Guest post by Bob Tisdale
My blog post October to December 2011 NODC Ocean Heat Content Anomalies (0-700Meters) Update and Comments was cross posted by at WattsUpWithThat here. (As always, thanks, Anthony.) Starting at the January 27, 2012 at 8:44 am comment by J Bowers, I was informed of a critique of my ARGO-era model-data comparison graph by the Tamino titled Fake Predictions for Fake Skeptics. Oddly, Tamino does not provide a link to my post or the cross post at WattsUpWithThat, nor does Tamino’s post refer to me by name. But I believe it would be safe to say that Tamino was once again commenting on my graph that compares ARGO-era NODC Ocean Heat Content data to the climate model projection from Hansen et al (2005), “Earth’s energy imbalance: Confirmation and implications”. If he wasn’t, then Tamino fooled three persons who provided the initial comments about Tamino’s post on the WUWT thread and the few more who referred to Tamino’s post afterwards. The ARGO-era graph in question is shown again here as Figure 1. Thanks for the opportunity to post it once again up front in this post, Tamino.
Figure 1
Take a few seconds to read Tamino’s post, it’s not very long, and look at the graphs he presented in it.
My graph in Figure 1 is clearly labeled “ARGO-Era Global Ocean Heat Content Model-Data Comparison”. The title block lists the two datasets as NODC/Levitus et al (2009) and Hansen et al (2005) Model Mean Trend. It states that the Model Mean Trend and Observations had been Zeroed At Jan 2003. Last, the title block lists the time period of the monthly data as January 2003 to December 2011.
In other words, my graph in Figure 1 pertains to the ARGO-based OHC data and the GISS model projection starting in 2003. It does not represent the OHC data or the GISS model hindcast for the periods of 1993-2011 or 1955-2011, which are the periods Tamino chose to discuss.
Do any of the graphs in Tamino’s post list the same information in their title blocks? No. Do any of Tamino’s graphs compare the climate model projection from Hansen et al (2005) to the NODC OHC observations? No. Does Tamino refer to Hansen et al (2005) in his post? No. Do any of Tamino’s graphs present the NODC OHC data or the Hansen et al model projection during the ARGO-era, starting in January 2003 and ending in December 2011? No.
In other words, Tamino redirected the discussion from the ARGO-era period of 2003-2011 to other periods starting in 1955 and 1993. ARGO floats were not in use in 1955 and they were still not in use in 1993. He also redirected the discussion from the projection of the GISS model mean to the linear trend of the data itself. Yet Tamino’s followers fail to grasp the obvious differences between his post and my ARGO-era graph.
In my post, I explained quite clearly why I presented the ARGO-era model-data comparison with the data zeroed at 2003. Refer to the discussion under the heading of STANDARD DISCUSSION ABOUT ARGO-ERA MODEL-DATA COMPARISON. Basically, Hansen et al (2005) apparently zeroed their model mean and the NODC OHC data in 1993 to show how well their model matched the OHC data from 1993 to 2003. Hansen et al explained why they excluded the almost 40 years of OHC and hindcast data. The primary reason was their model could not reproduce the hump in the older version of the Levitus et al OHC data. Refer to Figure 2, which is a graph from a 2008 presentation by Gavin Schmidt of GISS. (See page 8 of GISS ModelE: MAP Objectives and Results.) I presented that same graph graph by Gavin in my post GISS OHC Model Trends: One Question Answered, Another Uncovered, which was linked in my OHC update from a few days ago.
Figure 2
I zeroed the data for my graph in 2003, which is the end year of the Hansen et al (2005) graph, to show how poorly the model projection matched the data during the ARGO-era, from 2003 to present. In other words, to show that the ARGO-era OHC data was diverging from the model projection. Hansen et al (2005), as the authors of their paper, chose the year they apparently zeroed the data for one reason; I, as the author of my post, chose another year for another reason. I’m not sure why that’s so hard for Tamino to understand.
And then there’s Tamino’s post, which does not present the same comparison. He did, however, present data the way he wanted to present it. It’s pretty simple when you think about it. We all presented data the way we wanted to present it.
Some of the readers might wonder why Tamino failed to provide a similar ARGO-era comparison in his post. Could it be because he was steering clear of the fact that it doesn’t make any difference where the model projection intersects with the data when the trends are compared for the ARGO-era period of 2003 to 2011? See Figure 3. The trend of the model projection is still 3.5 times higher than the ARGO-era OHC trend. Note that I provided a similar graph to Figure 3 in my first response to his complaints about that ARGO-era OHC model-data comparison. See Figure 8 in my May 13, 2011 post On Tamino’s Post “Favorite Denier Tricks Or How To Hide The Incline”.
Figure 3
Figure 3 shows the ARGO-era OHC data diverging from the model projection. But the visual effect of that divergence is not a clear as it is in Figure 1. I presented the data in Figure 1 so that it provided the clearest picture of what I wanted to show, the divergence. That really should be obvious to anyone who looks at Figure 1.
Some might think Figure 1 is misleading. The reality is, those illustrating data present it so that it provides the best visual expression of the statement they are trying to make. The climate model-based paper Hansen et al (2005) deleted almost 40 years of data and appear to have zeroed their data at 1993 so that they could present their models in the best possible light. Base years are also chosen for other visual effects. The IPCC’s Figure 9.5 from AR4 (presented here as Figure 4) is a prime example. Refer to the IPCC’s discussion of it here.
Figure 4
The Hadley Centre presents their anomalies with the base years of 1961-1990. Why did the IPCC use 1901-1950? The answer is obvious. The earlier years were cooler and using 1901-1950 instead of 1961-1990 shifts the HADCRUT3 data up more than 0.2 deg C. In other words, the early base years make the HADCRUT anomaly data APPEAR warmer. It also brings the first HADCRUT3 data point close to a zero deg C anomaly, and that provides another visual effect: the normalcy of the early data.
Base years for anomalies are the choice of the person or organization presenting the data. Climate modelers choose to present their models in the best light; I do not.
Those familiar with the history of Tamino’s complaints about my posts understand they are simply attempts by him to mislead or misdirect his readers. And sometimes he makes blatantly obvious errors like using the wrong sea surface temperature dataset in a comparison with GISS LOTI data. His post Fake Predictions for Fake Skepticsis just another failed critique to add to the list.
ABOUT: Bob Tisdale – Climate Observations
SOURCE
The NODC OHC data used in this post is available through the KNMI Climate Explorer:
http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere
The Argo data is a huge improvement over previous OHC measurements, in part because Argo samples all the ice free oceans with a comprehensive geographic spread.
Using pre-Argo data to extrapolate a trend when the much better Argo data is available is poor science.
And as for when will the models be disproved, I’d say they are already disproved. The data is noisy argument doesn’t apply to OHC compared to atmospheric temperatures, because the main source of ‘noise’ in the atmospheric temperatures is variable heat release from the oceans.
If atmospheric temperatures AND OHC are well below model projections as they have been for the last decade then we can be sure the climate is warming at a much slower rate than the models predict, bar the ‘missing heat’ actually existing in the deep oceans (very unlikely IMO).
Alan Statham says:
“Sure, I’ll submit an article. What do you want it to be on?”
I’ll suggest two, so you have a choice:
1. Going strictly by the scientific method, using only verifiable, testable data [no model “evidence”], prove that AGW is anything more than a conjecture in the scientific meaning of the term.
2. Again, rigorously adhering to the scientific method, falsify the following hypothesis if you can:
At current and projected concentrations, CO2 is harmless, and a net benefit to the biosphere.
With regard to base-lines, one of arch-skeptic Richard Lindzen’s best-known and earliest articles is his 1991 Bulletin of the American Meteorological Society article “Some Coolness Concerning Global Warming.”
Lindzen’s baseline temperatures are (1) for northern and southern hemisphere station data the 1950-1970 means (Lindzen Fig. 2), and (2) for ocean data the 1881-1987 means (Lindzen Fig. 4). With this precedent having been established by Lindzen, who is perhaps the most prominent skeptic, these are the baselines that other skeptics should use.
One practical result is that 21 years of subsequent data now show a pronounced “hockey stick” with regard to all of Lindzen’s 1991 measures. And conversely, moving the baseline to later years (like 2003?) does amount to a skeptical strategy of “hide the incline.”
Therefore, it seems to me that Tamino’s criticism is correct in its main point: for skeptical science to be properly evaluated, skeptical scientists should use Lindzen’s base temperatures, even though in doing so, the “hockey stick” of AGW shows itself plainly, relative to the data in Lindzen’s 1991 analysis.
In his blog, Tamino said “Note that there’s a decided hot fluctuation in 2003. So we’ll “predict” the time span 2003 to the present, based on data from 1993 to 2003.” I note from Bob’s second graph above that there was “a decided cold fluctuation in 1993”. The words pot, kettle and black come to mind.
Alan Statham says:
January 28, 2012 at 12:55 pm
Here’s a topic for ya:
Take a closed container of air at room temperature and inject into it sufficient CO2 to raise the CO2 concentration to 5,000 PPM. After two weeks time what will be the temperature inside the container? After one month? One year? Show your work.
Tamino is a low level muppet (or should that be puppet?) in my humble opinion, so in truth, I don’t think it’s even worth a response by Mr Tisdale…..
Thanks for sending me to that site, Bob. The smugness at that place practically scorched my retinas.
I don’t know who’s right here. Presentation is half the game – facts the other.
You could try an analysis of covariance on the two slopes – not strictly valid on a time series but you could give it a go. See if the slopes of model and reality really are different (albeit with assorted caveats).
You know what they say: keep an open mind. But not so open that your brain falls out.
Reading Tommy’s post, the thought that occoured to me is that he is very familiar with data torture.
“Babsy says:
January 28, 2012 at 1:57 pm”
We of ‘The Knowing’ have every evidence we need about radiative forcing of Co2. In its trace form within Earth, it has the same radiative (heat transfer) properties as any composition of mass at equal levels in a straight line.
That, is all the evidence you really need.
Markus Fitzhenery
“I zeroed the data for my graph in 2003, which is the end year of the Hansen et al (2005) graph, to show how poorly the model projection matched the data during the ARGO-era, from 2003 to present.”
I think this quote captures it. The issue is simple. You say you are showing “how poorly the model projection matched the data during the ARGO-era”. But what you’ve plotted isn’t the model projection. You’ve altered it.
Well, I suppose you might want to think about changing the figure one so that the model trend and the argo trend both start at .02 in 2003, to make it clearer that they are what is being compared. But that just makes the difference between the two trends even clearer, so I don’t know why the warmers would call that better.
Since the previous thread appears to have faded out in favor of this one, I’ll repeat a point I made there. Tisdale is making a basic conceptual mistake with his idea of “zeroing,” much as he did an earlier post where he misunderstood “time trends.” In both cases he set out to attack other researchers but builds that attack on his own confusion about research methods.
As in the “time trends” thread, other posters have pointed out the mistake but Tisdale does not grasp what it is.
These are three quite different things:
1. The starting point for a physical model (e.g., Hansen’s). If that point is unusually high or low, but the physics are any good, the model itself should correct to more reasonable values as it runs forward.
2. The y intercept in a regression. That usually is not the starting point of the data, and the trend may well be unrealistic if you force it to be. Creating an unrealistic regression line was Tisdale’s intention here, but it’s created by his own confusion not something Hansen got wrong. No wonder folks elsewhere are laughing at him, again.
3. Anomalies. Shifting the baseline for anomalies can be done for many reasons but should have no effect on how steep either a physical or statistical model trend is. The line should be at an appropriate height as long as the model knows about the new baseline too.
Tisdale’s idea of “zeroing” here manages to confuse his own approach that does not make sense (2) with two other things that make sense in different contexts (1) or (3).
KR says:
January 28, 2012 at 12:30 pm
“Bob Tisdale – If you’re going to evaluate a linear trend prediction, you need to compare observations to the slope (which you did) and the offset (which you did not) of that prediction. ”
The only way to compare the 2 – model and observation – for the ARGO era – is to start from a common point when the ARGO era started. Any other starting point would be misleading. Why to start modelling from a lower point or maybe higher point if the presenter is skeptic? What would be any reason to give the models a different starting point? What’s up with that?
When the discussion is about ARGO era the starting point should be common at the starting of the ARGO era.
It is very clear that models do not fit the ARGO era observations. Instead of acknowledging that you attack the messenger.
Just looking at the graph you can tell the red line wouldn’t even fall within the 95% confidence nor prefiction interval of the actual data (brown line). Is that not be the definition of model fail???? How does the AGW crowd defend this?
markus says:
January 28, 2012 at 2:21 pm
It would be a simple experiment to run. Then we would know for sure. The science would be settled, we could all hold hands, and sing Kumbayah! Wouldn’t that be a grand way to bring a troubled world closer together?.
“David L says:
January 28, 2012 at 2:33 pm
Just looking at the graph you can tell the red line wouldn’t even fall within the 95% confidence nor prefiction interval of the actual data (brown line). Is that not be the definition of model fail???? How does the AGW crowd defend this?”
A. Consensus.
Score: 100%
David L writes,
“Just looking at the graph you can tell the red line wouldn’t even fall within the 95% confidence nor prefiction interval of the actual data (brown line). Is that not be the definition of model fail???? How does the AGW crowd defend this?”
There’s no “AGW crowd” here but there are a handful of people who understand data analysis. And they aren’t defending Tisdale’s graph, they’re pointing out that it is totally misleading. It is misleading because Tisdale took a regression slope and grafted that onto a starting point of his choice instead of a regression y intercept, so we have something that kinda looks like a regression line but isn’t — and it’s fooling a lot of people here.
“Babs Says;
It would be a simple experiment to run. Then we would know for sure. The science would be settled, we could all hold hands, and sing Kumbayah! Wouldn’t that be a grand way to bring a troubled world closer together?.”
Don’t waste any money on experiments, just read the translation of Baron Fouriers works on the physics of the natural world.
A physicist says:
January 28, 2012 at 1:51 pm….
That’s a joke, right? We’re all in the Skeptics club and Richard Lindzen sets the rules for us.
markus says:
January 28, 2012 at 2:49 pm
But I so wanted to verify the hypothesis! I want to BELIEVE! Now you want me to read a MATH book! Oh, the HUMANITY!
Gneiss says:
“There’s no ‘AGW crowd’ here but there are a handful of people who understand data analysis. And they aren’t defending Tisdale’s graph, they’re pointing out that it is totally misleading.”
Gneiss has no concern about what is really “totally misleading“. That’s because he’s a charter member of the cAGW crowd.☺
Gneiss says:
January 28, 2012 at 2:49 pm
“There’s no “AGW crowd” here but there are a handful of people who understand data analysis. And they aren’t defending Tisdale’s graph, they’re pointing out that it is totally misleading. It is misleading because Tisdale took a regression slope and grafted that onto a starting point of his choice instead of a regression y intercept, so we have something that kinda looks like a regression line but isn’t — and it’s fooling a lot of people here.”
You are correct as far as methodology.
What you are missing is that Mr. Tisdale used a starting point to show the large diversion that has occured now that ARGO data is available. The diversion began when the data became more certain, and has accelerated as time expires.
I reckon you have been libelled !!
Isn’t calling someone a “Fake Sceptic” the same as calling them a believer???
“Just looking at the graph you can tell the red line wouldn’t even fall within the 95% confidence nor prefiction interval of the actual data (brown line). Is that not be the definition of model fail???? How does the AGW crowd defend this?”
~David L
Clue: The red line isn’t output from a model. It’s something Bob Tisdale has made.
Clue 2: Bob Tisdale, having decided to very crudely represent the model output with a straight line (so you’re being shown things at very different detail resolutions) of his own making that he extends beyond the model output is then choosing to show you his crude extrapolation against only a small portion of some very wiggly ‘real’ data.
It’s an exceedingly poor and misleading analysis. I’d not host it on my blog.
Thanks Bob,
An excellent article (as always)!