It's the wrong dataset Gromit!

Marcel Crok writes:

This morning, there was lot of noise in the Dutch media (unfortunately in Dutch only) about new research that was claiming a dramatic warming of 4 degrees in 2050. The news report quoted Dutch econometricians from the University of Tilburg. They had done a statistical analysis of temperature data and the influence of CO2 and solar radiation and concluded that aerosols masked much more of the warming of greenhouse gases than previously thought.

Unfortunately, the econometricians concerned didn't read the instructions on the tin before use. Most amusing.

Read it here.

Weather is climate

At least according to Matt Briggs, statistician and fellow of the American Meteorological Society.

Sure is cold out there, unusually so. By “unusual,” I mean the temperature is on the low end of the observed temperatures from previous winters.

Of course, we don’t have any more than about 100 years of reliable measurements, so it’s possible that the freeze we’re experiencing now isn’t as unusual as we suspect. But, anyway, it still sure is cold.

If you recall, a lot of global warming models predicted it would be hot and not cold, and to risk redundancy, it sure is cold. Does this dissonance between the models’ predictions and what is actually happening mean that those models are wrong?

No. But it sure as ice doesn’t mean that they are right.

Schiermeier on climate uncertainties

Quirin Schiermeier has an article in Nature on the uncertainties in climate science, which will interest many readers. It tends to reiterate lines of argument that are familiar to anyone who has followed the pronouncements of the Hockey Team in recent years. This is hardly surprising when one looks at who he chose to interview - Gavin Schmidt, Jonathan Overpeck, Gabriele Hegerl, Susan Solomon, Hans von Storch, and an economist called Leonard Smith.

Not a sceptic among them and four of them being Hockey Team members.

There are many points of interest. For example, Schiermeier claims that the divergence problem is restricted to "a few northern hemisphere sites", directly contradicting Keith Briffa who has referred to it as "a widespread problem" in the NH. Schiermeier also tries to defend the Nature "trick", although perhaps without quite the certainty that Jones' defenders have had in the past. "It could have been done better", seems to be the current preferred line for those who would try to justify hiding things from politicians.

The heights of bizarre

Warmist blogger Deep Climate has been doing some detective work and has found an extraordinary similarity between a paragraph of the Wegman Report (which demonstrated that the Hockey Stick algorithm was wrong) and a paragraph of a book written by a sceptic physicist, Donald Rapp.

Here's the Wegman section:

The average width of a tree ring is a function of many variables including the tree species, tree age, stored carbohydrates in the tree, nutrients in the soil, and climatic factors including sunlight, precipitation, temperature, wind speed, humidity, and even carbon dioxide availability in the atmosphere. Obviously there are many confounding factors so the problem is to extract the temperature signal and to distinguish the temperature signal from the noise caused by the many confounding factors.

And here's the Rapp equivalent

The average width of a tree ring is a function of many variables including the tree species, tree age, stored carbohydrates in the tree, nutrients in the soil, and climatic factors including sunlight, precipitation, temperature, wind speed, humidity, and even carbon dioxide availability in the atmosphere. Obviously there are many confounding factors so the problem challenge is to extract the temperature signal and to thus distinguish the temperature signal from the noise caused by the many confounding factors.

Too similar to be accidental, I'm sure you would agree.

The Wegman Report was published in 2006, while Rapp's book appeared two years later. Now you or I would therefore assume that Dr Rapp had pinched the relevant paragraph from Professor Wegman, but in the bizarre world of climate science such simple explanations do not hold. Deep Climate concludes instead that Dr Rapp was a ghostwriter for the Wegman report.

And slowly the awful truth dawned on me. The Wegman report section was an early version of the text book chapter, not the other way around. I had just discovered a hitherto well hidden fourth author.

I'm speechless. I simply do not have the words to express how ridiculous this is. I'm not the only one either. One of Deep Climate's commenters wonders if our hero hasn't maybe got things back to front:

DC, are you sure you don’t have the plagiarism backwards? Rapp author was ripping off Wegman, rather than Wegman ripping off/collaborating with Rapp?

To which our supersleuth replies thusly:

[DC: That doesn't work. First off, Wegman has no knowledge of climate proxies at all. But suppose he or one of his co-authors wrote it. Then you have to suppose Rapp took that and extended it to three other proxies but kept the same style. And kept on going. I just can't see it. Something else is going on here ...]

If you refer back to the paragraphs quoted above, this is Paleoclimate 101 stuff - anyone who had read a few review papers on paleoclimate or the IPCC reports could have put this together. The idea that Wegman needed to get expert help to write this is simply risible. Half the commenters on ClimateAudit or RealClimate could have put that handful of sentences together.

It all smacks of a desperate attempt to try to smear Wegman, but one that is so transparent in its efforts to twist the facts to fit a preconceived conclusion that I think it will simply backfire on its author. It's just too funny.

Update on Dec 20, 2009 by Bishop Hill

Deep Climate has changed the title of his article and posted an apology to Rapp and Wegman.

Quote of the day

Hat tip to Hans von Storch for pointing out this comment in the emails. It was sent by paleoclimatologist Ed Cook to the CRU's Keith Briffa, outlining his opinions on the current (2003) state of knowledge of past temperatures:

The results of this study will show that we can probably say a fair bit about <100 year extra-tropical NH temperature variability (at least as far as we believe the proxy estimates), but honestly know fuck-all about what the >100 year variability was like with any certainty (i.e. we know with certainty that we know fuck-all).

Read that carefully people. We know a fair bit about the temperatures in the last 100 years, but only for the extra-tropics. Before that, we know nothing. Nothing.

Nothing.

Read the whole email. It's astonishing.

Update on Dec 7, 2009 by Bishop Hill

Aidey in the comments points out that I've got the nuance of this post wrong. What Aidey points out is that what Cook is saying is that we understand short-term variability (<100 years) but not long-term (>100years). What does this mean about our understanding of the much-disputed medieval warm period though?

Dendrochronology

I'm currently reading Oliver Rackham's "Woodlands".  While the dust jacket says that he's one of Britain's best known naturalists, Rackham's is hardly a name that is often cited around most British breakfast tables. This is a pity, because he has written some masterful books, including the seminal History of the Countryside. His books are full of wonderful, arcane knowledge about the British landscape and the way land use has changed over the years. Woodland and trees turn out to be wonderfully counterintuitive. For example the presence of an ancient tree in a wood is a strong indicator that the wood is not ancient. This is because in woods, trees are felled on a regular basis. So if you see an ancient tree in a wood, it probably means that a wood has grown up around an a single ancient tree. I find that rather wonderful.

Rackham is a botanist: his specialisms are trees and woodlands - as a fellow of All Souls Corpus Christi Cambridge he is an acknowledged authority on his subject - which is why I was amused to read his thoughts on dendrochronology and paleoclimatology. It's possible that I may be inferring something into his words which is in fact not there. But I can't help but get a feeling of a gentle sarcasm, a wise old man raising an eyebrow at the antics of the young.

Tree rings have other uses. Because weather varies from region to region, the provenance of a timber can sometimes be determined: if the sequence matches a master curve from Poland rather than England, this is evidence that the sample is of Baltic oak. By removing year-to-year variation, leaving the long-term trends, it has been possible in America to use growth rates as a measure of climate change.

To get a result one normally measures at least 100 rings, preferably from each of several contemporary trees or timbers. Tree rings are affected by other factors besides weather, such as defoliating caterpillars. In view of the statistical 'noise' introduced by unknown factors, it is surprising that the method has been so successful and so seldom at odds with dating by other means. 

[Emphasis is mine]