For all the hubub surrounding Dr. Michael Mann’s hockey stick, the MWP, and throwing out data past 1960 because it didn’t seem to calibrate against the instrumental record, here is a way to put an end to the issue. Have Mann’s, Briffa’s and others tree ring samples submitted to isotope analysis. Given how much UEA and Penn State want to protect their research reputations, it seems to me that this would be an excellent way to settle the issue independently. Unless of course, they threw away the original samples. – Anthony
From a press release by the Arctic Institute of North America
Carbon and oxygen in tree rings can reveal past climate information
Isotope analysis provides accurate information
OTTAWA, DECEMBER 2009 – The analysis of carbon and oxygen isotopes embedded in tree rings may shed new light on past climate events in the Mackenzie Delta region of northern Canada.
Scientists have long looked at the width of tree rings to estimate temperature levels of past years. Larger rings indicate more tree growth in a season, which translates into warmer summer temperatures. But the analysis of carbon and oxygen isotopes in tree rings can also provide accurate data on past climate events, say researchers working in northern Canada.
In a paper published in the most recent issue of the journal of Arctic, Antarctic and Alpine Research, Trevor Porter, a PhD student in Geography and Environmental Science at Carleton University, and three other authors compared temperature data collected in Inuvik, Northwest Territories (NT) since 1957 with their own analysis of isotopes found in white spruce trees in the Mackenzie Delta region of the NT. They found a strong correlation between the two data sets and temperatures.
“Isotope analysis is a good way to measure past climate change,” says Porter about the results.
Isotope analysis is not a new way to measure past air temperatures. However, the method has not been widely used because lab costs have been prohibitive, especially when compared with the examination of tree ring width. Now, however, the cost of equipment has dropped substantially making it more affordable for researchers to use this method.
Porter’s work was carried out on the northern edge of the boreal forest in the NT where trees are small but surprisingly old. “A 15 to 20 cm. tree could be a 300 to 400 year old tree,” says Porter.
This slow rate of growth actually helps researchers because smaller trees stay standing longer. Trees that fall begin to decay making data analysis difficult or impossible.
“Once they get too large, it’s difficult for trees to persist. They are susceptible to wind and ice storms. One of the reasons trees (in the North) persist so long is because they don’t grow as much,” says Porter.
Isotope analysis allows researchers to conduct their work using a smaller sample size than needed when trying to re-construct temperature records using tree ring width. Porter explains that the width of rings can vary considerably between trees even when they are growing in the same stand. This variation can complicate reconstructions of past climate.
A number of factors influence ring size, including the age of the tree and the location of the tree within the forest. Older trees tend to have smaller rings than younger trees. And trees within the same area might not all receive the same amount of light, nutrients or even water.
“Growth is controlled by many things . . . they (trees) can all end up just a little bit different,” says Porter.
Isotope signals, on the other hand, are often very similar between trees. This means researchers can gather accurate data from three or four trees instead of the 20 they might need for tree ring width analysis.
“In ring widths there will be more variability between trees. There will be similar trends, but you have larger differences that you would find between the isotopes of different trees,” says Porter.
Porter is hoping his work will lay the foundation for a model that can be used to investigate the long-term climate history of the Mackenzie Delta region. Although the temperature record for Inuvik only dates back to 1957, the dead and live tree ring record stretches to nearly 1000 years before present. That prospect excites the young researcher.
“The tree ring record goes back almost a thousand years in this area, but it’s never been used for a temperature reconstruction. This is a really exciting time to work in climate research, especially for a young student,” he says adding, “This is a hot topic.”
More information can be found at www.arctic.ucalgary.ca
See this press release in PDF form here
I am assuming they mean CO2 isotopes?
Great, wean the Team off the bio stuff and onto isotopes…
…so long as the science is transparent and open to truly independent replication…
“Isotope signals, on the other hand, are often very similar between trees. This means researchers can gather accurate data from three or four trees instead of the 20 they might need for tree ring width analysis.”
Brilliant! We can go from “the most influential tree in the world”, to “the most influential four trees in the world.” Now that’s what I call progress!
I’m with jcspe (15:48:42) and Splice (15:49:24) on this one: let’s make sure the methodology is sound before even semi-endorsing it.
BTW, thanks to Anthony for drawing attention to this promising (?) proxy.
Hmmm, well there are fashions in research and regardless of the merits of this approach of studying past temperatures via isotope studies of tree rings, the world may not be receptive. Indeed, it may well soon turn out that the world has had such a bellyful of temperature reconstructions of any sort based on tree rings, that it reacts with hostility to any practitioners.
You have to time these things right and account for human nature.
Im still wondering how any future analysis of any new data can truly be trusted?
Maybe my paranoia is ramped up somewhat, but wont it just be “made” to fit the global warming hypothesis, come what may?
How can it be avoided?
I can’t help myself. The picture of all the equipment and gadgets reminded me of what a man said when we were boarding an aircraft for a flight and he looked into the cockpit. He said”, Wow,what a bunch of barometers!”
Sorry, we have a binding contract with the trees that precludes us from providing samples for analysis.
rbateman, how and to whom do I get the information I’ve done?
It seems some journalist with reputations to defend are beginning to do somewhat credible coverage on climate in defiance of their corporate masters wishes.
NBC Nightly News Takes Up ClimateGate, But Frets It Could ‘Delay Taking Action’
http://www.msnbc.msn.com/id/3032619/ns/nightly_news#34281922
The most recent “news” on the IPCC page:
http://www.ipcc.ch/news_and_events/news_and_events.htm
is a speech by an Indian on 22 September.
They are unaware of the storm outside??
Bingo, it always seemed so sloppy to try and use ring width as a temperature proxy given all of the grow factors which drive them, temperature being just one of several.
As has been said before, start over, using this method and all of the BEST available science to reconstruct the temperature record.
P Walker: very stable… As I understand it, the carbon isotopes give an indication of water-use efficiency, and the oxygen and hydrogen isotopes give a fair indication of source water type & origin. This type of analysis is not entirely clean, however. For example the carbon isotopic composition can indicate water-use efficiency, but this varies with temperature, leaf-to-atmosphere vapour pressure deficit (which tends to be positively-correlated with temperature) and soil moisture availability. In a nutshell, an unstressed and well-watered C3 plant will have a relateively low, species-specific delta 13 C composition, but values increase with water stress. Often, water stress is correlated with temperature, but it doesn’t take an ecologist to figure out from the above that the relationships are imperfect. The stable oxygen and hydrogen isotope also have some issues, as eluded to above. Still, I believe the effort recommended is worthwhile, if done by people who understand how to deal with the above (and it would be). I am fairly sure that some of this has been done before… I have no idea if this has been done on these samples. Anyone?
don’t forget we current use 1 themometer for hundreds of miles to measure temperature.
“This is a really exciting time to work in climate research, especially for a young student,” he says adding, “This is a hot topic.”
Lots of money out there for “young students” pursuing “hot topics”!
I’m planning to call my contacts at the university which granted my graduate degree and inform them that I will immediately cease all financial and volunteer support that I provide them until they announce that they will remove (or, at least, investigate the use of) graphs and charts which have now been called into question from their website. I refuse to support a university which is putting it’s scientific reputation at risk.
I will say that it’s a risk for them to continue using such information despite the existence of investigations at Penn State and CRU.
While I don’t think the loss of my individual support will pressure them in any way, I think some action may be taken if enough alumni did the same thing.
I’d appreciate some feedback on this.
Proper chemistry and physics at last !!
wobble (16:35:14),
Feedback: Most alumni associations have class lists, so you can contact other alumni. Refer them to WUWT while you’re at it.
I am assuming they mean Carbon isotopes? And in what way has this new discovery been subjected to falsifying attempts? Or is this going to be another skip-over-scientific-methods fad?
Whenever the isotope discussions get going on the skeptical websites, there is always a “Splice (15:49:24) (15:59:55)” commenter who throws out just enough jargon and doubt about using the isotopes that the discussion just ends.
Then Splice dissappears.
Yet the climate research community are using the isotope data every day.
Zachos 2001 dO18 isotope database has been cited in the peer-reviewed literature every second day (that is not a typo) since it was published.
Skeptical researchers have as much right to use the information from the isotope data and if Splice thinks it is being used improperly in the climate research community, then a peer-reviewed paper describing all the problems and throwing out all the data should be prepared.
What we have here is another correlation/causation argument and another, more expensive, attempt to use trees as thermometers. What is the relationship between isotopes and temperature? Is there some emperically established physical rule here?
Thank God Copenhagen begins 2 days and will last till the 18th. This will insure Climategate news stays at the top of blogosphere news and perhaps be covered by the corporate networks better.
Pamela Gray (16:48:22) :
… And in what way has this new discovery been subjected to falsifying attempts? Or is this going to be another skip-over-scientific-methods fad?
Excellent question!
“No amount of experimentation can ever prove me right; a single experiment can prove me wrong.” Albert Einstein
“Isotope analysis is not a new way to measure past air temperatures. However, the method has not been widely used because lab costs have been prohibitive”
Heck, what’s a few hundred thousand dollars more to the well funded climate science arena.? Subpoena the logs. Get it done.
I don’t like it.. yet.
From a mesuration point of view we were already in lala land with selecting just a couple of dozen trees.. now we accept just 3-4?
When these guys have done a few thousand calculations on many trees on maybe 100 sites, married the results to suitable temperature recording over a number of years.. then I’ll be interested.
I don’t know beans about this proposed science, but I know trees and how they vary sometimes quite dramatically within the same species and even clones.. thats why in a 1000ha block all planted in the same year, same species, known clones, precise spacing we don’t get decent PLEs without a 2% sample, ie, actual measurement of maybe 2000-20,000 trees in gridded plots laid over the entire area depending of stems per hectare.
Yep, we can do a Quadi (Quick and dirty) survey of a few dozen trees that’ll give us a good indication of what we’ve got, but try telling a judge that the “science is settled” or there’s a “consensus” about the tree characteristics when we could get sued for millions for getting it wrong on a forest sale.
And thats the point.. there’s no “balls on the line” for these jokers if they get it wrong.. no being sued for millions (or trillions in the AGW game) if they get it wrong or fudge the results.
There’s only one defense in court, and thats if you have followed a transparent process of recognised rigour that can be repeated, plus a page of disclaimers.. then you might walk away with at least one testicle and possibly only a slightly dodgy reputation.
JC
Will astrophysicists be allowed in the debate?
“Key Excerpts: Observations of the Sun show that as for the increase in temperature, carbon dioxide is “not guilty” and as for what lies ahead in the upcoming decades, it is not catastrophic warming, but a global, and very prolonged, temperature drop. […] Over the past decade, global temperature on the Earth has not increased; global warming has ceased, and already there are signs of the future deep temperature drop. […] It follows that warming had a natural origin, the contribution of CO2 to it was insignificant, anthropogenic increase in the concentration of carbon dioxide does not serve as an explanation for it, and in the foreseeable future CO2 will not be able to cause catastrophic warming. The so-called greenhouse effect will not avert the onset of the next deep temperature drop, the 19th in the last 7500 years, which without fail follows after natural warming.”
http://climaterealists.com/index.php?tid=27