Traduit par Etienne Pesnelle
Parfois sur RealClimate nous discutons d’importantes incertitudes scientifiques, et de temps en temps nous essayons de clarifier et de répondre à quelque point ou élément de contexte subtil, mais d’autres fois, nous nous amusons un peu à souligner quelques-unes des absurdités qui passent occasionnellement pour de la “science” sérieuse sur le Web et dans les média. Ces articles semblent scientifiques aux profanes (il y a des équations ! des références à des physiciens du XIXème siècle !) mais, tels des oeufs de coucou dans un nid, ils sont uniquement conçus pour sembler suffisamment authentiques pour tromper les spectateurs et évincer la vraie science. Pour quiconque s’y connaît, un coup d’oeil rapide est généralement suffisant pour voir que les concepts sont massacrés, que la logique est semée aux quatre vents, et que des conclusions complètement non justifiées sont établies – mais les trucages utilisés sont parfois un peu plus subtils.
Deux spécimens qui ont récemment attiré l’attention entrent parfaitement dans ce moule. L’un de Christopher Monckton (un vicomte, pas moins, avec manifestement trop de temps à sa disposition) qui s’amène avec un jeu complet de “calculs” complémentaires qu’il a effectué sur son propre modèle climatique “M”, et l’autre sur JunkScience.com (“What Watt is what”). JunkScience est une devanture de Steve Milloy, longtemps lobbyiste pour les industries pharmaceutique, pétrolière et du tabac, et qui a été une source fiable de spécimens de “science-coucou” pendant des années. Assez curieusement, les deux spécimens utilisent le même tour de passe-passe pour tromper les imprudents (coïncidence ?).
Mais pas de panique, RealClimate est là !
Les deux spécimens passent tous les deux beaucoup de temps à discuter de la sensibilité climatique, mais, comme ils ne le disent pas ouvertement, cela pourrait ne pas être évident en première lecture – cela sans doute parce si vous faites un coup de Google avec les mots-clés “sensibilité climatique”, vous obtenez de nombreuses discussions sensées du concept provenant de wikipédia, de nous-mêmes et d’universités d’importance nationale. Nous avons souvent utilisé ici des arguments convaincants sur le fait que la sensibilité du climat à l’équilibre est le plus probablement d’environ 0,75° +/- 0,25° C/(W/m²), ce qui correspond à un accroissement d’environ 3°C pour un doublement du CO2.
Ces deux spécimens prétendent plutôt montrer, en utilisant des arguments “de bon sens”, que la sensibilité climatique doit être faible (plutôt de l’ordre de 0,2 °C/W/m², soit moins de 1°C pour 2 fois plus de CO2). Nos articles précédents auraient dû suffire pour démontrer que cela ne peut pas être correct, mais cela vaut la peine de regarder comment ils arrivent, arithmétiquement parlant, à obtenir ces valeurs. Pour vous éviter d’avoir à vous échiner dessus, je vais vous donner la réponse tout de suite : la clé est dans l’unité dans laquelle est exprimée la sensibilité climatique : °C/(W/m²). Tout changement de température (en °C) divisé par un flux énergétique (en W/m²) aura la même unité et pourra ainsi être “comparé”. Mais à moins que vous ne sachiez comment est défini le forçage radiatif (car c’est assez précis), ces valeurs apparemment similaires pourront vous induire en erreur. Ce qui est, je présume, le but.
Le lecteur doit être conscient d’au moins deux choses fondamentales. Premièrement, un “corps noir” idéal, dont la radiation est une fonction très uniforme et très prédictible de la température décrite par l’équation de Stefan-Boltzmann, a une sensibilité fondamentale (à la température de radiation terrestre) d’environ 0,27 °C/(W/m²). Ainsi, un changement d’environ 4 W/m² du forçage radiatif donne un réchauffement d’environ 1°C. La seconde chose à savoir est que la Terre n’est pas un corps noir ! Sur notre planète réelle, il y a de multiples rétroactions qui affectent d’autres composantes de l’effet de serre (albédo de la glace, vapeur d’eau, nuages, etc) et donc la vraie question à propos de la sensibilité climatique est de savoir à combien ces rétroactions s’élèvent.
Donc, le premier tour de passe-passe est ici. Ignorez toutes ces rétroactions, et vous obtiendrez évidemment un nombre qui est proche de celui qu’on obtient par l’approche du “corps noir”. Sans blague ! Toute approche qui met la vapeur d’eau et le CO2 dans le même panier revient en effet à cela (et si quiconque émet le moindre doute sur le fait que la vapeur d’eau soit un forçage ou une rétroaction, je lui demanderai de se référer à cet ancien article).
Comme nous l’expliquons dans notre glossaire, les climatologistes utilisent les concepts de forçage radiatif et de sensibilité climatique car ils fournissent un outil prédictif très robuste pour comprendre ce que seront les résultats d’un modèle pour un changement de forçage donné. La sensibilité climatique est un produit de sortie des modèles complexes (elle ne se décide pas à l’avance) et elle n’est pas très instructive sur les détails du résultat (par exemple les tendances régionales ou les changements de la variance), mais elle reste quand même pratique pour en brosser les grandes lignes. Empiriquement, nous savons que pour un modèle donné, une fois que vous connaissez sa sensibilité climatique vous pouvez facilement prédire de combien cela se réchauffera ou se refroidira si vous modifiez l’un des forçages (comme le CO2 ou le rayonnement solaire). Nous savons aussi que la meilleure définition du forçage est un changement du flux à la tropopause, et que le diagnostic le plus prévisible est une anomalie à l’échelle du globe de la température moyenne de surface. Ainsi, il est naturel de regarder dans le monde réel et de chercher des preuves qu’il se comporte bien de la même façon (et il semble se comporter ainsi, puisque les simulations rétrospectives du modèle fondées sur les changements passés correspondent très bien aux observations).
Pour notre tour de passe-passe suivant, essayez de diviser des flux d’énergie à la surface terrestre par des changements de température de surface. De façon évidente, cela n’est pas équivalent à la définition de la sensibilité climatique – c’est en fait équivalent à la sensibilité du corps noir (sans rétroactions) évoqué plus haut – et donc, encore une fois ce n’est pas surprenant que les nombres obtenus soient si similaires à ceux du cas du corps noir.
Mais nous n’avons toujours pas fini ! La prochaine chose à oublier de façon opportune est que la sensibilité climatique est un concept valable à l’équilibre. Elle vous donne la température que vous obtiendrez finalement. Dans des situations transitoires (comme en ce moment), il y a un retard lié au lent réchauffement des océans, ce qui implique que la température met un certain nombre de décennies pour rattraper son retard vis-à-vis des forçages. Ce décalage est associé au déséquilibre énergétique planétaire et à l’augmentation de la contenance thermique océanique. Si vous ne prenez pas cela en compte, la “sensibilité” observée sera toujours inférieure à ce qu’elle devrait être. En conséquence, si vous prenez le réchauffement observé (+0,6° C) et que vous le divisez par les forçages totaux estimés (~1,6 +/- 1 W/m²), vous obtiendrez un nombre grossièrement moitié moindre que celui attendu. Vous pouvez même allez plus loin – si vous ignorez le fait qu’il y a également des forçages négatifs dans le système (surtout les aérosols et les évolutions de l’utilisation des sols), le forçage issu de tous les effets réchauffants est encore plus important (~2,6 W/m²), et donc la sensibilité qui en découle est encore plus faible ! Bien entendu, vous pourriez prendre en compte le déséquilibre (~0,33 +/- 0,23 W/m² selon un document récent
Et finalement, vous pouvez complètement contredire tout votre travail précédent en laissant entendre que tout le réchauffement est dû au forçage solaire. Pourquoi est-ce contradictoire ? Parce que tous les tours de passe-passe ci-dessus marchent aussi bien pour les forçages solaires que pour les forçages des gaz à effet de serre (GES). Soit ce sont des rétroactions importantes, soit pas. Vous ne pouvez pas en avoir pour le solaire et pas pour les gaz à effet de serre. Nos meilleures estimations concernant le solaire sont qu’il représente environ 10 à 15% de l’ordre de grandeur du forçage des gaz à effet de serre pendant le XXième siècle. Même si c’est faux d’un facteur 2 (ce qui est concevable), c’est toujours moins de la moitié des changements dûs aux GES. Et bien sûr, quand vous regardez les 50 dernières années, il n’y a pas du tout de tendances dans le forçage solaire. Peut-être vaut-il mieux ne pas le mentionner.
Thanks. I’ve been looking for a good debunking of this article. I knew the numbers were wrong but my climate science knowledge wasn’t up to proving it. I have got used to the usual bunkum (like urban heat islands, water vapour, medieval warm period etc.) but quoting Stefan-Boltzmann equations was new to me.
Worth noting that Viscount Monckton lost a fortune (and his house) offering a million pound prize to solve a puzzle he’d set….it was solved fairly quickly. A case of ego and intellect out of equilibrium!
What follows is intended ad rem as the issue is as much semiotics as science.Viscount Monckton can rival Smullin when it comes to designing puzzles- he has published some that offer large rewards to the first brilliant enough to solve them. As a general rule the winners are not the editors of The Daily Telegraph.
I suspect you are right as to the appearance of dimensional analysis giving rise to seemingly plausible confusion, but nowadays one expects to find a bad lawyer behind an attempt to merchandise a worse hypothesis . Is there yet a compendium naming the top ten rhetorical ruses trial lawyers use and their more famous applications to scientific advocacy ?
Isn’t this the standard way to put across the agenda for global doom?
Gavin,
Your statement that “Thus it is natural to look at the real world and see whether there is evidence that it behaves in the same way (and it appears to, since model hindcasts of past changes match observations very well)” seems to indicate that you think there will be no changes in ocean circulation or land use trends, nor any subsequent changes in cloud responses thereto or other atmospheric circulation.
Just because models have been tuned to hindcast, can we assume they can forecast as well? Would you post a link to these model runs matching hindcasts?
Also, you say that land use changes (decreasing flora) are a negative feedback. When the sun is overhead, is not the Sahara hotter than the jungle? It seems to me it would be the other way around.
I noticed that most of the arguments in Monckton’s piece are the same-old-same-old faulty reasons. But one of them puzzled me. On page 15 he displays a graph of temperature for the last 1000 years based on borehole temperature reconstructions (from Huang). I know that his graph is erroneous, because the error envelope shrinks to size zero in the year 1600! Borehole temperature reconstructions necessarily exhibit dramatically increasing error ranges the further back in time one goes, so this cannot possibly be right.
However, I tracked down the Huang paper (1997, GRL 24, 1947), but only got the abstract, and it does seem to indicate that they conclude that temperatures were higher in the not-too-distant past than at present. I can’t find anything by Huang since then that addresses borehole reconstructions beyond the last 500 years or so. Any comment?
[Response: That is a curiousity that I have noticed as well. Most of the recent complations of borehole temepratures don’t go back more than 500 years – presumably because of data quality and signal-vs-noise issues (but maybe someone could enlighten me?), and the fact that no-one has followed up on Huang et al (1997) in almost a decade might imply that those are significant issues. That isn’t to say that improvements aren’t possible now…. – gavin]
Steve,
I would agree that unforeseen changes in ocean circulation could throw off model predictions, there are surely other wildcards too, but uncertainty like that is not your friend if you want to argue against avoiding climate change. As for models predicting land use changes, this is in the realm of human choice, so hardly a modeling issue.
See the TAR for hindcasting comparisons:
http://www.grida.no/climate/ipcc_tar/wg1/fig12-7.htm
Regardless of how hot the Sahara may feel when you stand in it, the difference in radiative effect between it and rainforest is in its higher albedo, reflecting more direct sunlight, the darker forests absorb more heat.
Looking at Dr Huang’s later work on temperature reconstructions from borehole data indicates that (as Gavin says) he hasn’t followed up the 1997 study, but instead has focussed on more accessible reconstructions from the last 5 centuries. These (judging by a perusal of his abstracts reproduced below) seem to accord more or less with the temperature reconstructions from other studies (including other borehole data).
So perhaps the earlier reconstructions are flawed. After all Huangs statement from his 1997 GRL paper that ” Temperatures were also warmer than present 500-1,000 years ago, but then cooled to a minimum some 0.2-0.7 K below present about 200 years ago.” seems to be incompatible with the statement from his Annual review paper from 2000 (see abstract below) that: “The average surface temperature of the continents has increased by about 1.0 K over the past 5 centuries; half of this increase has occurred in the twentieth century alone.”
—-abstracts:
Title: Climate change record in subsurface temperatures: A global perspective
Author(s): Pollack HN, Huang SP, Shen PY
Source: SCIENCE 282 (5387): 279-281 OCT 9 1998
Abstract: Analyses of underground temperature measurements from 358 boreholes in eastern North America, central Europe, southern Africa, and Australia indicate that, in the 20th century, the average surface temperature of Earth has increased by about 0.5 degrees C and that the 20th century has been the warmest of the past five centuries. The subsurface temperatures also indicate that Earth’s mean surface temperature has increased by about 1.0 degrees C over the past five centuries. The geothermal data offer an independent confirmation of the unusual character of 20th-century climate that has emerged from recent multiproxy studies.
Title: Climate reconstruction from subsurface temperatures
Author(s): Pollack HN, Huang SP
Source: ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES 28: 339-365 2000
Abstract: Temperature changes at the Earth’s surface propagate downward into the subsurface and impart a thermal signature to the rocks. This signature can be measured in boreholes and then analyzed to reconstruct the surface temperature history over the past several centuries. The ability to resolve surface temperature history from subsurface temperatures diminishes with time. Microclimatic effects associated with the topography and vegetation patterns at the site of a borehole, along with local anthropogenic perturbations associated with land use change, can obscure the regional climate change signal. Regional and global ensembles of boreholes reveal the broader patterns of temperature changes at the Earth’s surface. The average surface temperature of the continents has increased by about 1.0 K over the past 5 centuries; half of this increase has occurred in the twentieth century alone.
Title: Merging information from different resources for new insights into climate change in the past and future
Author(s): Huang SP
Source: GEOPHYSICAL RESEARCH LETTERS 31 (13): Art. No. L13205 JUL 8 2004
Abstract: An understanding of climate history prior to industrialization is crucial to understanding the nature of the 20th century warming and to predicting the climate change in the near future. This study integrates the complementary information preserved in the global database of borehole temperatures [Huang et al., 2000], the 20th century meteorological record [ Jones et al., 1999], and an annually resolved multi proxy model [ Mann et al., 1999] for a more complete picture of the Northern Hemisphere temperature change over the past five centuries. The integrated reconstruction shows that the 20th century warming is a continuation to a long-term warming started before the onset of industrialization. However, the warming appears to have been accelerated towards the present day. Analysis of the reconstructed temperature and radiative forcing series [Crowley, 2000] offers an independent estimate of the transient climate-forcing response rate of 0.4-0.7 K per Wm(-2) and predicts a temperature increase of 1.0-1.7 K in 50 years.
I have a somewhat off-topic question / request for comment. I came up with it while thinking up ways to try to explain to lay persons the effect CO2 has on temperatures.
In short: You are on a particular place on Earth and the sun has just set. Let’s imagine that in an instant, the CO2 concentration in the entire atmosphere doubles. What difference would this make by morning? (Let’s say for the sake of argument that winds overnight will be very light, the skies are clear and other sources for “noise” during the relevant period are low)
Based on my understanding, it would be correct to say that the effect of doubling CO2 while there is no sunlight is for the temperature drop during the night to be slower – meaning, the minimum and average temperature will be higher than it would have been otherwise. (A bit like adding double-glazing to your house). In addition, this temperature difference would be measurable and dependable. (Side-note: I’m not attempting to put a number on this)
The secondry idea behind this thought experiment is help explain the difference a rise in CO2 causes compared to an increase in output from the sun – both increase average temperatures (during the day and the night) but there are differences. And the differences can be detected and measured.
From a scientific perspective, looking at the temperature for just one night is probably not very useful. However, I think the explanation above would be more easily absorbed by the lay person.
Maybe there’s a better way to help explain the effects of CO2 to the lay person though – particularly how it compares with solar forcings. Any thoughts?
Re #6,
Coby, you misunderstand me still. I am not arguing against avoiding climate change. I am arguing that we don’t know enough one way or the other yet, since CO2 is the base of the food chain and there are a lot of other forcings out there. If I were to frame it from your statement, I would have to say that *all* uncertainty is my friend – not that I personally would consider that to be the case.
As far as the TAR, the graphs you point to are not impressive. Further, they don’t impress the TAR scientists either, who write “the instrumental record is only marginally useful for validating model estimates of variability on the multi-decadal time-scales that are relevant for detection”
http://www.grida.no/climate/ipcc_tar/wg1/466.htm
Regarding your statement on albedo, perhaps Chapter 12 would clear that up for you. Also, there is the question (unresolved to my knowledge) of how much of that reduced albedo goes into biochemical reactions rather than sensible heat.
Differentiating SB eqn. and solving for dT/dQ, then solving for T=288 K (average surface temperature), I get dT/dQ=0.18W/m2. If I use T=255K, I get the 0.27W/m2. Also, literature I have seen gives an average surface emissivity for earth of close to 1.0 for the far IR, so a blackbody is probably a reasonable assumption, no? So for 3.7W/m2 additional forcing from C=2*C0 (calculated from IPCC formula), I get only about 0.67K for change in T, neglecting feedback and emissivity. Most sources I have seen (other than junkscience) report about 1-1.2K. Is the difference emissivity? Or maybe how I am interpreting the definition of radiative forcing?
[Response: If the Earth was a blackbody, the surface temperature would be 255K (so therefore it can’t be). Greybody is slightly better, but it still isn’t correct. You really need to account for the vertical structure of temperature (the lapse rate ), and if you want your model to get a number of basic things right you need to include spectrally grey absorbers – plus the additional mixing in the troposphere (which depends on convection, and hence affects water vapour feedbacks) etc…. The basic answer is that there isn’t an extremely simple model for how it works. Radiative-convective models are pretty good (but they still need a lot of assumption built in) and so we end up needing GCMs pretty quickly. The ~1 deg no-feedback case comes from radiative-convective models that are a little more sophisticated than just SB – (but 0.27*3.7 = 1 C anyway). But everything is in the feedbacks. – gavin]
Steve says:
“Also, you say that land use changes (decreasing flora) are a negative feedback. When the sun is overhead, is not the Sahara hotter than the jungle? It seems to me it would be the other way around. ”
And when the sun goes down, what happens then?
At the risk of talking out of my ass, I think the main effect of razing tropical rainforest is to decrease transpiration, which decreases relative humidity, which decreases overnight temperatures. Think of it was a negative water vapour feedback.
Re #5 and 7, I think I have traced through the issue of Huang and Monckton. As usual Michael Mann is in the middle of it.
The short is that the funny graph is a blow up of a long term borehole reconstruction which has “”some problems””. The three lines are not the average and two error limits, but the results of using three different priors. Moreover that reconstruction is incompatible with Huang and Pollack’s 500 year reconstructions (and the various MBH etc hockey sticks including Esper.
Re #11,
“And when the sun goes down, what happens then?”
Good point. What is the average summer temperature of the Sahara etc.? I can’t seem to find it. I find dozens of “trends” and “anomalies” but no actual temperatures…
>a compendium naming the top ten rhetorical ruses trial
>lawyers use and their more famous applications to scientific advocacy ?
Volokh?
re 14
Where has Volokh ( For Gavin’s benefit, V is a politically savvy policy blogger) elaborated on this?
The first thing that comes to mind is the Phillips gambit- the post hoc assertion that dimensional analysis notwithstanding, legaland scientific evidence are interchangeable . Therefore , if truncating or throwing out scientific evidence ( limine is the legal term of trial lawyerly art) leads to a jury concluding that , say, evolution isn’t so, all good men and true must concede that the Discovery Institute has won and Darwin has lost the case.
It is tactically shrewd , insofar that nterposing just one said-to-be ‘expert’ with contrarian views in any science case can prevent ajury from reaching consensus , because absent expertise of their own, they tend to equate the existence of ‘expert’ dissent, however dubious , with reasonable doubt
Google: night temperature Sahara
March:
Daytime temperature about 25/35°C (77/95°F), night temperature about 8/15°C (46/59°F).
http://www.terramia.com/sahara/
Speaking of Cuckoo Science, Piers Corbyn (of Weatheraction and “I won’t take James Annan’s bet” fame) got a letter into the Guardian today that appears, to this dilletante, to be a prime example of the genre.
The main claims of fact he makes in support of his contention that Global Warming science is an ‘idealogy, underpinned by false assumptions’ are:
o Ice core and sea-bed sediment measurements show no evidence that changes in CO2 drive world temperatures or climate.
o 8000 of the 10000 years since the last ice age were warmer than now and generally had less CO2 and lower sea levels
o For 3000 years (from 5000 BP to 2000 BP) world temperatures were falling whilst CO2 levels were rising
o Manâ??s CO2 is only worth 1% of the total greenhouse effect
o Human CO2 and itâ??s effects are absorbed or negated by feedback mechanisms of plants and sea
Does anyone here care to take a crack at these?
Regards
Luke
Monckton is everywhere on the blogs and I had planned to catch up on him.
I found his notes (he calls them a paper) very odd and a bit baffling. Your article above makes a good start but the first part of it , which I managed to work out from Monkton is really only about terminology. Without going back to check, it appears to me that the the substantive discussion only begins when Monckton tries to justify that the black body sensitivity is roughly the same as the observed sensitivity which, if it were true,would imply that the sum of the feedbacks must be small.
Your answer so far is that his estimate of the observed sensitivity ignores time delays. Have I got that right ? Is that the whole story or could there be any other contributions?
I noted that his covering article started very politely (“gentle reader”) but soon led to some extremely aggressive implications for example:
1. He argues that the solar and anthropogenic forcing have not been treated equally i.e that only the latter has been boosted by feedback in the TAR. This appears to me extremely unlikely but since I have neither written nor read a climate model code I cannot go around making that assertion. Of course there are other arguments against the simple solar hypothesis (e.g stratospheric cooling which has been covered in RC).
2. That the climate models (which he labels as UN) must have double counted the feedbacks. Sounds like libel to me but I’d like to hear your views.
Incidentally I spent some time last year trying to expose this sort of thing (including the more naive versions) and wrote it up in a few essays at :
http://www.trumpington.co.uk/green
It will need up-dating (possibly correcting?).
Re: #12
Thanks!
Re #16, that doesn’t get anything worthwhile. March is not summer for one thing.
Secondly – on further thought, we’re talking about insolation which is daytime anyway. I did find that the world’s highest temperature was 136 deg F and was in the Sahara…
Google, Steve. Decide on your question, use the search. Lots of info available.
http://www.bbc.co.uk/weather/world/city_guides/results.shtml?tt=TT000170
Whilst I’m delighted to read a scientific rebuttal of the Monckton and Milloy articles, I’m dismayed by the personal attacks and tone it has taken. It is perfectly reasonable, not to say absolutely necessary, to say chapter and verse how and why they are wrong. However, it is of no use at all to have this arsenal of information undermined by cheap shots. Let the science do the talking?
Also many thanks, Geoff for the URL for trumpington. Very helpful.
>14, 15, Russell — I meant “volokh” as the weblog, not the person sponsoring it; look back at the Judith Curry hurricane thread for a visit here by a lawyer who’s active at volokhconspiracy, that will show in the search — he’s the gentleman who was arguing that an increase in force 4 hurricanes (based on statistics, there are lots of 4s) can’t possibly be the basis for expecting an increase in force 5 hurricanes (there are so few 5s that the statistics don’t suffice, if you consider them separately). Lawyerly argument was, a 4 is completely different than a 5, you can’t say 5s increase with warming just because 4s do. To the hurricane scientists, big heat engines and slightly bigger heat engines are both going to change the same way when heat increases. I asked in the thread if he thought expectations about increases in forest fire size would be comparable; don’t think the gentleman has been back to comment further.
Search here isn’t working for me right now, FF 2.0/OSX bug, or I’d find it for you.
Tell you what Steve, show me that you’ve donated $100 US to Greenpeace (send the receipt to my Email) and I’ll tell you how to find that data. If you want to play a long game of why, I know several charming three year olds who will entertain you for hours.
Gavin, I’m disappointed that Roger Pielke, Sr. has not commented on the points you raise here, given that his calculations are used in the Junkscience article
[Response: ‘ab’-used would be closer to the truth. But RP Sr. makes his own choices about what to comment on…. – gavin]
>14, 15, 23 re sources of
“rhetorical ruses trial lawyers use and their more famous applications to scientific advocacy”
Here’s another resource:
/co2science.org/scripts/CO2ScienceB2C/subject/h/hurratlangwe.jsp
“… It is a typical (but very thorough) example of what advocacy groups on both sides do: they behave like lawyers who are paid to start with either the innocence or guilt of their client, then proceed to present evidence that supports the verdict they have already decided they want….”
— Dr. Judith Curry, in a comment made 11 September 2006 @ 7:11 pm at /climateaudit.org/?p=803#comment-45463
With reference to comment no.18. (2nd. paragraph).
I’m sorry for being in a hurry before. I missed the remark in the main essay about Monckton having neglected the aerosols in his estimate of the forcing. Quite a serious point. Instead of an error, this is beginning to look like a “conspiracy of errors”.
When you experts get some spare time it might be worth your while submitting a letter to the Sunday Telegraph. It might be accepted. This is of some importance because of the supposed status of the paper. There are many influential people in the UK who regard it as a reliable paper (you only have to listen to the presenters on the BBC who refer to what they have “seen in the Telegraph”).
Monckton’s article (he is a journalist after all) covered a broad spectrum of issues which collectively have been pushing the AGW argument one way. By addressing these issues he is simply attempting to push it back the other way.
In short, as a ‘reader’, I find the article to be concise, clear and supported with lots of analysis and data. What I, as reader want to see is a simple annotation of this original article with your explanatory facts as to why you disagree – in the same ‘language’, at the same journalistic level. Too much to ask? If this request leaves you feeling ‘defensive’ you need to ask yourself why? After all – all us lay-people are asking for is a clear representation not of the facts, but of the arguments.
[Response: The issue is not that we are defensive – we have covered these issues over and again – but these points are not new. They are used all over the place. As working scientists, we don’t actually have time to annotate every single piece that comes out that rehashes these same talking points. Thus we generally only address points that we feel haven’t been covered before and that actually have some interest. Pick any of the substantive points and I’ll point you to a good rebuttal (check the index, or the guide on ‘A few things ill-considered’ (see sidebar)). Be careful not to be persuaded on its scientific merits by it’s length or seeming erudition – as in the examples I use above, it’s very easy to give a superficial psuedo-scientific description of something without it making any actual sense. – gavin]
Perhaps Coby could be persuaded to assign a unique number to each of the ill-considered arguments.
Then readers could Bingo on the arguments simply and easily — and anyone could submit to RC a copy of the article with the Bingo numbers inserted next to each ill-considered argument.
They do repeat themselves, don’t they?
When doing any writing or comment, one request again:
–>add paragraph breaks between major ideas in your responses.
Oh, please.
Re #28…You perhaps don’t have the particular knowledge of this subject (one doesn’t have to be an expert ‘though!) to see that Mr. Monckton’s Telegraph piece is a disgraceful (and presumably wilfully so) misrepresentation of the science on this subject. Unfortunately that’s the point and the problem – Monckton knows that he can effectively tell untruths since he is relying on a lack of knowledge on the part of the general reader. And sadly he’s allowed to do this in a National newspaper. The latter seems part of the unfortunate modern editorial practice in the media (TV and print) in which every subject of real or potential sociopolitical interest has to be given a veneer of “balance”. But in what manner does an article constructed of “untruths” provide a balance to the “truth”?
I have no connection with climate science. But even so I can identify the myriad misrepresntations in Monckton’s piece that are objectively wrong as matters of fact, not opinion. Thus leaving aside the points highlighted in the introductory article by Gavin “Cuckoo Science” the following are easily identified “howlers”
1. Monckton makes the standard attack on the Mann “hockey stick” temeperature reconstruction and then asserts that the Medieval Warm Period (MWP) was “up to 3 oC warmer than now”. However the temperature reconstructions in the proper scientific literature show that the MWP was significantly cooler that now. So even in a paper entitlied “Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data” [Moberg A et al. 2005, Nature 433, 613-617â??], the MWP is around 0.6-0.7 oC cooler than now. The same conclusion applies to the data of Osborn and Briffa (Science 311, 841, 2006), Bradley et al (Science 302, 404, 2003), Mann and Jones (Geophys. Res. Lett. 30, CLM 5-1 (2003), Crowley (Science 289, 270, 2000) etc. etc.
Now if one is going to use past temperature reconstructions to make a point to the reader in a newspaper, what is the point of not representing what the science says on this issue? This isn’t a matter of opinion, or of “balancing the argument”. It’s a question of telling the truth or not about the science. If Monckton wishes to write an op-ed piece then he should be honest with his readers and say that his piece isn’t actually based on science.
2. Monckton says “The Antarctic, which holds 90 percent of the world’s ice and nearly all its 160,000 glaciers, has cooled and gained ice-mass over the past 30 years, reversing a 6,000-year melting trend.”
This is (a) untrue and (b) a misrepresentation of the real issue.
a) The Antarctic isn’t gaining mass. Some parts are but overall the evidence indicates that it’s losing mass. A pair of satellites (GRACE) were launched several years ago to determine mass balance in the Antarctic and Greenland ice sheets. These (and other studies) indicate that Antarctica is losing mass. The relevant papers are [Velicogna and Wahr 2006 Measurements of time-variable gravity show mass loss in Antarctica Science 311, 1754-1756 and Rignot and Thomas “Mass balance of polar ice sheets” Science 297, 1502-1506]
b)b) notice that Monckton rather hides away from addressing the real issues. First, the loss of mass in the Antarctic ice sheet is actually somewhat unexpected. In no models or predictions of future warming scenarios does the Antarctic ice mass melt to any significant extent. The reason is that if an ice sheet is at a temperature of say ~20 oC where it never undergoes a seasonal melt, then even a very large temperature increase (say 10 oC) isn’t going to make it melt either! Secondly, and more importantly the concern is the Greenland ice sheet which Monckton conveniently chooses not to mention. This is the real concern. This ice sheet is losing mass at a rather larger rate (around 220 cubic kilometres per year) and it will take only another 1-2 oC world warming to raise the summer melt zone to the top of the Greenland ice pack after which point, in my understanding, the ice sheet will go into irreversible melt.
3. Monckton says: “First the UN implies that carbon dioxide ended the last four ice ages” [This is actually untrue the “UN” implies no such thing, nor does any competent scientist!] “It displays two 450,000-year graphs: a sawtooth curve of temperature and a sawtooth of airborne CO2 that’s scaled to look similar. Usually, similar curves are superimposed for comparison The UN didn’t do that. If it had, the truth would have shown: the changes in temperature preceded the changes on CO2 levels.”
Monckton must know full well that his discussion on this point is ludicrous. No one says that there is anything mysterious about the relationship between raised CO2 levels and warming/cooling during glacial/interglacial cycles. These cycles are caused by variations in the Earths orbital properties around the sun. Clearly any changes in CO2 levels HAD TO follow changes in temperature, at least initially, and this is obvious, well understood in general terms and no one is trying to hide the fact, for goodness sake, as Monckton implies. Equally obvious is the fact that raising CO2 levels (as we are doing) will raise temperatures independently of any changes in the Earths orbit/suns effects.
So it’s very obvious again that Monckton is cheating his readers here by making what must surely be wilfully misrepresentational descriptions of the issue. He’s playing the tired game of pretending that because CO2 levels clearly followed temperature changes in glacial/interglacial transitions, at least initially, that ergo CO2 levels can ONLY follow temperature changes. He’s surely doing this deliberately.
4. Monckton says: “The number of temperature stations round the world peaked at 6000 in 1970. It’s fallen by two-thirds to 2000 now: a real ‘hockey stick’ curve, and an instance of the UN’s growing reliance on computer guesswork rather than facts”
Again, Monckton must surely know full well that for the last 25-30 years satellite temperature measurement of sea and land surface have replaced terrestrial temperature station measurements in many cases since these give a much greater coverage (70% of the surface of the Earth is water…it’s difficult to put weather stations on top of ice sheets etc.!), are accurate [I presume!] and don’t suffer from any urban heat contributions etc.. One can only guess why Monckton pretends that there is something wrong with contempory temperature measurements by pretending that the coverage has plummeted.
etc. etc. I actually came up with a list of about 12 of these. They are very easy to spot, but depressingly tedious to “refute” in a manner that doesn’t look like one is just countering one piece of propaganda with another. It takes a bit of time to hunt down the relevant papers that address the specific points.
And therein lies the problem. If a newspaper isn’t going to do a proper editorial job of assessing the accuracy of what goes into their paper, then the general reader is (as we say in the UK) stuffed!
Thanks for the BBC link Hank. Here’s one on the equator in the jungle for comparison:
http://www.bbc.co.uk/weather/world/city_guides/results.shtml?tt=TT000770
As you can see, with the sun overhead the desert is around 10 deg C warmer.
However, this doesn’t really mean a lot as not only is there biochemical production as an enthalpic reaction using up energy, but there is also latent heat of evaporation.
Eventually the latent heat will return to sensible heat when clouds are formed through convection. But, what do clouds do to albedo?
Also, increasing CO2 holds more heat to the surface. More heat near the ground will increase convection, since as we all know, hot air rises. How much has increasing CO2 increased convection in the last 100 years? I have only seen it treated as a constant. Maybe you can help me out there…
Steve, formulate your question, type it into the Google search box, or ask your reference librarian for help. I’m just reading this the same way you are and trying to give you examples of how to find this stuff yourself. Any good librarian, public or school, will be glad to help you.
>increasing CO2 holds more heat to the surface.
Where are you getting that? What’s your source, why do trust that source for what you believe?
> More heat near the ground will increase convection, since as we all know, hot air rises.
> How much has increasing CO2 increased convection in the last 100 years?
> I have only seen it treated as a constant. Maybe you can help me out there..
Sure can. There’s this empty rectangle near the top of your screen. It may have a big letter “G” in it, or the word “Google” in or near it. Copy your questions off the screen and paste them into that box.
You’ll find a long, quite recent, prior discussion, with reference, on exactly the same questions you’re repeating here.
Funny how that happens.
Lot of latent heat of evaporation in the Sahara. More in the Pacific. You had a point Steve?
Sure did Eli – I was wondering what the magnitude of the negative feedback due to increased convection was, especially considering that increasing convection increases cloudiness. Can we reasonably quantify that?
Final note to Hank – yes, increasing CO2 increases the lapse rate, which holds more heat closer to the surface. Try Google.
Re: #30.
Chris.
Thanks Chris you have been doing some useful hunting. There are two kinds of global warming theory contrarians i.e. skeptics and misinformers. I’m wondering how you might classify the material mentioned in comment #17?
(Luke is referring to The Guardian Letters page on at Friday Nov.10th. )
The author is a private meteorologist and the letter includes a subtle form of advertising . I have no objection to that , except that he seems to suggest to the reader that a one year forecast does not need CO2, and that by implication a long range forecast might also be better without bothering with CO2. He asserts that “mankind’s CO2 is of no consequence in climate change”.
As far as I can see his alternative is the solar/magnetic/cosmic ray/cloud /hypothesis (hard to test but a genuine skeptical alternative?) together with some of the old recycled stuff . I should imagine that his model is not in the public domain. Is this just a question of betting?
Just in case you were wondering why ‘The Sunday Telegraph’ has devoted two whole pages over the last couple of weeks to Monckton’s amateur re-interpretation of the data, rather than inviting somebody with a track record in climate research to write about the issue, I think I might be able to shed some light on the issue.
Christopher Monckton’s sister, Rosie, is married to Dominic Lawson, former editor of ‘The Sunday Telegraph’. Lawson himself had a crack at climate researchers a couple of months ago in ‘The Independent’ newspaper describing them as alarmists. Monckton’s father-in-law is Lord Lawson of Blaby (Nigel Lawson, former UK Chancellor of the Exchequer), who has contributed many times to the public debate on climate change, most recently in a speech to the Centre for Policy Studies, in which he drew parallels between climate researchers and Islamic fundamentalists.
The director of the Centre for Policy Studies is Ruth Lea, who has a weekly column in ‘The Daily Telegraph’ (the sister paper of ‘The Sunday Telegraph’), which she has used no fewer than nine times in the last six months to present her own novel views on climate research and accuse climate researchers of all sorts of misdemeanours, including Lysenkoism.
I think there might be some sort of connection here. I guess the proof will be if Nigella Lawson, celebrity supercook and sister-in-law to Monckton, is given space in a future edition of ‘The Sunday Telegraph’ to explain how her analysis too shows that climate researchers have got it wrong.
Steve, I can’t figure out what’s new in your question. It’s a difficult area. Did you read the prior discussion?: https://www.realclimate.org/index.php?p=58
That’s been revisited several times and isn’t done yet, and a good example of how hard it is to deal with this. The geocities link might be where you’re getting your questions?
Steve, I’d assumed you were reading here last August but don’t see any questions in the thread here from you — but the answers to your questions are here. Why not refer specifically to what’s already posted? It might make clear what it is that you don’t understand.
https://www.realclimate.org/index.php/archives/2006/08/climate-feedbacks/
Re 31
As was repeatedly pointed out in the long conversation in How Not to Attribute Climate Change, starting at comment 126, convection is not a constant in GCMs. Googling gcm convective feedback amply demonstrates that.
Re 35
In that same conversation you asserted, The observed lapse rate is the wet adiabat. Think about it. How could it be otherwise? That suggests negative feedback on the lapse rate (see NAS 2003). A smaller temperature gradient suggests weaker convection, though there’s a lot going on though so “all else equal” arguments don’t prove much. Still, the small scale of convection in the overall energy budget suggests that it’s a weak feedback (see comment 187 in How Not to Attribute Climate Change).
In any case it seems at best optimistic to pin hopes on negative convective cloud feedback, because getting clouds takes water vapor, and the water vapor feedback is unambiguously positive – unless you’re an adaptive iris adherent.
In other news…
http://www.copernicus.org/EGU/annales/24/7/2025.htm
“… being considered by the US Air Force and the US Defense Advanced Research Projects Agency,… using very low frequency radio waves to flush particles from [the Van Allen radiation] belts and dump them into the upper atmosphere over either one or several days.
…
“…. The disruptions result from a deluge of dumped charged particles temporarily changing the ionosphere from a ‘mirror’ that bounces high frequency radio waves around the planet to a ‘sponge’ that soaks them up,” Dr Rodger says.
“The researchers also calculated the likely effect of remediation on the ozone layer, but found that ozone depletion would be short-lived and similar to that resulting from natural processes such as large solar storms and volcanic eruptions.”
The original paper is available online at
http://www.copernicus.org/EGU/annales/24/7/2025.htm
Rodger, C. J. , Clilverd, M. A., Ulich, Th., Verronen, P. T., Turunen, E., and Thomson, N. R., The atmospheric implications of radiation belt remediation, Annales Geophysicae, Page(s) 2025-2041, 2006.
——–
Hey, what could go wrong, eh?
Tom –
Along the lines of what I was thinking. However, you have not actually quantified convection. Trenberth et al say it’s a constant, others totally disregard it:
http://oceanworld.tamu.edu/resources/oceanography-book/radiationbalance.htm
I take it then you disagree with that.
Also, you have to remember that a part of convective feedback is cloudiness. If there is an equivalent to the iris effect, I would think it would be changing albedo.
But you have not answered the question. I’ll make it easier to start. When was convection 24 w/m^2 as Kiehl and Trenberth say, and what was it including cloud feedbacks?
Thanks,
http://www.google.com/search?q=convection+24+w%2Fm%5E2+Kiehl+Trenberth
Results … about 138 for convection 24 w/m^2 Kiehl Trenberth.
Re ” I should imagine that his model is not in the public domain.”
If it isn’t, then it’s not science he’s doing, but something else. Modern science depends on peer review and science in general has always required the ability of other scientists to duplicate your results.
Steve, search Google on your own name +cloud +feedback +uncertainty. You’ve been making the point that there’s cloud feedback uncertainty at least since http://www.john-daly.com/TAR2000/tar2000.htm
I find no one disagreeing with you. Yes, there’s uncertainty, and maybe more uncertainty now than then, considering positive cloud feedbacks. http://atoc.colorado.edu/~seand/headinacloud/?p=21
Is there something more than this? Something you believe that you want to lead others to by a Socratic dialogue?
2006’s “Upper Class Twit of the Year” nominee Cristopher Monckton responds to the RC challenges in 1 paragraph in this ‘article’.
http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/11/12/nclim12.xml&page=2
His carefully considered response to the techinical issues raised here:
“I received emails saying I’d wrongly assumed the Earth was a “blackbody” with no greenhouse effect at all (I hadn’t). The https://www.realclimate.org website, run by two of the “hockey-stick” graph’s authors, said the same in a blog entitled “Cuckoo science”.”
Analysis:
1) Unsubstantiated denial, “I hadn’t”.
2) An ad-hominen, “run by two of the “hockey-stick” graph’s authors”.
3) er,
4) that’s it.
An earlier post refers to the ‘Huang’ graph on page 15 of the Monkton paper.
I would be interested in your comments regarding the content of this February 2006 posting in physicsforums:
http://www.physicsforums.com/showthread.php?t=109844
A link is available from the poster to the Huang et al original 18000 yr graph, but he could find no link to the original paper submitted to Nature and declined, which included it. Including the Huang website.
He is able to provide a link however to their later, accepted paper, which includes the 500 year graph, but no reference to their earlier paper (or graph).
It is quite clear that the two graphs create opportunities for opposing conclusions, hence the concern of the poster (and Deming) that Nature might be selectively publishing papers which support a particular view.
Regards,
Seamus
I’m not an expert on this. My doctorate is in logic and philosophy, as you see from my website.
The Monckton article seemed perfectly reasonable to me, and the attacks on him here are mostly ad hominem. So what if he is a journalist, or a peer (though maybe not the peer-review sense)? It’s not enough to say it is ‘cuckoo science’. Why? Chris says ‘Monckton makes the standard attack on the Mann “hockey stick” temeperature reconstruction and then asserts that the Medieval Warm Period (MWP) was “up to 3 oC warmer than now”. However the temperature reconstructions in the proper scientific literature show that the MWP was significantly cooler that now.’ That begs the question. Monckton cites numerous papers that suggest ‘northern-hemisphere evidence’ for the mediaeval warm period, and cites a dozen studies from the southern hemisphere. He cites McIntyre et al. (2003, 2005) who apparently demonstrated that the erasure of the mediaeval warm period in the 2001 graph had been caused by inappropriate data selection and incorrect use of statistical methods (rReliance upon bristlecone pine data). He cites numerous experts as saying the Mann study was flawed.
I’m sure all these citations are flawed, but would someone like to say why? Stick to the ‘hockey stick’ one.
frege@btinternet.com
Edward
re: 48. It is quite simple to look at https://www.realclimate.org/index.php/archives/2004/12/index/ and then view the numerous listings/discussions under “Paleo-Climate”. The numerous “flaws” in McIntyre et al are specifically discussed.
As for Monckton’s credentials, they are as a journalist, period. Not as a scientist, let alone a peer-reviewed scientist. That a journalist with no climate science research background could attempt to seriously refute peer-reviewed research is simply ludicrous. It is certainly not within the realm of following the scientific method.
I’m sorry but I just don’t get the point of this article. I’ve read it a couple of times – and read some of the links it references – but it says nothing. Milloy and Monckton (whoever they are) have used the S-B formula to provide a decent “back of the envelope” estimate to the temperature increase in response to more CO2. We all know there might be uncertainties such as feebdback effects (positive or negative) which the article talks about but makes no attempt to quantify. And as for any justification why these effects produce 3 times more warming than the S-B calculation – forget it. It’s just a piece of sneering waffle that hides behind the complexities of General Circulation Models – or computer programs to the rest of us. Aren’t the GCMs developed by humans? How are their results validated? Tell us why the GCMs are right and Milloy and Monckton are wrong.
There might be something I’ve missed but the only piece of evidence seems to be the ‘forcings’ in the last ice age i.e. the ~7 w/m2 reduction mainly due to lower GHGs and more ice sheets. Water Vapour is not included because it’s a feedback apparently. But lower GHGs in the last ice age were also a feedback – weren’t they? Or are you actually saying that lower levels of GHGs brought on the last ice age? Tell us more – I’ve not heard this before.
To all this who have been complimentary to Gavin’s article: I challenge you to explain the huge discrepany between Milloy’s “back of the envelope” calculation and the results obtained by the GCMs.
Anyway I’m going to read up on all the referenced posts again, but it would be useful to have a bit more clarity.
[Response: This is a subject we’ve dealt with more carefully in the past and in order to not spend time repeating ourselves, we left the explanations as links. If you can’t find what you are looking for in here or here, let me know and I’ll try again. – gavin]