Comments on: The Barton Letters http://cstpr.colorado.edu/prometheus/?p=3511 Wed, 29 Jul 2009 22:36:51 -0600 http://wordpress.org/?v=2.9.1 hourly 1 By: Ed Snack http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1251 Ed Snack Wed, 06 Jul 2005 01:09:02 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1251 Eli, "so what parts are missing", well, the code is only for the PC tree ring calculations. I urge you to check it yourself. If that was all there was to MBH98, then, yes, we would have it all. However, once you have the PCs, you do need to go a bit further to produce a temperature reconstruction, and so far, the descriptions of the algorithms and methods used in that reconstruction do not permit a complete emulation. Hence the request for the code. You later state "I also am less than impressed with McIntyre's mathematical skills." Would you care to elaborate and perhaps provide corrections as appropriate ? Would you also like to defend the inclusion of the Bristlecone Pine records in MBH98, given that the growth of those trees is manifestly not responding to temperature ? Eli, “so what parts are missing”, well, the code is only for the PC tree ring calculations. I urge you to check it yourself. If that was all there was to MBH98, then, yes, we would have it all. However, once you have the PCs, you do need to go a bit further to produce a temperature reconstruction, and so far, the descriptions of the algorithms and methods used in that reconstruction do not permit a complete emulation. Hence the request for the code.

You later state “I also am less than impressed with McIntyre’s mathematical skills.” Would you care to elaborate and perhaps provide corrections as appropriate ?

Would you also like to defend the inclusion of the Bristlecone Pine records in MBH98, given that the growth of those trees is manifestly not responding to temperature ?

]]> By: per http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1250 per Sun, 03 Jul 2005 11:18:02 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1250 implications ? or a scientific paper ? your talk of guess-work as a means to scientific replication makes clear your approach. yours per implications ? or a scientific paper ?
your talk of guess-work as a means to scientific replication makes clear your approach.
yours
per

]]> By: EliRabett http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1249 EliRabett Sun, 03 Jul 2005 03:41:32 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1249 Per, in the MBH09 paper the only mention that any of the sets of tree ring data were represented by PCs was in the caption to a figure. It was also stated in the supplementary material that PCs were used to represent sets of data, and the maximum number of PCs used for each set with the clear implication that fewer were significant the further back one went. I would maintain that yes, in context it was more than reasonable to assume that Preisendorfers criteria was used in all cases including the tree rings. You might want to talk with the editors of Nature on their space limitations. I also am less than impressed with McIntyre's mathematical skills. Have you tried this? Per, in the MBH09 paper the only mention that any of the sets of tree ring data were represented by PCs was in the caption to a figure. It was also stated in the supplementary material that PCs were used to represent sets of data, and the maximum number of PCs used for each set with the clear implication that fewer were significant the further back one went. I would maintain that yes, in context it was more than reasonable to assume that Preisendorfers criteria was used in all cases including the tree rings. You might want to talk with the editors of Nature on their space limitations. I also am less than impressed with McIntyre’s mathematical skills. Have you tried this?

]]> By: per http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1248 per Sat, 02 Jul 2005 23:24:53 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1248 Dear Eli I believe MBH describe the use of Preisendorfer's for temperature PCs, but not for tree rings. According to you, it is sufficient to guess when MBH may (or may not) have used Preisendorfer's, when they do not say what they did ? Strangely enough, when steve McIntyre looked at the various data sets of MBH'98 using Preisendorfer's as a test, loads of the results MBH did use did not pass Preisendorfer's. So it seems that guessing is not enough. It needs to be spelled out. yours per Dear Eli
I believe MBH describe the use of Preisendorfer’s for temperature PCs, but not for tree rings.

According to you, it is sufficient to guess when MBH may (or may not) have used Preisendorfer’s, when they do not say what they did ? Strangely enough, when steve McIntyre looked at the various data sets of MBH’98 using Preisendorfer’s as a test, loads of the results MBH did use did not pass Preisendorfer’s.

So it seems that guessing is not enough. It needs to be spelled out.
yours
per

]]> By: Eli Rabett http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1247 Eli Rabett Sat, 02 Jul 2005 05:00:20 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1247 Per, your statement was "For example, in december last year on his blog, out of nowhere, Mann announces he used a statistical test called "Preisendorfer's". When, where and how we still don't know." which did not say, ""In dealing with the tree ring networks....." My reply was reasonable, MBH98 DID mention Preisendorfer's test as you point out in describing the calibration. On the other hand, while the paper did not specifically deal with the details of PCA for the tree ring networks, pray tell, why would anyone use different criteria for one analysis and not the other? Per, your statement was

“For example, in december last year on his blog, out of nowhere, Mann announces he used a statistical test called “Preisendorfer’s”. When, where and how we still don’t know.”

which did not say, “”In dealing with the tree ring networks…..”

My reply was reasonable, MBH98 DID mention Preisendorfer’s test as you point out in describing the calibration. On the other hand, while the paper did not specifically deal with the details of PCA for the tree ring networks, pray tell, why would anyone use different criteria for one analysis and not the other?

]]> By: Southpaw http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1254 Southpaw Fri, 01 Jul 2005 07:33:26 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1254 <strong>Barton's Attack on Science</strong> Over at Rhetoric & Rhythm, Mike Thomas remarked on Joe Barton's harrassing letter and had the following reader comment: Barton has every right - indeed, the obligation to his taxpaying constituents - to ask these sorts of questions So, where... Barton’s Attack on Science

Over at Rhetoric & Rhythm, Mike Thomas remarked on Joe Barton’s harrassing letter and had the following reader comment: Barton has every right – indeed, the obligation to his taxpaying constituents – to ask these sorts of questions So, where…

]]> By: per http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1246 per Thu, 30 Jun 2005 11:54:32 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1246 Dear Eli perhaps you would be so good as to acknowledge that the text you quoted refers to the calculation of temperature PCs, and not tree ring networks- the issue at hand. An application of Preisendorfer's to the tree ring data sets doesn't appear consistent with MBH'98; see http://www.climate2003.com/blog/preisendorfer.MBH98.htm yours per Dear Eli
perhaps you would be so good as to acknowledge that the text you quoted refers to the calculation of temperature PCs, and not tree ring networks- the issue at hand.

An application of Preisendorfer’s to the tree ring data sets doesn’t appear consistent with MBH’98; see http://www.climate2003.com/blog/preisendorfer.MBH98.htm
yours
per

]]> By: George M Hebbard http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1245 George M Hebbard Thu, 30 Jun 2005 11:24:44 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1245 The issue is the alleged unique sensitivity of the Bristle Cone pine series to recent CO2 increases. The question is not, has there be a recent return to temperatures previous to the LIA, but rather does this data show a potential increase to a unprecedented global temperature which might cause unknown climate effects. Remember, billions and eventually trillions of dollars are being directed at what many believe to be a disastrous witch hunt. Congress in only doing what NSF has not had the spine to attempt The issue is the alleged unique sensitivity of the Bristle Cone pine series to recent CO2 increases. The question is not, has there be a recent return to temperatures previous to the LIA, but rather does this data show a potential increase to a unprecedented global temperature which might cause unknown climate effects.

Remember, billions and eventually trillions of dollars are being directed at what many believe to be a disastrous witch hunt.

Congress in only doing what NSF has not had the spine to attempt

]]> By: Eli Rabett http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1244 Eli Rabett Thu, 30 Jun 2005 05:21:14 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1244 So Ed, what parts are missing? and per, MBH used Preisendorfer's selection rule in their 1998 paper, so it did not appear out of nowhere. http://www.umass.edu/newsoffice/archive/1998/042298climate.pdf "An objective criterion was used to determine the particular set of eigenvectors which should be used in the calibration as follows. Preisendorfer's (25) selection rule "rule N" was applied to the multiproxy network to determine the approximate number Neofs of signicant independent climatic patterns that are resolved by the network, taking into account the spatial correlation within the multiproxy dataset." Want to take another shot? So Ed, what parts are missing?

and per, MBH used Preisendorfer’s selection rule in their 1998 paper, so it did not appear out of nowhere.
http://www.umass.edu/newsoffice/archive/1998/042298climate.pdf

“An objective criterion was used to
determine the particular set of eigenvectors which should be used in the calibration as
follows. Preisendorfer’s (25) selection rule “rule N” was applied to the multiproxy network
to determine the approximate number Neofs of signicant independent climatic patterns
that are resolved by the network, taking into account the spatial correlation within the
multiproxy dataset.”

Want to take another shot?

]]> By: Ed Snack http://cstpr.colorado.edu/prometheus/?p=3511&cpage=1#comment-1243 Ed Snack Thu, 30 Jun 2005 02:38:33 +0000 http://sciencepolicy.colorado.edu/prometheusreborn/?p=3511#comment-1243 Lil' Dano pops his head up to make unfounded and false accusations, as usual. Mitch, that is not all the source code at all, it only deals with PC calculations. Check them out and it is obvious. Lil’ Dano pops his head up to make unfounded and false accusations, as usual. Mitch, that is not all the source code at all, it only deals with PC calculations. Check them out and it is obvious.

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