People ought to hang for this. Not just the people who did it, but the people who we relied on to screen fact from fiction, whose word was taken that this was all true. They had a solemn responsibility to conduct due diligence and many of them took the food from the mouths of your children to support them for this purpose.

This isn’t ‘ha-ha’ funny at all.

The bristlecone records seemed a lousy proxy, because at the altitude where they grow it is below freezing nearly every night, and daytime temperatures are only above freezing for something like 10% of the year.

I’ve been to the bristlecone pines several times in the summer, having camped and climbed nearby White Mountain (14,420′) three times. Mr. Shaw’s assertion is false.

While it’s rarely WARM in the White Mountains, temperatures are above freezing for much more than 10% of the year, and there are many summer *nights* where the temperature is above freezing, necessitating only a light sleeping bag. I have stood on top of White Mountain (3500 feet above the Bristlecone forest) in shorts and a light shirt in July without being cold at all.

I can’t immediately find complete temperature data, but please see

http://www.fs.fed.us/database/feis/plants/tree/pinlon/all.html

and search on “temperature.” You will eventually come to the sentences

In July and August, mean monthly temperatures average 50 °F (10 °C). Mean monthly temperatures are below freezing from November through April.

I have no views on the suitability of bristlecone pines as proxies, though from what I’ve read I agree with the skeptical position. But I think we should start by simply getting our facts correct.

In order to use a tree as a climate metric you need to understand its surroundings, how it grew over time and how its surroundings changed. Just like weather stations, you can not apply a “one size fits all” equation. Thats something academics do all to often unfortunetly, and they just love the “black box” approach!

I have seen growth patterns much like YAD061 in the rings of many stumps in New Hampshire, and not once have I thought it showed a sign of global warming, or of increased levels of CO2 in the air. Rather the cause is far more simple: A childhood in the under-story, followed by a tree’s “day in the sun.”

Right, fully right.

A better proxy could be the whole production per hectare, because you will loose the individual effect of competition between trees. But on long period, we haven’t these datas. In natural forest, with irregular stands, the competition between young trees (or young trees and other plants) is very hard. The whole trees in the graphic show the same pattern at the begining of their life.

I thought you seemed more erudite than the average lumberjack. ;-)

” Briffa has also studied tree rings in Sweden at Torneåträsk (1992). A recent study found out that the adjustments made Briffa wiped out MWP. The new study, with more tree samples, makes it clear that MWP was the warmest peiriod in the last 1500 years there.

See http://people.su.se/~hgrud/documents/Grudd%202008.pdf ”

No doubt some readers didn’t notice or didn’t have time to look at that pdf. But doing so is well worthwhile if only because it shows these papers don’t have to be nearly incomprehensible to get published.

It is about as clear an explanation of dendrochronology in action as an amateur will encounter. It also is useful for those interested in the Briffa Yamal matter.

Therefore I would like to clarify that the reason I have spent so much time working in the woods is not because I am a successful lumberjack, but rather because I am an unsuccessful writer.

If you have any experience with writers you know that a major aim of all writers is to avoid working a real job. If my life had followed the script I wrote for myself as a teenager, I never would have worked a real job at all. I only worked real jobs because I ran out of people to mooch off. Therefore I should not be equated with honorable people like “Joe the Plumber.”

Many unsuccessful writers reach a point where they have to decide just how far they will go, to avoid getting a real job. Will you lie? Will you forge? Will you steal? Will you sleep with the editor?

Being something of a prude, I would not go as far as some of my peers would, to get published. Some suggested this explained my lack of success, (though I myself think the reason for rejections was that my writing put people to sleep.)

One trick, which my fellow writers seemed very adept at, was to get people to pay them for work they hadn’t done, and likely would never get around to doing. It was called “an advance,” and I had friends who were very good at getting advances. To me they seemed more like con artists than true artists. They were slick talkers, and landed an advance or endowment or grant, and spent all the money on wine, woman and song, and then awoke with terrible hangovers, flat broke. They called awaking with hangovers and being flat broke “the suffering of an artist,” and sometimes got patrons to pity them, and earned further grants and endowments and advances. It was quite a racket, but I was no good at it, and wound up washing dishes or cutting trees in the woods. Eventually I stopped telling people I was “a writer,” and just called myself “a landscaper and handyman.”

Therefore, if you judge a man by the company he has kept, it should be obvious I don’t deserve some of the flattering comments people have showered on me. However I did learn one thing, during my time as an unsuccessful writer, and that was: “How to recognize a con-artist.”

Naming no names, I often have felt I recognized the work of con-artists in the work of climate scientists, and have rudely and bluntly said as much. Over at Climate Audit my comments were quite regularly snipped, because I was too blunt. I feel Steve McIntyre deserves a great deal of credit for not allowing people like me to be rude and blunt, and to turn his site into a free-for-all. Rather than making accusations he keeps his cool, and politely states, “Excuse me, but it seems you made a mistake here.” I hugely respect his calm and collected manner, and am trying my best to learn how to emulate it.

In the end I feel remaining calm and collected will bring truth back to the science of climate. Also I believe people will eventually learn as I have learned, and recognize real jobs are better than con jobs.

No human intervention needed, natures processes can produce the variety of patterns we see in remote and ‘pristine’ areas, including trees which suddenly show growth spurts.”

Quite right, and in arctic and northern temperate areas, a late spring or early fall ice storm can coat trees with ice to load them down and tear them down. I’ve lived through such storms, feels like you’re in a war zone as the trees crack and collapse around you. Next day the forest is much more open.

2: as things stand, there is available no quick or easy guidance about what to believe, not only on the many matters over which apparently competent people differ but also over some where the experts seem to be in agreement. At times we do well to believe what we’re told; at other times we had better not. Sometimes there’s no better guide than the experience of what you’ve seen for yourself; at other times your eyes deceive you. We should be open to new ideas—but on the other hand we should always be skeptical and critical before accepting a new idea, for old beliefs are often well tested by experience whereas new ones may just be untested hunches. It’s good to see the whole picture, to be holistic, to be interdisciplinary—but on the other hand in many fields progress requires concentration on ultraspecialized techniques, theories, and facts.

233: (Quoting I. J. Good 1978:337): “Many fallacies … have their origin in wishful thinking, laziness, and busyness. These … lead to oversimplification, the desire to win an argument at all costs (including the cost of overcomplication), failure to listen to the opposition, too-ready acceptance of authority, too-ready rejection of it, too-ready acceptance of the printed word (even in newspapers), too great reliance on a formal machine or formal system or formula (deus ex machina) … special pleading, the use of language in more than one sense without noticing the ambiguity (if the argument leads to a desirable conclusion), the insistence that a method used successfully in one field of research is the only appropriate one in another, the distortion of judgment, and the forgetting of the need for judgment.”

Gavin, there appears to be a tension between the climate record as reconstructed using tree rings and that from tree lines.

Rashit M. Hantemirov* and Stepan G. Shiyatov (2002) A continuous multimillennial ring-width chronology in Yamal, northwestern Siberia. The Holocene 12,6 pp. 717–726
http://www.nosams.whoi.edu/PDFs/papers/Holocene_v12a.pdf

Page 720 shows how tree lines have moved South over the last 7000 years, reflecting decreasing temperatures at the Northern tree line.
Conversely the tree ring data, from the same location, says that 20th Century temperatures are unprecedently high.

What’s going on?

Mike, you say “Response: Forest ecosystems respond to climate forcing on multi-generational timescales. Evidence from fossil pollen, tree lines, etc. can thus in general only be used to infer climate change on multi-century timescales. They cannot be used to infer decadal timescale changes such as the anomalous warming of the past few decades.”

Yet Esper and Schweingruber report “larger-scale patterns of treeline changes related to decadal-scale temperature variations”.

Esper and Schweingruber (2004). Large-scale treeline changes recorded in Siberia. Geophysical Research Letters 31.

Again this is confusing since I know that Esper is one of your co-workers.

So do tree lines shift on centennial or decadal timescales?

[Response: This characterization is misleading. Esper and Schweingruber were not looking at the shift of treelines in the usual sense (e.g. as determined in the more distant past by looking at relict stumps, etc.). Instead, they were looking at the modern past (20th century) where other sorts of evidence can be established to look at far more subtle shifts in the ecotomes, e.g. the germination dates of saplings, whether they were upright or not, etc. This sort of more subtle evidence cannot be extended to past centuries, hence they are unable to provide a quantitative reconstruction of past temperature in the past, and certainly don't attempt any such thing in this paper. Moreover, even if they were able to do this, the migration of the treeline depends on factors such as permafrost distribution which is greatly influenced by winter temperatures. Tree-ring growth in these regions, however, is generally reflective of summer temperatures. So even if a quantitative reconstruction from treelines were available, it wouldn't even be comparable in terms of the seasonality reflected by the record. In short, there is nothing there that challenges the quantitative climate reconstructions provided by tree-rings. Take your talking points elsewhere. -mike]