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Line 35: − 5) I am not sure whether it is wise to add me to the CA list, just because the reviewer is supposed to be impartial and a CA loses that appearance of impartiality if he has now been included as a CA - may want to check with Susan S. on this one to be sure - still happy to provide advice [Crowley] − − My own position on this is that you are an "unofficial" referee, who has (and still is) making a significant contribution - I see no conflict [Briffa] − --- − What we worry very much about, however, is that we should not produce a Figure that then conflicts with the picture of proxy evidence for Hemispheric mean warmth as a whole,shown in the main Chapter Figure. By showing a composite (as Tom has done) and scaling against another (30-90degrees N) temperature record - this is just what is done. [briffa] − − ABSOLUTELY RIGHT - CAN'T HAVE CONFLICT. [overpeck]... − − WHAT ABOUT THE IDEA THAT WE ONLY SHOW THE SERIES FOR THE MWP, SINCE THE COMPARISON TO THE 20TH CENTURY IS DONE WELL (AND BEST?) IN THE TEXT FIGS (WHICH I'M ATTACHING JUST IN CASE TOM DOESN'T HAVE, ALONG WITH THE TEXT - IF YOU HAVE TIME, TOM, PLEASE READ COMMENT ON ANYTHING YOU WISH, BUT CERTAINLY THE LAST 2000 YEARS BIT - ASSUME YOU'LL BE DOING THIS AT THE REVIEW STAGE ANYHOW...) ANOTHER THING THAT IS A REAL ISSUE IS SHOWING SOME OF THE TREE-RING DATA FOR THE PERIOD AFTER 1950. BASED ON THE LITERATURE, WE KNOW THESE ARE BIASED - RIGHT? SO SHOULD WE SAY THAT'S THE REASON THEY ARE NOT SHOWN? OF COURSE, IF WE ONLY PLOT THE FIG FROM CA 800 TO 1400 AD, IT WOULD DO WHAT WE WANT, FOCUS ON THE MWP ONLY [overpeck][http://tomnelson.blogspot.com/2011/12/overpeck-thing-that-is-real-issue-is.html]}} +
→Dendrochronology
As you probably know, I was originally invited to give a talk on The Topic (a scientific version of the The Troubles in Northern Ireland) that Rosanne gave before the NRC panel....I recommended that Keith give a talk to the NRC panel in my place because, in my estimation, he is the only other person in the world who can discuss in a totally objective way the hockystick and other reconstructions of past temperatures at the methodological level that is really at the heart of all the controversy, e.g. the hockeystick. [Ed Cook]
As you probably know, I was originally invited to give a talk on The Topic (a scientific version of the The Troubles in Northern Ireland) that Rosanne gave before the NRC panel....I recommended that Keith give a talk to the NRC panel in my place because, in my estimation, he is the only other person in the world who can discuss in a totally objective way the hockystick and other reconstructions of past temperatures at the methodological level that is really at the heart of all the controversy, e.g. the hockeystick. [Ed Cook]
...Peck--I almost sent this to Susan tonight, copied to you, but then thought I had better run it by you first, quickly. I think that Susan has to be notified--I fear that the tree-ring reconstructions really are in bad shape, and that the IPCC and chapter 6 have a big problem coming up. I'll be in the office tomorrow if you want to call--814???--but I want to notify Susan soon.--Richard[http://tomnelson.blogspot.com/2011/12/uh-oh-has-real-problem-fear-that-tree.html]}}
...Peck--I almost sent this to Susan tonight, copied to you, but then thought I had better run it by you first, quickly. I think that Susan has to be notified--I fear that the tree-ring reconstructions really are in bad shape, and that the IPCC and chapter 6 have a big problem coming up. I'll be in the office tomorrow if you want to call--814???--but I want to notify Susan soon.--Richard[http://tomnelson.blogspot.com/2011/12/uh-oh-has-real-problem-fear-that-tree.html]}}
{{cquote|5) I am not sure whether it is wise to add me to the CA list, just because the reviewer is supposed to be impartial and a CA loses that appearance of impartiality if he has now been included as a CA - may want to check with Susan S. on this one to be sure - still happy to provide advice [Crowley]
My own position on this is that you are an "unofficial" referee, who has (and still is) making a significant contribution - I see no conflict [Briffa]
---
What we worry very much about, however, is that we should not produce a Figure that then conflicts with the picture of proxy evidence for Hemispheric mean warmth as a whole,shown in the main Chapter Figure. By showing a composite (as Tom has done) and scaling against another (30-90degrees N) temperature record - this is just what is done. [briffa]
ABSOLUTELY RIGHT - CAN'T HAVE CONFLICT. [overpeck]...
WHAT ABOUT THE IDEA THAT WE ONLY SHOW THE SERIES FOR THE MWP, SINCE THE COMPARISON TO THE 20TH CENTURY IS DONE WELL (AND BEST?) IN THE TEXT FIGS (WHICH I'M ATTACHING JUST IN CASE TOM DOESN'T HAVE, ALONG WITH THE TEXT - IF YOU HAVE TIME, TOM, PLEASE READ COMMENT ON ANYTHING YOU WISH, BUT CERTAINLY THE LAST 2000 YEARS BIT - ASSUME YOU'LL BE DOING THIS AT THE REVIEW STAGE ANYHOW...) ANOTHER THING THAT IS A REAL ISSUE IS SHOWING SOME OF THE TREE-RING DATA FOR THE PERIOD AFTER 1950. BASED ON THE LITERATURE, WE KNOW THESE ARE BIASED - RIGHT? SO SHOULD WE SAY THAT'S THE REASON THEY ARE NOT SHOWN? OF COURSE, IF WE ONLY PLOT THE FIG FROM CA 800 TO 1400 AD, IT WOULD DO WHAT WE WANT, FOCUS ON THE MWP ONLY [overpeck][http://tomnelson.blogspot.com/2011/12/overpeck-thing-that-is-real-issue-is.html]}}
{{cquote|We actually eliminate records with negative correlations (this is mentioned breifly in the GRL article,), and we investigated a variety of weighting schemes to assure the basic robustness of the composite--but I certainly endorse your broader point here. Many of these records have some significant uncertainties or possible sources of bias, and this isn't the place to get into that. [Michael Mann]
{{cquote|We actually eliminate records with negative correlations (this is mentioned breifly in the GRL article,), and we investigated a variety of weighting schemes to assure the basic robustness of the composite--but I certainly endorse your broader point here. Many of these records have some significant uncertainties or possible sources of bias, and this isn't the place to get into that. [Michael Mann]
...
...
Sincerely, Jeff [Severinghaus][http://tomnelson.blogspot.com/2012/01/why-did-trees-allegedly-stop.html]}}
Sincerely, Jeff [Severinghaus][http://tomnelson.blogspot.com/2012/01/why-did-trees-allegedly-stop.html]}}
{{cquote|If you examine my Fig 1 closely you will see that the Campito record and Keith's reconstruction from wood density are extraordinarily similar until 1850. After that they differ not only in the lack of long-term trend in Keith's record, but in every other respect - the decadal-scale correlation breaks down. I tried to imply in my e-mail, but will now say it directly, that although a direct carbon dioxide effect is still the best candidate to explain this effect, it is far from proven. In any case, the relevant point is that there is no meaningful correlation with local temperature. Not all high-elevation tree-ring records from the West that might reflect temperature show this upward trend. It is only clear in the driest parts (western) of the region (the Great Basin), above about 3150 meters elevation, in trees old enough (>~800 years) to have lost most of their bark - 'stripbark' trees. As luck would have it, these are precisely the trees that give the chance to build temperature records for most of the Holocene. I am confident that, before AD1850, they do contain a record of decadal-scale growth season temperature variability. I am equally confident that, after that date, they are recording something else. [Malcolm Hughes][http://tomnelson.blogspot.com/2011/12/in-case-you-missed-it-hockey-stick-co.html]}}
{{cquote|If you examine my Fig 1 closely you will see that the Campito record and Keith's reconstruction from wood density are extraordinarily similar until 1850. After that they differ not only in the lack of long-term trend in Keith's record, but in every other respect - the decadal-scale correlation breaks down. I tried to imply in my e-mail, but will now say it directly, that although a direct carbon dioxide effect is still the best candidate to explain this effect, it is far from proven. In any case, the relevant point is that there is no meaningful correlation with local temperature. Not all high-elevation tree-ring records from the West that might reflect temperature show this upward trend. It is only clear in the driest parts (western) of the region (the Great Basin), above about 3150 meters elevation, in trees old enough (>~800 years) to have lost most of their bark - 'stripbark' trees. As luck would have it, these are precisely the trees that give the chance to build temperature records for most of the Holocene. I am confident that, before AD1850, they do contain a record of decadal-scale growth season temperature variability. I am equally confident that, after that date, they are recording something else. [Malcolm Hughes][http://tomnelson.blogspot.com/2011/12/in-case-you-missed-it-hockey-stick-co.html]}}
{{cquote|date: Mon Nov 13 09:29:49 2006 from: Keith Briffa subject: Re: Mitrie to: "Nanne Weber"
{{cquote|date: Mon Nov 13 09:29:49 2006 from: Keith Briffa subject: Re: Mitrie to: "Nanne Weber"
Between you and I , I believe there may be problems with the analysis of the Bristlecone data. We can talk by phone about this Keith[http://tomnelson.blogspot.com/2011/12/more-settled-science-keith-briffa-2006.html]}}
Between you and I , I believe there may be problems with the analysis of the Bristlecone data. We can talk by phone about this Keith[http://tomnelson.blogspot.com/2011/12/more-settled-science-keith-briffa-2006.html]}}
==Ice Cores==
==Ice Cores==