Saturday, June 2, 2012

4823.txt

cc: m.hulmeatXYZxyz.ac.uk
date: Fri, 30 Apr 1999 08:53:32 +0100
from: Merylyn McKenzie Hedger <merylyn.hedgeratXYZxyzironmental-change.oxford.ac.uk>
subject: RE: Fwd. re: US views on possible UK cooling- FYI
to: "Jenkins, Geoff" <gjjenkinsatXYZxyzo.gov.uk>

Please tell Mike McCracken! It's not about evenhandeness though-it's
about capturing all possibilities. Mike Hulme's new work on uncertainty
does allow a way of this remote risk being accounted for despite it's
non appearance in the GCMs.

Where are my Buenos Aires photos? It will be Bonn soon.

M

> -----Original Message-----
> From: Jenkins, Geoff [SMTP:gjjenkins@meto.gov.uk]
> Sent: 29 April 1999 10:11
> To: 'Merylyn McKenzie Hedger'
> Cc: Mitchell, John FB; 'penny_bramwell@detr.gsi.gov.uk'
> Subject: RE: Fwd. re: US views on possible UK cooling- FYI
>
> Thanks for this info Merylyn - the ability to get HadCM2 widely used
> in the
> US Assessment came about through your meeting with Mike McCracken - so
> thanks for the tip off. My personal view is that it would be a waste
> of time
> putting a cooling scenario in UKCIP - where would it come from? no
> model
> shows any cooling so it would have to be totally invented. Sounds like
> the
> usual even handedness in the US for political reasons gone made.
>
> Cheers
>
> Geoff
>
> > -----Original Message-----
> > From: Merylyn McKenzie Hedger
> > [SMTP:merylyn.hedger@environmental-change.oxford.ac.uk]
> > Sent: 23 April 1999 13:06
> > To: 'penny_bramwell@detr.gsi.gov.uk';
> 'david_warrilow@detr.gsi.gov.uk';
> > 'gjjenkins@meto.gov.uk'; 'm.hulme@uea.ac.uk'
> > Cc: 'cathy_johnson@detr.gsi.gov.uk'
> > Subject: Fwd. re: US views on possible UK cooling- FYI
> >
> > Dear Colleague,
> >
> > This email arose from a discussion I first had with Granger Morgan
> who
> > has master-minded the US approach on socio-economic scenarios. When
> > shown the material on the UKCIP98 sceanrios his first reaction was
> what
> > about cooling, and Mike McCracken jumped in too. The US National
> > Assessment Synthesis team has gone for extremes on their economic
> and
> > demographic projections to capture all eventualities so I suppose
> > that's a different philosophy, reflected here.
> >
> > By the way, most of the US National Assessment studies have used
> HADCM2,
> > (when I went to Washington last year they were only going with the
> > Canadian model, so Geoff did good work there). In some places, this
> has
> > produced results in sharp contrast to the Canadian model causing
> > problems. The NCAR model is just ready for use.
> >
> > I hope to do the overall report on the meeting next week. I am
> telling
> > Mike McCracken I have forwarded his thoughts! My response when we
> spoke
> > was that currently UKCIP was focusing on getting awareness and
> action on
> > the changes which were likely in the 'near' term.
> >
> > Merylyn
> > -------------------------------------------
> > From Mike McCracken
> >
> > -------
> >
> > Dear Merylyn--To follow-up on our discussion with Granger in
> Atlanta, I
> > went and looked at the plots I have. Both Granger and I would
> interpret
> > this as iimplying that there is indeed a chance of a cooling
> scenario
> > for
> > the UK, even if not a full crash of the Atlantic circulation.
> >
> > Thanks again for coming to Atlanta, Mike
> >
> > >Date: Wed, 21 Apr 1999 13:43:20 -0400
> > >To: gmorgan
> > >From: Mike MacCracken <mmaccracatXYZxyzth.usgcrp.gov>
> > >Subject: North Atlantic overturning
> > >Cc:
> > >Bcc:
> > >X-Attachments:
> > >
> > >Dear Granger--Following up on our discussion in Atlanta with
> Merylyn
> > >McKenzie Hedger and the risk of cooling in the UK and Europe, I
> went
> > back
> > >and checked the figures for predictions for the North Atlantic
> > circulation
> > >changes from the GCDL and Hadley models:
> > >
> > >1. GFDL:
> > >
> > >Control--20 Sverdrups
> > >up to 2 times CO2 at 1% per year and stabilize--drops to about 7
> and
> > then
> > >recovers over long time
> > >up to 4 times CO2 at 1% per year and stabilize--drops to about 2
> and
> > stays
> > >there
> > >
> > >2. Hadley Centre model
> > >
> > >control--about 22-23 Sverdrups
> > >IPCC BAU-drops to about 17
> > >up to 4 times CO2 at 2% per year--drops to about 14 and slwoly goes
> up
> > to
> > >about 16
> > >
> > >The dates on the Hadley figure are a bit strange--their BAU case
> starts
> > >dropping in about 1980-90. Their up to 4 times CO2 drops in about
> 1890
> > >(yes, 110 years ago), so I assume they started their run in about
> 1860
> > and
> > >started the sharp CO2 increase then.
> > >
> > >
> > >Thus, with respect to Merylyn's comments about the UK model not
> showing
> > a
> > >collapse, true, but. Basically, the GFDL run does show a stronger
> > >reduction, but the Hadley model does also show a significant
> decrease
> > as
> > >well. I think I might worry about a potential cooling.
> > >
> > >Mike
> > >
> > >
> > >
> >
> > Michael C. MacCracken, Ph.D.
> > National Assessment Coordination Office
> > Suite 750
> > 400 Virginia Avenue
> > Washington DC 20024
> >
> > Tel: (202) 314-2230 (Main number for NACO and for Robert Cherry,
> Admin.
> > Asst.)
> > Tel: (202) 314-2233 (office and voicemail)
> > Fax: (202) 488-8681 or (202) 488-8678
> > E-mail: mmaccrackenatXYZxyzcrp.gov
> > USGCRP Home Page: http://www.nacc.usgcrp.gov/
> >
> >
> >
> >

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