If you testify in a court of law in the United States, you have to swear an oath to be honest. This oath requires you to tell the truth, the whole truth, and nothing but the truth. If you violate this oath in sworn testimony, you’re guilty of the crime of perjury: deliberately giving false or misleading testimony under oath.
Noel Sheppard, in his latest entry on the “Newsbusters” site, reproduces a graph prepared by Joe D’Aleo, whose work we have already examined. If Sheppard’s post or D’Aleo’s graph were sworn testimony in a court of law, I’d charge them with perjury.
The “evidence” provided in D’Aleo’s graph, which is the basis of Sheppard’s article, consists of surface temperature estimates from HadCRU (the HadCRUT3v data set), lower-troposphere satellite (MSU) temperature data (from UAH), and CO2 concentration (measured at the Mauna Loa atmospheric observatory):
When I plot the same data for the same time span, I get a very similar graph:
This graph is an example of the deceptive trick known as cherry-picking. Let me show you all the data in the HadCRUT3v data set, all the data in the UAH satellite lower-troposphere data set, and all the CO2 data from Mauna Loa; this is the whole truth:
Now let me show you testimony of Sheppard and D’Aleo; this is not the whole truth:
How astoundingly weak is their case, how deceptive are they, when their “testimony” omits over 90% of the data?
UPDATE:
A graph of 10-year averages of the HadCRUT3v data:
UPDATE #2:
A graph (from Brohan et al. 2006) showing the HadCRUT3 data, together with colored regions indicating the size of the individual components of the uncerainty, for the globe:
203 responses so far ↓
Hank Roberts // April 16, 2008 at 2:34 am |
It’s puffery.
Raven // April 16, 2008 at 2:37 am |
Tamino,
The climate of the earth has always changed an always will change this means that picking any starting point represents an exercise in cherry picking. In your case, you cherry picked a start point that makes the rise look as dramatic as possible.
In fact, I would say you choice of start point is more misleading than D’Aleo’s because you try to imply that the entire rise is due to humans. You also imply that the historical record is accurate and that temperatures really rose 0.8 degC of that period. A better presentation would include realistic error bars on historical temps.
[Response: Hahahahahaha!!! What are you, new?
For these graphs, I plotted all the available data. That's the whole truth.
I often start my trend analysis with 1975 because completely objective mathematical analysis indicates that that's a "turning point" in temperature data. In other words, I don't "pick" a starting point at all, I let the numbers do the talking. Unlike D'Aleo & co., I don't tell the data what to say -- I listen to what they're telling us.
As for claims that the historical record isn't accurate, that's the last refuge of scoundrels: when the data don't say what you want them to, start slinging mud on the data.]
DrCarbon // April 16, 2008 at 2:44 am |
Very impressive. Now, were such cherry picking to be accompanied by a mechanism that negated 100 years of physics then we’d be on to something!
Raven // April 16, 2008 at 3:36 am |
Tamino,
You did not plot all of the available data. We have temperature data going back to the 1700s in parts of Europe (which is comparable to today) and we have various sorts of proxy data going 1000s of years. Plot a trend from the Holocene Optimum and you would see a cooling trend. Call it what ver you want but it is still cherry picking to make the point that you wish make.
I also said that failing to plot the data *with appropriate error bars* is misleading because you leave the impression that the historical record is more accurate than it is. Your assertion that we know the global temperature in 19o0 to 1/10th of degree is quite ridiculous.
Your claim that 1975 represents some sort of turning point is amusing because it shows that you acknowledge that trends can change. It is pretty clear that 2002 could be another turning point but we won’t know for certain for another 5-10 years.
Hey. I don’t have any problem with you presenting your graphs and claiming that your cherry picking is better than D’Aleo’s. However, throwing around terms like ‘perjury’ is completely uncalled for given the flaws in your own analysis.
[Response: I didn't pick the data sets. It was D'Aleo who chose HadCRUT3v, UAH-MSU-TLT, and Mauna Loa CO2. But he left out almost all of it. I didn't.
It's typical denialist fare to say "2002 could be another turning point but we won't know for certain for another 5-10 years." Last Thursday could be another turning point -- when will you start on that one? I won't talk about more turning points until there's some *evidence*.
The claim that temperatures back to the 1700s in Europe are "comparable to today" is just more perjury, rather like most of your claims. As for error bars -- go tell Noel Sheppard and Joe D'Aleo to plot 'em.
It's amazing how desperate liars get when they're caught.]
trrll // April 16, 2008 at 3:46 am |
Do you really need error bars? Error bars are valuable when you are showing a limited number of data points, and you have other information that tells you how much error there is likely to be in those values. But with this amount of data, anybody with any kind of statistical experience can pretty well “eyeball” the data and get a good idea of how much high frequency noise there is. It is easy to see, for example, that the 1998 peak is a spike of high frequency “noise” superimposed on a much slower upward trend. Similarly, it is easy to see that the level of noise is such that it would be hard to accurately judge the overall trend for a time period shorter than about 20 years or so.
[Response: Bingo!]
cce // April 16, 2008 at 4:19 am |
The HadCRU analysis has error bars that are close to ~0.4 tall in 1850.
http://www.metoffice.gov.uk/research/hadleycentre/CR_data/Monthly/HadCRUGNS_3plots.gif
The NRC panel concluded that “most but not all” proxy indicators show that modern warmth has not been exceeded in 2000 years.
The Central England temperature series can be seen here.
http://hadobs.metoffice.com/hadcet/graphs/HadCET_graph_ylybars_uptodate.gif
I’ll leave it to those of us who posess the gift of sight to decide when temperatures were the highest in those records.
nanny_govt_sucks // April 16, 2008 at 4:20 am |
I don’t think I understand your choice for the CO2 Y-axis. It looks like you’ve specifically chosen range values to get the CO2 to line up exactly with the temperature chart. Isn’t that a bit misleading? Can you show the CO2 as an anomaly just as you’ve done with temperature?
Dano // April 16, 2008 at 4:21 am |
Raven is new, give him a break. He isn’t aware of the long list of denialist rhetoric that has been sifted thru here.
He may be, however, aware of this list, which he is a part of, that details the non-distracting, mischaracterizing or hand-waving excuses so far offered by denialists for their not being able to provide evidence to back their claim. Wanna be sweet 16, Rave?
Best,
D
Dano // April 16, 2008 at 4:22 am |
Hmmm. Forgot about the snap preview. I’ll forego TinyUrl in the future. Apologies.
D
nanny_govt_sucks // April 16, 2008 at 4:27 am |
Or use the same scale that D’Aleo used.
Simon D // April 16, 2008 at 4:41 am |
The irony (to me) is that D’Aleo and others criticize climate models, but their work shows just why we need those models. What they have done is develop a model that is far too simple – monthly Temp ~ monthly CO2 – to explain the system. It is only by considering other processes, whether in theoretical models or actual computational models, that we can learn how the climate system actually works.
John N-G // April 16, 2008 at 5:22 am |
Another not-so-subtle subtlety: the overlay of CO2 and T on one graph requires choosing a relative scale. In D’Aleo’s plot, 5 ppb = 0.2 C. With this scaling, the CO2 and T curves would be expected to line up if the climate sensitivity is about 12 C per CO2 doubling, with no lag in the climate system!
T/HB’s scaling on the 1500 yr plot is much closer to the more widely accepted values for CO2 climate sensitivity, including a time lag. Apply that scaling to D’Aleo’s chart, and the CO2 curve only goes up from the equivalent of 0 C in 1998 to 0.17 C in 2008. Voila, the slopes of T and CO2 look much more similar.
Most of the deception in D’Aleo’s plot is from applying an absurd relative scaling of T and CO2.
Zeke // April 16, 2008 at 5:56 am |
I notice that both Noel’s graph and your reconstruction of it appear to plot UAH and HadCRU temperature series on different baselines (1979-1998 for UAH and 1961-1990 for HadCRU). Adjusting for that should give you a much greater difference in 1998 and a greater overlap over the rest of the period, and would look like this:
http://i81.photobucket.com/albums/j237/hausfath/UAH-HadCRU.jpg
Its nitpicking (and may have been purposeful on your part to recreate the original graph), but should be pointed out.
fred // April 16, 2008 at 6:26 am |
This is an example of the rhetorical silliness that poisons debate on AGW. How exactly is showing a subset of the available data telling an untruth? I do not know this D’Aleo, but what he seems to have done is show a set of correct data, and then probably drawn some mistaken conclusions from it. Perhaps his conclusions were mistaken because he showed too little data? Happens.
It would be far more productive to abandon all the silly rhetoric and just point out that you would not expect short term CO2 fluctuations to correspond to short term temperature fluctuations.
That is rather obvious, but its unfortunately a one liner.
sdw // April 16, 2008 at 6:40 am |
The irony is that the ‘complete’ HadCRUTv3 data show how ‘normal’ the recent warming trend appears. The rate of change is almost equivalent to the first part of the century. Low pass filter the data and look at the derivative to convince yourselves.
regards, sdw
Pete // April 16, 2008 at 8:04 am |
I don’t see how this is different to those who publish studies of the Sun and then trumpet the claim “no sun link to climate change” (ie the F&L study from 1985 to 2005). 20 Years, are you serious!
Cherry Picking is rife, so it would seem. Just as you showed in your ‘Cycles’ thread that it is bad science from all parties, then so is this example from all sides as well.
I hope you apply your apparently higher standards than everyone else on the Planet to your future work in here. Lead by example!
Tuukka Simonen // April 16, 2008 at 8:12 am |
Dude, you’re being so mean to those poor people! I love these short very well argumented posts.
As a whole, I think your blog is the best climate blog on the net; easy to understand and very interesting. Also, poor argument bashing is something which you never get bored. However most of the bashing need more effort, this was an easy one. :)
I keep a similar climate blog (with much less knowledge) in Finnish and I get great material from your blog. Thank you for this post and for your blog as a whole!
Julian Flood // April 16, 2008 at 8:44 am |
Re Response to Raven:
quote For these graphs, I plotted all the available data. That’s the whole truth.
I often start my trend analysis with 1975 because completely objective mathematical analysis indicates that that’s a “turning point” in temperature data. In other words, I don’t “pick” a starting point at all, I let the numbers do the talking. Unlike D’Aleo & co., I don’t tell the data what to say — I listen to what they’re telling us. unquote
Have you carried out your — difficult to know what to call it — ‘listening exercise’ on other data? I’d be interested to hear what you… err… hear from Hadcrut SSTs without the Folland and Parker correction. I thought you’d have to allow large error bars at the beginning — the graph starts in 1850 — but, if trrll is correct then that is not a problem.
Eyeballing — or, as some would have it, cherry-picking — I see* a marked change in 1910. By your argument above that would indicate a good time to start measuring warming. An inexorable .14 deg/decade with an upward excursion in the 40s. Is that what you hear?
Perhaps you could you give some indication of the mathematical process you use — in general layman’s terms, nothing too rigorous — or is the maths too complex to summarise?
JF
*Sorry, ‘hear’.
Adam // April 16, 2008 at 8:49 am |
Just as an aside, it’s worth noting that the graph of the Had/CRU data (at least) is plotted with error ranges on their website. Hard to see how you’d be able to use them to get rid of the long-term rise in temps.
http://www.metoffice.gov.uk/research/hadleycentre/obsdata/HadCRUT3.html
Tom Woods // April 16, 2008 at 9:00 am |
Tamino said:
“As for claims that the historical record isn’t accurate, that’s the last refuge of scoundrels: when the data don’t say what you want them to, start slinging mud on the data.”
—–
Should that not be “doesn’t say what you want them to?
You’re a liar, Tamino, and your grammar is horrible! (/satire)
Okay, back to reality.
Nice repsonse and nice post. You are the path of enlightenment, my friend.
I must also ask you if you have come across anything to sea-level/temperature feeback. I still contest that 15-20% of the global temperature rise from ice age to hypsythermal is due to the feedback of rising sea-levels. Perhaps your mathematical wizardry could write up a quick post in a follow up to your feedback post. Sea-level plus 400 feet would be equal to elevation minus 400 feet (in addition to exposed continental shelf now moderated by the sea) .
I still have yet to see this aspect of feedbacks explored.
The Tuatara // April 16, 2008 at 11:49 am |
Thanks, HB. d’Aleo’s graph crops in submissions made by our Kiwi cranks to hearings on Emissions Trading Scheme legislation in the NZ Parliament. Useful to be able to demonstrate the clear cherry pick.
Ta.
dean_1230 // April 16, 2008 at 11:59 am |
Tamino,
I doubt you’d ever get a perjury charge to stick in this case, mainly because you’ve wrongly defined perjury. Is the chart in error? are the data points misplotted and more importantly, misplotted on purpose?
If the data is correct, it’s up to the lawyers to delve into the meaning. For D’Aleo to be charged with perjury, you’d have to show that he willfully manipulated the data he presented. You didn’t do that here. He CANNOT be charged with perjury for data he didn’t present.
[Response: The stated definition of perjury comes straight from the dictionary. It includes not just "false" but also "misleading," and I'd say they're being deliberately misleading.]
wolf // April 16, 2008 at 12:18 pm |
The AGW theory requires that temperatures rise as a result of increasing levels of CO2 in the atmosphere. The earth receives energy from the sun, some of which is reflected into space and some retained by atmospheric CO2.
Despite increasing amounts of CO2, the temperature has remained more or less stable in the last 10 years. In order for the theory to be true – there must be some explanation of where the energy went. It is not in the land temperatures, ocean temperatures or the atmosphere. Where did it go?
[Response: When you people are pinned down you'll try anything to wiggle out of admitting the truth. Speaking of wiggles, I guess you're one of those who denies the existence of noise in the climate system. You can't defend one denial of truth by resorting to another.]
Alan Woods // April 16, 2008 at 12:28 pm |
cce – Tamino’s post is about misleading graphs of cherry picked and truncated data. The CET record you linked to is similar – it leaves out the previous 100 years of the record and the warm 1730’s.
[Response: The 1730s weren't even close to as warm in the CET record as modern times. Must I graph them all?]
dean_1230 // April 16, 2008 at 12:41 pm |
No, they are presenting data… It’s up to the lawyers to ask about the holes in the data. For example, D’Aleo would state under oath that “the chart shows that since 1998 there’s been no warming”. That’s not a lie. there’s been no warming. But it is up to the cross-examination to ask about whether 10 years is significant… or whether the data is cherry-picked.
If D’Aleo is asked whether 10 years is considered “climate” as opposed to “weather” and he says “yes”, then THAT’S wrong. If he does so in an effort to mislead, then that’s perjury.
Showing a chart and leaving it up to the lawyers and jury to spot the hole in it is NOT perjury.
wolf // April 16, 2008 at 1:09 pm |
The laws of physics don’t take 10 years off. You made no attempt to answer the question.
[Response: Noise in the climate system doesn't take 10 years off either. Noise from denialists doesn't take 10 minutes off. Wiggle wiggle wiggle.
We've seen wiggling of global temperature ever since we started measuring it. It has always wiggled, it always will. Don't you know that energy is constantly exchanged between land, air, and sea, including not only the upper ocean layer but the deep ocean as well? That energy is required for the melting of ice and snow? Come to think of it, questions about "where does the energy go?" usually come from those who don't know beans about the energy budget.]
Tom C // April 16, 2008 at 1:12 pm |
What a lot of wasted words. Look, the last ten years of surface data don’t amount to anything conclusive. But, they are suggestive. If the current trend continues for another 5 years we will have a lot to argue about. Another 10 years and AGW alarmism is dead.
It should also be pointed out that most skeptics, such as myself, fully expect modest continued warming from CO2 for the next 50 years, but don’t think it is a cause for alarm. Even if the curve heads north again, it doesn’t prove the cause for alarmism.
climatewonk // April 16, 2008 at 1:38 pm |
My interest in this is the effect the debate over climate has on public policy, public opinion and policy makers so this kind of analysis is very signficant. When people like D’Aleo and others present cherry-picked data and base their analysis on it, claiming that global warming “stopped” in this or that year, or is negated, etc., many laypeople are unable to do a sound critique of the evidence presented to them and evaluate the conclusions. They may be swayed by bad science or pseudescience — graphs look professional, statistics convincing — unless you understand them, that is.
It is necessary to show that the work is flawed and why so that people can learn how to judge data.
So, no, not just a one liner.
Leif Svalgaard // April 16, 2008 at 1:40 pm |
HB, there is some cherry-picking in your graph as well. Namely the zero-point and scale-factor for CO2. To compare with D’Aleo you should have used his choices, not rescale to make the CO2 curve magically match the Temperature. THAT is cherry picking too. May not rise to the level of perjury, but is intended to be ‘leading’ the eye and mind at least.
[Response: Baloney. The match isn't "magical."]
dhogaza // April 16, 2008 at 1:41 pm |
Yes, they suggest three things:
1. The system is noisy. The AGW hypothesis does not predict that climate will suddenly become a noise-free system.
2. El Niño is real. The AGW hypothesis does not predict the end to El Niño.
3. La Niña is real. The AGW hypothesis does not predict the end to La Niña.
Goalpost move.
HB’s post doesn’t attempt to answer the question “will anthropogenic warming be harmful over the next 50 years”.
HB’s post is answering the question, “are these two people lying sacks of organic brown matter”, and the answer is, “yes”, as is anyone who starts an analysis beginning with the El Niño year of 1998.
I also question the accuracy of your statement. The flood of “global cooling has started …” and “global warming ended in the year …” crap we see from the denialsphere would argue against your claim that “most skeptics … fully expect modest continued warming from CO2″.
Leif Svalgaard // April 16, 2008 at 1:48 pm |
HB: “The match isn’t “magical.”" Agreed, poor choice of words on my part. I should have said ‘carefully picked’ or, perhaps, ‘cherry picked’.
[Response: Baloney! D'Aleo tries to show that the rise in CO2 doesn't correspond to a rise in temperature -- by displaying such a short time span that the trend in temperature is eradicated. I showed that it *does* -- by displaying all the available data.]
George // April 16, 2008 at 1:54 pm |
There is one more thing on that D’Aleo graph that is inaccurate/misleading.
It shows the atmospheric CO2 concentration (in ppm) rather than the radiative forcing due to the CO2 increase.
The temperature change is directly proportional to radiative forcing change, not CO2 concentration change and forcing increases less steeply with time (has a lower slope) than the CO2 concentration.
So by using concentration rather than forcing in their graphic, D’Aleo has accentuated the difference in the slopes.
[Response: If you want to do a realistic comparison, you'd also have to account for the lag in temperature response due to the thermal inertia of the oceans, and you'd want to estimate *all* forcings, not just CO2. But that would be dangerously close to actual *science*.]
Phil. // April 16, 2008 at 2:07 pm |
“HB, there is some cherry-picking in your graph as well. Namely the zero-point and scale-factor for CO2. To compare with D’Aleo you should have used his choices, not rescale to make the CO2 curve magically match the Temperature. ”
Tamino, logically the correlation with CO2 should be with log(CO2), how does that plot look for this data?
wolf // April 16, 2008 at 2:08 pm |
Still no answer to the physics question. 10 years is not significant in terms of overall climate variability. But it is significant in terms of the AGW theory.
[Response: What part of "deep ocean and cryosphere" don't you get? What part of "10 years is too short to reveal trends" don't you get?
If you're convinced that 10 years is significant in terms of the AGW theory, try looking at a graph of 10-year averages of global temperature. But that would make your premise look ridiculous.]
J // April 16, 2008 at 2:14 pm |
There are two issues here. One, which Tamino focuses on, is the cherry-picking of dates. But there are about a zillion examples of this, so the novelty value is minimal.
The more interesting one is John N-G’s point (about the Y-axis scaling). Obviously, Mr D’Aleo has scaled the Y-axis inappropriately, but it’s not always obvious what is the best way to visualize two variables with different units.
To do this right, you really need to first log-transform the CO2 data, because of the logarithmic relationship between CO2 and temperature. (This is why climate sensitivity is derived for a doubling of CO2….)
Just for fun, I took the Mauna Loa CO2 data and the HADCRUT temperature data, log-transformed the CO2 data (base 2), and did a simple linear regression. This assumes that there’s no time lag, which is obviously false, but whatever. Over the whole time period of the ML CO2 data (1958-2008) it shows a temperature sensitivity to log CO2 of 2.24 C/doubling. For D’Aleo’s cherry-picked period, it’s much smaller (0.15 C/doubling). For 1975-present, it’s 2.75 C/doubling.
Again, these are obviously underestimates, because they don’t account for a time lag in the temperature response.
J // April 16, 2008 at 2:18 pm |
Oh well, it looks like a several other people made the same points while I was composing that. I always was a little slow … sorry!
Joel Shore // April 16, 2008 at 2:19 pm |
Leif: As John N-G pointed out, the scaling used by D’Aleo is deceptive in that the temperature would only track CO2 on such a plot if the transient climate sensitivity were somewhere north of 10 C. (He says 12 C; I estimated 10.something C…Since really the dependence of forcing on CO2 is expected to be logarithmic, the exact answer is not precisely defined but is unambiguously in that generally neighborhood.)
So, in fact, the choice that D’Aleo made for the relative scales of those graphs for temperature and CO2 is very deceptive (although that part may more be due to ignorance rather than purposeful deception). Tamino’s choice of scaling, where the graphs would be expected to approximately align if the transient climate sensitivity is about 2 C, is much more in line with the estimates of what the transient climate sensitivity actually is.
Joel Shore // April 16, 2008 at 2:25 pm |
wolf: If you looked at plots from individual runs of climate models under a constantly increasing CO2 forcing, you would see the same sort of ups and downs that you see in the actual climate record. (See, for example, Stott et al., Science, Vol 290, op. 2133, Figure 1.) Thus, your claim that the AGW theory predicts that the temperature be steadily monotonically increasing under a monotonic increase in the CO2 forcing is provably false.
Mike B // April 16, 2008 at 2:35 pm |
Atmoz did an intersting correlation of CO2 vs HadCRUT temperatures a couple of months ago, got an R value of 0.725 since 1958.
Also compared NINO, PDO, and NAO indexes against temperature again after standardizing all of them. Not surprisingly none of them correlated well on the longer term.
http://atmoz.org/blog/2008/02/10/on-the-correlation-between-temperature-and-climate-indices/
Leif Svalgaard // April 16, 2008 at 2:36 pm |
HB, repeating ‘baloney’ is committing the fallacy of repetition. Don’t get me wrong, I also think that the D’Aleo graph is junk, but we [you] should not commit cherry picking either when you don’t have to. And no matter how many times you say ‘baloney’ the match of CO2 and temperature on your graph did not happen by accident, its visual impact was certainly enhanced [to bring the point across, I guess] by scaling CO2 to match T. This is also cherry picking for effect as it assumes [which may or may not be true] that ALL the change in T is due to CO2.
[Response: I didn't do any cherry picking at all and your repeating it doesn't make it true; the fallacy of repetition is yours. Wikipedia defines cherry picking as "the act of pointing at individual cases or data that seem to confirm a particular position, while ignoring a significant portion of related cases or data that may contradict that position." I specifically showed ALL the data for all three of D'Aleo's selected variables.
As for choosing the scale so that the graphs match, if we correlate one variable with another *that's what happens*.
Your entire argument seems to me to be extremely disingenuous.]
Mike B // April 16, 2008 at 2:43 pm |
Leif,
Is the choice of scaling not more or less arbitrary? One could scale CO2 in such a way that the line appeared flat in comparison to temperature.
Tamino’s choice for scaling makes more physical sense than D’Aleo’s. And regardless of scale there is long term (50 year) correlation with CO2 and temperature.
cce // April 16, 2008 at 2:46 pm |
There have been many words written about the AGW signal being “about 0.20 degres per decade.” Stated another way, it is about 0.02 degrees per year. AGW is buried under noise with short time periods, but that didn’t stop temperatures from rising 0.5 degrees over the past 3 decades.
The reason that the 1998 record hasn’t been broken in most analyses is because it was an absurdly warm year — well beyond anything predicted by AGW alone. 2005 is either the warmest year, or second warmest year. Every year since 2001 is warmer than all years prior to 1998.
As for Central England, anyone can download the data and plot it for themselves. 2006 is the warmest year on record, and recent years are warmer than any comparable time in the 1700s (apparently, the “Little Warm Period.”)
http://hadobs.metoffice.com/hadcet/cetml1659on.dat
wolf // April 16, 2008 at 3:08 pm |
What part of “deep ocean and cryosphere” don’t you get?
Where is the supporting data?
[Response: The cryosphere is shrinking, rapidly; the evidence is everywhere, if you dispute it you're only fooling yourself. As for the deep ocean, we don't have data that I'm aware of, but riddle me this: do you really believe the deep ocean doesn't warm in response to an increase of energy entering the planet?
As for surface temperature, when the same wiggles are observed over the last decade that we've seen ever since we started measuring, where do *you* think the energy comes and goes?]
Neil B. // April 16, 2008 at 3:08 pm |
Raven, and like minded skeptics: Your complaints about “you too” cherry picking from advocates of AGW ring hollow because you are ignoring the theoretical reasons why recent AGW should logically be correlated to increased average warming. (Not only that, but the relevant region to pick from would be the combination of significant CO2 rise and good data, which we have for the last few decades and which was shown here. There is noise too, and ten years isn’t really enough to iron that out, but thirty or so is much more convincing.) We already knew that the Earth went through various cycles and has been colder and warmer in the past, the point is that we know that CO2 absorbs IR and should stimulate warming (would you deny that it and other gases are “greenhouse gases” even if you don’t think they are sufficiently efficacious? At least Lumo for example will admit that much.) Hence, it isn’t just a matter of wondering if one trend correlates with another one, in a causal theoretical vacuum. That would be pure statistical analysis, and that’s not the only available tool here.
The first significant deep treatment of how increasing CO2 should warm the Earth was written way back in 1896 by future Nobel winner Svante Arrhenius. Al Gore wasn’t around to press him into writing it.
Hank Roberts // April 16, 2008 at 3:09 pm |
Good list there, Dano.
Pity about what’s happened to dot.earth.
P. Lewis // April 16, 2008 at 3:13 pm |
The annual average CETs for the warm decade 1730 to 1739 are 10.04, 9.85, 9.69, 10.47, 9.8, 9.54, 10.3, 9.92, 9.81, 9.2°C respectively (decade av. = 9.862).
For comparison, the 1990 to 1999 annual average CETs were 9.52, 9.86, 9.49, 10.24, 10.52, 9.2, 10.53, 10.34, 10.63°C respectively (decade av. = 10.096).
The decades either side of 1730-1739 were much cooler. For decades ending 1719, 1729, 1749, 1759, 1769 the decadal averages were 9.153, 9.307, 8.854, 9.042, 9.058°C respectively.
For “decades” ending 1969, 1979, 1989, 2008 (latter, 8 years only), the “decadal” averages are 9.277, 9.539, 9.518, 10.4448°C (latter, 8 years only) respectively.
Leif Svalgaard // April 16, 2008 at 3:19 pm |
Mike B and HB: You would have gained the high ground by simply extending D’Aleos’s graph to include ALL the data [HB, do that] without changing anything else. Also changing the scale [to one that make the two curves match] goes beyond that.
[Response: I certainly included all the data -- that's the point -- and if I'd kept the same ridiculous scale as used by D'Aleo the range of the temperature axis would be so large that it would compress the temperature time series, giving a very *false* impression of the temperature trend -- very much like the misleading tactic which is at the root of D'Aleo's presentation.
Your insistence that I apply a misleading relative scale between the variables is further evidence that you're being extremely disingenuous.]
P. Lewis // April 16, 2008 at 3:32 pm |
Danforth, in Arthur Miller’s The Crucible, says:
And from the ‘Lectric Law Library’s Lexicon on perjury:
The question then becomes whether the likes of the aforementioned in the OP would wish it to be known that, if found hypothetically guilty, they were hypothetically perjurers or were just incompetents if a case came before some court or body in which an oath is taken and they were found wanting. Such an outcome would seem to me not to be particularly beneficial to their advocacy (though I’m fairly sure that that would not affect how the vast majority of their acolytes would view their probity and knowledge one iota!).
Of course, unless one ends up in court (say, because of libel or slander) or presumably in some Congressional testimony (?), then this situation, re perjury, is unlikely to be tested.
wolf // April 16, 2008 at 3:36 pm |
Joel – ok, agreed – poor articulation on my part.
What I was trying to say – is that if the temperatures are stable – that AGW requires the energy to stay within the earth. There should be a signature – either by increased land and ocean surface temperatures, increased temperatures within the ocean, or increased atmospheric temperatures.
Where is the signature in the last 10 years?
[Response: Where's the signature in the last 10 days?
Your entire argument is nothing more that a thinly veiled claim that there's no noise in surface temperature, so it has to show a "signature" no matter how short a time span is chosen. The global temperature time series has been noisy since we started measuring it, it was noisy before we started measuring, and it will remain so for all time.
As for the last decade, that *starts* at the peak of a giant el Nino -- when heat was transferred to the atmosphere *from the ocean*. It wasn't a sudden increase of total energy in the earth as a whole, it was a sudden exchange of energy between earth subsystems, with energy being deposited in the part which we measure as surface temperature.]
Bob G // April 16, 2008 at 3:54 pm |
Tamino,
You mention the importance of accounting for the lag in temperatures due to the thermal inertia of the oceans. I have never seen this calculated, only grossly estimated. Looking at the GISS ocean/land temp graph provided in the handy links at the top of your home page (climate data links/NASA GISS/graphs/page down to land-ocean), there is no evidence in these non-statistically trained eyes of any lag in ocean temperatures when compared to land temperatures. The ocean temperatures are muted, with rates of warming and cooling at roughly half of the land values. But both land and ocean temperatures were at a low point around 1910, rose to a high point in the mid 40s, dropped a bit to the mid-late 70s and rose thereafter. Where is the evidence of a lag? Should it be apparent in this 127 year record?
[Response: The lag due to thermal inertia of the oceans doesn't mean that the oceans will warm later than the atmosphere. It means that the full response of the system is delayed because it takes so long for the oceans to warm compared to the atmosphere. The evidence that this is actually happening *is* that the rate of ocean warming (and cooling) is less than the rate of land/atmosphere warming.]
P. Lewis // April 16, 2008 at 4:07 pm |
Added to the legal situation above, there also is the issue of professional misconduct.
Should anyone affiliated to a professional body or academic institution transgress their professional codes of conduct or ethics, especially when dealing with the public, then they can be held answerable to that body.
For example, “Article XII. Guidelines for Professional Conduct” of the American Meteorological Society’s (AMS’s) Constitution (20 January 2008) states the following (any emphasis is mine):
And this set of AMS guidelines is quite wishy-washy compared with my former institute’s guidelines on professional misconduct and bringing the name of the institute into disrepute. In fact, my former institute expressly expects its members to notify “of any significant breach of the Rules for Professional Conduct by another member and should seriously consider reporting another professional with whom they may be professionally connected, to their professional body if he or she appears to be breaching the general principles of ethical practice and who is likely to bring the profession into disrepute”.
What would you do if you saw a brother/sister member acting in a fashion so as to sully the name of your body/institute? Report or not?
I’m surprised this has not (to my knowledge) surfaced in this age of the blogs (other than in some companies not looking favourably on some employees’ blog comments on their employers leading to employee dismissals) — ah, perhaps I can think of one possible case.
Now, innocent until proven guilty in such cases of course, but I know of one AMS fellow and council(l)or who publishes in the public domain who might conceivably be considered to have fallen foul of articles 3A, 3B, 3D and 3E in some respects. Whether such an actual transgression of rules of professional conduct (or ethics) is considered to have taken place, though, is wholly the responsibility of the particular governing professional body. What would I do?
DrCarbon // April 16, 2008 at 4:08 pm |
Hey Tamino,
A minor quibble. Could you start labeling your axes? It’s good practice – I’ve noticed a lot of failure to label esp. y-axes for the crowd that advocates post 1998 cooling. By failing to label they can draw attention to perceived trends rather than absolutes. Be nice to show them how it’s done correctly.
David B. Benson // April 16, 2008 at 4:36 pm |
cce wrote “There have been many words written about the AGW signal being ‘about 0.20 degres per decade.’” I contrast this with the warming/cooling during the Eem of 0.23 per 50 years, i.e., 0.046 per decade.
I posted regarding the Eem and ‘natural climate variability’ on the Open Thread yesterday, but nobody seems to have any comments. :-(
Oh yes. I chose to start with the Eem since there was no anthropogenic influence (worth mentioning) then…
Leif Svalgaard // April 16, 2008 at 4:52 pm |
HB: D’Aleo’s temperature scale differs from yours by a factor of three [relative to the CO2]. Maybe he [as many others of his ilk] has a different opinion on the sensitivity of T to changes in CO2. That is certainly allowed, or maybe the whole issue is that he isn’t allowed to disagree? I do, obviously, agree with you that one should show ALL data and that he is being dishonest by not doing so, but I do not agree that he is not allowed to select another sensitivity without being accused of giving a “false” impression. And that is my point.
[Response: I never claimed, never even hinted, that he was dishonest for his choice of relative scale between temperature and CO2 axes, only that he was dishonest for leaving out all but a tiny fraction of the data so he could avoid the part that contradicted his claim (which is the *definition* of cherry-picking). *You* claimed that *I* was dishonest for *my* choice of relative scale between the axes. That ain't right.]
Leif Svalgaard // April 16, 2008 at 5:17 pm |
HB: I never claimed that you were dishonest just that you cherry picked a sensitivity that was your favorite and not his. He is allowed to pick a sensitivity that he likes without being accused of given a *false* impression.
trrll // April 16, 2008 at 5:34 pm |
Apologies from previous fragmentary post.
They say that there is no such thing as a stupid question, but this comes close. Virtually all of the energy received from the sun is radiated back into space. This has to be the case, or the temperature would increase. The fact that there is a long-term upward trend in temperature indicates that a very, very tiny fraction of the total is being retained. As the average temperature increases, the average amount of energy radiated to space will increase, until ultimately a new steady-state is established at a higher temperature.
Any kind of energy accounting has to consider not just temperature, but all forms of energy, including the kinetic energy in winds and ocean currents and the chemical potential energy of all the forms of matter on earth. For example, if you put energy into a mixture of ice and water, you will affect the ratio of ice to water, but you won’t affect the temperature at all. You may have noticed that we have ice and water here on earth.
Moreover, there is no reason to expect incoming solar energy to have a constant impact on temperature. Light energy that is reflected from clouds will have much less impact on temperature than light that is absorbed by earth and eventually re-radiated as lower-energy infrared. So such things as cloud cover are going to produce short term (“weather”) fluctuations in temperature even if the amount of solar energy falling upon the earth is absolutely constant.
J // April 16, 2008 at 5:38 pm |
Leif writes: “He is allowed to pick a sensitivity that he likes without being accused of given a *false* impression.”
A little consistency would be good. If Mr D’Aleo really believes that climate sensitivity is on the order of 10-12 C per 2XCO2, it would be nice if he would say so explicitly. I doubt that any more than a minuscule fraction of his readership understands the implications of his graph.
Joel Shore // April 16, 2008 at 5:44 pm |
Leif: Now that’s just silly…It is very disingenuous of him to implicitly choose a transient climate sensitivity of about 10 or 12 C by his relative choice of axes. If he honestly believes that this is a reasonable estimate of climate sensitivity, then he belongs in the “super-alarmist” camp not the “skeptical camp”…and when the climate then fails to follow his expectations all that it shows is that his expectations were whacked, not that CO2 doesn’t have the affect on climate that most people think it does. So, I would expect Aleo to be hopping mad about the abuse of his graph to claim something with no relation to what we might charitably say he was trying to show.
Sometimes, when you are in hole, it is best to stop digging by just admitting you are wrong.
Joel Shore // April 16, 2008 at 5:55 pm |
By the way, it is important to note how the poor choice of the relative scalings of the CO2 and temperature axes is vital to the visual effect of Aleo plot. To see this, just mentally picture what his plot would look like if the CO2 line, instead of going between about 0 and 0.8 in reference to the temperature axis instead went from about 0 to 0.015. Then, it would be immediately visually apparent that the noise in the temperature plot over this time period is too large to tell whether the trend in the temperature plot disagrees with the trend in the CO2!
Lee // April 16, 2008 at 5:58 pm |
“They say that there is no such thing as a stupid question, but this comes close”
I think I’ve said this before here – the professor who taught me to teach well used to say that every good teacher tells his students one lie – that there are no stupid questions.
L Miller // April 16, 2008 at 5:59 pm |
Putting aside the fact he cherry picked a limited data set, the problem with what you are saying is that D’aleo choice of CO2 sensitivity is exceptionally high. He is setting up a strawman and showing that warming is below that exceptionally high CO2 sensitivity therefore “proving” CO2 isn’t causing the warming.
Even if he hadn’t cherry picked the data set and accounted for lag all he could have show with that scale choice is that CO2 sensitivity is below 10-12 deg. This is clearly a strawman since no one seriously believes sensitivity is that high. Under those circumstances it’s rather ridiculous to expect HB to stick to that choice of scale.
L Miller // April 16, 2008 at 6:07 pm |
Sea level rise due to thermal expansion is directly proportional to the total energy in the ocean and has continued to increase in the last decade. Since the oceans hold over 90% of all the energy in the earths climate system this is a very strong indication that energy has continued to increase.
Leif Svalgaard // April 16, 2008 at 6:10 pm |
Joel: “By the way, it is important to note how the poor choice of the relative scalings of the CO2 and temperature axes is vital to the visual effect of Aleo plot.”
But the very same is true of the Tamino plot. I don’t know what scaling D’Aleo likes, and I don’t really care, my only point was that if D’Aleo had plotted ALL the data even with his screwy scaling he could not have been guilty of perjury, no matter how bad his scaling was. But changing the scale because otherwise the Figure would give a *false” impression, that “ain’t right”. If the D’Aleo plot with the D’Aleo scaling, but with ALL the data, would look ridiculous, so more the better for people that disagree with him.
P. Lewis // April 16, 2008 at 6:23 pm |
PS. There appears to be an HTML gremlin abroad. That was meant to be 2008 followed by a closing parenthesis, not a smiley.
dhogaza // April 16, 2008 at 6:36 pm |
If his claim is that his graph disproves IPPC projections based on a roughly 3C forcing per CO2 doubling then, yes, it’s perjury, because his graph shows no such thing, because his scale reflects a 10-12C forcing. That’s not a figure that enters into the scientific argument.
It’s no different than saying “the IPCC is wrong because global temps haven’t risen by 30C this past year”, or “the IPCC is wrong because the greenland icecap hasn’t melted this year”.
dhogaza // April 16, 2008 at 6:41 pm |
Leif, consider that one could cause that line to be virtually flat no matter what level of correlation exist by choosing an unrealistic forcing level.
IPCC predicts 3C per doubling, and long term trends track that? You can prove they’re “wrong” by choosing a y-scale for CO2 concentrations that corresponds with a forcing of (say) 100C.
And you’d say that presenting this as “proof” that CO2 doesn’t cause warming isn’t dishonest? Isn’t a lie? Wouldn’t be perjury in a court of law?
If you have any doubt as to whether or not this is being done, go read the post linked to by HB above.
Thomas Huxley // April 16, 2008 at 6:42 pm |
Can we be really sure Aleo understood the implications ? :-)
.
P. Lewis // April 16, 2008 at 6:51 pm |
Leif
You appear to be guilty of not reading Tamino’s piece closely enough.
You wrote:
Of course he wouldn’t be! Plotting the data doesn’t make one guilty of perjury, and your quoted point is saying something Tamino never actually claimed.
What Tamino actually wrote was:
It’s the swearing of something as true under oath when it is known to be false that would be perjury.
——————-
PS to all. My CET 2008 should, of course, have read 2007 … oops!
David B. Benson // April 16, 2008 at 6:56 pm |
P. Lewis // April 16, 2008 at 4:07 pm — I encourage reporting percieved profession misconduct to whomever in the professional organization is charged with receiving such reports. If it is not obvious who that individual is, then send the report to the president of the professional organization.
Professional ethics are not matters to be lightly discarded.
Leif Svalgaard // April 16, 2008 at 7:20 pm |
All Tamino had to do to show how ridiculous D’Aleo’s graph is was just to plot ALL the data with the scaling chosen by D’Aleo. D’Aleo is his own worst enemy. But, it is not correct to say that D’Aleo creates the *false* impression that CO2 has no effect by his choice of scaling. Choosing Tamino’s scaling does not make things true as there is debate [not with D'Aleo] on what the scaling is. You can say the scaling is this or that, which would then be your contribution to the debate, but this does not close the debate.
[Response: You're not convincing anybody, and you don't flatter yourself by trying so hard. The scaling wasn't even an issue until you made it one. And your earlier statement that "I never claimed that you were dishonest just that you cherry picked" is an insult to our intelligence.]
Leif Svalgaard // April 16, 2008 at 8:03 pm |
HB: “You’re not convincing anybody, and you don’t flatter yourself by trying so hard.”
In these polarized and polarizing blogs, nobody ever convinces anybody of anything. I was just voicing my opinion.
Raven // April 16, 2008 at 8:12 pm |
Good grief.
Question: Would a -1 degC/decade trend over 10 years with no volcanic events demonstrate that the IPCC predictions were wrong?
Answer: Most definately. (if someone disagrees then you are basically saying that the IPCC is peddling unfalsifiable psuedoscience).
Question: Would a flat trend over 10 years with no volcanics events demonstrate that the IPCC predictions were wrong?
Answer: It depends. The IPCC did not clearly state its expectations for weather noise.
Since the IPCC did not clearly state what its expectations were that means that anyone analyzing the trends is free to make reasonable assumptions. That means D’Aleo’s claim that the last 10 years of data contradicts the IPCC claims is perfectly reasonable.
Now others can disagree and make other assumptions about what the IPCC expectations for weather noise were. However, you can’t say D’Aleo misrepresented anything. The data prior to 1998 is irrelevant if one is making the claim that the last 10 years of data is not consistent with the IPCC predictions.
[Response: The data prior to 1998 is NOT irrelevant. And EVEN IF we completely ignore it, the last 10 years of data IS consistent with IPCC projections.]
Mike B // April 16, 2008 at 8:30 pm |
Leif said:
Tamino never even mentions the scaling of the CO2 in the original post, it wasn’t part of his criticism. If Tamino was guilty of anything it’s rescaling the CO2 plot at a more intelligent level and not mentioning it.
Raven // April 16, 2008 at 8:35 pm |
Tamino says:
“And EVEN IF we completely ignore it, the last 10 years of data IS consistent with IPCC projections.”
Only if someone accepts your assumptions about what the IPCC meant. Others have made reasonable and scientifically justifiable assumptions an use those to show the last few years are not consistent with the IPCC projections.
[Response: Baloney. You obviously have no idea of the *probable error* in the trend over the last 10 years.]
Leif Svalgaard // April 16, 2008 at 8:58 pm |
Mike B: “Tamino never even mentions the scaling of the CO2 in the original post, it wasn’t part of his criticism. If Tamino was guilty of anything it’s rescaling the CO2 plot at a more intelligent level and not mentioning it.”
It is about the truth and the whole truth, …
Furthermore, later he said “creating the *false* impression”. The more ‘intelligent’ rescaling is using ‘intelligent’ as in ‘intelligent design’, namely as the meaning that fits your own a priory opinion. Hasn’t enough been said about this already?
[Response: Too much has been said. By you. You're the one who *created* the issue of scaling by accusing me of cherry-picking, which *is* accusing me of dishonesty even though you deny it. Shame on you! And plotting the temperature time series but making the range of the temperature axis ridiculously large *will* create a false impression.
You made a foolish objection, it's been shown over and over again to be wrong, but you're too attached to your ego to let it go.]
dhogaza // April 16, 2008 at 9:24 pm |
Your task, if you choose to pursue it, is to point us to where the IPCC has claimed that the anthropogenic global warming hypothesis has predicted that El Niño and La Niña events would stop prior to 1998 …
Rattus Norvegicus // April 16, 2008 at 9:38 pm |
Raven, you might want to read this post and come back and tell us what you learned.
Leif Svalgaard // April 16, 2008 at 10:28 pm |
HB: It is not about ego at all. And I do not take ‘foolish’, etc as worthy from you [true or not]. All I asked you to do was to tell the whole truth but in a way that was compatible with D’Aleo [what he should have done]. I have simply extended his graph to earlier times [I had data handy back to 1880, so it is not the whole truth, but close enough]. The graph is here http://www.leif.org/research/DAleo.png
I don’t know of a way for me to show an image, so maybe I could ask to to do my the favor and show the figure for me, if at all possible? My graph shows the folly of D’Aleo’s graph from the view point of AGW. Now, I don’t think D’Aleo even thought of this issue. He probably just let the graphing software pick the scaling. And people saying that I was advocating a 12C for 2xCO2 just got this backwards. The D’Aleo scaling implies a much smaller sensitivity as is evident from the graph.
TCO // April 16, 2008 at 10:35 pm |
Tammy:
A. I agree with you on scaling and using all the data.
B. picking at 1975 can cut both ways. Yes it IS a turn of the data. And we see it visually. And can describe it mathematically. But the point is, is it better to show all the data (including pre-1975) to show the “changeability of data) or is there some reason like aerosols to cut at that point. I think givent the issue is in contention itself. debate, it is not best form to cut there. This is a very mild, minor comment.
C. It would be helpful if you could find a case of offense by “your side” on the perjury issue so that we can disaggregate sidedness of the debate with “what is perjury”. This would NOT prevent a further examination that showed the Rethuglicans (like me) more at fault in frequency offence, but would help in definition of the failing itself.
D. My impression is that you have NOT done a detailed thoughtful investigation of what are the legal perjury findings with respect to expert testimony (looking at law articles, posting on Volokh.com, case example research, etc.) but are trying to use the CONNOTATION of the word or the SPECTRE of legal proceedings to score some points against the idiots against the other side.
E. None of the above changes my wanting to take idiots from my side and hold them firmly head under arm and give nuggies to the extent of pain. Then slappity slappity slap.
P. Lewis // April 16, 2008 at 11:18 pm |
David B. Benson said
Yes, of course David. I hope you realise my question was rhetorical on behalf of all, which I grant is not easy to appreciate in a written comment.
Eli Rabett // April 16, 2008 at 11:26 pm |
FWIW pushing the CET back later than 1730 is a risky business, first because a bunch of the measurements were not made in central england as I recall, but are fill ins from the Netherlands and then because some of the instruments and methods were very funky. 1730 is a pretty safe start although later might have been better. The origin of this urban legend is M&M, it was originally raised by them in their endearing clueless way. However, if you RTFR, particularly
Parker, D. E., T. P. Legg, and C. K. Folland, 1992: A new daily Central England Temperature Series, 1772-1991. Int J Climatol, 12, 317-342.
The reason that data before 1730 is chancy is clearly explained in the first paragraph of the 1992 Parker, Legg and Folland paper:
“Manley1953) published a time series of monthly mean temperatures representative of central England for 1698-1952, followed (Manley 1974) by an extended and revised series for 1659-1973. Up to 1814 his data are based mainly on overlapping sequences of observations from a variety of carefully chosen and documented locations. Up to 1722, available instrumental records fail to overlap and Manley needs to use non-instrumental series for Utrecht compiled by Labrijn (1945), in order to mate the monthly central England temperature (CET) series complete. Between 1723 and the 1760s there are no gaps in the composite instrumental record, but the observations generally were taken in unheated rooms rather than with a truly outdoor exposure….”
Which means that the Manley reconstruction is only continuous from 1722 on, but the information upon which it relies from 1723-28 has further difficulties, essentially absolute values were not reliable, and the series was constructed by taking the difference between measurements made by those thermometers and ones thought to be more reliable after 1727, and then repeatedly differenced to get values before 1727.
In the light of this, it is perfectly reasonable to truncate the CET series at 1730.
On balance this illustrates the principal of RTFR and the danger of someone unfamiliar with an area trying to do an “audit”. To use the CET before 1730 would clearly have been a mistake, and I think you could make a good argument that it should have been cut off at 1772.
nanny_govt_sucks // April 16, 2008 at 11:43 pm |
Leif, thanks for the graphic. I was curious how this data would look using D’Aleo’s scaling for CO2. Tamino/HB, wouldn’t CO2 charted as an anomaly, and lined up with the temp anomaly be less controversial?
Leif Svalgaard // April 16, 2008 at 11:49 pm |
Nanny: and both standardized to std-dev = 1 for their common interval.
Leif Svalgaard // April 17, 2008 at 12:04 am |
Nanny, here is the graph with zeroed and normalized T and CO2:
http://www.leif.org/research/DAleo2.png
This is the graph HB could have produced instead of dishing out vitriol.
Leif Svalgaard // April 17, 2008 at 12:16 am |
I forgot to mention (the whole truth thing) that I also removed the annual variation of CO2, since D’Aleo did and since the temperatures are anomalies too.
Alan Woods // April 17, 2008 at 1:00 am |
Tamino, you say “The 1730s weren’t even close to as warm in the CET record as modern times. Must I graph them all?”.
Well, I wasn’t asking *you* to graph them all. But anyway, according to Jones and Briffa (2006). “UNUSUAL CLIMATE IN NORTHWEST EUROPE DURING THE
PERIOD 1730 TO 1745 …”:
“On an annual basis, mean temperatures for the period 1729–1738 are only 0.3 ◦C below the average for the last ten years (1995–2004)”
J&B also say:
“The rapid warming in the CET record from the 1690s to the 1730s and then the extreme cold year of 1740 are examples of the magnitude of natural changes which can potentially be recorded in long series. Consideration of variability in these records from the early 19th century, therefore, may underestimate the range that is possible.”
That is why it is important to plot the record in its entirety.
[Response: I wonder whether their "only 0.3 deg.C below" applies to the CET record -- because I'm looking at the data right now and the difference between the 1729-1738 decade and the 1995-2004 decade is 0.44 deg.C, not 0.3. But we have even more recent data; the difference between the 1729-1738 decade and the 1997-2006 decade is fully 0.59 deg.C, just about *twice* the quoted figure 0.3. A full 0.59 deg.C warmer than the warmest pre-20th century decade you can find fits my description of "weren't even close."
Did you think I hadn't looked at the data?]
L Miller // April 17, 2008 at 1:54 am |
That wasn’t the objection. The objection was that any sensitivity less then 10-12 deg for X2 CO2 would make the temperature plot look flat compared to the CO2. IE it would make it appear as if CO2 were rising sharply with little or no change in temperature. This choice of scale allowed D’Aleo to say “look how big the CO2 change is and yet there is almost no change in temperature” even though the sharpness of the CO2 rise is coming entirely from the choice of scale.
Alan Woods // April 17, 2008 at 2:20 am |
Tamino, I don’t know why you wonder if their analysis refers to the CET record. You think I’m pulling your chain? Read the paper.
[Response: Because the numbers don't match. The paper is behind a paywall.
You think I'm pulling *your* chain? Go look at the data.]
Alan Woods // April 17, 2008 at 3:54 am |
OK Tamino, I realise my post may have been a bit obtuse when refferring to Jones and Briffa, but the quote directly refers to the CET.
Now, I don’t know why Phil Jones and Keith Briffa’s analysis differs to yours, but I think they might be actually looking at annual means within two decades they are comparing, rather then a decadal mean of annual temperatures.
Regardless, I think that my original point (whi I thought was the same as yours) still stands. i.e. that all the data should be included.
I don’t know where you delineate close/not even close when comparing temperatures (is it 0.3, o.45, or 0.6?) but I would have thought that the warmth observed in the 1730’s quite remarkable given the minimal human influences on climate then when compared with today.
[Response: Silly me, actually looking at the data.]
Alan Woods // April 17, 2008 at 4:28 am |
Tamino, don’t be so facetious. If you remember this started because cce linked to a truncated version of CET (for some reason you interpreted it as a call for *you* to include the data). Thus, when I say all data should be included I mean all the data in the CET.
With respect to you “actually looking at the data”, so did I, and so did Phil Jones and Keith Briffa. But, if you’re going to use a non-physical and subective term like “not even close” to describe it then obviously we need to determine what you actually mean by it. Not to mention the fact that you’re ignoring the obvious context of the LIA and minimal human impact on climate at that time.
[Response: You objected to the graph linked to by cce because it left out the "very warm 1730s." I pointed out that the 1730s weren't nearly as warm as modern times. You refer to a paper by Jones & Briffa, giving a quote which clearly implies there's a decade "only" 0.3 deg.C cooler than the most recent decade. I had *already* looked at the data before saying "weren't nearly as warm," and 0.3 deg.C decadal comparison ain't so. Now you say "I think they might..." and "you're ignoring the obvious context of the LIA..." And you're telling *me* not to be facetious?
You want to know what I mean by "not even close"? OK, I'll post that too.]
cce // April 17, 2008 at 5:29 am |
Here is the full CET data with 5 year moving average:
http://cce.890m.com/cet.jpg
The warmest year is 2006, 0.35 degrees warmer than anything in the 1700s.
The warmest 5 year period is 2002 through 2006, 0.562 degrees warmer than anything in the 1700s.
The warmest 10 year period is 1997 through 2006, 0.589 degrees warmer than anything in the 1700s.
Alan Woods // April 17, 2008 at 7:14 am |
I said the warm 1730s, Tamino. I didn’t say ‘very warm’. Warm is a relative term is it not? Relative to the CET record the 1730s were warm. If you don’t think so I suggest you read H.H. Lamb’s “Climate History and the Modern World”.
In the CET record, the 1730s are one of the warmest decades and aren’t really matched until the 1990’s. Considering the LIA was all the rage and there was minimal human impact on climate back then, I find that quite remarkable. Indeed, people at the time found it quite remarkable, which is why they were in for a rude shock when the winter of 1739-40 hit.
Now, why do you have an objection to the CET record being displayed in its entirety?
P. Lewis // April 17, 2008 at 12:37 pm |
Leif and n_g_s
Surely it doesn’t matter at all (much?) whether the CO2 data, when plotted on the same graph as the temperature anomaly data, are plotted as an anomaly or as ppm as long as the ppm scale is chosen appropriately in the first place. Why? Because all you have to do to get from any CO2 anomaly to the actual ppm value is to add back in the actual value of your chosen zero level. The relative positions of the two trends will be identical if the ppm scale was chosen correctly; just the actual numbers will change.
And comparing your last linked graph illustrates this nicely it seems. Surely, Tamino’s plot and yours are essentially indistinguishable if you put back in the actual numbers on your chosen anomaly scale. On that basis alone I’d conclude that Tamino chose the correct scale for plotting CO2 on the temperature plot.
And Leif, in the interests of giving the whole truth, it would be helpful to add in what the anomalies in your plot actually mean, since you obviously don’t mean that the global average temperature has gone up ~5°C since 1910 (which might be a normal first assumption when dealing with Hadley temperature anomaly data).
Boris // April 17, 2008 at 1:43 pm |
“the 1730s are one of the warmest decades”
CET is Central England Temperature, right? So we’re talking about a very small region, correct? And this is supposed to compare to global temperatures how?
Hansen's Bulldog // April 17, 2008 at 2:50 pm |
The discussion of Central England Temperature (CET) was actually spurred by a truly idiotic comment by Raven:
This caused cce to link to a graph (from the Hadley Centre website) of the longest of all temperature records, CET. Then Alan Woods mentioned that the Hadley Centre graph omitted part of the CET record, including the warm 1730s. I replied that the 1730s weren’t even close to as warm in the CET record as modern times. Eli Rabett gave much interesting background on the CET record, pointing out that the Hadley Centre was not being deceptive in omitting part of the CET data because the earlier data were demonstrably less precise, and that there’s plausible reason to argue for cutting off data before 1772. Alan Woods quoted a paper by Jones & Briffa which implies that there’s a decade (very close to the “1730s” ) which is only 0.3 deg.C cooler than the most recent decade (at the time of their publication). I responded that the data contradict that. In addition, data after that publication have made the “most recent decade” even hotter. It’s still not exactly clear what Jones & Briffa were referring to. Finally cce has linked to a plot of the entire CET record. I’ll have more to say about it in an imminent post.
But the whole thing started with Raven’s moronic contribution. CET is not global temperature, “parts of Europe” isn’t either, and those data going back to the 1700s are not “comparable to today.” Raven’s comment was nothing more than an attempt to deflect attention away from the topic of this post: Joe D’Aleo’s blatant cherry-picking (omitting data because they disagree with his claims) and Noel Sheppard’s propagandizing it.
Hank Roberts // April 17, 2008 at 3:19 pm |
Well, yeah. There’s either one very active longterm person or a flock of ‘em using the same userid and approach out there on climate blogs.
Leif Svalgaard // April 17, 2008 at 3:44 pm |
P. Lewis:And Leif, in the interests of giving the whole truth, it would be helpful to add in what the anomalies in your plot actually mean, since you obviously don’t mean that the global average temperature has gone up ~5°C.
No snide comments please. As I clearly explained the data [both T and CO2] have been ‘zeroed’ [mean subtracted], then divided by the standard deviation of the result. In both cases for the same time interval [1958-2008]. So the Y-scale is obviously not °C. The reason my plot looks just like Tammy’s is not physics or ‘appropriate’ scaling. I guess [for his plot] he did a least squares fit to get the scaling factor. This will force the two curves to agree, regardless what the ‘true’ sensitivity’ is.
David B. Benson // April 17, 2008 at 4:50 pm |
Leif Svalgaard // April 17, 2008 at 12:04 am — That is a nicely done, very clear plot. Thank you. Could you do it again using
http://cdiac.ornl.gov/trends/emis/tre_glob.htm
as the basis for the CO2 line?
J // April 17, 2008 at 4:58 pm |
Wow, there’s a lot of discord in this thread. I generally enjoy reading what both Tamino and Leif have to say, and the slightly nasty tones back and forth seem a bit uncalled for.
Tamino, your postings are as always great, but sometimes lately your responses to comments seem to escalate to too angry too fast. Leif, I’ve only seen “Tammy” used by people at (or from) CA who are being deliberately obnoxious, and was surprised to see you adopting that.
You should both go sit in the corner now.
:-)
chopbox // April 17, 2008 at 5:32 pm |
I’ve found this discussion to be interesting for a couple of reasons.
The first was a good demonstration (for ALL OF US) on how to continue with the main point of a discussion instead of rising to unflattering remarks not germane to the main point. For this, thank you, Leif.
To get to the second reason why I found this discussion interesting, we first have to wonder why Tammy made the effort to change the CO2 scaling from his first graph (that showed that he could replicate D’Aleo) to his second. As Leif points out, this change is unnecessary to show Tammy’s point that D’Aleo was cherry-picking. All that was required for that was to extend the time axis. And it’s not to show a physical law: as others have stated, for that, we’d want to see log(CO2). I don’t think Tammy did it because of an objection to the implied sensitivity, because he tells us in one of the replies to Leif that that’s not why he did it. So then why?
I’m scratching my head here and am left with the conclusion that Tammy simply liked the way the CO2 plot lay right along the temperature plot. In short, he preferred that look enough to go to the trouble of drawing up another graph that showed it that way.
Do I think Tammy did this to deceive us? No. “No” again. And just in case you missed it the first two times, “no” once more. But I also think that it wasn’t the best way to present the data. Why? Because it could leave an impression with a casual observer that there is a really good correlation between CO2 and temperature, and Tammy believes (at least I think he does) that that correlation exists between log(CO2) and temperature. Now naturally, if this graph were continued into the past or the future (in both cases we don’t CO2 data, but we can imagine) we would expect this apparent correlation (between CO2 and temperature) to disappear. But what this means is that Tammy is himself cherry-picking as Leif points out. Not intentionally, I believe. But that this occurred in a post devoted to the nefariousness of cherry-picking shows to me how difficult it really is for ALL OF US to resist making the data talk instead of truly listening to it. And that’s the second reason I found this discussion so interesting.
[Response: Once again (from Wikipedia), cherry picking: "the act of pointing at individual cases or data that seem to confirm a particular position, while ignoring a significant portion of related cases or data that may contradict that position."
I picked a scale which illustrates that CO2 levels and temperature have both risen during the time span covered by the data selected by D'Aleo. "Picking" is NOT "cherry picking."
This is almost as frustrating as the reader who said that Al Gore *lied* in an inconvenient truth, but only when pressed for details did he state that by the word "lie" he meant honest mistakes, not intentional deception. I, and several readers, took exception to that. He's not allowed to alter the meaning of the word "lie." You and Leif are not allowed to alter the meaning of the phrase "cherry picking."
And as I've said before, keeping the same relative scale used by D'Aleo would require making the range of the time axis so large as to significantly inhibit the meaningfulness of the graph.
This is the biggest and most annoying non-issue on this thread.]
Raven // April 17, 2008 at 5:53 pm |
The source I was looking at is here:
http://home.casema.nl/errenwijlens/co2/europe.htm
This data is incorporated into GISS. The reference for that claim is here: http://data.giss.nasa.gov/gistemp/sources/gistemp.html
This data makes it clear that the warming trend would be much less significant if data prior to 1800 was incorporated into the graph. That makes a graph starting in 1900 as “deceptive” as a graph starting in 1998.
The point of this example was to demonstrate the rediculous nature of Tamino’s claim that he is not cherry picking because he includes ‘all the data’. He includes ‘all the data’ from selected datasets. The fact that those datasets start at a certain point in time does not make the trends any less deceptive.
If you want to determine whether someone is misrepresenting the data you must look at the claim being made. In D’Aleo’s case he is claiming that warming stopped in the last 10 years. That is evident from the data. He does not claim that warming did not occur prior to that point. If anything, he is implicitly accepting the temperature rise until 1998 as a fact.
You would have a point if D’Alea was claiming that the temperatures did not rise over the last 100 years.
[Response: You are so wrong, in so many ways, about so many things, that I'll do a whole post about it. Stay tuned.]
Jürgen Hubert // April 17, 2008 at 6:09 pm |
In case you are interested, I have analyzed a similar case of cherry-picking to generate a cooling trend:
http://jhubert.livejournal.com/181274.html
Leif Svalgaard // April 17, 2008 at 6:35 pm |
Benson: The data is the yearly emissions. I take it that you want them summed somehow and maybe added to a base value. Explain at bit more what you think make sense.
HB: the whole truth [from the same wikipedia article]: When a person is assigned to advocate a particular position, then cherry picking might be seen as entirely appropriate. Defense lawyers and prosecutors on both sides of a criminal case are one such example: each side tries to emphasise evidence that supports their position, while minimising the impact of contrary evidence. It is often assumed to be the responsibility of the opposing counsel to present any contrary data.
And I certainly think you consider you a self-appointed advocate of a particular position, and as such can justify cherry picking. It just isn’t my style and perhaps I reacted too strongly, projecting my own ethics onto others, which may not be appropriate, so for that I sincerely apologize.
Dano // April 17, 2008 at 7:13 pm |
Tamino, your postings are as always great, but sometimes lately your responses to comments seem to escalate to too angry too fast.
IMCE, this is a natural human reaction to dealing with denialists and FUD purveyors for any period of time. It’s a no-win, because once engaged, denialists get grumpy when you ignore their ramblings, claiming “refuse to discuss” or “censorship” or “refusing to look at facts” or some rhetorical cr*p, made up at the moment.
Keep up the good work, Tamino, and be yourself. It’s your house. If the shrieking chimp squad doesn’t like it, well, buh-bye! Buh-bye now!
Best,
D
fred // April 17, 2008 at 7:21 pm |
We return after a couple of days lost to deadlines to another most depressing thread filled with intemperate abuse and that most unpleasant behaviour, righteous indignation, when a few simple statements of fact would have fixed the error at once.
And you complain about CA!
The technique used here will be very familiar to Europeans with a certain background. We first make an association of ideas between the advocacy of a counter revolutionary position, and some crime which is not being committed. In this case we compare Comrade D’Aleo’s error to that of a perjurer, though Comrade D’Aleo is nowhere near a witness stand nor under oath, so his error has nothing to do with perjury. We then, having established the heinous nature of his offence by association, hint at sanctions to come, by intimating that it is almost as bad as, has many of the elements of, if done in a different context would be. This is straightforward bullying, we have heard all this too, those of us with memories. It would normally be preparatory to giving him a good scare, and coercing his associates or employer into bring pressure to bear on him.
The next step is to mount an interpretive attack on the individual. Here we seek to allege that this is not a simple mistake. The mistake is so obvious that only the worst kind of ideological blindness could have led him into it, and such a blindness must be deeply rooted in anti Party tendencies, probably due to atavistic leanings because of his class origins. Or perhaps a false identification with class origins other than his own, which would be even worse. Or whatever. It is all jargon anyway. In your case it is the jargon of right wing denialism and probable belief in creationism….
Pretty soon we will be pointing out that he must be sick to behave in this manner, and be in need of heavy tranquilization to help him adjust to and become a worthwhile member of society.
You think you are different, you think this all has nothing to do with you. What I am telling you is that the technique is the same.
It is not possible that a cause defended in these terms is a good one. You do not mean to produce this conclusion, but it is what you are doing. A cause defended like this, a cause in need of defence like this, must be wrong. Must be.
[Response: I'm sick of your pretentious self-righteous posing. Your whole theme seems to be that we have to give equal consideration to every argument from both sides, no matter how stupid or deceptive, and if we're the least bit disrespectful to outright liars or total morons then global warming must be false. Are you really that gullible? That stupid? Or are you the world's most pernicious denialist?
The "holier-than-thou" attitude which has been the hallmark of your comments is nothing but astounding, offensive arrogance. You're a total fake, and this comment shows just how hypocritical is your protest against "intemperate abuse." Get over yourself. ]
chopbox // April 17, 2008 at 8:20 pm |
Tamino said “… And as I’ve said before, keeping the same relative scale used by D’Aleo would require making the range of the time axis so large as to significantly inhibit the meaningfulness of the graph.”
Oh, I don’t want you to keep the same RELATIVE scale. Relative? No.
All I want is for you to extend the time axis on your first graph as far back as you want (as you’ve done on your second graph) and to keep the same temperature scale (as you do) and CO2 scale (as you don’t) as your first graph. In fact, the only thing that I am objecting to (and that, only because I read Leif and realized he was correct about this) is that you change the CO2 scale. If you keep it the same, there will be no problem placing the data on the graph, but the CO2 plot will fall more steeply than the temperature plot so that the CO2 plot won’t lie over the temperature plot along its whole (short) history.
For me to understand why this was NOT done, I must speculate on your thought processes. Please correct me when I stray too far from the truth. That said, here goes.
D’Aleo’s graph attempts to show that CO2 is NOT related to temperature in the last ten years. You complain, rightly, that D’Aleo’s contention would fall apart if we look at a longer time span than ten years.
You do this. You see, using the same scale that D’Aleo uses, that the CO2 falls more steeply than temperature and that a casual observer is not going to understand that there is a deep connection between CO2 and temperature. You realize that the correct thing to do would be to look at log(CO2), but also realize that all you need to do to make this relationship apparent to the casual observer is to alter the CO2 scale. If you choose the scale cleverly, it will lie right over the temperature plot and the casual observer will say “Yup, that D’Aleo is certainly wrong: there is a connection.”
But of course, this is wrong! The true connection is not between CO2 and temperature (even though that relationship looks good on your graph) but between log(CO2) and temperature. The spurious connection you have shown will only work at short time scales (which is of course the same problem with D’Aleo).
D’Aleo deliberately used only a portion of the data at hand. You deliberately chose a CO2 scale that gave a good first glance. D’Aleo’s is cherry-picking. You say yours is picking. Whatever. The point is that BOTH of these manipulate (or massage, or blah, blah, blah … ) data to show, not the whole truth, but an untruth dressed up as a truth and that BOTH of these could be shown to be spurious if only we could see more data. In D’Aleo’s case, getting more data is easy; in yours, we’d have to wait for more data to become available. The real difference between the two approaches is that you COULD do it correctly and show a truth you’re comfortable with, and D’Aleo could not.
Since I am not D’Aleo and I am not you, I can’t be sure about D’Aleo’s motives and I can’t be sure about yours. But I am willing to believe that you are a scientist first and a rhetorician second (or somewhere way down the line) so I think you did it this way because for a brief period you zoned out, or because the way you did do it has the advantage of being quick. That said, it’s still wrong, and I think you should just say “Yup, little screwup there. Here’s the right way.” and then do it.
[Response: If I did as you suggest, and kept the same CO2 scale as the first graph, then the CO2 data when extended back in time goes *off the scale*. At the start of Mauna Loa measurements, the CO2 level is about 315 ppmv, but the scale on the original graph only goes down to 355, so a large fraction of the data would disappear below the bottom of the "window."]
David B. Benson // April 17, 2008 at 8:45 pm |
Leif Svalgaard // April 17, 2008 at 6:35 pm — I would like to see the CO2 concentrations for the entire interval from 1850 AD superimposed on the temperature data. I beleive that will make a better graphic (than the very good one you produced.)
In 1850 AD CO2 concentration was 288 ppmv. Starting there one can sum up (a fraction of) the yearly additions in such a way to fit the beginning portion of the Keeling curve, at about 315 ppmv. That should be approximately correct.
Thank you. :-)
dhogaza // April 17, 2008 at 9:03 pm |
You complain about our host being rude, and do so by equating him to Stalin (who perfected this device in a very short time after Lenin’s death, and used it to banish his rivals, and later to justify their murder).
Your attitude may be “holier than thou”, but if your words were addressed to me, I’d be deeply insulted, and, if we were Europeans of a certain background attending the University of Heidelberg, it would be swords in the fighting room …
Take a look in the mirror and take a good look at the face of hypocricy.
David B. Benson // April 17, 2008 at 9:41 pm |
Teapot tempest.
This is a low bandwidth communication medium and often leads to various sorts of misunderstandings. Tamino’s main posts in each thread are always very well written, clear and understandable. I’m impressed that he finds the time to do that, monitor the comments, do his day job and still is able to take his wife out to breakfast now and again! :-)
chopbox // April 17, 2008 at 9:50 pm |
Thanks, Tamino, for your response.
That CO2 drops below 355 is a problem for keeping the exact same axis. What’s a good solution? One way would be to extend the axis, but then we’d still have a graph that doesn’t really hint at the true relationship (since CO2 would be rising much more quickly than temp).
The more I think about this, the more I think the correct way is to go straight away to a graph that does show the physical law that D’Aleo is trying to refute. That means a two-stage solution. First, you transfer D’Aleo’s graph to one that shows log(CO2) instead of CO2 and second, you extend it back in time. D’Aleo doesn’t need to do this because he’s trying to hide the relationship but someone trying to refute D’Aleo probably needs to show the true relationship.
In any case, do you now agree that picking a CO2 scale that shows a spurious relationship between CO2 and temp is not the right way to show that D’Aleo is wrong?
[Response: D'Aleo's purpose was to imply that while CO2 is rising, temperature is not. He does this by showing a tiny fraction of the available data, cherry-picked so that it starts with a huge el Nino and ends with a la Nina. My purpose was to show that if you look at *exactly the same data* he chose, but plot all of it, he's contradicted. Transforming to ln(CO2) wouldn't be exactly the same data he used.
But for another purpose -- exploring the relationship between CO2 forcing and temperature -- then yes, ln(CO2) is the right variable to use.
If I had done so, I'll bet denialists would show up in droves to accuse me of applying a "deceptive" transformation.]
steven mosher // April 17, 2008 at 10:29 pm |
First off, they cherry picked the hell out of this.
So, no excuses for them.
I think it’s interesting to use the perjury metaphor Tamino.
Essentially, you frame the debate in a criminal context, turning your opponents into criminals. I think you’ve used this language before. Now, I cannot complain about rhetorical excess. But your suggestion of prosecution is actually not so much of a metaphor, as some have suggested actual prosecution of people who deny an accepted scientific theory.
This type of rhetoric is not aimed at changing coolists minds.
It’s real target is warmists. And what you tell warmists is that we can or should treat these people like criminals. Like it or not that is what this language DOES.
It’s similiar to the denialist trope,
and the creationist slur. Students of rhetoric will understand the force of demonizing tropes.
When people who use these types of metaphors get power, then bad things can happen.
These tropes are effective at
mobilizing the warmists and inflaming the coolists. And the more you inflame the coolists, the more irrational they appear, then the more likely it is for warmists to accept some kind of final solution to the debate. This is just an observation about how language has been used in the past and how that use changes people and their behavior.
Like I said, I don’t have any real issue with this kind of rhetorical device. It’s easy enough to take apart. So you say perjury;they yell fraud. You say consensus;they say expelled. you say denier;they say alarmist. It’s not dialogue, it’s diatribe.
Again, I’m not complaining about your rhetorical device. I’m just pointing out what this type of language has lead to historically. So, If your purpose is to inflame the other side, demonize them, and play to the master warmists, then you did a good job.
Their chart was stupid and misleading.
[Response: For the record: I don't advocate, or support, criminal prosecution of those who deny the reality of global warming.
D'Aleo's graph/Sheppard's post is not a crime. It's a sin. As for "it's not dialogue" -- you give them too much credit. Dialogue with them is impossible.]
JCH // April 17, 2008 at 11:24 pm |
Perjury is an interesting crime. Though commonplace, it’s seldom prosecuted. Don’t believe me, spend a day at divorce court.
Raven // April 18, 2008 at 12:18 am |
Tamino says:
“For the record: I don’t advocate, or support, criminal prosecution of those who deny the reality of global warming.”
Yet in the next sentance you resort to the rhetoric of religion and call them “sinners”. Does that mean excommunication is in order?
Your problem is you have taken what is a reasonable scientific hypothesis and elevated to the level of unassailable truth.
Unfortunately, climate science is a field where controlled real life experiments are impossible and this means nothing in climate science can ever be considered to be the ‘unassailable truth’
You yourself admitted as much in your post called “You Bet” where you set out what would have to happen to demonstrate that major conclusions of the IPCC were wrong.
FWIW – I agree that 10 years of data is not enough to falsify the consensus, however, it is enough to increase the uncertainty because we don’t know where the temperatures will actually go in the next 5-10 years. If they stay stable or drop then the consensus will be falsified – even by criteria that you set out.
If the actual temperatures do go that way then 1998-2002 will become another change point in the time series – just like 1974-76. If that happens then the D’Aleo analysis will be considered accurate and yours will be considered junk. If the temps go the other way then you will be vindicated.
In either case, we have to wait 5-10 years to see who has a better handle on what is happening with the climate.
EliRabett // April 18, 2008 at 12:34 am |
What is the current best value for climate sensitivity (oC/Watt) for TSI before or after dividing by four??
dhogaza // April 18, 2008 at 12:43 am |
He’s done no such thing. Pointing out that someone who disagrees with the scientific consensus is an outright liar does NOT elevate the hypothesis to the level of “unassailable truth”.
What baloney.
And, no, it won’t. The so-called analysis is crap, regardless.
Raven // April 18, 2008 at 12:44 am |
Tamino,
FWIW, sometimes you say things that I do agree with. For example, in your last post on D’Aleo you pointed out that ENSO is a measure of sea surface temperature which means correlation with land temperatures is no surprise and not interesting. It was an excellent point and I point it out to other skeptics when it comes up on other forums.
[Response: And I owe you an apology. I thought your claims about European temperatures were your own creation; now that you've linked to your source I see where you got 'em. The stuff there has serious problems and I intend to show why in considerable detail. But I understand that you were only relaying what you got from another source.]
trrll // April 18, 2008 at 1:04 am |
I don’t agree that the idea of “sin” is necessarily religious. I think that most scientists would agree omitting the part of a dataset that does not favor one’s argument is a sin against fundamental scientific principles of honesty and integrity.
It appears to me that some people are trying to distract from this severe infraction of scientific ethics by elevating a minor question regarding the most informative way of presenting a complete datase–the appropriate scaling of the CO2 trace–to the same level as data omission. Certainly, if Tamino had attempted to draw some conclusions from the similarity of slope, when the actual slope is somewhat arbitrary, such an accusation might have (slight) validity, but I see no evidence of this.
Alan Woods // April 18, 2008 at 1:20 am |
Boris, others
1. I wasn’t making any claim about global temperatures. I was saying that the record should be shown in its entirety because the truncated version can have the effect of underestimating the natural variation possible.
2. The warmth of the 1730s is also recorded in other long temperature series, namely the Uppsala and De Bilt temperature records. According to Phil Jones and Keith Briffa , the 1730s was the warmest decade in each of these records (ie CET, De Bilt, Uppsala) until the 1990s occurred.
Leif Svalgaard // April 18, 2008 at 2:31 am |
Benson: the analysis you asked for is here: http://www.leif.org/research/DAleo.pdf
Hope this is what you wanted.
Raven // April 18, 2008 at 2:33 am |
Tamino,
Here is a chart that illustrates my point about error bars: http://strangeweather.files.wordpress.com/2008/02/brohan_uncertainty1.jpg
As you can see the visual impression of the trends is quite different when one includes the error bars. The errors bars in this chart certainty support my assertion that we really don’t know what the global temperature was in 1900 to a 1/10th of a degree.
Now there are situations where error bars are not really necessary to make a point but if you are going to castigate someone else for “deceptive” use of data then you really cannot leave out the error bars on your own charts (BTW – I know D’Aleo did not use error bars either – this is a “people in glass houses should not throw stones” thing).
[Response: This is an example of how people can be misled, or can mislead themselves. There's a VERY SERIOUS ERROR in those graphs. It states explicitly that the 95% error ranges for all factors are *added*. This is an erroneous statistical procedure. In order to combine independent errors one should take the square root of the sum of the squares, which is considerably smaller than the sum. If the errors are not independent, then the total probable error due to all sources is likely to be much smaller even than this. The graphs you link to definitely inflate the total probable error.
Here's what HadCRU says about the accuracy of their estimates:
The graph you link to implies a 2-sigma of about +/- 0.15 recently and about +/- 0.6 in the 1850s -- three times what HadCRU says.
And whatever the error range for individual data values, the error range for *trends* is much smaller. I'll say with confidence that the trend since 1975 according to HadCRU is 0.018 +/- 0.004 per year (2-sigma), but I would never claim that any given data point is accurate to 0.004 deg.C.
Error bars are always useful and sometimes crucial, but *wrong* error bars are worse than none.]
Raven // April 18, 2008 at 3:13 am |
Tamino,
The graph is form this paper:
http://www.agu.org/pubs/crossref/2006/2005JD006548.shtml
which includes Phil Jones himself on the list of authors. The link i provided is from Julien Emile-Geay’s blog. I assume both sources are considered credible by you.
[Response: I consider them credible but not infallible. You can't just add the 95% error ranges from independent errors to get the "total" 95% error range. And the numbers I quoted in my last response come directly from the HadCRU data site -- also a credible source.]
Raven // April 18, 2008 at 3:28 am |
Tamino says:
“I consider them credible but not infallible. You can’t just add the 95% error ranges from independent errors to get the “total” 95% error range.”
Then I look forward to a blog post that debunks P. Brohan et. al. 2006 with the same zeal that you show when skeptics make “VERY SERIOUS ERRORS”.
[Response: Don't get snotty. If Brohan et al. have made a serious error, I'll get to the bottom of it and it'll appear on this blog. If I'm in error about this, I'll own up to it. But a snide implication that either case would be in the same league with D'Aleo is wrong.]
trrll // April 18, 2008 at 4:12 am |
Actually, my “visual impression” of these graphs is essentially the same my visual impression of Tamino’s graph presented earlier. I don’t know if Tamino is right in suspecting that they actually added the errors arithmetically rather than using the correct “hypotenuse” calculation. My completely nonrigorous “eyeball” test says maybe they did it right. Perhaps they did not intend that level of mathematical literalism when they say it “adds” the error. If you have access to the paper (your link is not free), perhaps you can provide the actual equation from the methods.
Also, I’d be interested in knowing whether these are represented as error limits of the individual points or error limits for the smoothed trend. The latter would of course be much smaller.
In any case, it seem striking that the lower limit of land temperatures is now above the peak upper limit for the entire earlier part of the graph. That seems to also be what the authors found striking. From their abstract
Hank Roberts // April 18, 2008 at 4:33 am |
Whoah, two things.
Who says someone actually does claim to know
> … what the global temperature
> was in 1900 to a 1/10th of a degree.
Someone actually claims to know that? Who? Where? On what basis?
That’s certainly not what the ‘best estimate’ means on that chart.
So, first bait trolled, scent in the water.
Then to the trickery. The chart is presented. The text on the picture uses a word that a mathematician will interpret to mean a mathematical operation. A graphics person will interpret it as a layering operation. And a grammarian will interpret it as needing a better description.
And I think DB bit on this trolled piece of bait there.
“Added” — but not mathematically.
“Added” — as a graphic layer!
There is NO way that the “blue” or “red” or “green” error range gets narrower back at 1850.
This isn’t like a stacked graph showing all the contributions to atmospheric CO2, stacked up from zero.
Each of these colors represents an uncertainty around a best estimate line. Starting in each case from the line.
They are layered, graphically.
Each color is a _graphic_layer_ that is “added” to the picture and you’ll probably find that explained in the text of the article. I’m guessing of course.
You only see the parts of the underlying bands that stick out past the bands on top.
All the bands get wider as you go back in time. Uncertainty is like that.
I am just being logical here.
Savage me, please.
Let’s not play “get the bulldog and the authors to fight” til we know what is meant by the words on the image — get the text of the paper.
Hansen's Bulldog // April 18, 2008 at 6:45 am |
I obtained a copy of Brohan et al. 2006, and I’ve discovered what the graph means. Hank Roberts is right, that the graph was meant to show how big the component parts are, not what their combined effect is. The reason for doing so, and that the authors are fully aware of what they’re doing, is made clear when they discuss combining errors for individual grid boxes:
The phrase “adding in quadrature” means to take the square root of the sum of the squares. So I was quite right about how individual error components should be combined. I was quite mistaken to believe that the graph was ever meant to imply that the summed terms represent the net uncertainty.
But what else was I to think? Raven, you simply pointed to a graph with incredibly large colored regions surrounding the best estimate, and commented that “As you can see the visual impression of the trends is quite different when one includes the error bars.” Those incredibly large colored regions don’t represent the error bars, they’re the separate components of them. And you didn’t mention the source of the graph, so we could investigate in detail, until I raised the issue. Your unambiguous implication that those were the “error bars” is wrong. Too bad you didn’t bother to find out.
I also have to wonder: why did you point to a graph for land-only, oceans-only, and their difference, without bothering to direct attention to a similar graph from the same paper for the globe? I’ve put it in UPDATE #2 to this post. EVEN IF we take the graphed colored regions as the “error bars,” it still belies the claim that “the visual impression of the trends is quite different.”
Now I’ll indulge in a bit of a rant.
This happens all the time. Someone points to a graph or paper or data which is either absurd, or quite correct but taken out of context (or with no context at all) and described in a way which is just plain wrong.
And I’m rather peeved that I’ve been assailed with criticism for changing the scale for CO2 used by D’Aleo, when NOT doing so would require either flattening the temperature curve almost beyond recognition or letting the CO2 data fall off the bottom of the graph. Then there’s the not-so-subtle implication that I “should” have plotted the logarithm of CO2 — when it’s obvious that the whole point of this post is to show, using D’Aleo’s own choices for data sets, what the difference is when you don’t leave out almost all of it, including the most important part. And frankly, the accusation of “cherry picking” is infuriating, especially from those who don’t seem to know what the hell it means. The further accusation of “cherry picking” for not graphing older European temperature records, or paleoclimate reconstructions, or the Vostok ice core data, or Michael Jordan’s career shooting percentage, is so idiotic that the limitation of foul language prevents me from saying much more.
I realize I’m the one who chose to blog about this. I ain’t gonna quit. But it sure gets tiresome dealing with a constant barrage of stupidity.
Hank Roberts // April 18, 2008 at 7:41 am |
‘Raven’ does a lot of throwing the same kind of dust in people’s eyes,
One very busy trickster.
Look at the page from which this ‘Raven’ linked just the image out of context:
http://strangeweather.wordpress.com/
Here’s what that blogger posted the picture for, excerpt follows:
——————————————
“… try going back 100 years and the measurement error and sampling bias become so large you’ll be lucky to have an accuracy of 0.5 C. And that is during a period broadly known in the field as “instrumental”, that is to say the one over which we have a reasonable number of physical measurements of temperature. As you can see on the following graph from Brohan et al, 2006, this uncertainty grows back in time rather quickly already.”
————————
But that took some digging since Raven carefully took the picture out of context and misdirected our attention by pointing to an abstract instead of the blog he lifted it from.
Raven’s a troll. Successful, too, this time. He got your goat there boss. One more for his collection.
The better the bridge you build, the more traffic you get, the bigger and more persistent the trolls are who come to tax the readers.
Hank Roberts // April 18, 2008 at 7:55 am |
Oh, and my, oh, my the familiar names you’ll find _around_ that explanation I quoted for that picture, on that blog.
Read the comments
http://strangeweather.wordpress.com/2008/02/17/the-heisenberg-principle-of-climatology/#comments
Raven got that image from a thread about McI’s recent visit to Georgia Tech. Funny.
Boris // April 18, 2008 at 8:26 am |
Alan,
If you show the CET record then you are showing regional variation. I don’t see why it is important to show regional variation when we graph global temps. The other records you mention are both in Northern Europe.
Alan Woods // April 18, 2008 at 10:26 am |
The accusation of “cherry picking” for not graphing older European temperature records was never levelled at you. You simply decided to take umbrage at the suggestion that the CET should be shown in its entirety. But thanks for the heads up – I didn’t realise that Phil Jones was being ’stupid’ when he argued that the full record of the CET should be considered.
[Response: I know that *you* didn't accuse me of cherry-picking. It was Raven. His 1st comment on this thread: "In your case, you cherry picked a start point that makes the rise look as dramatic as possible." His 2nd comment: "You did not plot all of the available data. We have temperature data going back to the 1700s in parts of Europe ... various sorts of proxy data going 1000s of years... Call it what ver you want but it is still cherry picking to make the point that you wish make."
Hank Roberts is right. Raven is a troll.]
OzDoc // April 18, 2008 at 11:17 am |
Hansen’s Bulldog … Well said!!
Hang in there, it really is worth the effort.
non27 // April 18, 2008 at 11:48 am |
Brohan et al. 2006 is freely available from CRU:
http://www.cru.uea.ac.uk/cru/data/temperature/HadCRUT3_accepted.pdf
steven mosher // April 18, 2008 at 1:05 pm |
Tamino, I’m not saying you advocate imprisoning them. I’m saying that the rhetoric of criminality or the rhetoric of immortality (sins) can lead to an unfortunate situation. so whether you imprison them or damn them to hell, the point is this.
As you believe dialogue is impossible, then what?
when a country decides that dialogue with Iran is impossible, then what?
that’s my point. when one decides that words don’t do the job, well one chooses other tools. As that day comes, it’s best not to have the opponents of the change you seek characterized as criminals or sinners. If they are so chracterized, then you get gulags and witch burnings.
Alan Woods // April 18, 2008 at 1:06 pm |
OK I’m laughing now, I wasn’t paying any attention to Raven initially. I’d suggest if you want to avoid the trolls then lay off the value-laden terms like “sinners”
J // April 18, 2008 at 1:41 pm |
I’d say that the primary lesson of this thread is the (frequent) insufficiency of naive visual interpretation as a method for understanding the relationship between variables in complex systems.
There is a reason why people use statistical methods for data analysis, and there’s also a reason why both D’Aleo and Anthony Watts rely so heavily on simple, qualitative, visual presentations.
Visualization may be helpful in understanding the relationships among data sets, but it is more of an art than a science.
Hank Roberts // April 18, 2008 at 2:23 pm |
J // 2008 at 1:41 pm
Yes!
dhogaza // April 18, 2008 at 2:48 pm |
So, let’s see if I understand …
If someone commits a crime, we shouldn’t label them “criminals”, because doing so leads to prisons?
If someone’s caught lying, we shouldn’t call them liars, because doing so might hurt their feelings, and if we hurt their feelings they won’t quit lying?
While if we’re nice to them and ignore the fact that they’re lying, this positive feedback will encourage them to stop lying?
steven mosher // April 18, 2008 at 3:00 pm |
Brohan on Measurement error.
“The random error
in a single thermometer reading is about
0.2C ( 1 sig) [Folland et al., 2001]; the monthly
average will be based on at least two readings a
day throughout the month, giving 60 or more
values contributing to the mean. So the error
in the monthly average will be at most
0.2/SQRT(60 )= 0.03C and this will be uncorrelated
with the value for any other station or
the value for any other month.”
So. here is the question. For most stations the Observer ( human) goes to the min/max thermometer and records 2 numbers once a day.
1. The Min temp recorded since the last observation.
2. The max temp recored since the last observation.
For all of these observations the observer is told to round the measurement to the nearest degree. No rounding rules for .5F or .5C are provided. Do they round up? do they round down? But, nevermind. They have a MIN measurement which is rounded, and a MAX measurement that is rounded.
So what is the daily measurement? Is the daily measurement what the thermometer said. a measurement for mean and a measurement for max? Or what the observer transmitted to NCDC
Min and MAx are reported to NCDC. The Min and max are added together and divided by two
and the result of that is rounded. So Now, how many observations do I have for a day? 1 observation of Mean? or two observations?
So. Open question. If my instrument records two measurements over a 24 period, and if my standard error for each measurement is .2C.
and if I round those two measurements, then add them. Then divide by 2, then round again.
How many measurements do I have for the month? 60? or 30?
Tamino, can you provide some insight on this. I’m confused.
[Response: I'm not sure that HadCRU is basing their analysis on the already-averaged daily mean; then may be doing it based on the daily max and min reported temperatures. In that case there are 60 per month (for a 30-day month). I do notice that's what my local national-weather-service climatology reports do. If you first average the daily max and min, but *don't* round the result of that, then you still have 60 (effectively). If you average the daily max and min, then *do* round, then effectively you only have 30.
But the rounding to the nearest degree may apply only to the U.S. where we're using the Fahrenheit scale. The Celsius people might be reporting more digits, certainly the Europeans are. I notice that data from the European Climate Assessment & Dataset Network gives *daily* values to 0.1 deg.C. In this case the resolution (0.1 deg.C) is smaller than the sigma, and the rounding has practically no effect on monthly averages.
So my best guess is: it really is 60 per month.]
drawp // April 18, 2008 at 3:46 pm |
Re: Tom Woods 4/16
Tamino said “..the data don’t say..”
Woods: “Tamino, your grammar is terrible..shouldn’t that be “.. the data doesn’t say…”
WRONG “data is plural,so “don’t” is correct.
” the singular is datum”
I remember back to a more literate time when, on the way to the ballpark, the arrow on the highway said “STADIA” not STADIUMS:
Barney Frank // April 18, 2008 at 4:35 pm |
“If Sheppard’s post or D’Aleo’s graph were sworn testimony in a court of law, I’d charge them with perjury.”
vs.
“For the record: I don’t advocate, or support, criminal prosecution of those who deny the reality of global warming.”
Kind of hard to reconcile both statements. Upon reading the former I took it to be a straightforward accusation of prosecutable and intentional dishonesty were it stated under oath.
If it was merely hyperbole then why not knock it off?
I might best be described as somewhat of a skeptic, because the science seems rather unsettled, but have no particular dog in the fight and am willing to follow the science wherever it leads.
Repeated hostile imputations of “idiotic” and “very disingenuous”, especialy by the host of the blog, may elicit cheers from the choir, but tends to turn genuinely curious folks like me away from the door. But maybe the cheers are the point?
[Response: Not even ONE WORD about D'Aleo's graph? Do you think it's "intelligent" and "honest"?
I say it's deceptive, and deception is the only reason people like you think "the science seems rather unsettled." THAT is "the point."]
trrll // April 18, 2008 at 4:48 pm |
Here’s a harder question: Why do you care?
Is anybody really interested in the absolute mean temperature anywhere? The discussion is about the change in temperature. So it doesn’t really matter whether they use the min, the max, the mean. It doesn’t matter whether they round up or down. It doesn’t even matter whether everybody does it the same way or not. It doesn’t even matter if they arbitrarily multiply by two. The only thing that matters is that each measuring station is reasonably consistent–in fact, even that isn’t all that important, so long as the procedures haven’t changed in some nonrandom way that is correlated among many stations.
So I have to wonder about motivations when people start nitipicking the details measurement methodology in this way. Is there really some point to this, or is it just to create an impression of doubt?
[Response: Just my opinion: it didn't strike me as nitpicking to stir up doubt, just curiosity.]
steven mosher // April 18, 2008 at 4:55 pm |
Ok Thanks Tamino.
David B. Benson // April 18, 2008 at 5:45 pm |
Leif Svalgaard // April 18, 2008 at 2:31 am — Thank you! :-) That is quite through.
L Miller // April 18, 2008 at 7:01 pm |
http://www.amazon.com/How-Lie-Statistics-Darrell-Huff/dp/0393310728
More psychology then statistics but it’s still one of the most worthwhile reads around. It deals with how statistics can be distorted by their presentation and it’s even more relevant now then when it was written because of the ease with which anyone can make a chart in Excell and throw up statistics on a web site.
Barney Frank // April 18, 2008 at 7:05 pm |
I made no comment on his graph because I’ve seen misleading and incomplete graphs, studies and conclusions from both sides repeatedly.
I understand what your point is; no need to capitalize it.
I am making a seperate one that SHOUTING at people who question the wisdom of calling people idiots and liars and calling people idiots and liars in the first place undermines your credibilty.
BTW your ‘idiotic’ and ‘very disingenuous’ comments were not directed at D’Aleo’s graph, as you seem to imply, but at commentors here.
[Response: You say you've seen misleading stuff from both sides repeatedly? That certainly implies that the level of deceptiveness is comparable for both "sides." I say you couldn't be more wrong. Either you're making it up because you're a troll, or you honestly believe it because you've been duped. If you're not a troll, you fell for denialist sophistry hook, line, and sinker.
Once again: that's "the point." Obviously you didn't get it when you implied that maybe "the point" was getting cheers from my own supporters.
You're entitled to choose your own criteria to evaluate credibility. So am I. It seems to me that idiots and liars should be called by their right names, and being so undermines *their* credibility.]
george // April 18, 2008 at 11:26 pm |
Leif said:
First, according to the IPCC and others (eg, Schwartz) CO2 has accounted for a fairly constant proportion (about 60%) of the total greenhouse gas forcing over the last few decades (up until just recently), so the rise of CO2 (forcing) when scaled (by 1.6), pretty much tells you the story of what has happened to total greenhouse gas forcing overall over that time period.
Furthermore (again according to IPCC), greenhouse gases have been responsible for nearly all the positive radiative forcing over the same period.
Given that — and the fact that temperature change is directly proportional to radiative forcing change — “scaling” CO2 (or more appropriately CO2 forcing) on a graph so that it shows the match with temperature is not at all deceptive.
It shows reality.
According to IPCC, most of the recent warming is due to CO2 and other greenhouse gases.
That is certainly not something HB simply made up or “cherry picked”.
Hansen's Bulldog // April 19, 2008 at 12:43 am |
Leif Svalgaard: You continue to accuse me of cherry picking. You’re wrong, your behavior is unethical, and you owe me an apology. Your latest, and every subsequent comment you make, which includes this reprehensible behavior goes to the trash pile.
Leif Svalgaard // April 19, 2008 at 1:14 am |
I thought I did already back in:
April 17, 2008 at 6:35 pm
HB: the whole truth [from the same wikipedia article]: When a person is assigned to advocate a particular position, then cherry picking might be seen as entirely appropriate. Defense lawyers and prosecutors on both sides of a criminal case are one such example: each side tries to emphasise evidence that supports their position, while minimising the impact of contrary evidence. It is often assumed to be the responsibility of the opposing counsel to present any contrary data.
And I certainly think you consider you a self-appointed advocate of a particular position, and as such can justify cherry picking. It just isn’t my style and perhaps I reacted too strongly, projecting my own ethics onto others, which may not be appropriate, so for that I sincerely apologize.
[Response: I am indeed a self-appointed advocate of a particular position. But I did *not* minimize the impact of contrary evidence. The whole point of this post is to show the difference between plotting *all* the data (which I did) and cherry-picking only that since 1998 (which D'Aleo did).
My choice of scale for the CO2 axis, which seems to be the root of your claim, was done to avoid either flattening the temperature curve or allowing the CO2 data to fall off the bottom of the graph. I've made this abundantly clear more than once. It certainly doesn't "minimize the impact of contrary evidence."
Cherry-picking may be appropriate for lawyers but it's not for scientists. I find the accusation offensive. Yes you apologized, but then you *repeated* it. Multiple times. Quit it.]
Leif Svalgaard // April 19, 2008 at 1:44 am |
HB: The temperature curve in the D’Aleo interval is already flat [that was his point I think], before that there is a slight rise from ~1975 to ~2000, that I don’t think D’Aleo would disagree with. This is clearly seen on the plot I showed earlier:
http://www.leif.org/research/DAleo.png
And the CO2 curve does not fall off the bottom, since you are in control of where the bottom is.
If I *repeat* my offense, I can *repeat* my apology, as well. If you think being accused of [excusable] cherry-picking is so bad, how do you think D’Aleo must feel about being accused of perjury?
Gavin's Pussycat // April 19, 2008 at 2:24 am |
While I do agree that people should never be prosecuted for what they say, they should be held accountable for the consequences of their lies.
Like shouting ‘fire!’ in a packed theatre is not protected speech, when intentional misrepresentation predictably leads to loss of life, speech becomes murder and should be prosecuted as such.
Not that I have any illusion about that ever happening in a world where Nixon and Pinochet died free men, and Kissinger is still at large.
…and about HB ‘cherry picking’, no he did not. What he did is commonly, and properly, referred to as ‘rubbing it in’ :-)
dhogaza // April 19, 2008 at 2:32 am |
No, that’s not his point. His point is to “prove” that there’s no significant correlation between increased atmospheric CO2 and temperature.
Not just that there’s no correlation in his chosen interval, but that the lack of correlation during that interval “proves” that increased atmospheric CO2 has little or no effect on temperature at all. Ever. Over all of time.
dhogaza // April 19, 2008 at 2:35 am |
Well, when he’s claiming that his cherry-picked 10-year interval proves that CO2 doesn’t cause warming, he’s either lying or patently stupid. He claims to be smart, so there’s only one choice left.
Hank Roberts // April 19, 2008 at 2:49 am |
Well, he’s not being accused of perjury, because he didn’t swear in court that what he wrote is true.
Notice the parallel in US Congressional hearings — some witnesses are sworn, and can be held in contempt of Congress if they don’t tell the truth; others are there by design because they will be presenting points of view that the Congresspeople want on record, and question them to lead them through getting it on record, and thank them for — without having them swear to the truth of their comments.
Ahem Inhofe Ahem.
steven mosher // April 19, 2008 at 12:49 pm |
“The warmth of 1998 was too large and pervasive to be fully accounted for by the recent El Nino. Despite cooling in the first half of 1999, we suggest that the mean global temperature, averaged over 2-3 years, has moved to a higher level, analogous to the increase that occurred in the late 1970s.”
2-3 years is a short peroid dont you think?
steven mosher // April 19, 2008 at 12:54 pm |
trrll.
I’m not nit picking. the measurement error is inconsequential however you figure it, using 30 or 60. I was just curious about tamino’s take on it.
Brian Schmidt // April 20, 2008 at 4:12 am |
A pseudo-trackback:
Maybe not perjury, but a beautiful tool for our case
“….I doubt it’s misleading enough to be perjury, but I’d welcome any idiot opponent who actually used it in a climate change case. I’d rather win the case than convict the opposing side’s expert for perjury, and you could use the first graph to support the truth….All this is a long-winded way of saying that if the other side uses a piece-of-garbage data to support their opinion, we can use the importance they attach to it by saying whoever has the best data on this issue wins, and then show our hand.”
http://backseatdriving.blogspot.com/2008/04/maybe-not-perjury-but-beautiful-tool.html
Hank Roberts // April 20, 2008 at 6:02 pm |
I thought Cough Inhofe Cough was bad about how they only required that hostile witnesses swear to tell the truth while letting their friends put their beliefs on the record without being under oath.
But this beats all, speaking of trying to find cites for claims made to Congress:
http://scienceblogs.com/denialism/2008/04/congress_isnt_priceless.php
Tony Edwards // April 21, 2008 at 10:23 pm |
Having slogged my way through the above, several things come to mind. First is the low level of courtesy used, but that seems to be par for the course. Second is the first graph posted by Tamino. Maybe I’m being too observant, but the slope of the section from about 1905 to 1945 looks to be about the same as the section from 1970 to 2000, if anything slightly steeper. And yet the CO2 line, if mentally projected back from it’s starting point in 1958 would have been flattening out, which, if there was a causation, would have produced a much flatter temperature anomaly curve. And, although seriously noisy, the 1860 to about 1890 has a similar slope to the other two. So how do we know that whatever caused the earlier rises does not have at least some effect in more recent times? And, if there is total causation, why are there two significant cooling trends, (or three, if you count the current near standstill)?
David B. Benson // April 21, 2008 at 11:34 pm |
Tony Edwards // April 21, 2008 at 10:23 pm — Possible reasons include changes in aerosols, including black carbon, i.e., “soot”. Also, the PDO appears to modulate between
strong El Nino/weak La Nina
and
weak El Nino/strong La Nina.
The climate varies on decadal scales and so the oscillations you mention might best be considerd ‘random’. I’ll post more about this on the ‘Open Thread’ in a day or two. Patience.
dhogaza // April 22, 2008 at 12:09 am |
I think you meant to say “if CO2 were the sole cause”, rather than “if there was a causation”, a statement that no climate scientist would agree with, making it a strawman (hopefully an unintentional one).
CO2 is a forcing, but it’s not the only forcing.
Rather than having a bunch of people contribute to your education here, why not do some reading? You can start with the primers at Real Climage …
Greg // April 22, 2008 at 5:44 am |
It is important to show the whole truth. What do you think of truncating Briffa in the TAR then?
null{} // April 22, 2008 at 12:45 pm |
steven mosher // April 19, 2008 at 12:49 pm said
“2-3 years is a short period dont you think?”
Good catch steven. If I recall correctly, on this very blog and several others, we were recently lectured by Certified Climatologists that somewhere between 17 and 30 years is necessary .
I think maybe that Peer-Reviewed Paper should be now rejected by those same Certified Climatologists.
dhogaza // April 22, 2008 at 5:31 pm |
Well, did he go further than to say “we suggest”?
Did he say it’s DEFINITIVE? Did he attempt to “prove” it statistically?
Or did the paper say just what it appears to say, i.e. offer an OPINION.
No one would smack down Lucia, for instance, for stating that her OPINION is that the recent record disproves IPPC projections.
She’s being smacked down for falsely claiming her bogus statistical treatment PROVES it with 95% confidence.
Surely even folks like null{} and mosher see the difference?
Many do.
Hank Roberts // April 22, 2008 at 5:41 pm |
You don’t reject a paper based on picking a sentence fragment out of the abstract.
And El Nino is a discrete event with a known duration.
Sheesh, guys. Cite your sources, will you?
Eschew obfuscation. Comments can be misread as clever if people don’t have a link to read for themselves what you’re leaving out.
http://pubs.giss.nasa.gov/abstracts/1999/Hansen_etal.html
Phil. // April 22, 2008 at 5:46 pm |
null{} said:
““2-3 years is a short period dont you think?”
Good catch steven. If I recall correctly, on this very blog and several others, we were recently lectured by Certified Climatologists that somewhere between 17 and 30 years is necessary .”
The ‘2-3 years’ referred to is the averaging timescale not the time required to falsify a prediction!
David B. Benson // April 22, 2008 at 7:33 pm |
Tamino, aka “Hansen’s Bulldog” — Would you be so good as the give me the numbers for the temperature anomalies in
http://tamino.files.wordpress.com/2008/04/10yave.jpg
so that I don’t have to guestimate them? Thank you in advance.
TCO // April 22, 2008 at 10:37 pm |
I had a sarcastic comment “worst thread evah” that Tammy shot down. He seems to have a feel for my evil tendancies to introduce silliness. So I will add some thought to make him approve the post.
Basically, what i think is that there is interesting exploration of ideas and actual analysis that goes on. Often in the head post. But also sometimes people like Lazar. I actually try to supply some at times with Socratic questioning, although I have been told that this is very annoying and justifies hemlock forced drinking. But, the other thing that goes on, much, much more…is just sort of the nattering bnack and forth. it’s entertaining. Enjoyable. And for some…is all they are capable of. But then we have the S/N issue.
So what does that boil down to? Well…that having a topic about “perjury” is much more accessible and enjoyable for hoi polloi of either side than to actually find out how much standard deviation dividing changes the PC1 HS index.
Capisce?
Allowed?
David B. Benson // April 23, 2008 at 12:55 am |
As this is about an analysis of temperature ‘anomalies’ and Tony Edwards aksed about these on this thread, it seems appropriate to continue here.
I used the GISP2 analysis of dates and temperatures by Alley, just for the Holocene from 10300 years before present (ybp) to 100 ybp, i.e., 1850 CE. (‘Present” is defined to be 1950 CE.) I divided the entire 3.740 K temperature variation in Central Greenland over this period into 19 bins to determine the frequency with which the temperature at one interval stayed in the same bin or transited to another at the next interval.
For 10 year intervals, the temperature typically stays in the same bin (60% or so), transits to a higher bin about 20% of the time and a lower bin about the same. Occasionally the transitions are two bins higher or lower, but these are rare.
There are some rather dramatic runs: the runup in temperature for the first 250–300 years; the crash and rapid recovery around 8200 ybp due to volcano eruptions, most notibly the super-eruption (VEI 7) of Kuril Lake; the runup near the climatic optimum.
Despite this, the 10 year transistions are remarkably dull. So I next removed the PDO, etc., oscillations by looking only at the 50 year transitions and then also the 60 year transitions. This better shows the dramatically large temperature changes.
We can compare these to the 50 and 60 year transitions in
http://tamino.files.wordpress.com/2008/04/10yave.jpg
by, for 50 years, considering only the differences from 1850 to 1900, from 1900 to 1950, etc., and for
60 years, from 1820 (we use the 1850 data) to 1880, 1880 to 1940, and 1940 to 2000. In both analyses, it is the last transition which seems to be of current interest.
It is easy to use the GISP2 data to produce the bins on the 10 year average HadCRUTv3 graph, once one knows how to adjust from Central Greenland temperature differences to the HadCRUTv3 temperature anomalies. Using the 8200 ybp event and the estimated tropical temperature drop of 3 K at that time, I have chosen a ratio of 1:2, that is 0.2 K in Central Greenland becomes 0.4 K in HadCRUTv3. This is part of the whole procedure which is mostly likely to be in some error.
But assuming this, draw the bins (this is not arbitrary, the GISP2 data includes 1850 CE) as
bin04 -0.6 to -0.2
bin05 -0.2 to +0.2
bin06 +0.2 to +0.6
to observe that for both the 50 year and 60 year transitions. the transitions from one interval to the next are
bin04 -> bin04
bin04 -> bin05
bin05 -> bin06
to check that at no time in the entire Holocene has there every previously been a transition from bin04 to bin05! But no matter, consider the frequency for the transition from bin05 to bin06, the one of interest:
for the 50-year data, this occured 12% of the time the climate was in bin05; for the 60-year data, this occured 17% of the time the temperature was in bin05.
Based on this frequentist probabilty argument, there is anyway a less than 1 chance in 5 that the climate has, in the past, made such a transition.
For some of the rapid climate changes in the record, the cause is clear. Most notible is the 8200 ybp event. For the current improbable change, the cause certainly appears to be changes in forcings caused by human activities; on this scale of 50 or 60 years, the climate is best not considered to be ‘random’.
Since I used the data, I need to inlcude the citation:
Alley, R.B.. 2004.
GISP2 Ice Core Temperature and Accumulation Data.
IGBP PAGES/World Data Center for Paleoclimatology
Data Contribution Series #2004-013.
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.
J // April 23, 2008 at 12:03 pm |
David:
No guestimation is really necessary. You can go to the Hadley website (http://www.cru.uea.ac.uk/cru/data/temperature/#datdow) download the Hadcrut3v GL file, ignore everything except the first and last columns (years and annual means, respectively). Calculate the mean for each decade, and, if you want to match Tamino’s graph as closely as possible, plot the decadal means against the midpoint of the decade (i.e., 1855 for the 1850s, 1865 for the 1860s, etc.)
Visually, my graph seems identical to his, except possibly for the last point (the current decade), for which his point seems almost imperceptibly higher (I could be imagining this). Anyway, here are my numbers:
1855 -0.378
1865 -0.370
1875 -0.283
1885 -0.302
1895 -0.385
1905 -0.443
1915 -0.431
1925 -0.300
1935 -0.129
1945 -0.068
1955 -0.162
1965 -0.116
1975 -0.088
1985 0.081
1995 0.238
2004 0.397
steven mosher // April 23, 2008 at 1:12 pm |
dhog, lucia isnt being smacked down. She’s sharing her data, explaining her methods, reporting the results, taking suggestions, modifying her position as she learns new things. It’ s instructive to watch the dialogue. like her i expect the warming to resume to the levels seen before.
her an atmoz are now looking at some interesting
things in the satillite records. Tamino should have a look
dhogaza // April 23, 2008 at 5:04 pm |
Her *insistence* that she’s shown with 95% probability that the IPCC is full of crap, her *insistence* that she’s blown a professional statistician specializing in time-series analysis (HB) out of the water, etc, is not the attitude of a learner.
I’ve not bothered reading her blog in weeks, her lack of humbleness in those posts I’ve read (there and in other places), and her inability to understand simple, basic things (i.e. the IPCC projections aren’t meant to be interpreted as annual predictions in the way she uses them), makes it worthless.
Hank Roberts // April 23, 2008 at 5:39 pm |
DB, sanity check please — do you agree that Null, and Mosher
null{} // April 22, 2008 at 12:45 pm
mosher // April 19, 2008 at 12:49 pm
are mistaken about the 2-3 year period?
Hank Roberts // April 23, 2008 at 5:40 pm |
Er, that’s addressed to HB, not DB.
(all bulldogs look alike to me)
David B. Benson // April 23, 2008 at 6:08 pm |
J // April 23, 2008 at 12:03 pm — Thank you very much!
I am rethinking my conversion from Central Greenland temperature differences to HadCRTv3 temperature anomalies. The reason is that the total variation for Central Greenland in the Holocene is 3.740 K, but the global temperature change from LGM to Holocene Climatic Optimum is currently thought to be only about 6 K. So I’ll need a better conversion factor, I now believe.
steven mosher // April 23, 2008 at 9:04 pm |
Dhog,
The IPCC clearly says this. Starting from 2001 the
warming we can expect to see will be .2C per decade for the next 2 decades, regardless of emissions. After 2011 the SRES , the particular scenario path we are on, will impact this but I believe all sceanrios are .2C decade or higher.
Now, were I editing this document I would say
this instead. ” we expect warming between 2001 and 2011 to be consistent with the warming since 1975, that is .17C per decade +- 3sig estimate.
In the short term the average of GCM average slightly higher than this figure..
And there would be no problem.
basically, for the short term ( 10 years) just use a naive extrapolation of the past, and for years 11 and out use the GCM forecast.
They screwed up. AGW is still true, fix the problem move on.
The ISSUE is people on the warmist side cant admit a simple mistake. Like Al gore using face footage in his movie. Admit it, own up. move on.
David B. Benson // April 23, 2008 at 10:37 pm |
Central Greenland GISP2 temperature differences
are HadCRUTv3 temperature anomalies, one for one,
based on:
(1) The temperature droped precipitously by
3.048–3.052 K going into the 8.2 kya event.
This agrees with the 3 K drop in tropic sea
surface temperatures at that time:
http://en.wikipedia.org/wiki/8.2_kiloyear_event
(2) The temperature reconstruction for the
Holocene in
http://en.wikipedia.org/wiki/Image:Holocene_Temperature_Variations.png
simily averages the GISP2 data with the other
temperature proxies used, stating this is similar
to other, published reconstruction methods.
With this, and using the 10-year averages provided
by poster ‘J’, we have the following for the
60 year transitions from temperature bin to
temperature bin since 1820 CE (using the 1855 CE
average for 1820 CE) [The bin size of 0.190 K
is computer selected, but is about the recent
decadal change in global temperature.]
date anom. 0.190 bin
—- —— ———
1855 -0.378 04.48
1865 -0.370 04.52
1875 -0.283 04.98
1885 -0.302 04.88
1895 -0.385 04.44
1905 -0.443 04.13
1915 -0.431 04.20
1925 -0.300 04.89
1935 -0.129 05.79
1945 -0.068 06.11
1955 -0.162 05.61
1965 -0.116 05.86
1975 -0.088 06.00
1985 0.081 06.89
1995 0.238 07.722004 0.397 08.56
http://www.cru.uea.ac.uk/cru/data/temperature/#datdow
1825 to 1885: bin04 -> bin04 25%
1885 to 1945: bin04 -> bin06 38%
1945 to 2004: bin06 -> bin08 08%
with the percentages being the percentage of the cases
in the Holocene record from 10.3 kya to 0.1 kya
in which, when the temperature was in the stated bin,
it made the given transition.
dhogaza // April 23, 2008 at 10:42 pm |
Do they say regardless of ENSO?
Do they say regardless of aerosols from a large volcanic eruption?
Do they say regardless of a comet impact on earth?
Or are they talking about forcing and feedbacks due to CO2?
dhogaza // April 23, 2008 at 10:55 pm |
What you’re really, saying, is that the IPCC needs to guard against any statement that might be misread when pried loose from context, because by god if they do so, folks like you are going to quote mine and intentionally misrepresent the IPCC position, so you can jump up and down and say “look, they’re wrong! they’re wrong”.
I suppose that’s true, they should do their best to guard against intentional misrepresentations of this sort, though it’s pretty much impossible to do, as anyone who’s followed the creationist camp’s quote mining of biologists knows all too well.
In your mind, it’s their fault, and we should admit their mistake, and move on.
So, in the spirit of conciliation I offer you this:
The IPCC was wrong to write a sentence that was sloppily worded in such a way that the likes of lucia and you could intentionally use it to misrepresent the scientific claims of the report.
They are wrong to expect the likes of lucia and you to respect context, figures, additional detail, and the underlying message rather than write as though people will digest their report in total.
Because people in the denialsphere are going to quote-mine it to death, there’s no doubt. and will defend that quote-mining endlessly.
Timothy Chase // April 24, 2008 at 3:10 am |
Steven Mosher wrote:
Ahem, …
Please see:
george // April 24, 2008 at 1:41 pm |
Steven Mosher said:
I see you are still peddling the same BS.
You made a similar claim in a previous thread and I pointed out the error back then:
I will give you the benefit of the doubt and make the assumption that you missed my earlier correction to your claim (and are hence not just being dishonest) and that you simply never read what the IPCC actually said.
So, when are your going to actually read the IPCC report — and stop repeating the nonsense?
David B. Benson // April 25, 2008 at 10:03 pm |
I have redone the 60-year interval temperature changes in Central Greenland from the GISP2 data, as previously cited. The program first determines the 10-year averages from 10300 ypb to 100 ypb (1850 CE). Divided into 19 bins, the bin size is 0.196 K. Each decade is placed in the appropriate bin and compared to the bin six decades hence. This gives the following distribution of changes of bin over the six decade intervals:
-6 002 0.002
-5 008 0.008
-4 025 0.025
-3 055 0.054
-2 120 0.118
-1 183 0.180
00 218 0.215
01 205 0.202
02 114 0.112
03 053 0.052
04 018 0.018
05 009 0.009
06 003 0.003
07 002 0.002
approximately normal.
The temperature for 100 kpb is comapred to the HadCRUTv3 temperature anomaly for 1850 CE to convert the GISP2 temperatures differences to the HadCRUTv3 temperature anomalies [under the assumption that Central Greenland temperature differences are equal to the HadCRUTv3 global temperature anomalies]. This prodcedure gives that the temperature changes from the 1940s to the 2000s is from bin06 to bin08.
Such changes occur in the GISP2 data as
up 2 bins:
from ~1050 to ~990
from ~1060 to ~1000
from ~1070 to ~1010
from ~1730 to ~1670
from ~3870 to ~3810
from ~4370 to ~4310
from ~4380 to ~4320
from ~6250 to ~6190
from ~7140 to ~7080
from ~10200 to ~10140
from ~10210 to ~10150
from ~10220 to ~10160
with the ~ to remind us that the dats are in units of ypb. None are particularly striking, but the continued warming from ~10220 to ~10140 is surely due to the orbital forcing induced recovery from LGM.
In the record for changes from bin06 to bin09 [Holocene median temperature bin] are
up 3 bins:
from ~1040 to ~980
from ~1710 to ~1650
from ~1720 to ~1660
from ~3840 to ~3780
from ~8140 to ~8080
The oldest of these changes is due to the recovery of the temperature from the 8.2 kypb event.
The largest up-transition from bin06 is
up 4 bins:
from ~5350 to ~5290
for which I know of no explanation. Any ideas?
David B. Benson // April 25, 2008 at 10:39 pm |
It is instructive to consider longer intervals. I choose 14 decades as surely long enough to remove the effects of various (known) ocean oscillations. The most remarkable facts are:
maximum length up-run = 43 from ~8310.00 to ~7750.00 up 3.00 K
Max up in one interval = 1.97 K from ~8200.00 to ~8060.00
where the first does not mean that the temperature necessarily went up from one decade to the next for 43 decades, but rather for 43 sequential decades the temperature 14 decades hence was higher at the later time. Note that the total variation of decade average temperature over the entire Holocene (as defined) is but 3.724 K in the GISP2 data.
Comparing, as before, to the HadCRUTv3 data, but now from the 1860s to 2000s, the transition is from bin04 to bin08. In the data there is
up 4 bins:
from ~1130 to ~990
from ~1140 to ~1000
from ~4450 to ~4310
from ~4460 to ~4320
from ~4470 to ~4330
which means, for example, that from ~4470 to ~4450 the temperature remained in bin04 with a rather dramatic up-transition of about 4×0.196 = 0.784 K 14 decades hence.
Rattus Norvegicus // April 26, 2008 at 2:44 am |
DB, you are making a fundamental error in your analysis — GISP2 represents a regional rather than a global anomaly.
This is the same problem that the people who insist that there was a MWP: It appears that areas around the North Atlantic experienced an era where there was a salutary warming which allowed increased economic activity, there is also some evidence that there were warm periods throughout the NH, but that they were not global, nor were they synchronous.
In fact, if you look at the events which occured in North and Central America during that period the MWP was anything but salutary: The collapse of the Maya empire and the disappearence of the Anasazi, both due to prolonged drought happened during the MWP.
David B. Benson // April 26, 2008 at 6:15 pm |
Rattus Norvegicus // April 26, 2008 at 2:44 am — I went through that bit in earlier posts on this thread. However, thanks for bringing it up again, becasue the first two points are worth repeating and the third is something I was going to post about in any case.
(1) The GISP2 record for the 8.2 kya event shows 3.0+ K of cooling. Read
http://en.wikipedia.org/wiki/8.2_kiloyear_event
regarding the drop of tropical sea surface temperatures at that time.
(2) The estimation of the global temperature done for
http://en.wikipedia.org/wiki/Image:Holocene_Temperature_Variations.png
appears to just average the GISP2 temperature differences wiht the other data sets, without further adjustment (other than taking longer averages than I have).
(3) CRU states that the global temperature change (HadCRUTv3 global) was 0.6 +- 0.2 K over the last century. My analysis is within those error bars at 0.784 K.
By the way, I can’t find the direct CRU quote again, but did locate
http://climatex.org/articles/climate-change-info/climate-change/
which states it.
If I were going to do more with this, the hazard you mention is certainly apparent. But from the standpoint of observing that similar sized temperature excursions have previously occured during the Holocene, I believe I am on acceptably firm grounds.
With regard to the so-called MWP: Parts of North America and essentially all of Mesoamerica during that period of time was indeed quite dry. I believe it was also warm. What you have observed about the past is what regional forecasters are predicting for the future of those same regions, Mexico and north through Kansas, up to about 40 degrees north latitude, and perhaps eastwards to Springfield, Illinois, etc.
And by the way, this region was desert and semi-desert during the Holocene Climatic Optimum, with tempratures even higher still.
In some respects, the past does predict (aspects of) the future.
David B. Benson // April 26, 2008 at 6:47 pm |
Here is the quotation I wanted: “Over both the last 140 years and 100 years, the best estimate is that the global average surface temperature has increased by 0.6 ± 0.2°C.” From
http://www.grida.no/CLIMATE/IPCC_TAR/wg1/005.htm
My analysis agrres with this for both intervals, being about 0.588 K for the periods ending in the 1990s decade and 0.784 K for the periods ending in the 200s (almost) decade. So for the periods used in the TAR, I am very close to the central estimate.
Dave Andrews // April 27, 2008 at 8:30 pm |
Dhogaza, April 23 5.04pm
“IPCC projections … are not predictions”
Then, Trenberth says they are “what if” scenarios.
So exactly what are they, do the IPCC make clear what they are to the policy makers and the media and why if the science is so settled can they not be more definitive?
dhogaza // April 27, 2008 at 9:09 pm |
There are easy answers to this question. Why don’t you think about them yourself? Maybe you’ll learn something as a result.
Hank Roberts // April 27, 2008 at 10:13 pm |
Dave, Google is often helpful when you don’t know the definition of a word. The IPCC provides them. I found this by putting into the Google searchbox
define:scenario
It’s the third hit on the search result page.
A plausible description of how the future may develop, based on a coherent and internally consistent set of assumptions about key relationships and driving forces (eg, rate of technology changes, prices). Note that scenarios are neither predictions nor forecasts.
http://www.gcrio.org/ipcc/techrepI/appendixe.html
Dave Andrews // April 28, 2008 at 8:41 pm |
Thanks Hank,
I was, however, being somewhat cynical rather than literal.
Julien Emile-Geay // May 1, 2008 at 10:19 pm |
Re : Raven // April 18, 2008 at 3:13 am
Hello everyone,
I would like to make a mea culpa for neglecting to appropriately describe the error bar from the Brohan et al figure so readily hailed by the esteemed Raven as definite proof that anthropogenic global warming does not exist.
This perception is, needless to say, wildly mistaken.
Tamino (as often) is right on both counts :
1) Neither Phil Jones or myself are infallible (esp me).
2) The correct measure of the error is the Euclidean norm of the error vector, i.e. the square root of the sum of the squared errors, not the sum itself.
Ah, what’s in a graph !
I apologize for failing to adequately emphasize this point, as it has unfortunately led to misinterpretations. Mea culpa. Mea maxima culpa.
That being said, it leaves open the debate of how errors should be graphically represented. I do agree with Raven that a curve is often meaningless without an error bar – while it can be equally misleading ot plot the “wrong” error bar.
When I picked the wisdom of errorbar guru Carl Wunsch’s on the topic, he said that the best way to convey error bars is explicitly describe them next to the graph. Sorry for failing in that quest, I’ll try to avoid that in the future.
But regardless, there is no doubt that Sheppard is full of what makes the grass go green. ;-)
TCO // May 1, 2008 at 11:03 pm |
JEG: please hang out here more and please tell us more about over-long and poorly prepared lectures by McI. As well as frisbee sessions on Peidmont park.
Raven // May 2, 2008 at 7:37 am |
Thank you Julien,
“I do agree with Raven that a curve is often meaningless without an error bar – while it can be equally misleading ot plot the “wrong” error bar.”
This was the point I was trying to make. Tamino was going on about how deceptive D’Aleo was and I was trying to show that leaving the error bars off the data is another form of deception.
I just grabbed the graph from your blog because it was the first one that I found.
Julien Emile-Geay // May 2, 2008 at 2:07 pm |
TCO, fortunately there are much more interesting things in life than to bash Steve McIntyre. Such as playing frisbee in Piedmont Park.
Raven, i think we both made a similar mistake : grabbing a figure from the web without thoroughly understanding what it meant. A lesson to be learned…
steven mosher // May 2, 2008 at 5:15 pm |
AR4 tim, not tar.
about .2c decade from 2001 to 2011. From 2011
onward its from .21C and up. Go read AR4.
be that it may a warming of .15C per decade is probably also in doubout from 2001 to 2011.
Beyond 2011, however, things will get back on track.
AGW is true, dont worry. IPCC made a minor boo boo. Fix it, move on. Dont worry be happy
dhogaza // May 2, 2008 at 6:51 pm |
Yes, they made a statement that can, by twisted logic only practiced by those interested in deceipt, be led to claims that “IPCC projections for the 21st century have been disproven by one La Niña”.
Keep putting lipstick on that pig, Mosher.
dhogaza // May 2, 2008 at 6:53 pm |
deceit (to forestall spelling flames)
steven mosher // May 3, 2008 at 1:05 pm |
sorry dhog, I dont their claims for the 21st century have been proven wrong. I think, that
they choose their words poorly WRT the trends
for the first two decades. That’s all, the lukewarmer position.
dhogaza // May 3, 2008 at 2:54 pm |
Yes, they choose their words poorly. Because they’re scientists, and they’re not used to having to write every word of a report in a style that absolutely minimizes the possibility that deceitful types will twist and bend and misuse them. They naively imagine, I guess, that people will read with the goal of understanding the scientific position, not looking for possibilities to lie about it.
A moral question is whether or not they SHOULD have to guard against blatant dishonesty on the part of those interested in preserving the status quo regardless of the scientific evidence.
I’d say, no, they shouldn’t. You obviously believe the opposite, that it’s *their* fault for not having made it impossible for people to lie about the meaning attached to projections.
Just as it was Stephen Jay Gould’s “fault” that, within his copious output as a writer, creationists found snippets they could quote-mine out of context to “prove” that he “didn’t believe in evolution”.
Something which pissed him off until the day he died, but which in your moral framework, is apparently his fault, not of those who twist his words in order to lie about his beliefs.
That about sums it up, I think.
dhogaza // May 3, 2008 at 3:50 pm |
IPCC AR4 WG1, Chapter 10, page 762.
The problem isn’t poor wording on the part of the IPCC. The “problem” is that they didn’t repeat this wording in the caption for each graph, in each sentence that mentions the word “trend”, etc.
Allowing folks like Mosher to pretend that nothing was said about smoothing out short-term variability by pointing out those instances where they didn’t – as though the clear statement above doesn’t exist.
Quote mining …
Hank Roberts // May 3, 2008 at 4:28 pm |
Perhaps time to ask this be added to the list of standard, refuted skepticalscience points — get a number assigned and end the long repetitive posts alternating between this belief and the cites?
The persistent posting of misinformation is no way a ‘lukewarmer’ position, though it’s used to try to convince people to believe that position. Any belief needs to be based on facts people can look up.
El Niño // May 7, 2008 at 4:13 pm |
dhogaza, you rock. Thank you for your spirited and insightful word jousts.
steven mosher // May 7, 2008 at 7:05 pm |
Dhog,
“Yes, they choose their words poorly. Because they’re scientists, and they’re not used to having to write every word of a report in a style that absolutely minimizes the possibility thatdeceitful types will twist and bend and misuse them. ”
The issue is clarity. They imply that the trend from 2001 to 2011 will be .2C for that decade and for decades thereafter will be .21C or higher depending on the SRES. Nobody forced this sloppiness on them. In fact, I have said elsewhere that they just should have remained silent on the matter of the next 10 years and said the truth. The climate over a ten year period is too variable to give meaningful or skillful predictions . Lucia is not being deceitful. She believes in AGW as do I. The IPCC can make mistakes. The sooner people realize that and fix the issues, the better.
You continue:
“They naively imagine, I guess, that people will read with the goal of understanding the scientific position, not looking for possibilities to lie about it.”
Well, I don’t think you could call anything lucia ever wrote was a lie. That she knew one thing to be the case, and actually said another. But, whatever. You dont like her work. Visit her blog,
look at her recent posting on a paper by Foster, Annan et al. and her review of other papers that address Schwartz’s paper, and her criticism of his paper. I wouldn’t call the lady a liar. She’s a diligent thoughful person, I think Judith Curry would agree to that as well, and she is quite sharp and willing to consider other points of view. Consider her exchanges with JohnV and me WRT to the solar issue in this matter. So, I wouldn’t use the lie word with respect to her.
If you’d like JohnVs perspective on Lucia, ask him. I think he’d say she is tough, fair and open. I dunno
go ask him.
Anyway, check out her blog today. There isn’t much flaming, heck even Boris and I get along there. She has a nice house. no politics, few rants.
Even I behave myself there. Maybe we could see eye to eye better in a place like that. I know I’ve said some mean things to you. So sorry.
dhogaza // May 7, 2008 at 8:07 pm |
There’s nothing sloppy in the quote I provided.
There’s nothing sloppy about your dishonesty, either.
george // May 8, 2008 at 12:47 am |
Steven Mosher claimed above
In a previous thread, he claimed
Just above Mosher claimed
If you ask me, the real issue here is not sloppiness on the part of the IPCC but the unsubstantiated claims about what the IPCC said vs what they actually said:
From AR4, Section 3