More bad news for Mann and Briffa

Seems like every day there is more bad news for the fans of the hockey stick. 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

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0020551

pretty easy read. the math is tolerable

 

We've known this for a long time the psychotics just refused to admit it. There is no evidence that trees have a strictly linear relationship to temperature. If there is an optimum temperature for trees than any reconstruction will cap and you will not get a valid representation of previous warm periods. Then when you compare apples and oranges by comparing instrumental records to the reconstruction you will be fooled into saying that 'the present warm period is greater than any time in the past 2000 years.'

The null hypothesis when the divergence problem began to manifest should have been that trees have an optimum temperature and do not respond to temperature linearly. Instead the hacks went ahead and called it bad data caused by some anthropogenic factor with absolutely no evidence to support that claim and without ever addressing the null hypothesis.

 

LOLOLOLOL......you deniers are soooo funny and soooooooooo delusional. The paper you cite doesn't say anything at all about tree rings or the use of tree rings as proxy data in paleoclimate reconstructions. The paper is totally unrelated to the causes of global warming. It most certainly does not mean "More bad news for Mann and Briffa", as you so foolishly imagine.

But the fact that both you and windy seem to imagine that the tree ring proxy data is the only source of information that scientists use to reconstruct past climates just demonstrates how shallow your knowledge of this subject actually is. The fact that all of the different proxies show about the same past climate patterns is a fact you would rather ignore than deal with.

Here's the range of data sources that the climate scientists actually use to reconstruct past climates.

A Paleo Perspective on Global Warming
NOAA Paleoclimatology

Proxy Data

Proxy data is data that paleoclimatologists gather from natural recorders of climate variability, e.g., tree rings, ice cores, fossil pollen, ocean sediments, coral and historical data. By analyzing records taken from these and other proxy sources, scientists can extend our understanding of climate far beyond the 140 year instrumental record.

Listed below are some widely used proxy climate data types:

Historical Data:
Historical documents contain a wealth of information about past climates. Observations of weather and climatic conditions can be found in farmers' logs, travellers' diaries, newspaper accounts, and other written records. When properly evaluated, historical data can yield both qualitative and quantitative information about past climate.

The example above demonstrates how historical grape harvest dates were used to reconstruct summer temperatures (April - September) in Paris from 1370 - 1879. [From Bradley, 1990; based on data Le Roy Ladurie and Baulant, 1980.]


Corals:
Corals build their hard skeletons from calcium carbonate, a mineral extracted from sea water. The carbonate contains oxygen and the isotopes of oxygen, as well as trace metals, that can be used to determine the temperature of the water in which the coral grew. These temperature recordings can then be used to reconstruct climate during that period of time that the coral lived.

To learn more about the study of corals please visit

* NOAA's Coral Paleoclimatology Site.


Fossil Pollen:
Each species and genus of plants produces pollen grains which have a distinct shape. These shapes can be used to identify the type of plant from which they came. Since pollen grains are well preserved in the sediment layers that form in the bottom of a pond, lake or ocean, an analysis of the pollen grains in each layer tell us what kinds of plants were growing at the time the sediment was deposited. Inferences can then be made about the climate based on the types of plants found in each layer.

To learn more about fossil pollen, please visit the following:

* Institute of Paleontology, University of Vienna, Austria
* Fossil Groups: Spores and Pollens, U.S. Geological Survey (USGS)


Tree Rings:
Since tree growth is influenced by climatic conditions, patterns in tree-ring widths, density, and isotopic composition reflect variations in climate. In temperate regions where there is a distinct growing season, trees generally produce one ring a year, and thus record the climatic conditions of each year. Trees can grow to be hundreds to thousands of years old and can contain annually-resolved records of climate for centuries to millennia.

To learn more about tree rings please visit the following:

* Laboratory of Tree Ring Research at the University of Arizona
* "Ultimate Tree-Ring Web Pages", University of Tennessee


Ice Cores:
Located high in mountains and deep in polar ice caps, ice has accumulated from snowfall over many centuries. Scientists drill through the deep ice to collect ice cores. These cores contain dust, air bubbles, or isotopes of oxygen, that can be used to interpret the past climate of that area.

To learn more about ice cores please visit the following sites: The Australian Antarctic Division

* The American Geophysical Union
* Greenland Ice Cores Summit (GISP2) Project


Ocean & Lake Sediments:
Between 6 and 11 billion metric tons of sediment accumulate in the ocean and lake basins each year. Scientists drill cores of sediment from the basin floors. Ocean and lake sediments consist of materials that were produced in the lake/ocean or that washed in from nearby land. These materials (preserved tiny fossils and chemicals in the sediments) can be used to interpret past climate.

To learn more about ocean and lake sediments, please visit the following:

* Ocean Drilling Program
* International Marine Global Changes Study
* News Article, "History on the Bottom of the Lake", written by Leo Poppoff, a retired NASA atmospheric physicist and a former member of the Lahontan Water Quality Control Board

 

whether you want to admit it or not LF , but another wheel just came off you buddies bus

 

Livefree's argument only makes some sense to the people who dont know the issue. While the Manns and Briffas of the world may talk about all the proxies that they use time and time again it has been proven that their reconstructions get their shapes from just a few proxies in the entire series. This is because the method inherently mines for hockey sticks(Burger, Cubasch, GRL 2005). For Dr. Mann his first reconstruction relied 100% on the presence of the graybill series of bristlecone pines from Colorado. Dr. Manns later reconstruction relied 100% on the same pines and a bogus lake sediment that he turned upside down, the lake sediment actually showed a strong medieval warm period but by turning it upside down Dr. Mann was able to make the medieval warm period look like an ice age and the little ice age look like warming, hello super hockey stick. In the case of Briffa's reconstruction, the thing relies on one tree. Yes I said that correctly. The entire shape of his reconstruction is dependent on one tree in Siberia cataloged as YADO61. Dr. Briffa got much heat from that "mistake". It is quite clearr from the Climategate e-mails the good Dr. was neverat ease with the science he and the team were engaging in and the political pressure that they were under to present a nice neat package. I think that is what led him to leak the Climategate e-mails.

 

Total horseshyt and debunked denier cult myths. Wrong in pretty much every detail. Windy's denier cult myths only make some sense to people who know absolutely nothing about this. The hockey stick graph has been independently reproduced by many other groups of scientists using a wide variety of proxy data from all of the sources listed in that NOAA article I just cited. BTW windy, Briffa's reconstruction was based on 'one species of tree', not "one tree". LOL.

Surface Temperature Reconstructions for the Last 2,000 Years
Authors: Committee on Surface Temperature Reconstructions for the Last 2,000 Years, National Research Council

In response to a request from Congress, Surface Temperature Reconstructions for the Last 2,000 Years assesses the state of scientific efforts to reconstruct surface temperature records for Earth during approximately the last 2,000 years and the implications of these efforts for our understanding of global climate change. Because widespread, reliable temperature records are available only for the last 150 years, scientists estimate temperatures in the more distant past by analyzing "proxy evidence," which includes tree rings, corals, ocean and lake sediments, cave deposits, ice cores, boreholes, and glaciers. Starting in the late 1990s, scientists began using sophisticated methods to combine proxy evidence from many different locations in an effort to estimate surface temperature changes during the last few hundred to few thousand years. This book is an important resource in helping to understand the intricacies of global climate change.


FIGURE S-1 Smoothed reconstructions of large-scale (Northern Hemisphere mean or global mean) surface temperature variations from six different research teams are shown along with the instrumental record of global mean surface temperature. Each curve portrays a somewhat different history of temperature variations and is subject to a somewhat different set of uncertainties that generally increase going backward in time (as indicated by the gray shading). This set of reconstructions conveys a qualitatively consistent picture of temperature changes over the last 1,100 years and especially over the last 400. See Figure O-5 for details about each curve.


***

Hockey stick controversy
From Wikipedia, the free encyclopedia
(excerpts)

More than twelve subsequent scientific papers, using various statistical methods and combinations of proxy records, produced reconstructions broadly similar to the original MBH hockey-stick graph, with variations in how flat the pre-20th century "shaft" appears. Almost all of them supported the IPCC conclusion that the warmest decade in 1000 years was probably that at the end of the 20th century.[6]

A study by Anders Moberg et al. published on 10 February 2005 used a wavelet transform technique to reconstruct Northern Hemisphere temperatures over the last 2,000 years, combining low-resolution proxy data such as lake and ocean sediments for century-scale or longer changes, with tree ring proxies only used for annual to decadal resolution. They found there had been a peak of temperatures around AD 1000 to 1100 similar to those reached in the years before 1990,[68] and supported the basic conclusion of MBH99 by stating "We find no evidence for any earlier periods in the last two millennia with warmer conditions than the post-1990 period".[65][69]

In May the University Corporation for Atmospheric Research advised media about a detailed analysis by Eugene Wahl and Caspar Ammann, first presented at the American Geophysical Union’s December 2004 meeting in San Francisco, which used their own code to replicate the MBH results, and found the MBH method to be robust even with modifications. Their work contradicted the claims by McIntyre and McKitrick about high 15th century global temperatures and allegations of methodological bias towards a hockey stick outcomes, and they concluded that the criticisms of the hockey stick graph were groundless.[79]

At the American Statistical Association 2006 Joint Statistical Meetings, John Michael Wallace reported that the NRC had found the Mann et al. claim that the last two decades were the warmest of the last 1000 years "entirely plausible", supported by a wide range of evidence. They had reported this cautiously, as "plausible" meaning 2:1 odds in favor.[117]

In a paper published by PNAS on 9 September 2008, Mann and colleagues produced updated reconstructions of Earth surface temperature for the past two millennia.[140] This reconstruction used a more diverse dataset that was significantly larger than the original tree-ring study, at more than 1,200 proxy records. They used two complementary methods, both of which showed a similar "hockey stick" graph with recent increases in northern hemisphere surface temperature are anomalous relative to at least the past 1300 years. Mann said, "Ten years ago, the availability of data became quite sparse by the time you got back to 1,000 AD, and what we had then was weighted towards tree-ring data; but now you can go back 1,300 years without using tree-ring data at all and still get a verifiable conclusion."[141] In a PNAS response, McIntyre and McKitrick said that they perceived a number of problems, including that Mann et al used some data with the axes upside down.[142] Mann et al. replied that McIntyre and McKitrick "raise no valid issues regarding our paper" and the "claim that 'upside down' data were used is bizarre", as the methods "are insensitive to the sign of predictors." They also said that excluding the contentious datasets has little effect on the result.[143]

A study of the changing climate of the Arctic over the last 2,000 years, by an international consortium led by Darrell Kaufman of Northern Arizona University, was published on 4 September 2009. They examined sediment core records from 14 Arctic lakes, supported by tree ring and ice core records. Their findings showed a long term cooling trend consistent with cycles in the Earth's orbit which would be expected to continue for a further 4,000 years but had been reversed in the 20th century by a sudden rise attributed to greenhouse gas emissions. The decline had continued through the Medieval period and the Little Ice Age. The most recent decade, 1999–2008, was the warmest of the period, and four of the five warmest decades occurred between 1950 and 2000. Scientific American described the graph as largely replicating "the so-called 'hockey stick,' a previous reconstruction".[144]

Further support for the "hockey stick" graph came from a new method of analysis developed by Martin Tingley and Peter Huybers of Harvard University, which produced the same basic shape, albeit with more variability in the past, and found the 1990s to have been the warmest decade in the 600 year period the study covered.[145]

 

No surprise...there's nothing in the cited study that supports your contention. Why not post the idiotic Anthony Watts post you parroted that drivel from? Don't pretend you found this study and reached that stupid conclusion on your own.

An apt and notable conclusion from the study would be that timber yields may decline with warmer temperatures.

http://www.bbc.co.uk/news/science-environment-14250825

 

False.

False.

False.

You obviously do not understand what this graph plainly says, which is that the Mann hockey stick has been refuted.

Nobody denies that temperatures have increased substantially since the Little Ice Age. That was never the point of the hockey stick. The distinctive frauds of the Mann hockey stick graph were its portrayal of a largely unchanging climate (a slight and near-linear decline from the MWP to the LIA) until the 20th C, and its commingling of different data sets over different periods. The above graph still commits the latter epistemological sin, but clearly refutes the Mann hockey stick on the former. Of the seven temperature records graphed, only three extend back to the MWP, and of those three, two show that the peak of the MWP was warmer than the 1990s. The lone dissenting record, which more closely recapitulates the Mann hockey stick is -- surprise, surprise -- a reconstruction by two of the biggest AGW fraudsters, Phil Jones and Mann himself. In addition, even the temperature reconstructions that don't go back to the MWP clearly show temperatures establishing an up-trend by the early 18th C, again refuting Mann's contention that temperatures did not begin to increase until CO2 became a significant influence in the 20th C.

The claim that this graph "independently reproduces" the Mann hockey stick is a flat-out fabrication. Another fraudulent Mann temperature reconstruction is not an independent confirmation, and the truly independent parts of the graph plainly show that late 20th C was no warmer than the peak of the MWP.

That seems to be a bizarre non sequitur.

 

You arguments get more desperate you go right into a irrelevant ad hom. At least when I post pictures of Dr. Hansen getting taken away in handcuff ... twice ... it has relevance to the integrity of his research. Honestly how do you sleep at night?

Can you really be so obtuse. Dendroclimatology uses the width and density of tree rings, in other words their rate of growth, to determine past temperatures. All tree ring proxies assume a linear relationship with temperature. The warmer the temperature the faster the tree will grow. If the rate of growth is parabolic with a central optimum rather than linear then tree rings are not only hard to use as a proxy they are down right useless because there is no way to tell exactly which side of the parabola you are on.

Reconstructions will reach a maximum temperature at which point they will show a spurious cooling once we pass the optimum. Which is exactly what the present shows and why we have the divergence problem. That you cannot see this tells me that while you may be able to read your favorite blogs run by unemployed cartoonists, see relevant ad hom, you don’t really understand the science. If this study is correct than tree rings can never be and were never a valid temperature proxy.

This all goes back of course to hiding the decline. The hacks were never able to explain the divergence problem so they hid it calling it bad data. The above research shows that it isn't bad data, if there ever was such a thing, but a bad approach from the start as the initial assumption that tree rings can be used as a temperature proxy was false.

 

You are right on that part. Dr. Mann is telling a half truth the methods "are insensitive to the sign of predictors." But that is not a good thing. The methods are flawed. The methods are what turned the graph upside down. The methods are a Helen Keller approach to science, deaf and blind. We've been over this before but live free with his cut and past approach to debating will continue to make the same flawed arguments because they are not his arguments. He doesn't understand what he is copying and pasting.

Once again for all of you that missed it. The tiljander lake sediment is a temperature proxy from a lake in Finland. This is a snow fed lake so the Theory holds that the more snow fall you have, the more summer runoff you have and the denser the sediment pack. So the density of the sediment is inversely corelates to temperature. The more sediment the colder the winter was.

Now Tiljander is a person, the person who gathered the chorology. Tiljander found that starting at the last 18th century human activities had polluted the chronology, in other words human activates farming, dams etc. had led to an artificial increase in lake sediment so the chorology wasn't to be considered valid from the 19th century on but could still be used to reconstruct temperatures pre 19th century. And this was done. Tiljander found the strong presence of the medieval warm period and the little ice age examining the density of the lake sediment.

Now fast forward to when Dr. Mann gets his hands on this proxy. Did he read Tiljander's warning about the 18th century on data? Dont know but he should have because his computer sure as hell cant. His method, the one that doesn't care about sign doesn't know exactly how the proxies it is looking at are supposed to respond to temperature. It is looking for correlation and that is all. If its spurious correlation it doesn't care. It will assume that said spurious correlation is real and will weight the proxy accordingly.

So when the Tiljander chorology was fed into ot the computer the computer went about seeing how it correlated to 20th century temperature. But if we remember Tiljander's warning the 20th century data was corrupted. But the computer didn't know that. It saw the sharp up turn in density in the 20th century and concluded that density positively correlates with temperature, which is ass backwards from the science. This positive correlation calculated by the computer turned the proxy upside down. As I said in the beginning the method was flawed it wrongly assumed that there wouldn't be any spurious correlations. Like the one caused by human activity in the Tiljander chorology.
By turning the proxy upside down the medieval warm period found by Tiljander became an ice age and the little ice age became a warming period. This makes the proxy a super hockey stick.

 

No. Peacefully protesting this type of criminal atrocity on his own time



is extremely brave and honorable. You deniers could learn something about that.

What's not honorable for a scientists is believing that it's your job (not just something you do in your spare time) to enforce a far right political agenda.

Roy Spencer:

That is absolutely disgraceful in fact. Spencer is a politician pretending to be a scientist, and the fact that he's your go-to-guy is revealing.

Why don't you contact the authors of that study and run by that interpretation, then try not to feel so bad when they laugh at you. You'd think deniers would find it a least a little bit odd that their cult leaders never contact the actual scientists behind the studies they mangle. The only thing new the study indicates, as the authors state, is that global warming could reduce timber harvests.

What's funny is deniers pretending to discover something climate scientists already know, that there can be other influences on tree growth and that those evil scientists must never take that into account.

Yawwwnnn....

http://www.skepticalscience.com/Hockey-stick-divergence-problem.html

Studies using tree ring proxies (with and without the modern divergence) and non-tree-ring proxies all come to the same conclusion - that temperatures in recent decades are unprecedented for a millenium or more. Deniers can't seem to escape that conclusion.

 

So you just run into another ad hom on Spencer who wasn't even a topic of discussion until you made him so. You are so pathetic.

In other news it seems that teh IGO's investigation is beginning to make more sense. It appears that the IGO suspects Monett of using his control over public funds to bribe his peer reviewer on the paper in question. Since one of the other reviewers is known to have been his wife this gives him 2 of what is usually 3 in his pocket. Normally you only need 2 of the three to be published.

In the interview Monett tried to place a lot of the blame for the shoddy statistics in the paper on the failure of the peer reviewers to catch it.

Monett's statists amount to this. He claimed that since they claimed to have seen 3 or 4 downed polar bears, mind you then never landed to see how the polar bears supposedly died, and they only surveyed 11% of the area, they concluded that about 36 polar had bears died. This is the first time that they or any one else had ever even seen an allegedly drowned polar bear and none have been seen since. It was a truly rare occurrence.

Now lets examine how stupid this is. Lets say you are walking down a street in New York and find a $100 bill. Now that is a truly rare occurrence. Your first inclination is to survey your field of vision and see if there is any more money. You are able to quickly survey about 10,000sqft and find no more money. You then concluded based on your analysis that there is a $100 bill every 10,000sqft within the city of New York. Therefore, there is $85,000,000 in $100 bills just lying on the street in New York. If your field of vision was limited to 1,000sqft that would mean that there is $850,000,000. The less you are able to survey the more there is. Its like magic.

Now we would all call this preposterous and rightfully so. But if you wrote a scientific paper with this analysis and were boinking on of your peer reviewers and had bribed another you stand a good chance of getting published.

 

From someone who first leveled an ad hom at Dr. James Hansen, routinely posts the same deragatory ad hom photos of him in random fashion, then diverges to the completely different topic of an MMS researcher being muzzled, I find this incredibly funny, and pathetically hypocritical too.

 

I used my ad hom's of Hansen as a quick example of an apt ad hom. I didn't spend an entire post on it. You went off on an unrelated copy and paste ad hom because you are desperate.

And no I'm not interested in John Cooks analysis. This study shows why tree ring growth has declined, warmer temperatures. If as the study claims warmer temperatures past a certain point lead to a decline in growth then tree ring analysis with the present linear relationship assumption is bogus. This isn’t' speculative like every last thing John Cook posted. Now you are demanding that I contact the authors. You are so (*)(*)(*)(*)ing funny. You will stoop to any low.

 

Why is this silly failed thread still going?

As I said before: "The paper you cite doesn't say anything at all about tree rings or the use of tree rings as proxy data in paleoclimate reconstructions. The paper is totally unrelated to the causes of global warming. It most certainly does not mean "More bad news for Mann and Briffa", as you so foolishly imagine."

The claims made about what this paper says are false. Read the paper for yourself if you don't believe me.

This thread is just another example of the futile and stupid 'grasping at straws in a flood' tactic of the denier cultists as the planet continues to warm, the climate patterns continue to change and their cult of denial slides into the trashcan of history alongside the 'flat earth society'.

 

It doesn't have to address dendroclimatology directly. It simply states that at warmer temperatures past a certian point tree growth slows. That contradicts the linear relationship that dendroclimatologists apply to tree growth vs. temperature. If the relationship is parabolic rather than linear with an optimum occurring somewhere in the middle then tree rings are not valid temperature proxies.

As to the human copy and paste maching talking about flood tactic ... lol. You are so funny.

 

You're still just grasping at straws and trying to insert your own twisted interpretations onto a paper that has nothing to do with the claims made in the OP.

 

any paper on Dendrochronology should start once upon a time

seriosuly there are many factors which occur that affect tree growth besides temps. The kids here just need to admit that it is bad science to and move on. Of course libs seem to want to keep things simple and unscientific...go figure

 

It is amusing to hear such ignorant criticisms of science coming from an anti-science denier cultist who is so very clueless about it all.

"There are many factors which occur that affect tree growth besides temps" and the scientists who study dendrochronology are quite aware of them, contrary to your ignorant assumptions.

Dendrochronology
From Wikipedia, the free encyclopedia
(excerpts)

In areas where the climate is reasonably predictable, trees develop annual rings of different properties depending on weather, rain, temperature, soil pH, plant nutrition, CO2 concentration, etc. in different years. These variations may be used to infer past climate variations.

To eliminate individual variations in tree ring growth, dendrochronologists take the smoothed average of the tree ring widths of multiple tree samples to build up a ring history. This process is termed replication. A tree ring history whose beginning and end dates are not known is called a floating chronology. It can be anchored by cross-matching a section against another chronology (tree ring history) whose dates are known. Fully anchored chronologies which extend back more than 11,000 years exist for river oak trees from South Germany (from the Main and Rhine rivers) and pine from Northern Ireland.[3][4][5] Furthermore, the mutual consistency of these two independent dendrochronological sequences has been confirmed by comparing their radiocarbon and dendrochronological ages.[6] Another fully anchored chronology which extends back 8500 years exists for the bristlecone pine in the Southwest US (White Mountains of California).[7] In 2004 a new calibration curve INTCAL04 was internationally ratified for calibrated dates back to 26,000 Before Present (BP) based on an agreed worldwide data set of trees and marine sediments.[8]

 

You haven't contradicted my interpenetration, you have just called it names.

 

You admit that it is your interpretation (or your copying of jackdog's). Your interpretation is yours, not that of the scientists who wrote the paper cited in the OP. You have so far on this forum never given any signs that you have the education, intellect or competence to render even remotely accurate 'interpretations' of the work of actual scientists. In fact, most of your 'interpretations' are wildly wrong and not even really yours. You just parrot whatever spin or BS that you scraped off of some denier cult blog. Or in this case you parroted Jackdog who started the thread copying and pasting directly from well known denier cult nutjob and fraud Anthony Watts and pretending he was saying it himself. BTW, I thought it was a requirement on this forum that you make some personal comment yourself and not just start a thread with an almost total C&P. You can look at the OP and here is the unattributed direct quote from the denier cult blog WattsUpMyButt that comprises most of the OP..

"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.

 

Dendrology is an academic name for forestry, isn't it?

 

Roy - you are wrong here in several ways.

First - the medieval warm period was regional, what we're seeing now is global. Not the same thing.

Second - there indeed have been multiple independent from Mann studies that used different data that all confirmed what Mann's work showed. Going after Mann misses the point

 

No, I am objectively correct. Don't be ridiculous.

Garbage. We already know that AGW fraudsters have undertaken a deliberate and organized disinformation campaign to "get rid of the Medieval Warm Period." Cherry-picking data to show the MWP was regional does not make it regional.

That is a flat-out fabrication, as I already proved. Mann's original hockey stick graph showed no MWP, no LIA, and no increase in temperature before the 20th C. All three have been conclusively disproved by subsequent independent studies, which together show a more wave-like variation in temperature, with a pronounced MWP and LIA, and temperature increases starting in the 18th C, well before CO2 could possibly have been a significant contributing factor. AGW fraudsters just look at data that prove Mann wrong and claim they confirm Mann's conclusions!

 

No citations = you are just making crap up.

Show the citations if you are correct - and they need to be real science - not drivel from Watt and the usual denier sources.

If you are "objectively correct" this will be easy to do. If you cannot provide real science - not drivel from Watt and the usual denier sources - then you have confirmed you are just making crap up.