date: Fri Jul 15 11:06:31 2005
from: Phil Jones <p.jones@uea.ac.uk>
subject: Re: paleoT
to: Tom Wigley <wigley@cgd.ucar.edu>

    Tom,
        This Briffa series is just a three site average (trees from Tornetrask, Polar Urals
   and
    Taimyr) - all in northern Eurasia. It is therefore for a limited region and is likely
    just the summer, whereas some of the others have regressed on annual T for
    the NH (or north of 20N).
       Of these 3, the first two are in most of the other series (Esper, Crowley, Jones, Mann)
    and also for HF in Moberg. Not sure whether Taimyr is in any of the others.
    Esper uses a different standardization approach, but should have most of the
    same trees, but only TRW. The others use our reconstructions which have MXD
    is as well.
       Have you tried these correlations after extracting the LF trends (say residuals
    from a 30 or 50 yr filter)? Would expect some of them to be much, much lower.
      Keith's reconstruction that would be much better is the one that goes back to
    only about 1400. Do you have this?  Go here [1]http://www.ncdc.noaa.gov/paleo/paleo.html
    then click on paleo data, then on obtaining and look for Keith's - it says 600 years in
    the title. You can get the data.
    Cheers
    Phil
   At 21:57 14/07/2005, you wrote:

     Phil,
     I eventually refiltered all the paleo data and have compared these
     with likewise filtered MAGICC output. Very interesting results.
     Can you comment, off the record, on Keith's paleo series.
     Here are correlations of individual series against the 7 series average.
     (Different series lengths, but essentially same results over common lengths.)
     SERIES     1000-1610       1610-1995      1000-1995
     Briffa                  -.272                 .262                .207
     Esper                   .583                 .917                .687
     Crowley               .879                 .946                .902
     Jones                   .773                 .917                .861
     Mann                   .760                 .856                .822
     M&J-NH             .929                 .965                .936
     Moberg                .904                 .856                .871
     Correlations with the climate model are not the same -- but Briffa is
     again the clear outlier.
     Why?
     Tom.

   Prof. Phil Jones
   Climatic Research Unit        Telephone +44 (0) 1603 592090
   School of Environmental Sciences    Fax +44 (0) 1603 507784
   University of East Anglia
   Norwich                          Email    p.jones@uea.ac.uk
   NR4 7TJ
   UK
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