Friday, May 25, 2012

4719.txt

date: Mon Jul 25 11:25:10 2005
from: Phil Jones <p.jonesatXYZxyz.ac.uk>
subject: Changes to 3.4 to accommodate Sherwood et al OK
to: Kevin Trenberth <trenbertatXYZxyzr.edu>

Kevin,
Changes to section 3.4.1.1/2/5 are all OK.
Phil
At 19:17 22/07/2005, you wrote:

Phil
Rumour has it that all three will be together. I have made changes in 3.4.1 and they
turn out to be non trivial:
3.4.1.1
I moved the Haimberger para to second last and added stuff:
A new development in approaches to improve radiosonde data has been to use the
bias-adjustments estimated during data assimilation into model-based reanalyses
(Haimberger, 2005). Despite the risk of contamination by other biased data in the
assimilation, or by model biases, the adjustments are found to agree with those
estimated by existing methods. In another major new development, Sherwood et al. (2005)
has found substantial changes in the diurnal cycle as measured by sondes that are almost
certainly a consequence of improved sensors, which have have become much smaller over
time, reducing the radiation effects. Hence relative to nighttime values, they find a
daytime warming of sonde temperatures prior to 1971 that is likely spurious and then a
daytime cooling, especially from 1979 to 1997 during the satellite era, that is also
spurious. Thus there is likely a spurious downward trend in sonde temperature records
throughout the atmosphere after 1979 of order 0.1�C globally: the assessed spurious
cooling is greatest in the tropics of 0.16 K decade^1 for the 850 to 300 hPa layer, and
least in the NH extratropics of 0.04 K decade^-1.
End of 3.4.1.2 now reads:
While comparisons of radiosonde station data with collocated satellite data (Christy and
Norris, 2004) suggest that the median trends of radiosonde temperatures in the
troposphere are very close to UAH trends and a little less than RSS trends, comparisons
of trends at individual radiosonde sites vary and root mean square differences of UAH
satellite data with radiosondes are substantial (Hurrell et al., 2000). Moreover,
radiosonde data contain diurnal cycle influences (Sherwood et al., 2005) that lead to
spurious cooling throughout the atmosphere from 1979 to 1997, and residual spurious
downward jumps (Randel and Wu, 2005), so that they are compromised by multiple problems
(Section 3.4.1.1 and Appendix 3.A.5.1). In the stratosphere, radiosonde trends are more
negative than both MSU retrievals, especially when compared with RSS, and this too is
likely due to changes in sondes (Randel and Wu, 2005).
In 3.4.1.5 I added one sentence at end of para:
In the tropics, the theoretically expected amplification of temperature perturbations
with height is borne out in interannual fluctuations (ENSO) in radiosondes, RSS and with
models (Santer et al., 2005), and only the radiosonde records are at odds for trends.
If the latter were corrected for radiation effects (Sherwood, et al. 2005), then they
too show increased warming with altitude.
Kevin
Phil Jones wrote:

Kevin,

Whilst in Exeter, I got this from Peter Thorne (who is reviewing it for
Science).
I suspect we should be referring to it, just as an addition to the Randel and Wu
paper. It would seem that Bill is aware of this. Maybe you've already seen this.
Peter went on about not passing this on to anyone else and also what
Ch 3 should be concluding about the whole LT issue and what CCSP says.
I felt what he was saying was far too strong, so won't go into it. He is my
ex-student - I hope the situation won't go as far as you have with one of your
ex-students!
CCSP should be available from Aug 15 publicly until Sept 30. Then they
have a meting in mid-Oct to finalize everything and all will be printed by Oct 31 !
They've been told they can't change anything once they leave O'Hare at the
end of the meeting.
The attached paper is tentatively accepted, as is Santer et al. Peter didn't
know about Mears and Wentz. The plan is for Science to put all three out
together asap, but this is also confidential.
Most of the chapters for CCSP are coming along well - except for the Pielke
one, now there's a surprise. He's not happy with the Peterson paper on E. Colorado.
I'll email again later today with some more on the FOD. Downloaded the latest
draft and figs. First I need to get comments back on Brohan et al. so that can be
submitted.
Cheers
Phil
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 [1]p.jones@uea.ac.uk
NR4 7TJ
UK
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--
****************
Kevin E. Trenberth e-mail: [2]trenbert@ucar.edu
Climate Analysis Section, NCAR [3]www.cgd.ucar.edu/cas/
P. O. Box 3000, (303) 497 1318
Boulder, CO 80307 (303) 497 1333 (fax)

Street address: 1850 Table Mesa Drive, Boulder, CO 80303

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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