual temperature from the final average
The first contribution varies from place to place due to effects like Arctic amplification, distance from oceans, and many other regional or local differences. The analysis combined all local temperature changes to a single distribution. Thus the apparent variability of the later temperature had a large contribution from the spatial variability of the change in mean temperature. It’s difficult (or impossible with the amount of data available) to estimate accurately the shares of each type of contribution to the variability in the local temperature changes, but very rough estimates indicate that all of the broadening may result from this effect. Most certainly the results of the paper have no evidential power that would justify their conclusions.
It’s virtually certain that extremely high temperatures rise at least nearly as much as the average temperatures, but the paper can actually not tell even that, we just believe that that’s true based on simple common sense reasoning.
It’s virtually certain that the method that the paper applied could be reversed to indicate that the temperatures of the past had a larger variability than later temperatures. That would require only that the most recent period would be chosen as the base period and the past temperatures would be compared to that.
Using Google Scholar I found the paper I mentioned. That’s written by Rhines and Huybers.
I found also an answer by the original authors. I’m really amazed by that. The skip the main point of the criticism and answer to minor additional comments that Rhines and Huybers presented. It seems that they still do not understand, how seriously wrong their method is.
Vinny: Fawning? Yes, that’s my impression. Like it or lump it.
Pekka
Thanks for this.
If Tamino was correct, this is interesting (paging Vinny) but then there’s the WMO Global Climate 2001 – 2010 Report. pdf p.8 -9.
BBD,
I should perhaps emphasize once more that I see the issue so serious mainly from the point of view of scientific value of the paper. Whether it’s significant for the more general understanding of climate depends on the level of understanding that’s being considered. (Not significant at lower level, but increasingly when expertize increases.)
Getting statistically significant results on extreme weather is really difficult. By definition extremes are rare, and experience tells that the tails of the probability distributions are almost certainly fat. A distribution with fat tails has so many uncertain parameters that fixing them requires a lot of data. Some typical distributions with power law tails produce new surprises for ever. What may have seemed as the most extreme event possible, may suddenly be exceeded by a significant amount without any change in the actual probability distribution.
This is one more and a more extreme example of the fact that we get strong confirmation about changes in climate only when the changes are have already been large for long and bound to strengthen in the future.
When the average temperature has gone up by one degree, the heat waves are also typically hotter by one degree. In some areas local conditions may amplify the effect and in some places the extra degree leads to worsening drought from evaporation. More generally I do not believe that the temperature effects are significantly nonlinear until the warming gets more strong.
Pekka
Would you agree that observations are broadly in agreement with HSR13?
That depends on what’s the observation. If it’s something that requires that extreme highs change significantly more more than the average, I do not agree that real evidence exists.
One plausible idea is that the unusual state of the equatorial Pacific is related to recent weather extremes, but the causes of this state can only be speculated.
Pekka
I’m having trouble reconciling this with the observations WMO 2001 – 2010 (p8 – 9).
And then there’s Australia’s ‘angry summer’ of 2013.
And the Chinese heat wave of 2013.
Sorry Chinese heat wave of 2013.
In the best case one factor can explain several events, but not all. It may, however, enough influence to distort some statistical measures.
The main problem remains that determining the statistical significance is not possible. It’s surely not very strong, but is it any significance?
Pekka
I leave it to you to decide whether the Hansen paper is supported or contradicted by observations.
In the beginning of this post, I give a number of links to good information about The climate dice paper. Short: it did not study whether variability is increasing. Many people, quite naturally thought it did, and pointed out that the method may not be suited for that. The main reason that the distribution gets broader is not that the variability is increasing, but that the mean changes differently in different regions.
Pekka, are these the Tamino posts you thought had been removed?
Tamino’s argument seems sound to me, as well as Pekka’s and Victor’s summaries above.
Here’s a more detailed Tamino post on temperature variability.
DS,
They seem to be the same posts.
I looked for those posts a couple of months ago carefully. I knew the time accurately, because I found Climate Etc discussion, where they were referred to, but I didn’t find these posts. Good to see that they can be found now.
I just archived them using archive.today and web.archive.org in case they disappear. It wouldn’t be the first time. Tamino’s had to delete some posts before because WordPress.com caved in to legal threats from a commenter who objected to Tamino’s responses being inserted into his comment. (Oh, the horror!)
I only found those Tamino posts because I’d repeatedly advertised them on the Climate Literacy Network after noticing the climate dice paper being used as proof of increased variability.
One more comment on what I meant in stating that it’s impossible to separate the effects of temporal variability and spatial variability based on the existing data. The 2013 paper of Hansen et al shows in Fig. P1 the distributions for NH, SH, and [contiguous] US stating that they are scaled by “local SD”. They notice that the US distribution is very noisy, but even the contiguous US has quite a lot of spatial variability. It leads, however, to very noisy results. Going down to sufficient locality to remove the spatial component makes the curves too noisy for telling anything.
The traditional way of looking at the temperature changes is to show the changes in temperature units. What Hansen et al have added is a highly questionable way of expressing the changes relative to a SD. My view is that this is only misleading and confusing. We have seen many skeptics inventing misleading presentations that they use to “prove” that nothing has happened, I see these papers as a mirror image of that in their attempt to make the changes to give a stronger impression than well understood and valid approaches give.
Exceptional heat waves have occurred in the past (like the dust bowl of the 1930s). They may require some special pattern in circulation. The 2013 paper of Hansen et al mentions the La Niña as well. From statistical point of view events that are controlled by a single pattern are among those where statistical power builds up really slowly. The whole book Nassim Taleb: The Black Swan and some books of Mandelbrot are based on the importance of this observation.
Global warming may have contributed to these events more than just by rising the base temperature, but the observations alone cannot add much to the posterior likelihood of that based on Bayesian analysis. What would add much more to the evidence were a GCM verified as skillful for regional analysis that links the issues together, but unfortunately we do not have such models.
Speaking of whom:
DumbSci – thanks very much for the Tamino links. In conjunction with Pekka’s explanation, the reasons for disagreement about HSR12 are now much clearer to me.
It’s also clear from the WMO Report and heatwaves post-2010 that extreme hot summer events are on the increase, which is the point I wanted to illustrate for Vinny. Who, I note, has still not apologised for his baseless slur against SkS.
Eh… HSR13 not 12.
Pekka Pirilä, it is perfectly possible to distinguish between changes in spatial and temporal variability. In the post I linked above, Reinhard Böhm studied just the temporal variability. (Does someone know of an article on changes in the spatial variability, somehow does not seem to be popular.) The Hansen “climate dice” paper just did not do so.
It is perfectly permissible to normalise the time series before studying trends. The year to year variability in the tropics is smaller than this variability around the poles. Thus the same absolute change in temperature (in °C) would likely have more influence in the tropics as in the polar regions. The (eco-)system in polar regions are likely adapted to be able to handle more variability.
Victor, changes in spatial variability are inherent in papers which look at the spatial range of correlations in temperature (starts with the early Hanson and Lacis(?) one from about 1980 which set the range for GISSTEMP extrapolations. There is an interesting one out there that shows that the range is season dependent.
Victor,
I didn’t tell fully, what I had in mind. I was actually thinking on separating three components
– spatial variability
– temporal variability of the mean temperature
– variability around the mean
All the three should be considered, to draw conclusions about the third, and that’s one too many without more data.
Eli, if their aim was to look at how far one could extrapolate, did they then not just look at the spatial correlation function. You would not need information on how that changes over the years for that. If they really studied changes and it is easy for you to find, I would be interested in a reference.
Pekka, also the spatial variability could be separated in variations in the mean and variability around the mean, which I would prefer in such a case for symmetry. I see no fundamental problem doing such a thing. In a large ensemble of fields this would be effortless. The problem in practice is that reality only has one realisation. Thus we need to decide what is variability around the mean and what is the variability of the mean. That takes a somewhat arbitrary cut off frequency/scale. Böhm took 30 years.
Victor,
You explained the arguments that I have in mind. I don’t believe that it’s presently possible to get unique enough results from that approach. That’s the reason for my view that more good quality data would be needed.
Victor and ATTP,
I can’t speak for the energy budget approach, and this obviously doesn’t address concerns about non-linearity, but I recently estimated TCR using a Bayesian regression model with standard noninformative priors. The posterior distributions that result from three different temperature reconstructions, 1) HadCRUT4, 2) Cowtan and Way (CW2014) and 3) GISTEMP are shown here.
The mean estimates (and 95% credible intervals) are:
HadCRUT4 -> 1.5 °C (1.4–1.7 °C)
CW2014 -> 1.6 °C (1.4–1.8 °C)
GISTEMP -> 1.7 °C (1.5–1.9 °C)
Grant,
Thanks. You may be interested in the recent Cawley et al. (2015) paper which says
It’s a response Craig Loehle’s recent curve fitting paper but uses a simple forcings-based model with a exponential delay timescale to determine the TCR. I may write something about it if I get chance and have the energy 🙂
Pekka, how would more data help for this problem?
Grant McDermott, good to see that is does not matter that much. That could otherwise been a sentence in the Nic Lewis article: we found that the different datasets gave almost the same answer as the one we used. If you have a computationally intensive model run, you may have an excuse for not trying multiple models/datasets, but not if it is that easy to try and report.
More data is always needed if the desired response is to wait.
jsam: My sentiments exactly. Time is not on our side.
Victor,
A longer period would probably help most, but some help could come also from more stations taking into account not only the distances from other stations, but also various other attributes that might affect the rate of warming.
The more of the variability can be explained by a statistical model built on plausible contributing variables the better it’s possible to determine the extent of “random” variability. The variability that can be explained by likely causal dependencies may also contribute to deviations from the mean.
Pekka, you would still have to make an arbitrary distinction between the variability you see as changes in the mean and the variability around that mean at smaller scales. Otherwise, I would love to have better data (there are likely strong non-climatic changes in the variability around the mean, they are expected to be worse than the non-climatic changes in the mean).
Maybe you are thinking of completely different studies than I am.
Thanks ATTP, I’ll definitely take a look at the Cawley study.
….
Some people on the thread are already be aware of this, but the TCR estimates that I give above are from a revised working paper of mine: “Sceptic priors and climate change mitigation“. The main idea of the paper is to use a simple Bayesian framework in determining how strong sceptic beliefs need to be, before someone is unwilling to do anything about climate change. (Short answer: Very strong, indeed.)
I’d welcome any feedback from those who are interested in looking over it.
Grant McDermott says: “The main idea of the paper is to use a simple Bayesian framework in determining how strong sceptic beliefs need to be, before someone is unwilling to do anything about climate change.”
I hope you will formulate that more neutral in your paper. It is possible to be confident that climate change exists, but to like the consequences of climate change and if you are willing to say so in public to claim you are not convinced by the science yet.
Thanks Victor. I do try to state it more neutrally in the paper. Still, that’s the sort of feedback that I’m more than willing to hear 🙂