Monday, December 28, 2009


You know you have been dissed, when the folks who created the procedure you used call you out on it. Nicky Scafetta and Dick Willson have been dissed. However, like all good stories this needs an introduction. One of the tragedies of solar astronomy, is that the launch of the replacement for the first total solar irradiance (TSI) monitor was delayed for two years. Accounting for what happened in the gap between ACRIM 1 and ACRIM 2 is the major problem in constructing a TSI record although there are others (google PMOD, IRMB and ACRIM). How to fill that gap using other observations is an issue as bunnies might believe.

Scafetta and Willson (open preprint) used a model called SATIRE-T. They found an increase in the TSI from 1986 and from that, in other papers, Scafetta ascribed a significant part of the global temperature increase to an increase in the TSI. Scafetta has been caught on tape selling this shinola.

In record time, a "comment" on Scafetta and Willson's ACRIM reconstruction, published in GRL earlier this year has appeared in December. Krivova, Solanki and Wetzlar calmly mentioned that Scafetta and Willson screwed up. A preprint is available at arXiv

Solanki and Krivova created a suite of models they named SATIRE to estimate solar irradiance from observations of changes in the solar magnetic field. Each model had a specific purpose. SATIRE S was designed to be used when there were direct, full disk measurements of the solar magnetic field in the photosphere. Changes in the magnetic field and images of the solar surface can be used to figure out the TSI. This is a good place to be, because it infers TSI with a minimal number of assumptions from a fair amount of useful data.

On the other hand, it is only in the satellite era (post 1974) that Rabett Labs had such information, so if Eli wants to go further back, say to the Maunder Minimum, all we got are observations of the sun, including sunspots, and another model is needed and that is SATIRE-T, T standing for Telescope. It is set up to look at longer period changes in TSI, on the decade to century time scales and is known to be less accurate on periods of months, but since all we have going back hundreds of years is sunspot evolution, it is about as good as it gets. Krivova, Solanki and Wetzlar point out that

Thus, by its very conception, the model by Krivova et al. [2007] employed by Scafetta and Willson [2009] is expected to be relatively accurate on time scales of days to the solar rotation and from the solar cycle to centuries, whereas its accuracy on time scales of several months to years is limited. This is exactly opposite to what Scafetta and Willson [2009] assumed.
Rather than the increase in TSI from 1986 that Scafetta and Willson found using the wrong model, SATIRE-T, Krivova, Solanki and Wetzlar find a small decrease when using SATIRE-S, but caution that the decrease is small, and only magnetic effects are considered by the models
The magnitude of this decrease cannot be estimated very accurately from such an analysis (and therefore such a ‘mixed’ composite should not be considered as a replacement of real measurements), but it lies between approximately 0.15 and 0.7 Wm−2 (0.011–0.05%) for different values of the model’s single free parameter. Note that irradiance changes due to non-magnetic effects, if any, cannot be revealed by either SATIRE-S used here nor by SATIRE-T employed by Scafetta and Willson [2009].
Now there are many (not Eli, the bunny would hasten to add) who might think that the wrong choice of model was made for some (unknown to Eli) ulterior purpose (which Eli would never even speculate about). Still, in this case it probably will not be necessary to demand the code from Scafetta but, in the nature of such things it has popped up in many of the predictable places. While it is not likely that many of the usual blogs would even consider doing so, Eli looks forward to the following eminent authorities amending their claims

Comments on Draft Technical Support Document for Endangerment [PDF]
A Carlin - US EPA internal document intended for …, 2009 -
These comments were prepared during the week of March 9-16, 2009 and are based on the March 9 version of the draft EPA Technical Support document for the endangerment analysis for Greenhouse Gases under the Clean Air Act. On March 17, the Director of the National ...
Cited by 2 - Related articles - View as HTML - All 18 versions

Scientific Shortcomings in the EPA's Endangerment Finding from … [PDF]
PJ Michaels, PC Knappenberger - Cato Journal, 2009 -
On April 24, 2009, the US Environmental Protection Agency issued a finding of “proposed endangerment” from climate change caused by six greenhouse gases, with the largest contributions to warming resulting from emissions of carbon dioxide and methane (EPA 2009a). The ...

Request for Extension of Comment Period, Or in the Alternative, for the … [PDF]
TWIM Concern -
EPA Docket ID Number EPA-HQ-OAR-2009-0171 _____________________________________________________

Countering Kerry's Catastrophic Climate Claims
KP Green -
Kerry asserted that not one peer-reviewed paper contradicts the “consensus” view that greenhouse gas emissions will cause devastating consequences, and that we must limit their emissions radically to avoid the maximum “consensus” value of two degrees Celsius, which Kerry claimed ...


John Mashey said...

Well, maybe Scafetta can move from TSI to Rhodes Fairbridge, also in that talk.

Bunnies may recall that this effort is fed by your tax carrots:

"NS thanks the Army Research Office for support (grant W911NF-06-1-0323)."

Of course, Bruce West is at ARO...

Unknown said...

What is amusing in reading Alan Carlin's document is his claim that in less than a week of lit review he was able to find "major holes" in established climate science that undermine decades of theory and research performed by hundreds of scientists.

The sheer hubris is unreal.

Anonymous said...

What has always struck me about the claims of Wilson et al is that they were made based on just a few solar cycles.

Change within a few cycles hardly be considered an upward trend, even if it has been accurately measured (which it was not in this case because of the gap)

John said...

Isn't there a word missing in paragraph #4?

SATIRE S was designed to be used in the [WORD MISSING?] where there were direct, full disk measurements of the solar magnetic field in the photosphere.

Arthur said...

Isn't there an old "ACRIM" TSI reconstruction (that Scafetta et al have been using for years, and claiming was better than PMOD)? Their whole argument rests on an absurdly high climate sensitivity to solar forcing anyway (and somehow no sensitivity to CO2).

EliRabett said...

Thanks John, Eli fixed it

erikH said...

This paper just submitted to Physical Review Letters is quite negative with respect to the statistical procedures utilized by Scafetta

David B. Benson said...

Bunny pellets?

Unknown said...

The comment erikH linked to has a key idea in the conclusion: the climate system has a lot of inertia and the short-scale vagaries of TSI cannot meaningfully perturb something with that much inertia at scales the denialists trumpet.



Word verif harrumphs: casmo

Unknown said...

What is that old sexist statistics joke? "Statistics are like women. Once you get them down you can do anything you want." Since I started reading up on this bunny balls stuff I have noticed quite a few statistical errors due to preconceived notions of various authors. The TSI climate link is one of the most humorous on both sides of the debate.

Boris said...

I tried to click on the Mihcaels Krappenburger link, but Firefox, wiser than I apparently, informs me that the site is untrusted.

word verification: colying

The system became self aware at 3:34 AM EST on January 1, 2010.