Thursday, June 7, 2012

4910.txt

date: Wed Jul 6 08:57:41 2005
from: Phil Jones <p.jonesatXYZxyz.ac.uk>
subject: Fwd: Misc
to: n.nichollsatXYZxyz.gov.au

Neville,
Here's an email from John, with the trend from his latest version in. Also
has trends for RATPAC and HadAT2. If you can stress in your talks that it is
more likely the sondes are wrong - at least as a group. Some may be OK
individually. The tropical ones are the key, but it is these that least is know
about except for a few regions. The sondes clearly show too much cooling in
the stratosphere (when compared to MSU4), and I reckon this must
also affect their upper troposphere trends as well. So, John may be putting
too much faith in them wrt agreement with UAH.
Happy for you to use the figure, if you don't pass on to anyone else. Watch
out for Science though and the Mears/Wentz paper if it ever comes out.
Also, do point out that looking at surface trends from 1998 isn't very clever.
Cheers
Phil

Date: Tue, 05 Jul 2005 07:59:51 -0500
From: John Christy <john.christyatXYZxyztc.uah.edu>
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To: Phil Jones <p.jonesatXYZxyz.ac.uk>
Subject: Misc
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Hi Phil:
I've been getting round-about versions of rumors concerning our newly adjusted version
5.2 LT dataset. I believe I had indicated earlier to you that the correction was within
our published margin of error. In any case here are the numbers that describe various
aspects of v5.2
1979-2004
Global Trend +0.115 UAH, +0.125 RATPAC and +0.137 HadAT (note, when subsampled for the
same latitudes in which sonde observations are available, UAH and HadAT are almost
exactly the same.)
Update of site by site comparison of UAH LT 5.2 and SH radiosondes from Christy and
Norris 2004:
All 87 SH stations, no adjustments Raobs + 0.028 UAH +0.040
74 best sites with adjustments Raobs +0.030 UAH +0.054
These SH changes from the original publication were very minor because most stations
were outside the tropics where the diurnal error had essentially no impact.
A paper by Sherwood claims that Day minus Night is a legitimate way to go about looking
at sonde problems. The real problem though is that Day minus Night is only an indicator
of a sonde change, it does not determine the change itself. Most notorious is the
Philipps Mark III to Vaisala RS-80 where the night warmed by about 0.3 C and the day by
a little bit less, which means the Day minus Night reveals a negative shift when in fact
both ob times have a significant positive shift (these sondes form a signifciant part of
the LKS dataset). Similar results occur for US VIZ mini-art 2 to Micro-art software in
1990.
I have many other sone comparisons, and all are more consistent with the UAH trends more
than RSS and certainly VG. Indeed, I was curious to see that your name was on VG's
latest paper. I wish I had time to fill you in on why the addition of the non-linear
terms is a red herring (both UAH and RSS have performed the calculations with and
without the non-linear terms with no impact on the trends) and why the latitudinal
difference for calculating the coefficients leads one astray. I'm a little nervous now
that you may have a "dog in this fight" as we say in Alabama while writing up the IPCC.
I expect my sonde comparisons to be included in the IPCC and I will have further results
demonstrating the problems with the Day minus Night technique within a few months.
I've lots to do now. Thanks for listening.
John C.
--
************************************************************
John R. Christy
Director, Earth System Science Center voice: 256-961-7763
Professor, Atmospheric Science fax: 256-961-7751
Alabama State Climatologist
University of Alabama in Huntsville
[1]http://www.nsstc.uah.edu/atmos/christy.html
Mail: ESSC-Cramer Hall/University of Alabama in Huntsville, Huntsville AL 35899
Express: Cramer Hall/ESSC, 320 Sparkman Dr., Huntsville AL 35805

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.jonesatXYZxyz.ac.uk
NR4 7TJ
UK
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