This new paper by Kempes et al published in the journal Plos One adds uncertainty to the already uncertain science of dendrochronology dendroclimatology and the attempts at tracking temperature from tree rings. According to this BBC story:
They found that a 2C (3.6F) increase resulted in the average maximum height of trees shrinking by 11%, while a 2C decrease in the nation’s average temperature saw a 13% increase in the predicted maximum height of trees.
Here’s a figure from the paper showing height change with temperature:
The BBC story continues:
“This looks at the basic physics affecting a tree, such as internal fluid flow and the structure of the canopy,” he told BBC News.
“We really wanted something that was based in those mechanisms but at the same time was, conceptually, relatively simple.”
He said tree branches formed a fractal, which meant that if you effectively cut off a branch and then enlarged it, it looked like a whole tree.
“If you nail down that network structure correctly, then you can use it to predict how things change with size.”
From this framework, the team then incorporated local meteorological data, such as rainfall and mean annual temperatures, to allow them to predict the maximum height of trees in the area.
When compared with official data collected by the US Forest Service, the team found that their predictions tied in closely with the actual measurements.
Clearly, there’s more to tree growth than a simple linear relationship with temperature, and this finding shows an inverse relation with temperature to tree height. Maybe this is why Briffa had to truncate uncooperative tree ring data post 1960 and Mike’s Nature trick was used to “hide the decline”.
Here’s the paper abstract, link to the full paper follows.
Predicting Maximum Tree Heights and Other Traits from Allometric Scaling and Resource Limitations
Christopher P. Kempes, Geoffrey B. West, Kelly Crowell, Michelle Girvan
Abstract
Terrestrial vegetation plays a central role in regulating the carbon and water cycles, and adjusting planetary albedo. As such, a clear understanding and accurate characterization of vegetation dynamics is critical to understanding and modeling the broader climate system. Maximum tree height is an important feature of forest vegetation because it is directly related to the overall scale of many ecological and environmental quantities and is an important indicator for understanding several properties of plant communities, including total standing biomass and resource use. We present a model that predicts local maximal tree height across the entire continental United States, in good agreement with data. The model combines scaling laws, which encode the average, base-line behavior of many tree characteristics, with energy budgets constrained by local resource limitations, such as precipitation, temperature and solar radiation. In addition to predicting maximum tree height in an environment, our framework can be extended to predict how other tree traits, such as stomatal density, depend on these resource constraints. Furthermore, it offers predictions for the relationship between height and whole canopy albedo, which is important for understanding the Earth’s radiative budget, a critical component of the climate system. Because our model focuses on dominant features, which are represented by a small set of mechanisms, it can be easily integrated into more complicated ecological or climate models.
Here’s how the model and observations match:
Full paper: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0020551
h/t to WUWT reader “SandyInDerby”
Kev-in-Uk:
Your post at August 8, 2011 at 11:40 am is a classic example of troll misdirection.
My post at August 8, 2011 at 10:41 am pointed out that anybody with two brain cells to rub together must know that tree growth is affected by many variables so cannot indicate temperature. And I said the important issue is:
“But there were people of at least average inteligence who foisted this idea on the world and a countless number who accepted it.
Those who did the foisting and those not ‘intelectually challenged’ who accepted it must have known it was nonsense. But they did it and they got away with it for years.”
But you try to change that into a discussion of how good treemometers are.
This can only mean that you suffer from ‘learning difficulties’ or you are afraid to face the enormity of what was done by Mann, Bradley, Huges, Briffa etc. and their supporters.
Richard
Is the standard of science education so low today that too many science graduates produce work containing ridiculous assumptions? (I have no science background, but sense it from my reading.)
Theo Goodwin says:
August 8, 2011 at 2:48 pm
In short, yes and no! I agree that pretty much all proxy temp data is going to be uncertain. However, when you compare, say, proxy temps from trees to those from ice cores, stalagmites, etc – that is when you may see a correlation which one may infer is most likely due to temperature. Taking one proxy on its own – especially trees, which are affected by numerous other factors such as water, co2, sunlight (e.g. volcanic activity), etc – does not provide a good standalone indicator, and certainly not in any real quantitative manner.
Richard S Courtney says:
August 9, 2011 at 1:58 am
I am not sure I follow your reasoning for asserting I have engaged in some form of classical troll misdirection, and respectfully request that you clarify that assertion.
Moreover, I am perfectly aware of the misdirection of Mann, Briffa, et al – which has been so amply demonstrated as fraudulent ‘science’ subsequently. However, to ‘diss’ tree proxies out of hand because of someone elses fraudulent use is incorrect, in my opinion, and this was the purpose of my post.
As for the insult in implying I have/had troll intentions and subsequent referring to my ‘learning difficulties’, I will let it slide on the reasonable presumption that you jumped the gun and/or I did not make my post clear enough for you. Suffice it to say that I do indeed know how to spell intelligence, and which I note from your post, that you do not! LOL
Richard S Courtney says:
August 9, 2011 at 1:58 am
and just so we are clear, as to who misunderstood who, you said..
My post at August 8, 2011 at 10:41 am pointed out that anybody with two brain cells to rub together must know that tree growth is affected by many variables so cannot indicate temperature.
and hence I am disputing that your categorical dismissal (‘cannot indicate temperature’) as incorrect. I am not disputing the inherent errors and uncertainties, but your simple dismissal is factually incorrect. Tree growth is indeed affected by temperature and this MAY well be able to be extracted from tree growth data. If you are disputing that (which you clearly are with your categoric dismissal), I fear it is yourself with the so called learning difficulties.
As regards your comment that those that foisted the hyper reliance (or reliability) of tree proxy data, and further those that accepted it as reliable – I could not agree more! But that still doesn’t mean tree growth proxy data is useless! (though obviously, in the hands of Mann et al, it certainly has proven to be so!)
Kev from UK and Richard Courtney, stop insulting each other about tree rings. Even the earthworm knows that is better when is more moisture in the ground = better climate = bigger tree rings. Nothing to do with warmer planet or cooler. Same with stalagmites – if is more calcium = faster growth of stalagmites; calcium exhausted = less build up on stalagmites. Then animal bones decay = increase of calcium – has nothing to do with temperature. In the next gully was no dead animal to decay = less calcium for stalagmites and for the trees.
One using tree rings / stalagmites as climate indicator; only shows how low the Warmist can get. Proof that is too much money spent on the Warmist Mafia. Water controls the climate, not CO2. There is no such a thing as GLOBAL warming. If some area gets warmer ( as big city heat) air in the city expands – the extra volume of air goes up – intercepts extra coldness – that extra coldness falls some other place = that other place instantly gets colder = same amount of heat overall in the atmosphere. If your high intelligence can understand that: extra heat in the atmosphere is not accumulative – you will sleep better. You should join forces and blame whoever brainwashed you that carbon is bad; instead insulting each other about some superficial lies. It’s time to stop with the ‘’carbon footprints’’ nonsense and time for ‘’carbon fingerprinting’’ the Warmist opportunist. Plus, you should take them in a class action for ‘’brains degradation’’ I will be your witness. Both of you have being clogging my email with lots of Warmist dysentery for the last few days.
Stefan Mitich says:
August 9, 2011 at 4:18 pm
actually Stefan – I would suggest you are over simplifying – extra calcium for stalagmite formation can occur for a variety of reasons, not least of which one could be acid rain! or more explicitly, increased atmospheric CO2 causing increased acidity in rainfall causing increased dissoluton of calcium carbonate (limestone to you) and thus causing increased stalagmite formation rate, or it could be just increased rainfall, (and I agree – perhaps dead animal bones too) etc, etc………the whole point being that all proxies are necessarily relative – but that the implied ‘relativity’ is not a fixed metric – and anyone that says otherwise is talking out of their rear end! So, with respect, I would suggest you understand the root causes of the formation of stalagmites before you diss them as historical climate indicators either!
FFS – am I talking a different language or what? – proxies are exactly that – fecking proxies and anyone who says they are pure cast iron indicators is a complete moron – they are simply indicators – nothing more, nothing less. But, and this is the major point – if a lot of them show similar trends – and the COMMON variable (between them) is temperature – then it is reasonable to assume that the common link is indeed fecking temperature! FFS – we measure distant planets and their atmospheres based on ‘proxy’ satellite data, etc, etc – it really is not rocket science – but it is still only an indicator – not a proven ‘record’. Is that so difficult to grasp and understand?
BTW – as far as I know – earthworms hate excess moisture in the soil – they tend to come to the surface to avoid drowning, but maybe I didn’t observe that fact correctly!
and another thing – of course, I agree that Global warming is bullsh*t – but don’t diss the basic science that allows proxies – they work for the skeptics too you know! otherwise how would we ‘know’ that CO2 was much higher in the past? it doesnt detract from the fact that proxies are useful and should be properly considered.
and as for Richard – I don’t know – but he seems to be avoiding the thread – perhaps he fails to realise that we are both on the same side? 🙂
Kev-in-Uk says:
August 9, 2011 at 7:18 am
I doubt that we have a disagreement. My one and only point in this matter is that any proxy is affected by several environmental factors. Each of those environmental factors must be understood. To understand them requires doing empirical research that leads to reasonably well confirmed physical hypotheses about the behavior of the proxy. I bet you do not disagree with that.
My point about Briffa and friends is that they found forty years of evidence which screamed “You do not understand the behavior of these tree ring proxies or tree rings are not suitable proxies for temperature.” In either case, empirical research was required. They hid that fact. They did not do the research. They still haven’t done it. Yet they still stand behind their so-called work. Just how bad a scientist can one be?
Incontrovertibly, unambiguously, and tragically yes. The standards for peer-review are in worse shape.
Faye Busch says:
August 9, 2011 at 4:31 am
Incontrovertibly, unambiguously, and tragically yes. The standards for peer-review are in worse shape.
I was answering Faye’s question in my post above.
I suspect the saying about pine cones needing a fire to release its seeds is a myth, but I cannot offer any proof other than to say that little pine trees spring up on my property where no fires have burned. Also, the old dried pine cones littering a forest floor are turned into nothing but ash during a fire. I use pine cones to start the fire in my wood stove, and where I dump the ashes from the wood stove, no little pine trees have sprouted.
Kev- in UK (and others):
The fact is
anybody with any sense,
anybody with a garden, and
anybody who had owned a pot plant,
must have known TREEMOMETERS CANNOT WORK.
And when an attempt to use trees as thermometers was made THEY DID NOT WORK
(hide the decline).
The issue is NOT whether treemometers are useful: they are not.
Kev, trees are not useful proxies for temperature: they cannot be.
Specious arguments about whether treemometers work obscure the issues.
The issues are
1.
Mann, Hughes, Bradley, Briffa, et al. knowingly and with clear malice of forethought
PRETENDED TREEMOMETERS WORK.
2.
Others accepted the daft assertiion that treemometers work.
3.
There are still people who cling to the daft idea that treemometers work.
And I have no patience with apologists for Mann, Hughes, Bradley, Briffa, et al.
Richard
Theo Goodwin says:
August 9, 2011 at 5:56 pm
agreed entirely…
@richard, I have not noted anyone defending Mann et al (and I don’t frequent RC, which is no doubt where any support would come from). The fact I am defending a proxy as of potential use (with the usual caveats over uncertainty) does not mean I am defending anything Mann et al have done. Aux contraire, I am very dismayed by their so called science in this regard.
I still consider my point to be valid, namely that proxies, especially in combination, do have some merit – and without them, we really cannot say much about any past climate that wasn’t written down and recorded in ways directly transferable to a measurement/mmetric of today!
In the context of say, the MWP, which is only really inferred from various proxies (and a few historicval ‘notes’) – and the reliance of the MWP as an indicator of past warmer climes and therefore making the current alleged warming less important – we, as skeptics must surely accept this information. If you don’t want to accept proxies per se, then we are in a real pickle – having to rely on manipulated surface station data and other observations held by our esteemed climate science bodies ! (Note – I am being sarcastic there!)
Currently, I’m sure nobody here would like to have to rely solely on such records? and thus, what choice do we have but to use all available proxies as generic ‘indicators’? As a scientist, and a skeptic – I will look at any and all available data and use/discard it according to its individual merit – Short of the Doc from Back to the Future, appearing in his shiny Delorean and whisking us off to past times – what other choice do we have?
Kev-in-Uk:
You say at August 10, 2011 at 7:50 am you say to me:
“The fact I am defending a proxy as of potential use (with the usual caveats over uncertainty) does not mean I am defending anything Mann et al have done.”
That is a ‘non sequitor’.
The proxy in question is treemometers. It was a ridiculous stretch to think or imagine treemometers could work, and when tried they did not. Mann et al. pretended treemometers did work.
So, when you defend treemometers as “a proxy as of potential use” then you ARE defending what Mann et al. did.
And you say to me:
“If you don’t want to accept proxies per se, then we are in a real pickle …”
That is a ‘straw man’.
The fact that treemometers are useless says nothing about the usefulness of other proxies for determination of past temperatures. Your assertion is akin to saying;
“If you say tomatoes cannot be used to make chairs then you are doubting that wood can be made into chairs”.
Richard