cc: "Hulme Mike (E-mail)" <m.hulme@uea.ac.uk>, "Mearns, Linda  (E-mail)" <lindam@ucar.edu>, "Wratt, David  (E-mail)" <d.wratt@niwa.cri.nz>,  "Whetton, Peter" <peter.whetton@dar.csiro.au>, "Jones, Roger" <roger.jones@dar.csiro.au>, "Hennessy, Kevin" <kevin.hennessy@dar.csiro.au>
date: Tue, 3 Aug 1999 12:25:00 +1000 
from: "Pittock,Barrie" <barrie.pittock@dar.csiro.au>
subject: RE: Chapter 3.
to: 'Timothy Carter' <tim.carter@vyh.fi>

Dear Tim,

Sorry to not be pulling my weight on Chapter 3 - I will try to look at it
again after getting a prelim. draft of 12 out to local reviewers later this
week.

Meanwhile, the question of the change in Precip. maps in the "Interim
Characterizations..." document: The point is NOT whether the other authors
howl in protest at having their regions blanked out, but which
representation of the results is appropriate to giving the best advice on
what changes to expect. As the object is NOT to prove that change will
occur, but rather to provide the best estimate of it, plus uncertainty, I
think the obviously best solution is to show all results, with the scatter
plots to show relation to natural variability. But I have accepted Mike's
compromise for the stuff he is supplying to the WWF, which is to show
results at one s.d.  If Mike can that for WWF, then he must be set up to do
it for IPCC, or I would have thought so. If he/you do not do so, I would
have thought you were misleading authors into thinking the changes in the
blanked out regions are not of practical importance, and this is clearly
wrong - they matter a lot in terms of implicit changes in the frequency of
extremes, and e.g., in the frequency of successive droughts which might
threaten a given water-dependent enterprise.

The great danger of doing things the way we are, in our rush to prepare
these IPCC reports, is that we are not submitting this stuff to peer review
before using it. This makes it even more important that we bend over
backwards to get it right. I know it is a bother, but that is life. I am
genuinely sorry to be such a stickler about it, but there we are.

Best regards,

Barrie.

Dr A. Barrie Pittock
Post-Retirement Fellow*, Climate Impact Group
CSIRO Atmospheric Research, PMB 1, Aspendale 3195, Australia
Tel: +61 3 9239 4527, Fax: +61 3 9239 4688, email:
<barrie.pittock@dar.csiro.au>
WWW: http://www.dar.csiro.au/res/cm/impact.htm

* As from 1 March 1999 I have become a CSIRO Post-Retirement Fellow. This
means I do not have administrative responsibilities, and am  working
part-time, primarily on writing for the Intergovernmental Panel on Climate
Change. Please refer any administrative matters or contract negotiations for
the CIG to Dr. Peter Whetton, the new Group Leader, at
<peter.whetton@dar.csiro.au>, tel. +61 3 9239 4535.

"Far better an approximate answer to the right question which is often
vague, than an exact answer to the wrong question which can always be made
precise." J.W. Tukey as cited by R. Lewin, Science 221,636-639.

> -----Original Message-----
> From:	Timothy Carter [SMTP:tim.carter@vyh.fi]
> Sent:	Monday, 2 August 1999 22:58
> To:	Pittock,Barrie
> Subject:	Re: Chapter 3.
> 
> Barrie,
> 
> I have noted your flagged points for Ch 3, and I did see some of the
> correspondence with Mike about the WWF scenarios, etc. so I understand
> your
> concerns on that. 
> 
> I'm not sure about the feasibility of replacing all of the maps Mike has
> produced with "more tolerant" 1 SD limited maps. I see your point, but
> perhaps we only need to act on this if we get howls of protest from the
> authors whose regions are blanked out on the maps. I suppose it might have
> been better (though tricky to do in a user-friendly way) to show changes
> in
> ALL regions with a separate shading mask over 1 SD or 2 SD modelled
> natural
> variability. However, recall that the scatter plots, when they're ready,
> will show ALL information, albeit for regional domains chosen by us.
> 
> Please remind Peter about the papers to send - I am in the office Tuesday
> before leaving for London Wednesday morning.
> 
> In addition, I hope that Linda will be in touch with you about updating
> section 3.7. Since neither of you will be in attendance, we won't be
> dealing much with this section in London - I am relying on you two to help
> me out ready for the First-order draft!
> 
> I also appreciate that you have Ch 12 to work with too.
> 
> Best regards,
> 
> Tim
> 
> 
> ************************************************
> 
> Dr. Timothy Carter
> Finnish Environment Institute
> Box 140, Keskatu 6, FIN-00251 Helsinki, FINLAND
> 
> Tel: +358-9-40300-315
> Fax: +358-9-40300-390
> Email: tim.carter@vyh.fi
> 
> ************************************************
