Monday, December 12, 2011

1066149334.txt

From: "Michael E. Mann" <mann@virginia.edu>
To: Caspar Ammann <ammann@ucar.edu>
Subject: Re: Fwd: Re: draft
Date: Tue, 14 Oct 2003 12:35:34 -0400
Cc: Tim Osborn <t.osborn@uea.ac.uk>, Malcolm Hughes <mhughes@ltrr.arizona.edu>, Keith Briffa <k.briffa@uea.ac.uk>, rbradley@geo.umass.edu, tcrowley@duke.edu, omichael@princeton.edu, jto@u.arizona.edu, Scott Rutherford <srutherford@rwu.edu>, Tom Wigley <wigley@ucar.edu>, p.jones@uea.ac.uk, Kevin Trenberth <trenbert@cgd.ucar.edu>

thanks Caspar,
I agree--its important to emphasize this point, and I'm glad you recognized that we were
underplaying it...
mike
At 10:25 AM 10/14/2003 -0600, Caspar Ammann wrote:

Mike,
looks good to me. It is one of these points where they can persuade journalists that
they are 'correct' and it actually got into newspapers and finally to the senate floor
this way. The more we are able to explain why the first half of the 20th century warmed
up naturally, the more confidence we get on the detection of the anthropogenic signal
afterwards.
Caspar
Michael E. Mann wrote:

Dear All,
In response to Caspar's suggestion, which I agree with, I propose rephrasing item "2"
as follows:
2) The statement by S03 that the Mann and Jones [2003] reconstruction "clearly shows
temperatures in the MWP that are as high as those in the 20th century" is misleading if
not false. M03 emphasize that it is the late, and not the early or mid 20th century
warmth, that is outside the range of past variability. Mann and Jones emphasize
conclusions for the Northern Hemisphere, noting that those for the Southern Hemisphere
(and globe) are indeterminate due to a paucity of southern hemisphere data. Consistent
with M03, they conclude that, late 20th century Northern Hemisphere mean temperatures
are anomalous in a long-term (nearly two millennium) context.
Any comments?
Thanks,
mike

Delivered-To: [1]mem6u@virginia.edu
Date: Tue, 14 Oct 2003 09:18:37 -0600
From: Caspar Ammann [2]<ammann@ucar.edu>
Organization: NCAR
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624
Netscape/7.1 (ax)
X-Accept-Language: en-us, en
To: "Michael E. Mann" [3]<mann@virginia.edu>
Subject: Re: draft
Hi Mike,
it now looks good to me indeed including the new last paragraph following Tom's wording.
The only point I would highlight a little more is in point 2): Maybe it could be stated
that the early part of the 20th century is within the natural range whereas the late
20th century, the main point of the AGU position statement and also in M03, is clearly
outside. Please also add a second 'n' in my name...
Cheers, and thanks for your momentum on this,
Caspar
Michael E. Mann wrote:

Dear All,
I agree with each of Tom W's suggestions. Adopting them, by the way, brings us down to
738 words.
So pending any revised language from Keith/Malcolm in response to Michael O's comment on
paragraph 2, I'm putting out a last call for comments, sign-ons, etc...
Thanks,
mike
At 08:00 AM 10/14/2003 -0600, Tom Wigley wrote:

Some minor points ....
para. 2 -- should it be 'an' ensuing rather than 'the' ensuing?
para. 2 -- I still think 'each' (line 3) is unnecessary
para. 4 -- no comma after '(and globe)'
re boreholes, does the point about comparing late 20th century with a 'much longer
period' 1000 years ago help us? Given that the 1000 years ago data is highly lowpass
filtered, if one *did* have a series with a temporal resolution that allowed a
legitimate comparison, then the likelihood of a warmer interval 1000 years ago must be
higher.
In any event, the time scale issue will not be meaningful to most readers. The key point
is the data reliability/uncertainty. I would just say something like ...
".... taken into account. For times more than 500 years ago, uncertainties in the
borehole reconstructions preclude any useful quantitative comparison."
Finally, I would like the last para. retained, but I suggest shorter wording as ...
".... as indicating that SB03 misinterpreted and misrepresented the paleoclimatological
literature. The controversy ....".
My problem here is twofold. First, they really say nothing directly about 'mainstream
scientific opinion' (except that they clearly disagree with it). At issue is not the
mainstream opinion, but their interpretation of the literature and their illogical
conclusions. Second, they may have misrepresented the results of their work, but we do
not address this issue so it comes here as a non sequitur. In fact, just what such
'misrepresentation' consists of, and why it might be judged as 'misrepresentation' is a
subtle issue. Hence my revision -- which retains the word 'misrepresentation', but in a
different context.
Tom.
+++++++++++++++++++++++++++++++==
Michael E. Mann wrote:

Thanks Tim and Malcolm,
The latest round of suggestions were extremely helpful. I've accepted them w/ a few
minor tweaks (attached). We're at 765 words--I think AGU will let us get away w/ that...
So, comments from others?
Thanks,
mike
At 02:11 PM 10/14/2003 +0100, Tim Osborn wrote:

SO3 argue that borehole data provide a conflicting view of past temperature histories.
To the contrary, the borehole estimates for recent centuries shown in M03 may be
consistent with other estimates, provided consideration is given to statistical
uncertainties, spatial sampling and possible influences on the ground surface [e.g.,
snow cover changes--Beltrami and Kellman, 2003]. It is not meaningful to compare the
late 20th century with a much longer period 1000 years ago [Bradley et al., 2003],
especially given the acknowledged limitations [Pollack et al., 1998] of borehole data.

______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [4]mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137
[5]http://www.evsc.virginia.edu/faculty/people/mann.shtml

______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [6]mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137
[7]http://www.evsc.virginia.edu/faculty/people/mann.shtml

--
Caspar M. Ammann
National Center for Atmospheric Research
Climate and Global Dynamics Division - Paleoclimatology
Advanced Study Program
1850 Table Mesa Drive
Boulder, CO 80307-3000
email:
[8]ammann@ucar.edu
tel: 303-497-1705 fax: 303-497-1348


______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: [9]mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137
[10]http://www.evsc.virginia.edu/faculty/people/mann.shtml

--
Caspar M. Ammann
National Center for Atmospheric Research
Climate and Global Dynamics Division - Paleoclimatology
Advanced Study Program
1850 Table Mesa Drive
Boulder, CO 80307-3000
email:
[11]ammann@ucar.edu
tel: 303-497-1705 fax: 303-497-1348

______________________________________________________________
Professor Michael E. Mann
Department of Environmental Sciences, Clark Hall
University of Virginia
Charlottesville, VA 22903
_______________________________________________________________________
e-mail: mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137
[12]http://www.evsc.virginia.edu/faculty/people/mann.shtml

References

1. mailto:mem6u@virginia.edu
2. mailto:ammann@ucar.edu
3. mailto:mann@virginia.edu
4. mailto:mann@virginia.edu
5. http://www.evsc.virginia.edu/faculty/people/mann.shtml
6. mailto:mann@virginia.edu
7. http://www.evsc.virginia.edu/faculty/people/mann.shtml
8. mailto:ammann@ucar.edu
9. mailto:mann@virginia.edu
10. http://www.evsc.virginia.edu/faculty/people/mann.shtml
11. mailto:ammann@ucar.edu
12. http://www.evsc.virginia.edu/faculty/people/mann.shtml

No comments:

Post a Comment