date: Wed, 31 Mar 1999 10:44:00 +0300
from: Timothy Carter <tim.carteratXYZxyz.fi>
subject: Re: Scaled scenarios
Hope your trip to India went well.
I am still finalising Ch 3 (we have a one week extension).
Some strictly offline thoughts about the current situation re. scaled
You probably saw Linda's admonitions about the email I sent out to TAR
I am forwarding my reply (I hope you have her original) and her responses
at the end of this message. I am also copying Neil Leary's responses to
questions about the same topic.
Is this a storm in a teacup? I would like to regard it as such, but I think
opinions have become too deep seated to dismiss it now. I feel that perhaps
it was a tactical error to table the paper in Geneva and for me to follow
it up with the proposal to develop these scenarios. I can appreciate that
it can be seen as a self-serving exercise, given that we don't have the
TGCIA stamp of approval. Moreover, I have included a section in Ch 3 that
summarises the approach - maybe not so wise without fullscale support from
my writing team! Linda is dead against the concept of IPCC seemily
approving the provision of new scenarios that are "deeply flawed" and not
supported by the wider community, and Barrie is concerned (as we are) that
they are not "used" for anything other than guidance (i.e. guided
In hindsight it would probably have been better to say nothing, do the
work, get it published and table it as a set of ready guidance information
prepared independently of IPCC. It could then be adopted by whoever wishes
to use it (but, and that was the point, almost certainly too late to make
This is precisely what Filippo is doing - I don't hear any complaints about
his approach, though his analysis (which, while less controversial, is also
open to criticism) will presumably find itself a prominent position in
Chapter 10. Are the motives of authors supporting WG I chapters somehow
more altruistic/less self- serving than than those attempting to assist in
I suppose one compromise solution would be to summarise the Filippo-type
analysis of DDC outputs in Ch 3 (or use CMIP2 outputs - I have seen a
recent CMIP2 intercomparison by Jouni R�is�nen for N. Europe of 12
transient GHG 1% per year outputs at doubled CO2; Jouni is at the Rossby
Centre and will be at ECLAT), raise the SRES consistency issue, but do not
attempt to provide scaled scenarios. I suspect, even if we had called a
TGCIA meeting, we would have ended up in an argument over scaling that
would not have been resolved. Opinions, and interests, are too polarised.
It's difficult enough getting the basic stuff on paper for the respective
IPCC chapters without having a smouldering tinder box in the background. I
think we may have to retreat somewhat on this one; by all means do the
work, but independently of IPCC; let them approach us rather than vice
versa. I'd appreciate your opinion.
P.S. Thanks for sending your registration form.
Here is Neil Leary's response to my inquiry about the role of these scenarios:
(3) Regarding TSU support for an El Greco like report -- are hard copies
of color maps for distribution to WG2 authors really necessary? Couldn't
this be done electronically, with data and maps posted on the DDC? What's
the advantage of providing hard copies of color maps? Would all LAs really
benefit from having them? At an estimated cost of $1.75 per color map x X
maps x roughly 200 copies, this would not be a trivial expense. Perhaps we
could discuss at the CLA meeting when you present your results what would
make the most sense? Or from your perspective do we need to resolve before
then how we will distribute the scenarios?
(4) My sense of the Geneva meeting is that there was approval, at least
implicitly, for developing scaled climate scenarios for the SRES
projections. What is unclear is what would be done with the new,
unpublished scaled scenarios. I forwarded to Jim McCarthy and Osvaldo
Canziani the response Barrie Pittock sent to you. They are chewing on
Barrie's admonition to not use the new scenarios to scale impacts. We will
probably have a discussion and decision at the CLA meeting in May about how
far we should take scaling of impacts.
Here is Linda's response to my reply:
>Date: Tue, 30 Mar 1999 16:27:38 -0700 (MST)
>From: Linda Mearns <lindamatXYZxyz.ucar.edu>
>Subject: Re: Feb 27 e-mail - what the hell is going on?
>To: tim.carteratXYZxyz.fi (Timothy Carter)
>>Day late: I have been off with le flu.
>I have been away and then also out sick.
>>I was under the impression that the Geneva meeting participants gave broad
>>encouragement for a set of interim scenarios to be prepared based on
>>scaling methods, SRES emissions scenarios and DDC model patterns. This mail
>>was directed ONLY to CLAs of the regional chapters (of which Barrie is one
>>for Australasia) to clarify the usefulness of such an exercise and to ask
>>if the regions proposed for this analysis were satisfactory.
>However, Tim, it has never been made clear to these impacts people
>WHAT THE LIMITATIONS OF THESE SCENARIOS ARE.
>OF COURSE THEY ARE GOING TO BE ENTHUSIASTIC IN PRINCIPLE IF THE
>``NEWEST'' SCENARIOS ARE PRESENTED TO THEM.
>>These scenarios, if they are constructed (and your comments don't exactly
>>provide balm to salve my own reservations), will presumably only have to be
>>described in Chapter 3 if they are adopted for guidance by WG II TAR
>>authors. That is a decision for the CLAs (e.g. Barrie is sceptical - others
>>are more positive) and, ultimately, the leadership and Bureau. The
>>scenarios are not even constructed yet! That is why neither chapter 3 nor
>>chapter 13 needs entered my mind in sending that email out.
>BARRIE IS SCEPTICAL AND OTHERS LESS SO BECAUSE BARRIE UNDERSTANDS THE
>PROBLEMS WITH THE SCENARIOS AND THE OTHERS DON'T.
>>OK, perhaps I should have copied it to you, though I really considered this
>>an information gathering exercise for the people actually engaged in
>>constructing these interim scenarios. And scenarios they are, for guidance
>>(as stated in the email), nothing more. Mike and I will be working on them.
>>CLAs can "take them or leave them". As he rightly points out, Filippo is
>>engaged in analysing the DDC model outputs NOT in "scenario" development,
>>as such. However, we are trying to co-ordinate the regions covered and the
>>methods adopted. Filippo has actively consulted Lal, Richard Jones and
>>Peter Whetton on this - hence the email was copied to them (Lal is Asia
>>Please don't take this personally Linda - you are reading things into one
>>email message that really aren't there. Of course you are in "the loop" on
>>all matters relevant to Ch 3 and 13. But I didn't think you wanted to be
>>involved in the planning and construction of the scaled scenarios, and that
>>was the basis of that mail.
>I am not taking this personally, although I realize from the tone of my
>you may think that I am. I am speaking from a position of deep scientific
>Unfortuntely, from our interactions in Geneva, I was really left with the
>feeling that you, and I do mean you personally REALLY WANT THESE
>SCENARIOS TO BE USED REGARDLESS OF THEIR FLAWS. I THINK IT IS
>INAPPROPRIATE FOR ONE OR TWO PEOPLE TO BE DETERMINING WHETHER THESE
>ARE TO BE USED, FOR GUIDANCE OR ANYTHING ELSE,
>ESPECIALLY WHEN THOSE PARTICULAR INDIVIDUALS HAVE A DEEP INVESTMENT IN
>THE METHODS BEING USED TO PRODUCE THEM.
>THIS IS WHY I REACTED AS I DID.
>WHAT IS PERHAPS MOST DISTURBING ABOUT ALL THIS IS THAT THIS SHOULD BE A
>FOR THE TGCIA TO BE HANDLING, AND MARTIN REMAINS SILENT AND APPARENTLY
>I REGRET IF I AM BEING UNDULY SCEPTICAL OF YOUR MOTIVES AND SO FORTH, BUT
>I'M SURE YOU CAN UNDERSTAND MY CONCERNS GIVEN THE DISCUSSIONS THAT WENT ON
>I ALSO THINK IT IS NAIVE TO SUGGEST THAT CHAPTER 13 NEED NOT BE CONCERNED
>WHAT IS BEING DEVELOPED WITH THESE NEW SCENARIOS.
>I HOPE OVER TIME THAT WE CAN COME TO A POSITION OF MUTUAL TRUST AROUND ALL
>THIS NEW SCENARIO BUSINESS, BUT THAT WILL TAKE TIME AND EFFORT.
> Dr. Linda O. Mearns Phone: 303 497 8124
> Scientist Fax: 303 497 8125
> Environmental and Societal Impacts Group e-mail: lindamatXYZxyzr.edu
> NCAR P.O. Box 3000
> Boulder, CO 80307
Dr. Timothy Carter
Finnish Environment Institute
Box 140, Kes�katu 6, FIN-00251 Helsinki, FINLAND