Dendrochronology - Another inconvenient truth for Profit Gore
Tunderbar
A Little Secret
By Steve McIntyre
Don't you think that someone on the Team might have been a little
curious as to what bristlecone ring widths have done during the past
25 years? For this, we have the classic excuse of Michael Mann and the
Team for not updating bristlecone and proxy records is that it's not
practical within the limited climate budgets:
While paleoclimatologists are attempting to update many important
proxy records to the present, this is a costly, and labor-intensive
activity, often requiring expensive field campaigns that involve
traveling with heavy equipment to difficult-to-reach locations (such
as high-elevation or remote polar sites). For historical reasons, many
of the important records were obtained in the 1970s and 1980s and have
yet to be updated.
>From the first moment that I got involved with paleoclimate, it seemed
obvious to me (as it is to anyone not on the Team) that, if the
classic "proxies" are any good and not merely opportunistic
correlations, that there is an ideal opportunity to perform out-of-
sample testing of the canonical Team reconstructions by bringing the
proxies up-to-date. I wrote an Op Ed in February 2005 for the National
Post entitled "Bring the Proxies Up to Date", where I expressed the
view that this was really the first order of business in Team world.
While the addition of new proxies is also important and nice, this is
not the same thing as out-of-sample testing of the proxies used in
MBH99, Crowley and Lowery etc - especially the bristlecones.
I've continued to satirize this failure pointing out that several of
Graybill's classic bristlecone sites were easily accessible from UCAR
world headquarters in Boulder and that no heroic expedition was
required to update, for example, the Graybill sites to the west of
Colorado Springs.
To get to these sites from UCAR headquarters in Boulder, a scientist
would not merely have to go 15 miles SW of Colorado Springs and go at
least several miles along a road where they would have to be on guard
for hikers and beware of scenic views, they would, in addition, have
to go all the way from Boulder to Colorado Springs. While lattes would
doubtless be available to UCAR scientists in Colorado Springs, special
arrangements would be required for latte service at Frosty Park,
though perhaps a local outfitting company would be equal to the
challenge. Clearly updating these proxies is only for the brave of
heart and would require a massive expansion of present paleoclimate
budgets. No wonder paleoclimate scientists have been unable to update
these records since Graybill's heroic expedition in 1983.
Pete Holzman (Mr Pete), who lives in Colorado Springs, agreed with
this satire and this led to what I'll call the Starbucks Hypothesis:
could a climate scientist have a Starbucks in the morning, collect
tree rings through the day and still be home for dinner?
To make a long story short, last summer, when my wife and I visited my
sister in Colorado Springs and I thought that it would be rather fun
to test the Starbucks Hypothesis and I gave a bit of a teaser report
in late July, promising some further reports in a few weeks, but I got
distracted by the Hansen stuff. At the time, I mentioned that,
together with CA reader Pete Holzmann and his wife Leslie, we visited
some bristlecones in the Mt Almagre area west of Colorado Springs.
But I have a little secret which I'll share with you as long as you
promise not to tell anyone: our objective was to locate the precise
site sampled by Graybill. Not just that. Prior to the trip, I obtained
a permit from the U.S. Forest Service to take dendrochronological
samples from bristlecones on Mount Almagre and we did more than look
at pretty views; we obtained up-to-date bristlecone samples. I only
went up Almagre on the first day. Our permit lasted a month and Pete
and Leslie spent two more days on Almagre, finally locating and
sampling tagged Graybill trees on the third day.
Altogether (and primarily through the efforts of Pete and Leslie), our
project collected 64 cores from 45 different trees at 5 different
locations on Mount Almagre. 17 Graybill trees were identified, of
which 9 were re-sampled. All the cores are currently at a
dendrochronological laboratory, where sample preparation and scanning
steps have been completed. Cross-dating is now taking place. For the
most part, we tried to sample non-stripbark trees in keeping with NRC
recommendations, but some stripbarks were sampled to reconcile with
Graybill.
We will archive at WDCP detailed information on the location of all
samples (current spreadsheet is here) , which has already been sent to
the U.S. Forest Service. Photographs of each tree are shown gallery
here.
Some expenses have been incurred for this expedition. Leaving aside
travel expenses (which were vacation expenses that I was going to
incur anyway), the jeep got a bad scratch on the first day and cost
about $500 to repair; it's going to cost a few thousand at the
dendrochronology laboratory for the sample prep, scanning and cross-
dating as this has been done on a contract basis. I've submitted an
abstract to Rob Wilson's divergence session at AGU and would like to
present these results (and to cover Pete's expenses if he can come).
This has been a Climate Audit project so I'd like readers who
contribute to the top jar to think about a special contribution for
the bristlecone sampling. Maybe Martin Juckes, James Hansen and
Michael Mann will contribute as well - I'm sure that they are all
anxious for the results.
I'll add some more information later in the day. Right now I'm off to
visit the dendro lab and see how things are coming along. In 2002,
Malcolm Hughes sampled bristlecones at Sheep Mountain and nothing has
been reported or archived from this study. In 2003, Lonnie Thompson
sampled ice cores at Bona-Churchill and we've heard nothing about it.
One might guess that 20th century dO18 levels were not high as, at the
nearby site of Mount Logan, 20th century dO18 levels were lower than
earlier levels, attributed to regional changes in circulation rather
than temperature.
I've obviously been very critical of what appears to be opportunistic
reporting of results. With my experience in mining speculations, I
fully understand how much temptation that there is to delay reporting
of "bad" results in the hope that later drill holes in the program
will salvage things. But you don't have any choice in the matter -
you're obliged to report the results. Plus investors are smart enough
to now that delayed results are virtually never good results.
Right now I have no idea what the sampling will show - maybe it will
show a tremendous response by the bristlecones in the past 20 years -
perhaps due to CO2, nitrate or phosphate fertilization, perhaps due to
temperature increases. Maybe they won't go up and we'll hear more
about the divergence problem. I don't expect these particular
measurements to settle anything. But jeez, doncha think that someone
would have tried to find out?
Anyway I promise one thing: the measurements are going to be made
public as soon as I get them. Just like a mining project. No waiting
for 5 or 10 or 25 years like certain people. No losing the data like
other people. Whatever they show. As soon as I get the cross-dated
measurement data, we will immediately send it to the World Data Center
for Paleoclimatology (which I expect to take place within a few
weeks.) I hope that this will set an example to the trade as to the
type of turn-time which is practical.
I'm visiting the dendro lab today to say hello and I wanted this to be
on the record before my visit. I'm not sure how far along they are,
but I think that they've finished sample prep and scanning and have
started cross-dating. I don't expect any results, but they may be far
along enough so that I'll have an impression of what the result growth
will have been. So I wanted to be on the record on the planned
schedule prior to my knowing anything about the results, just in case
I get an impression today of what the recent growth has been.
UPDATE 2 pm. OK, I'm back from the dendro lab in Guelph. They are
further along than I expected. The longest core is 883 years (Tree 30A
http://picasaweb.google.com/Almagre.Bristlecones.2007/2AlmagreTrees ).
This had a Graybill tag 84-55, but if you go to the archived
measurement data
and look for ALM55 (which would presumably be the match), there are no
corresponding measurements; there is obviously a sequence ALM01, ....;
there is an ALM53 and an ALM60. Is there an alter ego somewhere or is
it missing? Right now we don't know.
After sanding the core is scanned. The measurement of ring widths is
semi-automatic. For these bristlecones, earlywood and latewood was
easy to distinguish. Using a magnified version of the scan, each ring
is picked out (with the computer recording the pick). The computer
then yields back the measurements. I've posted up a couple of print-
screens showing the most recent widths for 30A and the widths in the
mid-19th century.
.
Below is a print screen showing the 30A ring widths from 1124 to 2007.
I'll post up a re-plot at some point with a legible x-axis. For
orientation in the absence of a scale, the upspike on the left is
1174; there are low values from 1353 through the early 1400s; there is
a 1690 spike; 1865 and 1880 are upspikes; 1941 is a small upspike.
According to the Team hypothesis of a positive linear relationship
between temperature and ring widths, the warm 1990s and 2000s should
have yielded the widest ring widths in history. What do you think?
This is only one tree, but my quick impression was that recent growth
was not elevated. So this looks like a Divergence "Problem". If CO2 or
other fertilization has been a factor, then I hate to think what the
growth would have been without the fertilization. Remember the NAS
panel saying that the Divergence Problem only affected high-latitude
sites? Maybe they should have done some testing before they opined on
this.
BTW while I'm critical of how the Team uses dendro information, I
think that it is well worth supporting the collection of dendro
information, even if it's meaning is not clear right now. It has the
advantage of being well-dated - and when you see the problems with
dating ocean sediments, it's nice to have some records that are well
dated. There's a role for it; so please - no posts dumping on
dendrochronology. The dendrochronologists who've been doing this work
(and who I will credit in due course) are excellent people.
****
Check out the chart!!!!!!
Tunderbar
Heaven forbid we let the science contradict the propaganda.