Exxon speaks

devils Everyone is being terribly cwuel to Exxon, and they feel the need to respond. You can probably chalk that up as a success, though a minor one. On the ultimate substance I don’t feel any need to revise my previous posts: that Exxon’s climate science research was far less interesting than the stories are trying to say; that it wasn’t secret, but indeed clearly public; and that it didn’t give them any special insight that wasn’t widely available to everyone else.

* What Exxon Knew and When?
* What Exxon Knew and When, round three?
* What I said about Exxon

However, the flipside of that is that Exxon did spend years when run by Lee Raymond spreading FUD on GW. Since Rex Tillerson took over they’ve been rather better. But for reasons of their own – company culture, reluctance to admit mistakes, or because LR still has his hand on RT’s testicles, who knows – they can’t bring themselves to say that the change in CEO made for a change in policy. Perhaps its embarrassing that just one person’s opinions count for so much in a company that perhaps prides itself on an engineering, fact-based culture. I don’t know.

So when Exxon say that media and environmental activists’ allegations about the company’s climate research are inaccurate and deliberately misleading I agree. But when they continue For nearly 40 years we have supported development of climate science in partnership with governments and academic institutions, and did and continue to do that work in an open and transparent way then I demur; because it glosses over their campaign of FUD, some of which was open and transparent (they published stuff in the shareholders newsletter, for example) and some was (and probably still is) distinctly non-transparent (funding dubious denialist think tanks). They don’t ignore this entirely; they can bring themselves to say We recognize that our past participation in broad coalitions that opposed ineffective climate policies subjects us to criticism by climate activist groups but suggesting that their campaigns were limited to opposing ineffective policies is dishonest.

Exxon’s Activists deliberately cherry-picked statements attributed to various company employees to wrongly suggest definitive conclusions were reached decades ago by company researchers. These activists took those statements out of context and ignored other readily available statements demonstrating that our researchers recognized the developing nature of climate science at the time which, in fact, mirrored global understanding is correct. But The facts are that we identified the potential risks of climate change and have taken the issue very seriously isn’t; except when very carefully interpreted. They “took the issue seriously” in the sense that they realised it was a threat to their business model. But the FUD wasn’t an honest response.

Since 2009, the company has supported a revenue-neutral carbon tax is nice; but I think their “support” has been weak. It is their policy, but they don’t push it hard; they don’t campaign for it.

[Financial disclosure: I’m sure I’ve said this somewhere years ago (and this text is copied from the “round three” post), but I can’t find it and I doubt anyone else can: I don’t own any Exxon shares or have any direct financial interest but my parents in law worked for them, and I have received proceeds from Exxon shares. AFAIK Exxon themselves haven’t read this post, and certainly aren’t paying me for it.]


* Climate Denial Crock of the Week with Peter Sinclair: Prison for Exxon Execs?
* Tamino: Whack-a-Mole
* What did ExxonMobil Know and when did they know it? (Part 1) David Middleton at WUWT. Astonishingly and disturbingly I find myself in agreement. Not only does he get this mostly right, he fails to over-egg his pudding significantly. Part 2 doesn’t add much.
* How Exxon went from leader to skeptic on climate change research – LA Times. This is close to balanced; certainly the best meeja presentation I’ve seen. Notice that they report that in 1988 Exxon urged a “balanced scientific approach”.
* Exxon Knew about Climate Change Almost 40 Years Ago – Unscientific USanian; poor.
* Exxon Mobil Investigated for Possible Climate Change Lies by New York Attorney General
* [2019/05] Don’t be misled by news reports. WATCH to learn the real story behind #ExxonKnew – twit by Exxon pointing you at https://corporate.exxonmobil.com/en/Energy-and-environment/Environmental-protection/Climate-change.

Joan Crawford has risen from the grave!

joan As it says in the good book:

Junkies down in Brooklyn are going crazy
They’re laughing just like hungry dogs in the street
Policemen are hiding behind the skirts of little girls
Their eyes have turned the color of frozen meat

No, no, no, no, no, no, no, no, no, no, no, no
Joan Crawford has risen from the grave
Joan Crawford has risen from the grave

Catholic school girls have thrown away their mascara
They chain themselves to the axles of big Mac trucks
The sky is filled with hordes of shimmering angels
The fat lady laughs, “Gentlemen, start your trucks”

Oh no, no, no, no, no, no, no, no, no, no, no
Joan Crawford has risen from the grave
Joan Crawford has risen from the grave

[I’ve made a couple of corrections to the lyrics] Or, put another way, the current status of Hansen et al. is Status: final response (author comments only). Rumour has it that ACP’s online system switches to “Final publication not foreseen” when a certain amount of time has elapsed without the authors replying to all open-discussion comments and the editor making a decision.

I’m a bit surprised, because some of H’s comments looked, as I said, like the responses of someone who’d given up. But not yet, it seems.

[2016/2/28: The monster lives. But, is it the same monster?]

Sea ice: the triumph of the William

This year’s sea ice was unexciting. NOAA goes for “2015 Arctic sea ice fourth lowest on record” which is doubtless true.

Tamino has some helpful plots, so I’ve nicked one. I’m pleased that my 2014 comment “Hopefully that too [i.e., 2012] will look like an outlier in years to come” now looks quite true. From a statistical point of view, Tamino says “changepoint analysis can only confirm one rate change, but a smooth suggests more might be going on”; and I’m sure that’s true from that view. From a physical viewpoint I’m less convinced, and would just take a simple LS fit to the whole (satellite) series. A continued long-term decline is the obvious prediction.

Speaking of which, we come to the topic of this post, my bet with CR, recorded here, formalised here, which is:

Crandles offers 3 separate bets on the [monthly average extent not area] average of [2012, 2013 and 2014] (to be above/below 4.294, I take the high side), of [2013, 2014 and 2015] (4.119, ditto) and of [2014, 2015 and 2016] (3.94, ditto). In the event of anything that clearly throws things out like a VEI6 volcanic eruption bets are voidable.

And the data shows:

year mo    data_type region extent   area   avg
2012  9      Goddard      N   3.63   2.15
2013  9      Goddard      N   5.35   3.74
2014  9      Goddard      N   5.28   3.70   4.75         (2012-14)
2015  9      NRTSI-G      N   4.63   3.31   5.08         (2013-15)
2016                          2 - X         3.97 - X/3   (2014-16)

(note: 2013 was also 5.35 extent in NRTSI, but 3.48 in area. Which shows what a good idea extent is). So I win (hurrah!) and for extra bonus points, as CR notes by email, sea ice extent has to be implausibly low – less that 2 – in 2016 for him to win; so for a £10 concession for early payment, we’ve settled the last one, too.

I believe (see Sea ice betting report wherein Neven unwisely converted his E50 win in 2012 into double-or-quits for 2013-15, that he now owes me… oh, yes, nothing. Because he won last time, so we’re quits :-).

So what if anything does this mean? Or, in CR’s terms, Were you just lucky or skillful? Most of my thinking (as I said before somewhere, I’m sure) was based on a Impact of instantaneous sea ice removal in a coupled general circulation model by D. Schröder (who did the work) and W. M. Connolley (who did something). Which showed – at least in a model – that the sea ice really isn’t very sensitive to sudden loss; there is no tipping point; if you strip off the ice it recovers quickly, in a few years. To reduce the sea ice you need years of increasing forcing leading to less ice. Which, over the long term, we’ll have I think. But it means I think that 2007 – and then 2012 – were less important than other people thought (see some quotes from 2008). However… it wouldn’t like to over-emphasise that. Who knows what future years will bring?

Hansen et al.: RIP

[Update: Or, maybe not.]

Via twitter comes news of the sad demise of “Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming is highly dangerous”; Review status: This discussion paper has been under review for the journal Atmospheric Chemistry and Physics (ACP). A final paper in ACP is not foreseen. My view at the end of August was that Peter Thorne’s review was “substantially negative about the paper”; it looks like the editor has gone with that and similar views. In essence, its a sad train-wreck; only read on if you like such. I feel somewhat cruel in even blogging it. But Hansen is a big boy, and he chose to put this up in public.

First, timing. I’ve now re-read Eli Follows Up written on the 12th of October (a successor to the critically acclaimed Eli follows through) which tells me that “The editor, Frank Dentener, has closed the open discussion and thrown the paper into the second stage of review… The authors are now expected to publish responses to the comments and reviews”. Which explains the flurry of replies by H on the 13th. In consideration of the review by Drijfhout et al., “Eli judge[d] that the editor will pay serious attention to these arguments and Hansen, et al, will have to meet their challenges”.

But before we get to that, let’s look at a comment by Greg Flato, another serious player. Its not new, but had slipped my attention in the mass of other comments. Its probably the most critical of all – ignoring the nutters, of course.

given the way the paper is organized, it is difficult for a reader to connect assumptions made in the model forcing (sections 3.2 and 4.3) to their justification based on paleo-climate reconstructions (section 2.1) and modern observations (section 7.3). What is important is that the prescribed freshwater forcing scenarios have an exponentially increasing form with doubling times of 5, 10 and 20 years. The most extreme of these has sea level rising 5m by the year 2060. This assumes freshwater flux could rapidly reach values up to 8Sv. To put this in perspective, it is about 1800 times the currently observed melt rate for west Antarctica… Prolonged exponentially increasing ice-sheet loss is clearly unphysical and so the authors arbitrarily terminate freshwater input once the associated sea-level rise reaches 5m – it is zero thereafter… The authors provide no assessment of the likelihood of any of their scenarios, and do not cite most of the previous studies that have explored the response of the climate system to much less dramatic freshwater input… They also do not justify the manner in which this freshwater is introduced into the ocean (as liquid water with a temperature of -15◦C, pg. 20079)… simulated global temperature drops to roughly 1.4◦C below preindustrial levels… This is in striking contrast to essentially all published projections of 21st century climate change, and so places a very large burden on the authors to provide evidence in support of rapid global cooling in the face of rising greenhouse gas concentrations…

Adding the melt to the ocean as water at -15 oC is a “WTF?” moment. Also Flato points out, somewhat more diplomatically, what I said before: hosing is passe, its been done to death. So how do H et al. respond? In a rather long rambly sort of way that ends up with “In all of these model runs we used -15°C as the temperature of the freshwater added to the ocean mixed layer. If a large fraction of the ice sheet discharge is icebergs, the cooling effect would be larger than in our experiments”. So I think the point is that the latent-heat equivalent of dropping the ice in the ocean and having it melt, would be inserting the ice as water at -15 oC. Except, it wouldn’t be: -15 is just a nice round number, as H implies in the reply, actually it should be a different number. Um. And none of this info is in the original paper? I think we’re back at my suggestion: the paper is too long, and clearly needs to be broken up into sub-papers that are manageable.

And… H et al. just won’t learn: having been criticised pretty strongly for mixing science and advocacy, the end of the response to Flato is Let us hope that we are smart enough not to perform an empirical test using the real world with a forcing of the business-as-usual magnitude. Really? Does say to him “please, just don’t say that, this isn’t the place”? I’m speaking as a famously diplomatic person, you understand.

But the make-or-break one is Drijfhout et al.: are six people enough to stand up to Hansen? Well, yes. They start off fairly gently with The analysis does not contain any process that is physically impossible (albeit sometimes unlikely)), nor present principally flawed interpretations of the paleo data (albeit often biased to the upper end of uncertainty measures) but fairly soon get to

The title of the paper is more suggestive than is justified by the scientific evidence. The conclusions
cannot be regarded as being robust, as they are insufficiently supported by both modeling results
and observations

which is fatal. H et al.’s response is very short, and is the reply of someone who has given up. The most obvious example of this is

Extreme events are much more likely to occur after 2100 – therefore we recommend to avoid terminology such as “dangerous”. Hmm, yes, I guess that we should not be concerned about anything that happens 85 years from now – the dickens with those characters. The Dutch can migrate to Switzerland, after all.

If you’re going to write that kind of thing, stick to blogs and op-eds.


* “Unfortunately, while computers continually surprise us with what they can be used for, almost nothing is known about what they cannot do.” – via QS
* Science Isn’t Broken: It’s just a hell of a lot harder than we give it credit for. Includes nice p-hacking toy.

Frances, top weatherman

It (it? Philippe Verdier, possibly-ex-weatherman) is all a bit silly, but here’s a snapshot from the Torygraph if you like. Its the same old stuff: We are hostage to a planetary scandal over climate change – a war machine whose aim is to keep us in fear… I received a letter telling me not to come. I’m in shock… This is a direct extension of what I say in my book, namely that any contrary views must be eliminated. Apparently the IPCC “blatantly erased” data that was contrary to their conclusions. Yawn. [Update: yup, definitely ex.]

Oh, the picture? That’s from The Wildlife Photographer Of The Year 2015 (or direct). As in 2014 the judges clearly picked the wrong best pic.

Far more interesting are rumours of aliens around a distant star but, fun though it is while it lasts, its going to turn out to be mundane. Though it does have echoes of the intro chapters of a couple (couple? Many) sci-fi novels I’ve read. [See-also: Dynamics of CATS.]

Back to the less interesting, Tamino has another in the Exxon series; this one features Congress critters.

Far more interesting is Timmy (well, and some of BP’s words; you can read them direct if you’re ideologically opposed to Forbes) on fracking and its impact on the oil industry:

worries over climate change mean that we’re most unlikely, in any reasonable period of time at least, to use all of those reserves and resources that we already know about… oil is not a resource that is going to run out. It does not therefore become ever more expensive off into the future. But it’s fracking that is the real game changer here… The standard economic description of the oil market is one where both demand and supply are inelastic… Inelastic supply meeting inelastic demand means wild price swings. It’s this that fracking changes… it isn’t really a natural resource extraction method… it is a manufacturing process… As you know, the strength of manufacturing productivity has led to a trend decline in the prices of goods relative to services. A fascinating question raised by fracking – and its manufacturing-type characteristics – is whether it will have the same impact on the relative price of oil… The net effect of all of this is that we should expect oil to be much less variable in price in the future. And we should also expect it to be going down in price into the future.

With some interesting caveats re the shale producer’s exposure to finance costs, and speculation about the role of current low interest rates. And the interesting observation that It is inconceivable that the reduced dependency of the US on oil imports won’t affect its relationship with some of the key oil producers; and the revere, on China’s part?


* Hersham boys
* Two pints of lager and a packet of crisps, please
* The Lone Ranger – I’d forgotten, as wiki says, some fragments of lyrics were deemed to have “drug” and “homosexual” references – errm, well, its a bit stronger than “deemed”.
* December will be magic again with LOL cats.
* The Economic Proof That The FDA’s Drug Regulation Makes Us All Poorer – Timmy

Wikipedia:Categories for discussion/Log/2015 October 6

A more than unusually obscure headline perhaps. Here’s the link. I noticed, because my watchlist contained a pile of changes like:

(diff | hist) . . mb Nir Shaviv‎; 23:31:54 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Henrik Svensmark‎; 23:31:53 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Jan Veizer‎; 23:31:50 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Antonino Zichichi‎; 23:31:49 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Philip Stott‎; 23:31:48 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Willie Soon‎; 23:31:47 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Roy Spencer (scientist)‎; 23:31:45 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Frederick Seitz‎; 23:31:44 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers (scientists) per CFD at Wikipedia:Categories for discussion/Log/2015 October 6.) [rollback]
(diff | hist) . . mb Timothy Ball‎; 23:31:35 . . (-1)‎ . . ‎Cydebot (talk | contribs)‎ (Robot – Moving category Climate change skeptics (scientists) to Category:Climate change deniers
…and so on…

The proposal was that the Category “Climate change skeptics” should be renamed “Climate change deniers”, and the Nominator’s rationale was I think we are at the point to where it is unacceptable to claim that it is skepticism. Everyone should be skeptical as a part of good science. But climate change deniers are not engaging in scientific skepticism, but rather political rhetoric and ideology. I think we are far behind in letting this stand this long. Interestingly, neither the nominator, nor any of those who voted, are in the “usual suspects” category either way. They also proposed renaming “Climate change skeptics (politicians)” –> “Climate change deniers (politicians)” and “Climate change skeptics (scientists)” –> “Climate change deniers (scientists)“, which is what you’re seeing above.

Ever so slightly confusingly, a few months earlier the category “Climate change skepticism” got moved to “Climate change skepticism and denial”. That one was somewhat more controversial.

Meanwhile, on Talk:Climate change denial, they are pondering the question Should climate change skepticism, and similar redirects, point to this article, or to Global warming controversy? (Actually that’s not quite the question any more, but you get the idea).

And so it begins…

Via DA, rawstory, the Beeb reports Alaska mulls extra oil drilling to cope with climate change:

Expanding the search for oil is necessary to pay for the damage caused by climate change, the Governor of Alaska has told the BBC. The state is suffering significant climate impacts from rising seas forcing the relocation of remote villages. Governor Bill Walker says that coping with these changes is hugely expensive. He wants to “urgently” drill in the protected lands of the Arctic National Wilderness Refuge to fund them.

And so on. This kind of stupidity is, sadly, inevitable, though I am surprised by the lack of reflection from the Alaskan governor. I’d kind of at least expect a bit of “this may seem self defeating but…”. In this case there appears to be an obvious alternative: just let the seas wash higher; as is being done in East Anglia where the coastline is sinking due to isostatic rebound (can’t find a good link; perhaps this). But in summer people will turn the A/C up…


* Mitigating Climate Change–$1 Million Relocation Per Family

It could have endorsed sensible policies…

Oreskes is re-hashing the Exxon stuff again, how very dull-man-at-a-party of her. So, I won’t join her in re-hashing the reasons that much of what she is saying is wrong. But my attention was drawn to my titular sentence, where “sensible policies” was linked but – how modestly – she refrained from pointing out that those very sensible policies were ones that she herself0 was proposing: The climate responsibilities of industrial carbon producers, Essay, Climatic Change, September 2015, Volume 132, Issue 2, pp 157-171.

I won’t bore you with the details but essentially the situation is unchanged: global warming is still all someone else’s fault. Not you, not I, who drive the cars that burn the petrol and live in the houses heated with fossil fuels. No! The fault is all down to the Evil Fossil Fuel Companies who force us to use their evil products, much in the way that cigarette companies once forced people to smoke even while the surgeon-general told them to stop. This is the same confusion of responsibility at Fossil fuels subsidised by $10m a minute, says IMF? – the people responsible for emitting most of the CO2 are consumers like you and I, not the fossil fuel producers.

To state the bleedin’ obvious: people know that fossil fuel emissions cause global warming. People know perfectly well that the IPCC, and various scientific organisations, are telling them the truth; and they know that the various denial-o-sphere organisations are lying to them. Just like they knew the surgeon-general was telling them the truth about smoking being bad for them, and they knew then fag1 companies were lying. For various exciting reasons including but not limited to human psychology, that doesn’t affect people’s behaviour as much as you’d like it to. It is possible that if, as Oreskes suggests, companies unequivocally communicate to the public, shareholders, and policymakers the climate risks resulting from continued use of their products, and therefore the need for restrictions on greenhouse gas emissions consistent with the 2 °C global temperature target; [and] firmly reject contrary claims by industry trade associations and lobbying groups then it might even make a difference. People do, generally, need an excuse to lie to themselves; its helpful to latch on to someone external lying to you; you can always blame them later when it goes pear-shaped.

Constantly whinging about fossil-fuel producers lobbying against CO2 restraint; or even complaining about them lying, is to my mind all rather beyond the point. You expect them to do it; its hardly a shock. We should be able to cope. If our politics is so rubbish that lies from entirely predictable sources causes it to malfunction, then the real problem is our politics, which again is sourced back to the populace.

Oreskes discussion of responsibility is remarkably unthinking. Starting at section 2, “What is responsibility?”, it salivates over lawsuits but takes corporate responsibility itself for granted, and doesn’t even consider the consumers at all.

[Update: oh yes. I also forgot to say that I object to her very first sentence: Responsibility for climate change lies at the heart of societal debate over actions to address it. I don’t mind people being interested in who was responsible, but I don’t think it should be a big focus of the debate, because it gets in the way of solving the problem. If you start with “right, who is responsible then?” everyone starts getting defensive.]


0. Update: actually, the authors are Peter C. Frumhoff & Richard Heede & Naomi Oreskes.

1. In the Olde Worlde, a “fag” is a cigarette. Not a woofter.

Force F from outer space

tf Most normal people would have been content to have produced one game-changing theory of climate but David Evans is not a normal person. No! He has squillions of degrees from Really Prestigious universities and has, on his own, invented entire new types of Fourier analysis. So it is with no surprise – rather, with a dull grey sense of the inevitable – that I note (thank you JM and ATTP) that his latest theory has thunked onto the doormat like junk mail. ATTP attempts to make some sense of DE’s confusion over partial derivatives – they’re the work of the devil I tell you – and I’ll try to point out the more obvious errors in New Science 7: Rerouting Feedback in Climate Models.

Let’s start with the first sentence: All the establishment models assume carbon dioxide warms the sky, which leads to the surface warming. Which is wrong. To be fair, those aren’t the brilliant DE’s words, they come from the only-somewhat-less-brilliant-as-the-moon-is-outshone-by-the-sun Jo Nova as an intro. In this case she it is not entirely clear that she has parsed correctly, because the actual article starts In post 5 we noted that the architecture of the conventional model only allows feedbacks that are responses to surface warming, thereby omitting any feedbacks that are primarily in response to climate drivers. So whether their nonsense is upside down or not I don’t know, but either way up its just wrong. So I suppose I need to read part 5. Which contains stuff like The conventional basic model assumes, is built on the idea that nothing causes changes to Earth’s climate unless it works through surface heating — and the GCMs have the same architecture. Cloud cover does not change ice cover. Ocean currents don’t change cloud cover. Changes in biology don’t change clouds. Only changes in surface temperature changes cloud cover. This is so wrong its hard to know where to start. He continues When feedbacks were introduced to the conventional model (see post 3), they are applied to the surface temperature but not the climate drivers so I suppose I need to read part 3. They are very proud of part 3: A feast. A feast! For those who want the meat, the math and the diagrams says JN; Here is the conventional basic climate model, in full says DE. And its all very sad. And I really do mean that. In the sense I’ve tried to explain at “Dr” Roy Spencer is sad and lonely and wrong. These are intelligent people saying very silly things, because they have no-one to talk to who has a clue. And the reason they don’t talk to people who have a clue is (a) because they’ve alienated all such; and (b) they would refuse to talk to them if offered the chance. [Update: Nick Stokes has a nice example.] DE wants to talk about G = (absorbed solar radiation) – (outgoing longwave radiation), which is dead exciting, and he puts up an equation.

jn-again Isn’t it a nice equation? Its got partial derivatives ‘n’ all. Probably, its part of his partial derivative confusion. But, its got nothing at all to do with how GCMs work. So I don’t think there’s any point going any further with the wrongness; I’ll attempt to explain The Truth and see if it helps; because likely other people don’t understand this either. I find I’ve touched on this before – in 2013 – but didn’t really make it clear, unless you already know it. So I’ll try harder.

Emergent versus imposed properties

An example, from the game of Go, on the off chance that you play it so might understand. In Go, you place stones on the board and try to surround territory, and kill your opponents stones. A group of stones can be finally killed – notice that I’ve elided detail there – when the stones forming the group have no liberties left. This leads to the concept of a group being “alive” when it has two “eyes” – non-removable internal liberties. Lots of play, and lots of the fighting, centers around forming or removing eyes. You would be hard pressed to understand any game without understanding the concept. But “eyes” don’t exist in the rules. It is, instead, an emergent property.

Similarly, “climate sensitivity” doesn’t exist in the coupled atmosphere-ocean GCMs that everyone thinks of as “the IPCC models”. It is a useful concept, it can be derived from model output, but its not part of the models2. Nor, indeed, is the balance between incident and outgoing radiation3. There is nothing like DE’s “G” in the AOGCMs. Things like climate sensitivity do exist in the highly simplified models that are tuned to the GCM outputs and used to run some sensitivity tests – but these aren’t the things that people think about when they talk about “the conventional basic climate model”.

So, at base, DE’s error is just to confuse two very different types of model. Note, however, that you can’t solve his problem by saying “oh yes well of course – I actually meant the simplified models” – because those aren’t the ones that people rely on to turn the physics into scenarios of how climate changes if you change CO2; they aren’t the ones that you poke if you want to understand how the GHE works. That’s done with the complex models.

[Update: post 9 of DE’s series makes the error again. It quotes Hansen: The patterns of temperature change are remarkably similar in the [total solar irradiance] and C02 experiments… This similarity suggests that, to first order, the climate effect due to several forcings including various tropospheric trace gases may be a simple function of the total forcing. And then parses that as this is Hansen saying that experiments based on his computer models show extra sunlight and extra CO2 have the same effect – which is nearly right; its not “the same” its “to first order”, but that’s not the important problem, the problem is the continued parsing His models are based on the basic climate model, which treats all forcings the same. No! the model doesn’t treat all forcings the same. They have it backwards. What the sophisticated models show is that the result of different forcings is often similar; but (again) that isn’t built into the models; it isn’t an assumption; its a result.

Note that this, too, makes it impossible for them to claim that they’re not talking about the big GCMs. Equation (1) of that post – which isn’t in such GCMs – once again makes it clear that they don’t understand the difference.]

So what does happen in yer AOGCM when you “increase the CO2”? Obviously, a massively complicated chain of complicated things, but I’ll attempt a massive oversimplification below. Some of which I understand. For the sake of simplicity, let us say that we suddenly double the CO2. In which case, all the way through the atmosphere, the radiation calculations change. It is tempting to say “and so the previous equilibrium is disturbed” but even that isn’t true. The model isn’t in equilibrium, except in “dynamic equilibrium”. Apart from anything else, there’s always the day-night cycle going on; and if you got rid of that, the atmospheric flow isn’t in stable equilibrium, only in dynamic equilibrium. Cast all that aside for the moment. Suddenly, there is more CO2, which means that the atmosphere (a) absorbs more long wave radiation (differently, in the multiple bands of LW that it uses) and (b) emits (ditto) more LW radiation. Exactly how that works out – in terms of different layers warming or cooling – is not entirely obvious, as the many attempts to explain stratospheric cooling witness. This happens throughout the model layers, and across the globe, everywhere differently, in terms of latitude and longitude. This will over time affect whether clouds form, the overall circulation patterns, the temperature of the surface, and all kids of everything in a pattern that lots of people have spent lots of time and papers trying to reduce into a comprehensible form.

Via twitter, The atmospheric general circulation model ECHAM6 is, I think, quite good if you want a sense of the complexity of the atmospheric component of a GCM. There are lots of equations in there, if you like equations. Section 2.3 describes radiative transfer, if that’s the kind of thing you like. One component of that is the various LW bands, which I’ll reproduce below:


No, that doesn’t tell you anything useful, unless you already know what it is 🙂

So to return to the first sentence, no the models don’t assume that CO2 warms the sky. The models implement some basic radiation physics that says that changing the atmospheric composition affects how it absorbs and emits radiation at different frequencies; but after that its left up to the implementation of the physics to determine warming or cooling. And as we all know, the stratosphere cools under GW, so the first quoted sentence is wrong even on its own wrong terms. The third quoted sentence from DE is more in not-even-wrong territory, and is clearly just junk.


1. Yes, “F” does indeed stand for Fuckwit.
2. Actually, its not quite as simple as that. Climate sensitivity doesn’t exist as a variable or equation in the AOGCM models, but people do examine the models carefully for what the derived CS is. Quite how much the models are tuned to a desired or acceptable CS is a bit of an open question (insert appropriate link here; I’m pretty sure JA has ranted about this, but can’t find it right now). And if you do decide to change your model’s CS its not a simple matter of turning a knob; you end up fiddling with a bunch of stuff you decide you might have got wrong, and re-running it to see if that made a difference.
3 In the sense that there is no overall equation for this balance. Of course, it is a fundamental concept, and a model that doesn’t “balance” in equilibrium wouldn’t be much use. But that balance is made up of countless tiny little interactions.


* Others have noticed DE’s problems with partial derivatives.