date: Fri Aug 12 17:08:42 2005
from: Phil Jones
subject: Re: [Fwd: Storch drift]
to: mann@psu.edu
OK. Keith is also away next week. He's
already gone.
He'll need to look more at all this before the
next IPCC meeting in December.
You should have seen some of the crap
comments he got. Not yours, but some
of the other authors on the paleo chapter.
People who you think ought to know
better. Most relating to MM. All mostly
ignored. You'll be able to register to get
the draft by early Sept.
Cheers
Phil
At 16:49 12/08/2005, you wrote:
Thanks Phil,
Can you tell Keith (confidentially) that Ammann and Wahl are submitting a comment to
Science pointing out that von Storch knowingly did not apply the MBH98 procedure, and
that all of the conclusions in that paper are wrong! There may be calls on Science to
retract VS04, because the mistake undermines every single conclusion!!
mike
Phil Jones wrote:
Mike,
We have the Italian paper Well Keith does for his AR4 work.
Submission day for AR4 is today by the way.
I think the Italian journal is the one from a conf I went to
3 weeks after the Berne meeting. I didn't bother sending
anything to the Italian meeting either, just like Berne. The
journal the Italians were planning did look obscure when
I was there, but I didn't write anything down, as I had
no intention of sending anything.
Yes the MSU stuff is out. There will be something
in Nature next week on it.
Off next week as a break from IPCC.
Cheers
Phil
At 16:21 12/08/2005, you wrote:
Hi Caspar,
Thanks for the comments. Frankly, Von storch is being duplicitous here. He may tell
certain audiences (like the NCAR group last month) that he is not suggesting that the
GKSS simulation is reealistic, because he knows he'll get skewered if he claims
othewise. But then he turns around to the press, and talks about how the Moberg et al
reconstruction matches their model, etc. I frankly consider this dishonest, at best!
If what Stefan says is true (that the entire long-term trend, including the cold LIA in
the model, is all due to the spinup problem), then it completely invalidates the use of
that model for testing statistical reconstruction methodologies which require
physically-consistent patterns of variance in the calibration period to reconstruct the
past. But that's a separate issue.
As we now know, the far more damning fact is that Von Storch et al knowingly applied a
procedure which is not the MBH98 procedure, and they think they can get away w/
admitting this now in some obscure Italian journal which isn't even in the ISI
database.
Tim/Phil/Keith: you may not know about the latter, but Caspar should be able to fill you
in on this shortly...
Meanwhile, lets enjoy the media fiesta on MSU...
Mike
Caspar Ammann wrote:
Stefan,
this is very important news indeed. The runs will get a huge hit from this. The only way
a coupled model can get a continued trend (without invoking an energy leak somewhere) is
when there is a terrible deep-ocean spin up available even for their present day
initialization, not to speak about the subsequent shock to pre-industrial conditions.
Did you really say 1.5 degrees? Wow, that is quite a bit. Seems to me they must have
used Levitus ocean data with an atmospheric restart file, then hit it with the solar/GHG
changes. It seems rather large of a drop to come from a fully coupled stage. 1.5 degrees
is about 30% too large to be exclusively from the atmospheric composition and solar
irradiance, thus my suspicion regarding levitus. Now it would be important to know what
happend because some people are using the run as a possible real-world scenario
(although Hans in talks does not claim so).
Caspar
PS Now, bare in mind that the Science paper applies to the reconstruction, and for the
general discussion the influence of spinup should not make that big of a difference
(other than inflating the difference of the coldest period to the calibration period,
which creates some issues discussed by Mike previously).
Michael E. Mann wrote:
------------------------------------------------------------------------
Subject:
Storch drift
From:
Stefan Rahmstorf
Date:
Thu, 11 Aug 2005 15:37:27 +0200
To:
mann@psu.edu
To:
mann@psu.edu
CC:
Gavin Schmidt , Keith Briffa ,
t.osborn@uea.ac.uk
Hi Mike,
here is some interesting new info on the drift problem in the VS04 runs. Irina Fast and
Gerd Bürger submitted a comment about this to Science some months ago; it was rejected
and they did not pursue it. I'm trying to encourage them to resubmit this elsewhere. I
do not have the ms. but have seen several graphs. There are two key points.
1. The ECHO-G run started at year 900, the VS04 paper of course shows only results
starting from year 1000. I've seen the full run now. Between 900 and 1000, the NH
temperature drops by about 1.5 ºC! That's how severe their initialisation problem is.
From my experience of how the THC responds after such step-function changes in forcing,
the strong warming from 1050-1150 in VS04 could well be a rebound effect from the 1.5 ºC
cooling that precedes it, since the THC tends to oscillate on such a time scale when
forced rapidly.
2. Irina has run ECHO-G initialised with modern climate and then switching to
pre-industrial conditions similar to the run shown by VS04, but without any further
variability in the forcing. Thus, this shows the pure drift from initialising this run -
this is what Tim has been estimating in MAGICC. The actual drift in ECHO-G is even
larger and more persistent than what Tim found: there is a cooling between the years
1000 and 2000 of over 0.6 ºC, and this is an almost linear trend over the whole time.
I.e., not just drifting during the first few centuries, but over the entire 1000-year
period.
Cheers, Stefan
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology Phone: (814) 863-4075
503 Walker Building FAX: (814) 865-3663
The Pennsylvania State University email: mann@psu.edu
University Park, PA 16802-5013
[1]http://www.evsc.virginia.edu/faculty/people/mann.shtml
Prof. Phil Jones
Climatic Research Unit Telephone +44 (0) 1603 592090
School of Environmental Sciences Fax +44 (0) 1603 507784
University of East Anglia
Norwich Email p.jones@uea.ac.uk
NR4 7TJ
UK
----------------------------------------------------------------------------
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology Phone: (814) 863-4075
503 Walker Building FAX: (814) 865-3663
The Pennsylvania State University email: mann@psu.edu
University Park, PA 16802-5013
[2]http://www.evsc.virginia.edu/faculty/people/mann.shtml
Prof. Phil Jones
Climatic Research Unit Telephone +44 (0) 1603 592090
School of Environmental Sciences Fax +44 (0) 1603 507784
University of East Anglia
Norwich Email p.jones@uea.ac.uk
NR4 7TJ
UK
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