date: Fri Apr  5 15:52:00 2002
from: Keith Briffa <k.briffa@uea.ac.uk>
subject: Fwd: Re: Briffa & Osborn piece
to: t.osborn@uea.ac.uk

     To: "Michael E. Mann" <mann@multiproxy.evsc.virginia.edu>,  p.jones@uea.ac.uk,
     tcrowley@duke.edu, rbradley@geo.umass.edu, mhughes@ltrr.arizona.edu,
     drdendro@ldeo.columbia.edu, rkerr@aaas.org, bhanson@aaas.org
     From: Keith Briffa <k.briffa@uea.ac.uk>
     Subject: Re: Briffa & Osborn piece

     Dear Mike, (and interested colleagues)
     Given the list of people to whom you have chosen to circulate your message(s),
     we thought we should make a short, somewhat formal response here.  I am happy
     to reserve my informal response until we are face to face.
     We did not respond earlier because we had more pressing issues , to do with funding

      applications, to deal with. This is not the place to go into a long or over-detailed
     response

     to all of your comments but a few brief remarks might help to clear up a couple of
     misconceptions.

     You consider our commentary on Ed and Jan's paper
     "more flawed than even the paper itself"
     on the basis that scaling the relationship between full Northern Hemisphere and
     extratropical Northern Hemisphere is *much* more problematic than even any of
     the seasonal issues we discuss.  In fact we did not do this.  Rather, we scaled
     the average only of the land areas, north of 20 degrees N extracted from your
     reconstructions, just as you stress, in your comments on the Esper et al.
     paper, was what should have been done.  In fact you say "if the authors had
     instead used the actual (unsmoothed) instrumental record for the
     extratropical northern hemisphere to scale their record, their reconstruction
     would be much closer to MBH99".
     Mike, as it turns out, this is precisely what Tim and I did and what we show in
     the Figure in the *Science* piece!

     You also considered that once the scaling of your own data and the Esper et
     al. curve was correctly done, the two would be much closer together, but of
     course when you ask if the difference is statistically significant (taking into
     account the revised variances of the series), there is perhaps little effect!

     The fact that we have rescaled only the
     extra tropical land to represent your data is not clear from the text, so we
     can see why you may not have appreciated this, but I think you will concede
     that this fact negates much of what you say and we acted "more correctly"

      than you realised.  Blame *Science* for being so mean with their
     space allocation - but do not blame us for misrepresenting your data.  In this
     (unrefereed) piece, we were only concentrating on one issue; that of the
     importance of the method of scaling and its effect on apparent "absolute"
     reconstruction levels.  In our draft, we went on to say that this was crucial
     for issues of simple model sensitivity studies and climate detection, citing
     the work of Tom Crowley and Myles Allen, but this fell foul of the editor's
     knife.
     Again, the point you made to Ed on scaling against the trend is wholly
     consistent with our discussion in the perspective piece.  I certainly do not
     consider that scaling any single limited-coverage (possibly seasonally biased)
     averaged record is an appropriate way of reconstructing Hemispheric
     temperature.  This is just what several of the records do, though, certainly
     the original Bradley and Jones series, the  Jones et al.series , and that of Crowley.

      However, even your own series, prior to 1400, could be taken to
     represent a major western N. American bias as regards evidence of Hemispheric
     changes.
     Finally, I have to say that I, for one, do not feel constrained in what I say
     to the media or write in the scientific or popular press, by what the sceptics
     will say or do with our results.  We can only strive to do our best and address
     the issues honestly.  Some "sceptics" have their own dishonest agenda - I have
     no doubt of that.  If you believe that I, or Tim, have any other objective but
     to be open and honest about the uncertainties in the climate change debate,
     then I am disappointed in you also.
     At 12:39 PM 3/22/02 -0500, Michael E. Mann wrote:

     Keith and Tim,
     Sadly, your piece on the Esper et al paper is more flawed than even the paper itself.
     Ed, the AP release that appeared in the papers was even worse. Apparently you allowed
     yourself to be quoted saying things that are inconsistent with what you told me you had
     said.
     You three all should have known better. Keith and Tim: Arguing you can scale the
     relationship between full Northern Hemisphere and extratropical Northern Hemisphere is
     *much* more problematic than even any of the seasonal issues you discuss, and this isn't
     even touched on in your piece. The evidence of course continues to mount (e.g., Hendy et
     al, Science, a couple weeks ago) that the tropical SST in the past centuries varied far
     more less in past centuries. Hendy et al specifically point out that there is little
     evidence of an LIA in the tropics in the data. The internal inconsistency here  is
     remarkably ironic. The tropics play a very important part in our reconstruction, with
     half of the surface temperature estimate coming from latitudes below 30N. You know this,
     and in my opinion you have knowingly misrepresented our work in your piece.
     This will be all be straightened out in due course. In the meantime, there is a lot of
     damage control that needs to be done and, in my opinion, you've done a disservice to the
     honest discussions we had all had in the past, because you've misrepresented the
     evidence. Many of us are very concerned with how Science dropped the ball as far as the
     review process on this paper was concerned.  This never should have been published in
     Science, for the reason's I outlined before (and have attached for those of you who
     haven't seen them). I have to wonder why the functioning of the review process broke
     down so overtly here,
     Mike
     _______________________________________________________________________
                          Professor Michael E. Mann
               Department of Environmental Sciences, Clark Hall
                           University of Virginia
                          Charlottesville, VA 22903
     _______________________________________________________________________
     e-mail: mann@virginia.edu   Phone: (434) 924-7770   FAX: (434) 982-2137
            [1]http://www.evsc.virginia.edu/faculty/people/mann.shtml

     --
     Professor Keith Briffa,
     Climatic Research Unit
     University of East Anglia
     Norwich, NR4 7TJ, U.K.

     Phone: +44-1603-593909
     Fax: +44-1603-507784
     [2]http://www.cru.uea.ac.uk/cru/people/briffa/

   --
   Professor Keith Briffa,
   Climatic Research Unit
   University of East Anglia
   Norwich, NR4 7TJ, U.K.

   Phone: +44-1603-593909
   Fax: +44-1603-507784
   [3]http://www.cru.uea.ac.uk/cru/people/briffa[4]/

