Op-ed on policy and probability
James Annan
http://www.courant.com/news/opinion/op_ed/hc-yohe0630.artjun30,0,7395459.story
James
william
James Annan wrote:
> An interesting comment:
>
> http://www.courant.com/news/opinion/op_ed/hc-yohe0630.artjun30,0,7395459.story
Clearly not that interesting :-)
Anyway, yes indeed, if you are going to react to 1% events there will
be a lot of things to react to. I suspect that the 1% doctrine is more
an excuse to do things for little justification, and won't be extended
to inconvenient areas.
-W.
Michael Tobis
ill-specified result in a complex system is really a subjectrive
measure. Should we respond to a *plausible* 1% chance? How plausible?
A 1 % chance of a 1 % chance? I'm not being entirely facetious here.
Steinn Sigurdsson used to point out on sci.env that we can't have a
proportional response to more than infinitesimal chances of infinite
damage.
The fact is that we have a significant number of significant threats
to cope with. The strategy for dealing with any one of them in
isolation is probably different than the strategy for dealing with the
whole cluster of them.
Climate change considered in isolation is a big problem, but climate
changte considered as a component of other global scale problems
(water, food, ecosystems, epidemics, and stupid stubborn hostility
based on race, language and superstition) is bigger still.
I think the article asks the right question in a sense, but what we're
looking for is not a comparison of various threats. It's a way to
maximizing the probability of getting through the population crunch
of the next couple of centuries without civilization collapsing. We
may disagree on whether that is likely without necessarily impacting
whether we agree on the best strategy.
mt
Coby Beck
news:<1152443607.2...@h48g2000cwc.googlegroups.com>...
>
>
> James Annan wrote:
> > An interesting comment:
> >
> >
http://www.courant.com/news/opinion/op_ed/hc-yohe0630.artjun30,0,7395459.sto
ry
>
> Clearly not that interesting :-)
>
> Anyway, yes indeed, if you are going to react to 1% events there will
> be a lot of things to react to. I suspect that the 1% doctrine is more
> an excuse to do things for little justification, and won't be extended
> to inconvenient areas.
Clearly. The list of one percent threats in the national security arena
must be quite long, and easily extendable. So just pick however you want to
preemptively attack based on all those other good reasons...
Coby
James Annan
It's important to also realise that the 1% (or any other probability) is
fundamentally nothing more than a statement of someone's belief. Of
course, that belief can be more or less credible based on the evidence
available, but ultimately it contains a subjective element. So there is
little to stop people talking up the probabilities of things they want
to act on, and talking down the probabilities of others.
I think most scientists are rather poor at expressing this subjectivity
clearly, and climate science is no exception.
James
Roger Coppock
ignoring steady state changes, this is a major
mistake.
I don't know how to calculate the probability of
abrupt climate changes, nor have I seen many
reliable reports of such calculations agreeing on
similar numbers. I do know that the probability
that the Earth's global mean surface temperature
is slowly rising is roughly 20 nines, or
99.999999999999999999%. That is well above
1%, and that clearly should be a policy concern.
Michael Tobis
Because there are known low frequency phenomena in the atmosphere the
purely statistical probability (leaving out physical arguments) that
the observations are distinct from a null hypothesis of no sustained
warming, while surely quite high, is nowhere near as high as is
obtained from assuming independent samples.
Also, just because the probability of an event is greater than 1% is
not even advanced as a sufficient argument for responding to it. It
also has to be a condition that is obviously dangerous.
Now, I believe it is, but you didn't assert that. So your argument
as presented isn't especially compelling.
mt
William M Connolley
On Thu, 13 Jul 2006, Michael Tobis wrote:
> I believe your calculations presume independent samples.
>
> > I do know that the probability
> > that the Earth's global mean surface temperature
> > is slowly rising is roughly 20 nines, or
> > 99.999999999999999999%. That is well above
> > 1%, and that clearly should be a policy concern.
OK, this has come up before, and Roger has resisted my argument about
autocorrelation affecting the sig levels. So, here is a simple example. First
the results: this is generating a random (and hence, "really" no trend) series
200 times, with a given level of autocorrelation "a", and finding out how many
of the series are assessed to have a stat sig trend. If all the stats are
working properly, then 10% should be ("falsely") judged to have a trend (since
I'm using 90% sig level). So:
a=0
wmc> .run indep
13.0000% were judged significant
wmc> .run indep
9.50000% were judged significant
wmc> .run indep
11.0000% were judged significant
a=0.5
wmc> .run indep
34.0000% were judged significant
wmc> .run indep
35.5000% were judged significant
wmc> .run indep
36.0000% were judged significant
a=0.75
wmc> .run indep
54.5000% were judged significant
wmc> .run indep
54.0000% were judged significant
wmc> .run indep
50.5000% were judged significant
(AR1 means that x_i+1 = x_i * a + e_i; e_i being random noise).
So: a=0 gets you 10% (close enough...); and we see that as a increases more and
more series are "falsely" judged to be sig. I'm sure this can be done
analytically too (james? michael?).
Code below:
;
; Pro to demonstrate how autocorrelation skews statistics of trend
;
n=200 ; Number of realisations
l=100 ; Length of each realisation
a=0.750 ; Autocorrelation
c=0
p=0.10 ; 0.10 = 90% (two-tailed) sig test
for i=0,n-1 do begin
; Generate an AR1 series - ie, autocorrelation of "a"
s=ar1(a,l)
; Regress the series, and decide if the trend is sig (1) or not (0)
r=reg_explain(/quiet,pp_regress(s,/arr),prob=p)
; Count those that are sig
c=c+r
endfor
; How many are judged sig? Should be 10% if all has gone well
print,c/float(n)*100,'% were judged significant'
end
William M Connolley | w...@bas.ac.uk | http://www.antarctica.ac.uk/met/wmc/
Climate Modeller, British Antarctic Survey | (01223) 221479
If I haven't seen further, it's because giants were standing on my shoulders
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records management system.
Raymond Arritt
> I believe your calculations presume independent samples.
>
> Because there are known low frequency phenomena in the atmosphere the
> purely statistical probability (leaving out physical arguments) that
> the observations are distinct from a null hypothesis of no sustained
> warming, while surely quite high, is nowhere near as high as is
> obtained from assuming independent samples.
More broadly, please see "The Insignificance of Significance Testing" by
Neville Nicholls, Bulletin of the American Meteorological Society, Vol.
82, No. 5, pp. 981–986 (2001).
Public access to BAMS is free. Go to:
http://ams.allenpress.com/amsonline/?request=get-toc&issn=1520-0477&volume=82&issue=5
and scroll down (under "commentary and analysis").
--
Raymond W. Arritt tel +1-515-294-9870
Professor, Department of Agronomy fax +1-515-294-2619
3010 Agronomy Hall, Iowa State University, Ames, Iowa 50011 USA
http://www.mesoscale.iastate.edu Unit #02582 (TINLC)
----------------------------------------------------------------
When in doubt, keep it simple. -- Jack Casady
Roger Coppock
There is more than a single data set showing
a warming world. Their summed significance
of these independent measurements is quite
high, well over 20 nines. Please see:
The global ground weather station network shows warming:
http://members.cox.net/rcoppock/Global%20Mean%20Temp.jpg
The balloon record shows this same warming:
http://members.cox.net/rcoppock/Angell-Balloon.jpg
The satellite record, in all its current interpretations, shows
that the air near the surface is warming too:
The URL below is one of the more conservative records from the
University of Alabama at Huntsville.
http://members.cox.net/rcoppock/UAH-MSU.jpg
The record of sea ice melting:
http://nsidc.org/news/press/20050928_trendscontinue.html
The glacier retreat record:
http://nsidc.org/sotc/glacier_balance.html
The bore hole record:
http://www.ncdc.noaa.gov/paleo/globalwarming/pollack.html
Rising sea level:
http://sealevel.colorado.edu/
http://en.wikipedia.org/wiki/Image:Recent_Sea_Level_Rise.png
Michael Tobis
contrary. "In probability theory, to say that two events are
independent intuitively means that the occurrence of one event makes
it neither more nor less probable that the other occurs." (wikipedia)
I'm not saying it isn't warming. I'm saying your numbers don't mean
anything. Getting statistics right is a very subtle thing sometimes.
It is also overvalued in global change discussions in my opinion. You
will note that statistical climatologists tend to be much less on the
alarmist side than physical climatologists and paleoclimatologists.
We can't fix this by doing bad statistics, though. We need *more*
subtle statistics than are common rather than more simpleminded ones
to get useful numbers. The statistical methods need to in some sense
know something about the physics.
mt
James Annan
> More broadly, please see "The Insignificance of Significance Testing" by
> Neville Nicholls, Bulletin of the American Meteorological Society, Vol.
> 82, No. 5, pp. 981–986 (2001).
>
> Public access to BAMS is free. Go to:
>
> http://ams.allenpress.com/amsonline/?request=get-toc&issn=1520-0477&volume=82&issue=5
>
> and scroll down (under "commentary and analysis").
>
This paper repeats much of the well-known (but frequently ignored)
problems with statistical hypothesis testing. It should be required
reading for all climate scientists.
However, it unfortunately drops a clanger of its own.
It recommends generating confidence intervals (rather than just a
p-value for the null hypothesis):
James Annan
Sigh. Dog ate my homework. Try again.
"The reporting of confidence intervals would allow readers to address
the question 'Given these data and the correlation calculted with them,
what is the probability that H0 is true?'".
However, this is false, and this error (equating a frequentist
confidence interval with a bayesian credible interval) is equally as
pernicious as the simple prosecutor's fallacy that Nicholls rails
against. Indeed, it is essentially the same error, of interpreting
P(D|H) as P(H|D)! This mistake seems well-nigh ubiquitous in climate
science, eg the whole of the detection and attribution field (chapter 12
in the IPCC TAR) falls into this trap, and MBH's "likely the warmest"
does the same. I noted the same thing in a recent D&A paper (which is
co-authored by some of the most prominent names in the field) a few days
ago and am awaiting their explanation/excuses...
Nicholls cites Wilks (Statistical methods in the atmospheric sciences)
for confidence interval calculation, but Wilks makes the same error.
Unfortunately, I think my chances of persuading the climate science
community of the error is rather slim given such authority lined up in
opposition. Nevertheless, it is trivial to generate confidence intervals
that are entirely valid and correct in the frequentist sense, but which
cannot possibly contain an unknown parameter with the specified
probability.
Of course, I'm happy to acknowledge my own fallibility and would be
interested to hear of any arguments to the contrary...
James
Roger Coppock
this post and taken it to statistical nowhere. A result
worthy of the fossil fools on alt.global-warming.
Raymond Arritt
Sorry if you're offended but that's how it goes in science. If you
misuse a technique then you can expect to be called to account. The
same standards have to apply whether you're a sincere environmentalist,
a "fossil fool", a scientific colleague, or a former Vice President. We
can't give someone a pass because we agree with their views.
Detecting errors and discussing ways to avoid them in the future is
essential to science, as is willingness to learn from constructive
criticism.
--
Raymond W. Arritt tel +1-515-294-9870
Professor, Department of Agronomy fax +1-515-294-2619
Iowa State University, 3010 Agronomy Hall, Ames, Iowa 50011 USA
http://www.mesoscale.iastate.edu Unit #02582 (TINLC)
------------------------------------------------------------
"Draw a straight line and follow it."
-- LaMonte Young, Composition 1960 No. 10
Roger Coppock
a level playing field, without the obvious censorship of the
moderators of this newsgroup. Perhaps we can find an
open forum for the discussion of the topic of this thread
too. Until then, . . .
William M Connolley
I suggest you start by pointing out what is wrong with
then
-W.
Robert A. Rohde
Michael Tobis wrote:
<snip>
> It is also overvalued in global change discussions in my opinion. You
> will note that statistical climatologists tend to be much less on the
> alarmist side than physical climatologists and paleoclimatologists.
<snip>
That's an interesting comment. Actually, most of the
paleoclimatologists I've met don't tend to be very concerned about
global warming. Of course, maybe if your business is studying ice
ages, then global warming doesn't seem so troubling.
On the other hand, I also know one active paleoclimate researcher who
thinks Micheal Crichton "gets it" and everyone should read State of
Fear.
-Robert
Eric Swanson
[cut]
> That's an interesting comment. Actually, most of the
> paleoclimatologists I've met don't tend to be very concerned about
> global warming. Of course, maybe if your business is studying ice
> ages, then global warming doesn't seem so troubling.
>
> On the other hand, I also know one active paleoclimate researcher who
> thinks Micheal Crichton "gets it" and everyone should read State of
> Fear.
Of course, over relatively long periods, there have been major climate
changes, such as the Ice Ages you mention. Forecasts suggest an
eventual return to such conditions, but perhaps not for several
thousand years. But, today's changes don't appear to have any analog
over the past few million years, so the paleo people really don't have
much to be complacent about.
While I've not read thru Micheal Crichton's book, I did look at the
references used to support his claims. I found several errors, such as
his use of the old Christy and Spencer MSU satellite data as "proof"
that there is no warming. That has all changed over the past few
years, which should be clear to anyone who has followed the discussion
about the satellite analysis.
For example, see the U.S. CCSP report found here:
http://www.climatescience.gov/Library/sap/sap1-1/finalreport/default.htm
As a matter of curiosity, would you identify the "paleoclimate
researcher" you mentioned in your post??
Michael Tobis
of C, Purdue, Wisconsin) and I'd say they are uniformly either
IPCC-centrist or on the cassandra side of the cassandra/polyanna scale
on anthro climate change.
In my observation it's the statisticians that seem the most blase,
especially the old-school statistical climatology types, who would
include the likes of Reid Bryson, Bill Gray, and even Pat Michaels
based on his PhD thesis, which you can see in the department library
at U Wisconsin-Madison if you're so inclined.
I think that is because they apply their assumption (everything is
cyclic) to get their analyses, and then circularly conclude that we
must be in a cycle.
Von Storch is much more sophisticated than that, and seems to be a
real statistician, but even he, and our own James, appear to be a
little on the relaxed-of-center side, though not as much as the less
mathematically sophisticated of the statistical crowd.
mt
James Annan
James Annan wrote:
> James Annan wrote:
> Nicholls cites Wilks (Statistical methods in the atmospheric sciences)
> for confidence interval calculation, but Wilks makes the same error.
> Unfortunately, I think my chances of persuading the climate science
> community of the error is rather slim given such authority lined up in
> opposition.
I'm pleased to be able to report that Prof Wilks replied promptly to
the email I sent him, agreeing with my point, and says that the latest
edition of his book has already been improved in this respect.
James
Robert A. Rohde
> As a matter of curiosity, would you identify the "paleoclimate
> researcher" you mentioned in your post??
Sorry, no. He's a closet skeptic that I've closely interacted with in
the past, but not someone that is publicly known for a skeptical view.
Out of respect for his privacy, I am not going to identify him here.
However, knowing him does make me wonder how many other climate
researchers are skeptical of global warming (or aspects thereof) but
are only willing say so in private.
-Robert
Eric Swanson
Robert A. Rohde wrote:
> Eric Swanson wrote:
> > As a matter of curiosity, would you identify the "paleoclimate
> > researcher" you mentioned in your post??
>
> Sorry, no. He's a closet skeptic that I've closely interacted with in
> the past, but not someone that is publicly known for a skeptical view.
> Out of respect for his privacy, I am not going to identify him here.
Sorry, but most scientists are skeptics by nature. A good scientist
must ALWAYS be ready to question the accepted explanations, else how
could he/she ever come up with new and different ideas and theories?
Since you won't give a name, would you give a summary of his
reasoning?
Michael Tobis
didactically so the rest of us can get it?
mt
James Annan
Michael Tobis wrote:
>
> That's great! Now how about if you explain it a little more
> didactically so the rest of us can get it?
It's probably a bit long and tedious to post here in all its tedium, but I've expanded my jihad (:-), see the comment) into an as-yet-incomplete series of blog posts starting with:
<http://julesandjames.blogspot.com/2006/07/more-on-detection-attribution-and.html>
I'm about to issue the full fatwa :-)
If that is too stodgy, IMO the most immediately compelling illustration is simply to note that when measuring a non-negative value (like mass, or speed, or energy) then a confidence interval which does not exclude zero - which may arise very naturally if measurements are inaccurate - does not in any way imply a belief that the value is actually negative with non-zero probability!
James
Mark Hadfield
> That's great! Now how about if you explain it a little more
> didactically so the rest of us can get it?
Don't get him started--we'll never be able to get him to stop :-)
Seriously, James has had a damn good try at explaining these issues on
his blog, in a form that even I might hope to understand
http://julesandjames.blogspot.com/2006/07/more-on-detection-attribution-and.html
http://julesandjames.blogspot.com/2006/07/more-on-detection-attribution-and_15.html
http://julesandjames.blogspot.com/2006/07/more-on-detection-attribution-and_16.html
--
Mark Hadfield "Kei puwaha te tai nei, Hoea tahi tatou"
m.had...@niwa.co.nz
National Institute for Water and Atmospheric Research (NIWA)
Michael Tobis
Hmm, this explains a lot.
I learned a good deal of statistics as an EE, trying to follow in the
footsteps of Norbert Weiner. In practice, most EE applications start
with the model that a signal exists, and that it has one of two (or N,
typically 2**N) values. So the decision isn't "how likely is this
observation given the existence of the signal" , but "which of these
signals is more likely given the observation"?
"Frequentism" doesn't really enter into it in stochastic systems engineering.
Deciding whether the climate as any sensitivity to CO2 at all always
struck me as pretty much meaningless. We know that greenhouse gases
are important. Why shouldn't *extra* greenhouse gases be important? So
I was always baffled by the emnphasis on the "detection" question.
Clearly for me the policy-relevant questions were always continuous,
not boolean. There really is no sensible null hypothesis without
throwing away a lot of extant knowledge.
"Do you believe in global warming" is and has always been a question
of very low utility. Attempting to answer validates the ill-posed
question.
On the other hand, I think that calling it a "Bayesian/frequentist"
distinction makes it all seem too subtle and even pretentious in a
public discussion. The jargon threw me off, and I actually think this
way! It is important to try to make these issues accessible.
Many people with little statistical background can understand the
concept of the right question vs the wrong question.
The attribution question as usually phrased is "assuming there were a
bunch of trials with no forcing, would less than 5% of them show as
much signal as we have now?", with the "signal" in turn often boiled
down to global mean surface temperature (throwing away lots of
information. Despite Roger's incorrect analysis, the answer to this
question is somewhere about halfway between 95% and 99.999999999% by
now, but it's the wrong question!
A better question, if we must identify the problem as "global
warming", is, given the evidence of a warming signal, what is the most
likely proportion of it that is due to anthropogenic forcing of the
atmosphere, as opposed to 1) free modes 2) natural forcing and 3)
measurement error? Denialists should note that nothing a priori
constrains this proportion to be less than 100%; there may be natural
cooling or a cooling bias in the measurements.
There are other useful questions besides that one, but it's a start;
it seems like a much sounder question to pose in consideration of the
observational record.
mt
Robert A. Rohde
There is a difference between being sensibly skeptical about new
research and unexpected claims and stubbornly disputing
well-established research and broady accepted claims. There are
situations where the second kind of skepticism can be useful to science
too (e.g. Einstein, Pasteur), but more often than not such attitudes
are unproductive for the researcher who holds them.
The individual who I am talking about basically believes a) that
climate modelling is too simplified and tuned to be useful, b) that
most of what gets published in the climate literature is dodgy and
shouldn't stand up to scrutiny, and c) the climate is basically too
complicated for us to predict.
Obviously if one is going to take those positions, it is not hard to
see that such a person might say that anthropogenic global warming
hasn't been established and even if it does exist we don't know what it
means for the future.
Incidentally, I agree with him that there is a lot of garbage in the
climate science literature, but that doesn't stop climate models from
being useful, or negate basic points like increasing greenhouse gases
can be expected to lead to more warming.
Michael Tobis
The weaker climate science is, the less we can constrain the impact of
anthropogenic actions; therefore we should be all the more vigilant
about minimizing observable changes in the radiative properties of the
atmosphere.
Presuming our knwoledge is of little value, we cannot then exclude
outcomes of trivial consequence, but we also cannot exclude outcomes
of enormous consequence.
So a rational risk-weighting values the risk as more severe the less
one esteems the knowledge of the climatological field. I always find
the arguments of those who claim that climatologists know nothing, and
that therefore we should do nothing, stunningly illogical. For all
that, this line of "argument" is extremely common.
mt
Jim Torson
> > Robert A. Rohde wrote:
> > >
> > > Sorry, no. He's a closet skeptic that I've closely interacted with in
> > > the past, but not someone that is publicly known for a skeptical view.
> > > Out of respect for his privacy, I am not going to identify him here.
>The individual who I am talking about basically believes a) that
>climate modelling is too simplified and tuned to be useful, b) that
>most of what gets published in the climate literature is dodgy and
>shouldn't stand up to scrutiny, and c) the climate is basically too
>complicated for us to predict.
>
>Obviously if one is going to take those positions, it is not hard to
>see that such a person might say that anthropogenic global warming
>hasn't been established and even if it does exist we don't know what it
>means for the future.
Hmmm... Does this mean that the skeptics are right when they
claim there are a lot of climate scientists who doubt AGW but
who are afraid to speak up about it?
How widespread is this view? What are they afraid of?
Should we begin to doubt the claims of scientific consensus?
Jim
Mark Hadfield
> The individual who I am talking about basically believes a) that
> climate modelling is too simplified and tuned to be useful, b) that
> most of what gets published in the climate literature is dodgy and
> shouldn't stand up to scrutiny, and c) the climate is basically too
> complicated for us to predict.
Until this guy is willing to state these views *and justify them* in
public, there's not much the rest us can do about them, is there?
James Annan
> Hmmm... Does this mean that the skeptics are right when they
> claim there are a lot of climate scientists who doubt AGW but
> who are afraid to speak up about it?
>
> How widespread is this view? What are they afraid of?
> Should we begin to doubt the claims of scientific consensus?
I doubt that there are many who doubt the broad consensus as expressed
by points 1-3 in RC:
<http://www.realclimate.org/index.php/archives/2004/12/just-what-is-this-consensus-anyway/>
although the "indeed accelerate" in pt 3 is very much predicated on
expectations of what is going to happen in the future wrt emissions.
With slightly more precision, I would say that there is broad consensus
that the GCMs will give fairly good predictions of future temperature
trends on the broadest scales when given realistic forcing on the
multidecadal time scale. Which means, more GHGs means more warmth almost
everywhere, especially northern latitudes and over land.
That still leaves lots of room for disagreement over the edges of
"consensus" and what we can say with credibility about future climate
changes (and their consequences) in detail.
I would agree that there is probably is a bit of pressure on people to
not say things that are too easily taken as critical of alarming
results. Eg, there were apparently some people who were not prepared to
go on the record for the BBC's "Overselling climate change" program. But
perhaps this is more of an interpersonal thing (not wishing to
criticise a colleague) than any widespread silencing of the sceptics in
particular.
James
Raymond Arritt
> Hmmm... Does this mean that the skeptics are right when they
> claim there are a lot of climate scientists who doubt AGW but
> who are afraid to speak up about it?
>
> How widespread is this view? What are they afraid of?
> Should we begin to doubt the claims of scientific consensus?
I don't think there is more than a small minority who "doubt AGW" as
such. If there were, those of us who attend conferences would have at
least heard talk over coffee breaks and the like.
There is a larger body who are skeptical of some of the more extreme
contentions regarding the consequences of AGW or who have doubts on
specific aspects of model projections. (I'd include myself in this group.)
The idea of scientists being "afraid to speak up" perhaps applies to
some in private industry or government who have to stay in the good
graces of their superiors. It certainly doesn't apply in academia; if
anything very much the opposite.
Tom Adams
Robert A. Rohde wrote:
> Eric Swanson wrote:
> > Robert A. Rohde wrote:
> > > Eric Swanson wrote:
> > > > As a matter of curiosity, would you identify the "paleoclimate
> > > > researcher" you mentioned in your post??
> > >
> > > Sorry, no. He's a closet skeptic that I've closely interacted with in
> > > the past, but not someone that is publicly known for a skeptical view.
> > > Out of respect for his privacy, I am not going to identify him here.
> >
> > Sorry, but most scientists are skeptics by nature. A good scientist
> > must ALWAYS be ready to question the accepted explanations, else how
> > could he/she ever come up with new and different ideas and theories?
> > Since you won't give a name, would you give a summary of his
> > reasoning?
>
> There is a difference between being sensibly skeptical about new
> research and unexpected claims and stubbornly disputing
> well-established research and broady accepted claims. There are
> situations where the second kind of skepticism can be useful to science
> too (e.g. Einstein, Pasteur), but more often than not such attitudes
> are unproductive for the researcher who holds them.
>
Actually the lines of inquiry implied by your skeptic should be quite
productive:
> The individual who I am talking about basically believes a) that
> climate modelling is too simplified and tuned to be useful,
You should be able to get a major publication out of that one,
by studying the characteristics of the models.
> b) that
> most of what gets published in the climate literature is dodgy and
> shouldn't stand up to scrutiny,
Well then, scutinize them.
> and c) the climate is basically too
> complicated for us to predict.
Discover the real factor(s) that are making the measurements appear to
track the model predictions.
>
Of course, armchair skepticism is unproductive regardless of its
content, if you are not even willing to even reach out of your armchair
and touch a keyboard (which is all it takes to study the models after
all.)
Alastair McDonald
----- Original Message -----
From: "Tom Adams" <tada...@yahoo.com>
To: "globalchange" <global...@googlegroups.com>
Sent: Thursday, July 27, 2006 6:20 PM
Subject: [Global Change: 417] Re: Op-ed on policy and probability
>
> Robert A. Rohde wrote:
>> The individual who I am talking about basically believes a) that
>> climate modelling is too simplified and tuned to be useful,
>
> You should be able to get a major publication out of that one,
> by studying the characteristics of the models.
But the climate modelers assigned to peer review it would reject such a
paper out of hand!
>> b) that
>> most of what gets published in the climate literature is dodgy and
>> shouldn't stand up to scrutiny,
>
> Well then, scutinize them.
Well, take the MSU and radiosonde measurements. They "proved" that
the MSU measurements had a slight flaw, and now they are saying that
the radiosondes must be wrong because they do not fit their new values
they have invented for the MSUs to fit their models.
>> and c) the climate is basically too
>> complicated for us to predict.
>
> Discover the real factor(s) that are making the measurements appear to
> track the model predictions.
The measurements do not track the model predictions (see above), but the
modelers claim they do. For instance in the Hadley model the ISR and
OSR at the TOA do not balance when running the system in equilibrium!
Moreover, the models do not give the correct height for the cloud base, but
the weather men know how much to correct for that error. Then the climate
modelers say their models must be right because they are the same as the
ones used by meteorologists, and they work. They don't! The correct
forecasts are produced because the weather men know where to tweak the
computer output.
Meanwhile the climatologist have been trying to tweak the cloud schemes
to make them work, but they cant because the basic radiation model is
wrong.
> Of course, armchair skepticism is unproductive regardless of its
> content, if you are not even willing to even reach out of your armchair
> and touch a keyboard (which is all it takes to study the models after
> all.)
No one will listen to sense, they are too skeptical!
Cheers, Alastair.