On Critique #1:
Since you are using Real Climate and Skeptical Science as sources, did you read what they had to say about the Armstrong and Green paper and about Nate Silver's chapter?
Gavin Schmidt's post was short, funny but rude; however ChrisC's comment looks much more damning if true. Is it true?
Here is Skeptical Science on Nate Silver. It seems the main cause of error in Hansen's early 1988 forecast was an assumed climate sensitivity greater than that of the more recent models and calculations (4.2 degrees rather than 3 degrees). Whereas IPCC's 1990 forecast had problems predicting the inputs to global warming (amount of emissions, or radiative forcing for given emissions) rather than the outputs (resulting warming). Redoing accounting for these factors removes nearly all the discrepancy.
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In light of the portions I quoted from Armstrong and Green's paper, I'll look at Gavin Schmidt's post:
The paper does cite many other sources than just the IPCC and the "hatchet job" on the Stern Report, including sources that evaluate climate models and their quality in general. ChrisC notes that the author's fail to cite the ~788 references for the IPCC Chapter 8. The authors claim to have a bibliography on their website that includes the full list of references given to them by all academics who suggested references. Unfortunately, as I noted in my earlier comment, the link to the bibliography from http://www.forecastingprinciples.com/index.php?option=com_content&view=article&id=78&Itemid=107 is broken. This doesn't reflect well on the authors (the site on the whole is a mess, with many broken links). Assuming, however, that the authors had put up the bibliography and that it was available as promised in the paper, this critique seems off the mark (though I'd have to see the bibliography to know for sure).
This seems patently false given the contents of the paper as I quoted it, and the list of experts that they sought. In fact, it seems like such a major error that I have no idea how Schmidt could have made it if he'd read the paper. (Perhaps he had a more nuanced critique to offer, e.g., that the authors' survey didn't ask enough questions, or they should have tried harder, or contacted more people. But the critique as offered here smacks of incompetence or malice). [Unless Schmidt was reading an older version of the paper that didn't mention the survey at all. But I doubt that even if he was looking at an old version of the paper, it omitted all references to the survey.]
First off, retrospective "predictions" of things that people already tacitly know, even though those things aren't explicitly used in tuning the models, are not that reliable.
Secondly, it's possible (and likely) that Armstrong and Green missed some out-of-model tests and validations that had been performed in the climate science arena. While part of this can be laid at their feet, part of it also reflects poor documentation by climate scientists of exactly how they were going about their testing. I did read that IPCC AR4 chapter that Armstrong and Green did, and I found it quite unclear on the forecasting side of things (compared to other papers I've read that judge forecast skill, in weather and short-term climate forecasting, macroeconomic forecasting, and business forecasting). This is similar to the sloppy code problem.
Thirdly, the climate scentists whom Armstrong and Green attempted to engage could have been more engaging (not Gavin Schmidt's fault; he wasn't included in the list, and the response rate appears to have been low from mainstream scientists as well as skeptics, so it's not just a problem of the climate science mainstream).
Overall, I'd like to know more details of the survey responses and Armstrong and Green's methodology, and it would be good if they combined their proclaimed commitment to openness with actually having working links on their websites. But Schmidt's critique doesn't reflect too well on him, even if Armstrong and Green were wrong.
Now, to ChrisC's comment:
Part of the authors' criticism was that the climate science mainstream hadn't paid enough attention to forecasting, or to formal evaluations of forecasting. So it's natural that they didn't find enough mainstream stuff to cite that was directly relevant to the questions at hand for them.
As for the Google search and Google Scholar search, these are standard tools for initiating an inquiry. I know, I've done it, and so has everybody else. It would be damning if the authors had relied only on such searches. But they surveyed climate scientists and worked their way through the IPCC Working Group Report. This may have been far short of full due diligence, but it isn't anywhere near as sloppy as Gavin Schmidt and ChrisC make it sound.
Thanks for a comprehensive summary - that was helpful.
It seems that A&G contacted the working scientists to identify papers which (in the scientists' view) contained the most credible climate forecasts. Not many responded, but 30 referred to the recent (at the time) IPCC WP1 report, which in turn referenced and attempted to summarize over 700 primary papers. There also appear to have been a bunch of other papers cited by the surveyed scientists, but the site has lost them. So we're somewhat at a loss to decide which primary sources climate scientists find most credible/authoritative. (Which is a pity, because those would be worth rating, surely?)
However, A&G did their rating/scoring on the IPCC WP1, Chapter 8. But they didn't contact the climate scientists to help with this rating (or they did, but none of them answered?) They didn't attempt to dig into the 700 or so underlying primary papers, identify which of them contained climate forecasts, and/or had been identified by the scientists as containing the most credible forecasts and then rate those. Or even pick a random sample, and rate those? All that does sound just a tad superficial.
What I find really bizarre is their site's conclusion that because IPCC got a low score by their preferred rating principles, then a "no change" forecast is superior, and more credible! That's really strange, since "no change" has historically done much worse as a predictor than any of the IPCC models.