Wednesday, May 2, 2012


date: Wed, 19 Nov 2008 08:11:37 +0000
from: Rob Wilson <>
subject: Re: a request
to: Keith Briffa <>, Tom Melvin <>

Hi Keith and Tom,
first, please note that I am based at St. Andrews now - so e-mail and address (in
signature) are different.
Thanks for considering me as a "fair" referee. I am also busy putting together a proposal
with Neil Loader for Dec 1st so I am aware how tense the next few weeks could be.
What you propose is indeed relevant, especially w.r.t. the MXD data and the regional
'divergence' noted in your 2002 paper. I would be happy to be a referee, but I think it
only fair if I make some brief critical comments at this early stage w.r.t. your project:
1. The 400 chronology database you plan to work with is somewhat outdated and many of the
chronologies do not go into the 1990s. I think this could be a potential problem and any
reviewer might be quite sceptical to see yet more money put into a data-set which has been
processed multiple times.
Importantly, with greatest warming being in the last decade or so, a crucial test
for any divergence related project would be to assess whether the chronologies can model
that recent warming. This will likely not be possible with the current data set. It may be
crucial to add in to your proposal an update section as well. I understand that it is not
possible to update all 400 sites, but from the current data that are available, it is
possible to identify those sites with the strongest climate signal. Surely the project
could be greatly strengthened if some of these keys sites could be updated to present.
There is certainly much more data out there than the original 400 sites and you may need to
consider expanding your analysis beyond the original data-set.
2. I think it should be made clear that divergence is not noted everywhere and some areas
appear to be worse than others. E.g. Alaska and the NW Territories appear to be a
particular hot spot. However, in the Millennium project we have not noted any calibration
issues in the recent period.
There are also a whole ream of potential factors that could lead to a divergence
phenomenon. Yes, your wording is carefully worded (e.g. "overcoming at least part of the
apparent divergence "), but I think you must consider all possible factors in your
analysis. We certainly should be careful in taking the instrumental data as bible truth in
some locations. There is also my Tmax hypothesis (which I know you do not agree with) which
has now been tested in both the Pyrenees and N. Yukon and appears to hold in those regions
where there is a significant difference in turned between Tmin and Tmax (something that I
have been meaning to test in a more global way).
3. You need to carefully rationalise why you need 30 months for such a project. Even if you
processed one RW and one MXD chronology per day, there would be a lot of time left over and
I am sure the chronologies can be processed much quicker than that.
I hope these comments are of some use
Keith Briffa wrote:

Dear Rob
Please see attached letter
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784

Dr. Rob Wilson
Lecturer in Physical Geography
School of Geography & Geosciences
University of St Andrews
St Andrews. FIFE
KY16 9AL
Scotland. U.K.
Tel: +44 01334 463914
Fax: +44 01334 463949


".....I have wondered about trees.

They are sensitive to light, to moisture, to wind, to pressure.
Sensitivity implies sensation. Might a man feel into the soul of a tree
for these sensations? If a tree were capable of awareness, this faculty
might prove useful. "

"The Miracle Workers" by Jack Vance

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