Here are some first thoughts. So far I don’t see anything in W-A that affects any of our results. Indeed, I expect that W-A is going to be very positive for this debate, as the points at issue are going to be narrowed sufficiently closely that any people actually interested in the results (as opposed to spin) will be able to finally compare apples and apples. It will require a little cutting through the packaging, but since they’ve commendably provided code for the first time, it won’t be too hard.
As I work through their code in the next few days, I will highlight any points of methodological difference and and will immediately provide notice of the issue. This is what you’re supposed to do in public businesses (and most businesses do) and it’s a good policy.
One of the first questions that readers of this site have had e.g. Paul Gosling – what happens without the bristlecones. Here’s a cutout of their run archive without bristlecones
In Hockey Team style, they provide a spaghetti graph so that it makes it more difficult to examine the individual calculation. However, you can pretty much see the purple calculation up to the end. The legend says that if the bristlecones are omitted, the calculation is "without merit".
It will be interesting to see how they comment on Mann’s grandiose claims that their reconstruction was "robust" to the presence/absence of dendroclimatic indicators in total (since a very quick inspection of this graphic confirms our report that this representation was false.) It will also be interesting to see their explanation as to how – if a reconstruction without bristlecones is "without merit" – a calculation with bristlecones can possibly have any merit in the face of our many criticisms of bristlecones not only as a flawed proxy, but as a proxy with flaws known to Mann et al.
In any event, the graph below shows that they don’t get a hockey stick without bristlecones either.
Figure 1. Excerpt from figure on Amman’s ucar website.
Continue reading →
Just got back from Washington a few minutes ago (I think that the presentations went very well) and saw this press release from Wahl and Amman (link). The points appear to be ones that have been posted up at realclimate before, which we’ve fully considered and, in my opinion, don’t lay a glove on our criticisms. Here are the links as sent to me. I’ll post up some more comments after I’ve had a chance to look at it. Continue reading →
Benny Peiser sent in this link to a speech delivered by David Henderson, formerly head of the department of Economics and Statistics at the OECD. What it’s really about is the rise of an illiberal, collectivist and anti-market economic consensus in important political insitutions and western societies in general. But it also touches upon issues of the politics of climate change and the IPCC.
First, what do I mean by global salvationism? The salvationist doctrine has
two main strands, which originally were separate but have long since come
together to form an influential world-wide consensus. The first strand is
developmental salvationism, and relates to the economic fortunes of poor
countries. The second strand is environmental salvationism. In both strands,
two elements are combined. One is a relentlessly dark – not to say alarmist –
picture of recent trends, the present state of the world (or ‘the planet’),
and prospects for the future unless prompt and far-reaching changes are made
in official policies. The second is a conviction that known effective remedies
exist for the various ills and threats thus identified, remedies which require
action on the part of governments and ‘the international community’. ‘Solutions’
are at hand, given wise collective resolves and actions. Global salvationism
thus combines alarmist visions and diagnoses with confidently radical collectivist
prescriptions for the world.
Continue reading →
Ross McKitrick and I will be making two presentations in Washington on May 11 sponsored by Cooler Heads Coalition/George Marshall Institute: 12.20 at the National Press Club and 3 pm somewhere on Capitol Hill.
At present, I’m having trouble figuring out what on earth is going on with MBH confidence intervals. Here is a figure showing the one-sigma confidence intervals in MBH98 (cyan) and MBH99 (salmon).
Figure 1. MBH98 and MBH99 one-sigma by calculation step. Cyan – MBH98; salmon – MBH99. Solid black – CRU std dev; dashed red -“sparse” std. dev. The MBH98 sigma is calculated from confidence intervals in NOAA MBH98 archive here; the NBH99 sigmas are from NOAA MNH99 archive here.
Continue reading →
I’ve been looking at MBH98 confidence interval estimation. There are many puzzles as to methodology. Here I’ll touch on some archiving oddities.
Figure 1. Standard error (“sigma”) of MBH98 Reconstruction Steps. Calculated from confidence intervals for MBH98 reconstruction at NOAA archive here. Continue reading →
Here are some thoughts from 70 years ago from the eminent statistician, R.A. Fisher, from the “Design of Experiments”. There’s a nice dig about “heavyweight authorities”. Continue reading →
Apologies for the delay on this article. We’ve now fixed the weblog issue
The BBC reports on yet another discovery of the "Smoking Gun" of anthropogenic global warming.
Continue reading →
Roger Pielke at Prometheus [archive] as some kind words for my comments on the IPCC “editing” of the Briffa MXD series in their spaghetti graph.
Good for Chris Mooney and good for Climate Audit. Such close attention can help both the IPCC and NASA realize that people are paying attention to their use of information and facts. Knowing that people are paying attention will mean that NASA and IPCC may be less likely to go beyond cherry picking to providing information that is mistaken or mischaracterized. NASA and IPCC (and bloggers as well) should care because if people come to learn that their information providers are playing fast and loose with facts and information, then with some audiences their institutional legitimacy and authority may be placed at risk.
Anytime someone uses facts or information to make an argument, that use is selective. Cherry picking is inevitable. But it is important to recognize that how one uses information can either foster or damage legitimacy and authority (on this, see recent reports on use of intelligence leading to the war in Iraq).
The “Index of Leading Environmental Indicators 2005” of the Pacific Research Institute says the following:
“The “hockey-stick” graph, believed to be one of the leading indicators of global warming, is now being called “rubbish.” Scientists have shown that the graph’s underlying equation would generate the same result for any series of random numbers."
In another location, a Pacific Research writer says:
Scientists agree that global temperatures have risen about 0.6 degree Celsius over the past century. But the famous "hockey stick" graph claiming to prove that the past 25 years have been the warmest in the past 1,000 years cannot be taken seriously. Experts have shown that the computer algorithm used to generate the graph would produce similar results from any series of random numbers.
The “rubbish” claim is based on a quote from von Storch, although we obviously do not disagree with von Storch on this matter. Making the reasonable assumption that the last statement of each excerpt refers to our work, neither version is exactly what we said. Ross has sent them an email me notifying them of our actual statements. In connection with an article, I re-visited MBH simulations and did some simulations, which confirm that the generation of hockey-stick shaped PC1s carried into hockey-stick shaped reconstructions. The hockey stick shape is somewhat attentuated, but the degree of attenuation in the simulations almost exactly matched the attenuation between the MBH98 NOAMER PC1 and their reconstruction. Very high spurious RE levels carry over. more
Climate Audit 
Upcoming Washington Trip
Ross McKitrick and I will be making two presentations in Washington on May 11 sponsored by Cooler Heads Coalition/George Marshall Institute: 12.20 at the National Press Club and 3 pm somewhere on Capitol Hill.