Comment (2-26):Comments?
A commenter (3722) suggests that average global temperature is not an adequate “starting point” as an indicator of climate change “[c]onsidering the multitude of physical processes that control climate.” The comment indicates that “global temperature systems are not homogeneous, and are indeed characterized by large differences and variability.” The comment refers to Essex et al. (2007), who conclude “Physical, mathematical, and observational grounds are employed to show that there is no physically meaningful global temperature for the Earth in the context of the issue of global warming to support this notion.”
Response (2-26):
We have reviewed the paper by Essex and considered the commenter’s view regarding the usefulness of global temperature as a “starting point” and we disagree that it is not a useful indicator. We note that the TSD does not rank the importance of any individual indicator or suggest that global average temperature is the most important indicator. Rather, it summarizes the scientific literature on a large set of indicators (including changes in sea level and ocean heat content, glaciers, snow cover, precipitation, and a large number of physical and biological systems).
With respect to the Essex et al. study, the authors claim that “physical, mathematical, and observational grounds are employed to show that there is no physically meaningful global temperature for the Earth in the context of the issue of global warming.” We do not dispute that a single global average temperature may not be particularly meaningful to understanding global warming and concur that global temperature systems are not homogeneous. But Essex et al. are neglecting the fact that climate scientists are not particularly interested in a single average value, but rather the change or variation in temperature expressed as anomalies over time at a range of spatial scales, from local to regional to global. Analysis of temperature anomalies is a legitimate, extensively peer-reviewed, expertly assessed methodology for understanding temperature trends at all scales.
Thus, the TSD appropriately summarizes the literature and that its discussion of global temperature is reasonable, informs our understanding of climate change, and is consistent with the scientific literature.
Saturday, April 03, 2010
Eli can retire Part IV - Essex, Beenstock, Reingewertz and VS take it on the chin
Continuing Rabett Run's excerpts from the US EPA responses to challenges to its Endangerment Finding for increasing CO2 concentrations, Eli has it in for Essex, Beenstock, Reingewertz (really go to Our Changing Climate for this) and VS, Bart's little Mrs. Calabash.
22 comments:
Dear Anonymous,
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The management.
It strikes Horatio that the EPA has some very smart people working for them who are able to cut right to the chase of each issue and, with just a few words, point out what is wrong with the arguments they are critiquing (including strawman arguments like those of Essex et al)
ReplyDeleteTo be able to critique/summarize this stuff so well and so succintly is actually a rare and welcome combination of talents.
I don't expect that the author team is exactly a secret. Does anyone know who they are?
ReplyDeleteSO, I hope a few people write to the EPA about this, if only to say:
ReplyDelete"Thanks for being competent."
What John Mashey wrote.
ReplyDeleteI agree, it was very concise and competent. Do you think the commenter understood it?
ReplyDeleteOn this "Bunny Eve", it is appropriate to think the rabbit here for finding these.
I think that the deniers might have missed a paper:
ReplyDeleteBeanstalk, J. "Extreme Plant Growth Enhancement as a Result of Co2 Fertilization" (2010).
Good one, Rattus.
ReplyDelete"Jack-in-the-Beanstalk" was also the first thing that popped into Horatio's mind when he saw the name Beenstock ... and Pippi Longstocking was the second thing.
Horatio actually commented over at Open Mind about the "(Jackinthe)Beenstock paper'
It's actually funny, in a pathetic sort of way. Some of this stuff is so ridiculous that it makes fairy tales seem real in comparison.
Hi Eli, It is windy and I kinda was blown off track... if I understand your science lingo,... you folks don't really know the 'Global Temp.'; but you can model it and "it" has increased less than a half a degree Fahrenheit, over the last ten years? Except of course this winter; which was caused by: Man-made-global-warming... Betrug!..., say it aint so, ya furry buck ya...
ReplyDeleteRabett seems to have changed his tune since 2007. Then, Essex et al. could do nothing right. Now; “We [agree] that a single global average temperature [is not] particularly meaningful to understanding global warming ...”. Implicit apology accepted, Rabett.
ReplyDeleteBut you go on to propose that subtracting one ‘not particularly meaningful’ annual temperature average from an 'even less meaningful' average of 10 ‘not very meaningful’ annual averages - to get a ‘temperature anomaly’ is less meaningless than one ‘not particularly meaningful’ annual temperature average?
Give me a break! I can't accept that logic. An ‘anomaly’ by any other name is still "the difference between one annual average and an average of 10 (or more) sequential annual averages", all of which are "not very meaningful”.
Unless you are suggesting that, somehow, the process of subtracting one meaningless thing from another decreases meaninglessness, or that adding meaningless things together decreases their meaninglessness, I am at a loss to grasp what you are trying to imply.
Secretly, I don't think you can believe it either - but you have to keep going now, or else admit you were wrong all along.
Essex constructed a misleading data set, from a small number of carefully selected (in the sense of selected to mislead) stations without accounting for seasonal changes. By improperly "averaging" temperatures rather than local anomalies to compare with each other they produced garbage.
ReplyDeleteOn the theoretical side whilst properly defining a thermal equilibrium to include radiation fields, they did not recognize that local thermodynamic equilibrium exists everywhere below ~100km, allowing us to measure temperatures wherever you stick your thermometer.
Eli still thinks it was spinach.
The ‘garbage’ result Eli mentions was partly the purpose of the exercise. Essex et al. used several different methods (including temperature ‘averages’) to illustrate a simple truth of thermodynamics:
ReplyDelete“A sum over intensive variables carries no physical meaning [in thermodynamics]. Dividing meaningless totals by the number of components [to give an 'average'] cannot reverse this outcome.”
You’re not going to argue that “Thermodynamics is bunk”, are you, Eli?
They are saying, in effect, “An average of two temperatures is a statistic, not a temperature”. It’s a bit like averaging “all telephone numbers, globally”; it can certainly be done, mathematically, and the result can be called “a statistic”, but it is still physically meaningless.
Remembering the fundamental properties of ‘intensive’ and ‘extensive’ variables may not be as exciting as “stick[ing] your thermometer ... wherever”, but the risks implicit in ‘forgetting’ these fundamental things are immense.
When more engineers also start ‘remembering’ their basic thermodynamics, the Global Temperature Anomaly will be seen for what it is: a scientific ANOMALY, with no physical power to influence the future weather in any locality. It may influence ‘the opinions of weather forecasters’, but I see no evidence that the weather (sorry, climate) has been taking much notice of them, it, or you. The weather will go on doing what it has always done, even before the invention of the wheel: Change!
Since 'weather' is to 'climate', as 'data' are to 'statistics', Mark Twain’s old adage might be better quoted today as: “Lies, damn lies and climate ‘science’.”
BS, three monkeys typing articles for the Journal of Thermodynamics can put together a million useless metrics. It takes some thought and work to put together a useful metric which can be tested against observation and modeling to validate both. Since both the theory and the observations are bounded by thermodynamics, why yes, Essex, McKitrick and their rented editor were either incompetent (something Eli can easily believe about the editor and McKitrick) or seeking to mislead.
ReplyDeleteOz Wizard was so shocked by the speed and vitriol of Eli’s reply that he fell backwards off his chair. As he was being rushed to ER by ambulance, he asked me to reply on his behalf.
ReplyDeleteFirst, let me translate what Eli seems to be saying into normal language, so we can resume a calm debate on the simple scientific point Oz was making:
1. “useless metrics” = ‘temperature averages’ used by Essex et al. to focus attention (successfully, in Oz’s humble opinion) on the ‘meaninglessness of temperature averages’ in thermodynamics;
2. “useful metric” = Global Temperature Anomaly devised by Eli’s monkeys (Jones, Briffa, Mann et al.); the difference between one global annual temperature average and the average of ten (or 30) preceding global annual temperature averages;
3. “thought and work” (al la Jones, Briffa, Mann et al.) = averaging temperatures taken from ‘wherever they stick their thermometers’ (includes tree-mometers, ice-core-mometers, etc.) after suitably massaging resulting data sets to make them “useful” [see 2, above];
4. “model[l]ing” = putting “useful” data into a computer program designed to prove that it is “useful” data [see 2, above].
You do see his point, don’t you Eli? It’s not about whether you like Essex et al. or the Journal of Non-equilibrium Thermodynamics, or what evil motives you think they might have had.
A point made in debate needs to be rebutted on its merits. The point is, “taking more averages of already meaningless averages will not make them less meaningless” (and neither will swearing; it just makes your face go red).
Fuddy Duddy,
ReplyDelete2. “useful metric” = Global Temperature Anomaly devised by Eli’s monkeys (Jones, Briffa, Mann et al.); the difference between one global annual temperature average and the average of ten (or 30) preceding global annual temperature averages
The monthly anomaly of each thermometer relative to the average monthly temperature of that particular thermometer over an homogeneous base period, combined with due areal weighting to give an average monthly global anomaly which can then be averaged seasonally or annually or by decade.
Fixed.
Elmer has vision issues.
ReplyDeleteNow that response was helpful. Elmer wants me to thanks you for adjusting definition 2 from ‘annual’ to ‘monthly’, and making your problem 12 times worse.
ReplyDeleteNow address the thermodynamic proposition posed by Essex et al., viz. The meaninglessness of ALL of the above AVERAGES of the monthly temperature averages used to determine the monthly anomalies (i.e. differences between one month’s average and the average of preceding monthly averages (how many? I’ll let you tell me), and of the anomalies derived from them by further seasonal, annual, or decadal averaging.
As statistics, those ‘averages’ (and anomalies) may all have relevance, but they are NOT temperatures. They may be relevant to how you think about the future, what you think the atmospheric machine might do, etc. But they still have no direct or implicit physical control over the temperature tomorrow (or next year, decade or century).
For one thing, the seasons change on a twelve month schedule most places, so you want to compare January temperatures to January temperatures in the same location, not to the June ones. When you do this, you find that the monthly anomalies don't have large swings.
ReplyDeleteFor another, since you build thermodynamics into the models, why yes, outputs are not thermodynamically meaningless, and can be compared to observations.
Did you meant "... so you want to compare January [temperature anomalies] to January [temperature anomalies] in the same location ..."??
ReplyDeleteI meant "mean" ...
ReplyDeleteEli wants to compare January to January, apparently Oz, being an upside down sort of guy, wanted to compare January to June, which essentially is what Essex did.
ReplyDeleteWhatever.
OK, let’s stay with your “January to January” comparison. You are talking about January anomalies in each case? [“Yes” or “No” will suffice].
ReplyDeleteAnd leave "June" out of it!
ReplyDeleteShe's a nice month. I didn't mention her, and neither did Essex et al. (except as the "in press" publication date - "June 2006").