date: Tue, 9 Mar 2004 13:01:04 -0800
from: Richard Somerville <rsomerville@ucsd.edu>
subject: Re: REQUEST FOR INFORMATION ON CLIMATE CHANGE AND HUMAN
to: Chick Keller <cfk@lanl.gov>, Kevin Trenberth <trenbert@cgd.ucar.edu>, Tom Wigley <wigley@cgd.ucar.edu>, "Howard Hanson, LDRD" <hph@lanl.gov>, "James E. Hansen" <jhansen@giss.nasa.gov>, Michael Schlesinger <schlesin@atmos.uiuc.edu>, Phil Jones <p.jones@uea.ac.uk>, Thomas R Karl <Thomas.R.Karl@noaa.gov>, Mike MacCracken <mmaccrac@comcast.net>, Ben Santer <santer1@llnl.gov>, Tom Crowley <tcrowley@duke.edu>, <thompson.4@osu.edu>, rbradley@geo.umass.edu, mhughes@ltrr.arizona.edu, Keith Briffa <k.briffa@uea.ac.uk>, Tim Osborn <t.osborn@uea.ac.uk>

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Hi Chick and friends,

Good to hear from you, Chick.  I'm busy, like all of us, and 
responding to Singer is not my cup of tea, so I'm glad you and others 
are willing.  I hate to be in the same room with him, frankly.  He's 
a third-rate scientist and is ethically challenged, to say the least.

 From others on your email list, I am sure you will receive tons of 
useful information.  However, I think your entire basic strategy for 
confronting Singer might not be optimal.  Sometimes the most pressing 
issues in the research community, or the most interesting questions 
scientifically, are not necessarily the best ways to carry on the 
public conversation.  I am thinking in particular of your statement:

"Perhaps the most important is that satellites don't show much 
warming since 1979 and disagree substantially with the surface 
record, which must then be incorrect.  Were we able to resolve this 
conundrum, I think most of the other objections to human generated 
climate change would lose their credibility."

For what it's worth,  here's my take on your approach.  I 
respectfully disagree with you that hammering away on reconciling the 
MSU data with radiosonde and surface data is the right way to go in 
dealing with the Fred Singers of the world.  Even though much of the 
differences may now be apparently explained, it's still a terribly 
messy job.  The satellite system wasn't designed to measure 
tropospheric temperatures, the calibration and orbital decay and 
retrieval algorithm and all the other technical issues are ugly, and 
nobody knows how much the lower stratospheric cooling ought to have 
infected the upper troposphere, among other points one might make.

No matter what one does on trying to make the MSU data tell us a 
clean story, there are remaining serious uncertainties.   That's 
basically what the NAS/NRC study chaired by Mike Wallace concluded, 
and it's still true, in my view.  Plus the data record is so short. 
In addition, as you say, you are retired, and research on these 
things is not what you have first-person experience with, so when you 
try to study up on the latest published results, you're at a 
disadvantage compared with the Singers of the world, whose full-time 
job is to cherry-pick the literature for evidence to support their 
preconceived positions.

One of the tactics of the skeptics is to create the impression among 
nonscientists, especially journalists, that the entire science of 
climate change rests on the flimsy foundation of one or two lines of 
evidence, so that casting doubt on that foundation ought to bring 
down the entire structure.  For temperature, that approach is clearly 
behind the attacks on the "hockey stick" curve over the last 1,000 
years or the satellite vs. in situ differences over the last 25 
years.  Refuting the errors of the papers by Soon and Baliunas or by 
McIntyre and Mckitrick doesn't faze these people.  They just shift 
their ground and produce another erroneous attack.  Their goal is not 
to advance the science, but to perpetuate the appearance of 
controversy and doubt.

I don't think the skeptics should be allowed to choose the 
battlefield, and I certainly don't think the issue of whether 
anthropogenic influences are a serious concern should be settled by 
looking at any single data set.  I do think the IPCC TAR was right to 
stress that you simply can't plausibly make GCMs replicate the 
instrumental record without including GHGs (and aerosols).  I also 
think the recent AGU and AMS public statements, which you will 
doubtless find on their web sites, are right on target.  Many of us 
were pleasantly surprised that our leading scientific societies have 
recently adopted such strong statements as to the reality and 
seriousness of anthropogenic climate change.  There really is a 
scientific consensus, and it cannot be refuted or disproved by 
attacking any single data set.

I also think people need to come to understand that the scientific 
uncertainties work both ways.  We don't understand cloud feedbacks. 
We don't understand air-sea interactions.  We don't understand 
aerosol indirect effects.  The list is long.  Singer will say that 
uncertainties like these mean models lack veracity and can safely be 
ignored.  What seems highly unlikely to me is that each of these 
uncertainties is going to make the climate system more robust against 
change.  It is just as likely a priori that a poorly understood bit 
of physics might be a positive as a negative feedback.  Meanwhile, 
the climate system overall is in fact behaving in a manner consistent 
with the GCM predictions.  I have often wondered how our medical 
colleagues manage to escape the trap of having their entire science 
dismissed because there are uncured diseases and other remaining 
uncertainties.  Maybe we can learn from the physicians.

People on airplanes, when they find out what I do for a living, 
usually ask me if I "believe in" global warming.  It's not religion, 
of course.  What I actually tend to believe in, if they really wanted 
to try to understand, is quantum mechanics.  CO2 and CH4 and all 
those other interesting trace gases have more than two atoms, and 
that fact simply has inescapable consequences.  You just can't keep 
adding those GHG molecules indefinitely without making the atmosphere 
significantly more opaque in the IR.   The "debates" in the reputable 
research community are all quantitative.  If skeptics don't worry 
about doubling, they ought to be pressed to tell us why they are 
unconcerned about tripling or quadrupling or worse.  That's where the 
planet is headed.  The fact that remote sensing and model building 
are hard work, and that much remains to be done, shouldn't be allowed 
to obscure the basic obvious facts.

Bonne chance et bon courage,

Richard
-- 
Prof. Richard C. J. Somerville
Scripps Institution of Oceanography
University of California, San Diego
9500 Gilman Drive, Dept. 0224
La Jolla, CA 92093-0224,USA

Phone: 858 534-4644
Fax: 858 534-8561

http://myprofile.cos.com/somerv96
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