Tuesday, December 13, 2011

1101133749.txt

From: Phil Jones <p.jones@uea.ac.uk>
To: Adrian.Simmons@ecmwf.int, santer1@llnl.gov
Subject: Fwd: Re: K&C (fwd)
Date: Mon Nov 22 09:29:09 2004
Cc: wigley@ucar.edu

Adrian and Ben,
Roger Pielke did send this to me over the weekend, so he's being honest
in one respect. I still think he's reading far too much into NCEP1. The bottom panel
of their Fig1 shows both CRU and GHCN (-ERA40) having no difference over the period
from the late 1960s. If the obs assimilated before 1967 (even in the US) were improved,
the apparent drop before might disappear.
Cheers
Phil

Date: Fri, 19 Nov 2004 18:35:58 -0700 (MST)
From: Roger Pielke <pielke@atmos.colostate.edu>
To: p.jones@uea.ac.uk
cc: wigley@cgd.ucar.edu
Subject: Re: K&C (fwd)
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Phil-
FYI; thank you for sharing your paper. I have circulated the attached to
our CCSP Committee with the permission of Eugenia and Ming, and want to
also share with you.
The conclusion from my own work with the NCEP reanalysis is that it is
appropriate for trend assessments if integrated metrics are used
(thickness for example), and for regions where the regional trend signal
is quite large. We have published on both of this issues. One value-added
of reanalyses is that since the winds are monitored independently of the
temperatures, they provide information on the horizontal layer averaged
temperatures in the mid- and high-latitudes, which helps adjust, to some
extent, biases in the temperatures.
Also, as we have shown with regional data (e.g. Florida) and others have
shown elsewhere (e.g. Andy Pitman for Australia) there is a clear land use
change signal on surface temperature. This provides independent evidence
that the Kalnay and Cai results should be expected.
Roger
--
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Roger A. Pielke, Sr., Professor and State Climatologist
1371 Campus Delivery, Department Atmospheric Science,
Colorado State University, Fort Collins, CO 80523-1371,
Phone: 970-491-8293/Fax: 970-491-3314, Email: pielke@atmos.colostate.edu
VISIT OUR WEBSITES AT: [1]http://blue.atmos.colostate.edu/
and [2]http://climate.atmos.colostate.edu
---------- Forwarded message ----------
Date: Fri, 19 Nov 2004 11:04:42 -0700 (MST)
From: Roger Pielke <pielke@atmos.colostate.edu>
To: _NESDIS NCDC CCSP Temp Trends Lead Authors
<CCSPTempTrendAuthors.NCDC@noaa.gov>, chris.folland@metoffice.gov.uk,
peter.thorne@metoffice.gov.uk
Cc: Eugenia Kalnay <ekalnay@atmos.umd.edu>, Ming Cai <cai@huey.met.fsu.edu>
Subject: Re: K&C (fwd)
Resent-Date: Fri, 19 Nov 2004 11:05:15 -0700
Resent-From: CCSPTempTrendAuthors.NCDC@noaa.gov
Hi All
I requested to Ming Cai and Eugenia Kalnay that they respond to the
comments regarding their work. The response is forwarded to you in this
e-mail.
This debate, of course, should really take place in the literature. There
has been, however, in my view an unfortunate change over time where
reviewers who disagree with already published work recommend rejection of
subsequent work rather than letting the community view and assess the
different perspectives on a science issue. Our report has to make sure it
is inclusive, in order to avoid this pitfall.
An unbiased discussion of the K&C results, and ways to resolve the
disagreement through hypothesis testing, should be included in the
appropriate chapters.
Roger
--
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Roger A. Pielke, Sr., Professor and State Climatologist
1371 Campus Delivery, Department Atmospheric Science,
Colorado State University, Fort Collins, CO 80523-1371,
Phone: 970-491-8293/Fax: 970-491-3314, Email: pielke@atmos.colostate.edu
VISIT OUR WEBSITES AT: [3]http://blue.atmos.colostate.edu/
and [4]http://climate.atmos.colostate.edu
---------- Forwarded message ----------
Date: Fri, 19 Nov 2004 12:16:27 -0500
From: cai <cai@met.fsu.edu>
To: Roger Pielke <pielke@atmos.colostate.edu>
Cc: Ming Cai <cai@met.fsu.edu>, Y. K. Lim <yklim@met.fsu.edu>,
Eugenia Kalnay <ekalnay@atmos.umd.edu>
Subject: Re: K&C
Dear Roger,
Attached is the preliminary summary report on our recent work on the
estimate of land-use-change climate impact using the reanalysis. Very
fortunately, we had secured a one-year funding from NSF starting last
August. Despite a short time period, we have already produced sufficient
results to confirm the robustness of our original work using different
datasets that have the state-of-art quality.
Here I just want to add one more comment about Simmons et al. paper.
Basically, they claimed that the difference between the ERA40 and CRU is
very small and therefore, our method is not applicable if the reanalysis
is as good as the ERA40. There are two things that are incorrect in their
claims. First of all, if the reanalysis were made to be exactly the same
as the observations, by definition, there would be no difference between
reanalysis and the surface observations. Since the ERA40 was obtained by
directly assimilating the CRU surface observations whereas the NNR didn't
use any surface temp. observation, it is natural to expect that the
difference between the surface observation and ERA40 is small. Second,
Simmons et al. manually reduces the difference between the ERA40 and CRU
by setting the mean difference between the ERA40 and CRU from 1987 to 2001
be ZERO. As a result, the difference "LOOKs" very small in recent years.
However, the difference from 1961 to 1985 has to be larger (otherwise,
they would make an error in their plot). In other words, by doing so, the
gap between the ERA40 and CRU appears decreasing in time rather increasing
in time as shown in KC and in the new figure 1 in the attached file (which
is the same as Simmons et al. paper except we reset the 1960-70 to be zero
in order to see how the POSITIVE gap increases in time). If we closely
examine their figures, we will see by applying their treatment, the gap
between CRU and reanalysis is a NEGATIVE one (e.g., CRU is below ERA40
from 1960 to 1980) and such a NEGATIVE gap decrease in time is equivalent
to that the POSITIVE gap increases in time as found in KC from the NNR
data (e.g., the CRU becomes more above the ERA40). So Simmons et al's
results actually CONFIRM our findings rather discredit our finding. We
actually reproduced Simmons et al calculations and confirm that their
results are correct (see the second attached figure, which is identical to
Fig.1 in our preliminary report except the NEGATIVE gap is used and 1-year
running mean was applied as in Simmons et al). But their interpretations
are incorrect.
I appreciate if you could also forward the email to the CCSP authors.
Let me know if you want to me to reply to Tom and CCSP co-authors
directly.
Regards.
Ming
The report:
The replica of one of the key figures in Simmons et al.
On Nov 18, 2004, at 4:53 PM, Roger Pielke wrote:

Tom-
Since we have not seen the paper, we cannot make any judgements on the
robustness of that paper in showing that the Kalnay and Cai work is
"flawed". I expect to have a summary by Eugenia and Ming tomorrow,
however, which will address the published concerns on their work, and
will
forward to the Committee. Please forward us a copy of the Simmons et al
paper.
I also would like a response to my MWR Florida paper where we
specifically show the dominant role of documented land use change in
peninsular Florida in the 20th century on July-August surface air
temperature change. Or Andy Pitman's work who shows a major effect on
temperature trends in south-western Australia due to land use change.
This work, and others like it, support the conclusions of Kalnay and
Cai
on a major role of land surface processes on surface temperature
trends.
How do you reconcile those independent conclusions with the paper you
list above?
Roger
--
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++
Roger A. Pielke, Sr., Professor and State Climatologist
1371 Campus Delivery, Department Atmospheric Science,
Colorado State University, Fort Collins, CO 80523-1371,
Phone: 970-491-8293/Fax: 970-491-3314, Email:
pielke@atmos.colostate.edu
VISIT OUR WEBSITES AT: [5]http://blue.atmos.colostate.edu/
and [6]http://climate.atmos.colostate.edu
On Thu, 18 Nov 2004, Tom Wigley wrote:

Date: Thu, 18 Nov 2004 14:28:16 -0700
From: Tom Wigley <wigley@cgd.ucar.edu>
To: CCSP Authors <CCSPTempTrendAuthors.NCDC@noaa.gov>
Subject: K&C
Resent-Date: Thu, 18 Nov 2004 14:28:17 -0700
Resent-From: CCSPTempTrendAuthors.NCDC@noaa.gov
Folks,
Roger makes the point that there is no comprehensive assessment of
this
paper.
There is ... It is in a paper that has, I believe, been accepted by
JGR
atmospheres.
A.J. Simmons, P.D.Jones, et al. "Comparison of trends and
low-frequency
variability in CRU,
ERA-40 and NCEP/NCAR".
I think the conclusion is that the K&C paper *is* flawed.
Tom.

Ming Cai
Associate Professor
Department of Meteorology
Florida State University, Tallahassee, FL 32036
Email: cai@met.fsu.edu, cai@csit.fsu.edu
Phone: (850)-645-1551, FAX: (850)-644-9642

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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References

1. http://blue.atmos.colostate.edu/
2. http://climate.atmos.colostate.edu/
3. http://blue.atmos.colostate.edu/
4. http://climate.atmos.colostate.edu/
5. http://blue.atmos.colostate.edu/
6. http://climate.atmos.colostate.edu/

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