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[Phys-L] Re: [Political Action] The nature of the lack of proof (climatewarming) (Modified by Leigh Palmer)



This is curious. I don't participate for weeks, and then I create a
strange Gegenbeispiel to my own causality argument, according to the
time stamps Robert Cohen replied to my note before I posted it.

From: Robert Cohen <Robert.Cohen@PO-BOX.ESU.EDU>
Date: December 17, 2004 9:48:58 AM PST
Subject: Re: [Political Action] The nature of the lack of proof
(climatewarming)

On Friday, December 17, 2004 11:33 AM, Leigh Palmer wrote:

"The rapid rise in both surface temperature and CO2 is one of
the indications that humans are responsible for some of this
unusual warmth." [op. cit.]

logical fallacy: *post hoc ergo propter hoc*

If two events are consecutive they are causally related. In
this case I am not even aware that the indicated warming
occurs after the carbon dioxide increase. Unless that is
demonstrated the argument is equally strong (i.e. fallacious)
that warming causes the carbon dioxide increase.

[Is this from the same person who argued that forces
cause accelerations?]

Indeed. That is my understanding of causation. I believe I didn't argue
that point, however. It is an article of my faith that forces cause
accelerations. At some level we all rely upon belief.

Yes, *by itself* this quote exhibits false logic. However,
this quote simply neglects to mention the assumptions being
made in the argument, i.e. we know of a mechanism whereby
increased CO2 is associated with increased surface temperature
and we know that human actions are responsible for increased CO2.
We assume the reader accepts these assumptions.

Your argument is still fallacious. Just because we know one plausible
mechanism we shouldn't assume we understand the temperature response of
the complex system to a change in CO2 concentration. That is what the
modelers are telling us when they argue about the details.

"Other surface temperature data sets differ somewhat from
those shown here, but in all of them the modern temperatures
are generally greater than during the past several hundred
years." [op. cit.]

In all of them, eh? Satellite measurements of tropospheric
temperature are more extensive, less biased to northern
cities and, perhaps, deserve some attention. These "surface
temperatures", by the way, are really measurements of
atmospheric temperature taken at the Earth's surface.

Are you talking about
<http://www.ghcc.msfc.nasa.gov/MSU/images/tropo_temp.gif>?

Yes.

As you mention, the satellite measurements represent the
troposphere, not the surface. Just because we are unsure why
the troposphere shows no warming (perhaps even a slight
cooling) does not necessarily invalidate the measurements at
the surface. In addition, I believe these same satellite
measurements also indicate warming for the upper troposphere.

They do indeed, but they are the best data we have on a global basis.
Historical data for the last century are very weak over the oceans and
in the southern hemisphere. The cited piece suggests that *all* data
sets lead to this conclusion. This is not science, it is selling. That
is my point

"A climate model projection that includes both natural
processes and human activities closely matches actual
measurements of 20th-century temperature changes."

...

"The same climate model without human activity (natural
processes only) does not match the strong warming that
occurred during the past few decades." [op. cit.]

This example demonstrates clearly that models can be made to
fit data better if one has more free parameters to use.

My understanding is that the inversion process used to obtain
temperatures from satellite measurements is based upon the same
physics involved in the computer models. Computer models are not
based upon "fits". They are based upon physics. A significant
problem with the models is one of resolution. In order to model
the entire atmosphere, the grid points must be far apart, which
leads to a smoothing effect.

There are still lots of free parameters, and the results that are
published all rely to some extent on fits. The problem of climate is
far too difficult to solve from a first principles approach. That is
why there is more than one global circulation model.

Computing capability may reach high resolution in the foreseeable
future. Resolution is not the greatest problem faced by climate models.
Computing power alone will not solve the problems. There is much
physics yet to be learned.

I would not argue that global climate change is not occurring. Earth's
climate has seldom seen a period of stability as long as the one in
which we now live. Changeability has been the usual characteristic of
Earth's climate.

It is my contention that the case for an anthropogenic agent being
responsible for this change has not been made by science; it is in
essence a religious position. Furthermore I believe that this issue has
been embraced as a cause by many, including some scientists who should
know better.

Fortunately many competent scientists are still seeking answers to
climate problems. I expect to see the state of knowledge improve
significantly in the next decade.

Leigh