From rmg3@access5.digex.net Tue Jul 15 08:32:04 EDT 1997
Article: 143158 of sci.environment
Path: news2.digex.net!digex.net!not-for-mail
From: rmg3@access5.digex.net (Robert Grumbine)
Newsgroups: sci.environment,sci.econ
Subject: Re: Global Warming May Not Be Taking Place
Date: 15 Jul 1997 08:29:17 -0400
Organization: Under construction
Lines: 74
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References: <33ADC577.682336E1@pipeline.com> <33AE94B0.7525A754@math.nwu.edu> <5q6u5g$frq@darkstar.ucsc.edu> <33CB456F.3E9693F5@pipeline.com>
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Xref: news2.digex.net sci.environment:143158 sci.econ:75224

In article <33CB456F.3E9693F5@pipeline.com>,
Steven Hales   wrote:
>David Michael Wright wrote:
>
>> In article <33AE94B0.7525A754@math.nwu.edu>,
>> Leonard Evens   wrote:
>> |Essentially all climatologists agree that without limits on
>> greenhouse
>> |gas emissions _in_the_future_, climate change is very likely.  That
>> is
>> |what the rest of the report is all about and it is what you
>> completely
>> |ignore in your posting.
>>
>> I am having a debate with someone on this. Is there an easy way to
>> prove this assertion, which begins with "essentially all
>> climatologists agree...". Do I have to buy or get the report?
>
>The problem with the climate debate today is that it has become
>politicized.  But one thing is certain:  The radiative formula based
>upon the Stefan-Boltzmann Law is unquestioned and is a point of
>universal agreement.  The Boltzmann Law simply states that for any
>increase in temperature average T of a spherical body, e.g., the earth,
>the amount of infrared radiation emitted by the body increases 16
>times.  

  No, it doesn't.  The law for blackbody radiation says that the
total energy emitted from a black body is proportional to the fourth
power of the (absolute) temperature.  The proportionality constant
is the Stefan-Boltzman constant.  A factor of 16 will only occur
for a doubling of absolute temperature.  Nobody is suggesting such
an event.

  Absolute temperature = 273.15 + Temperature in Celsius.  For the
earth's present planetary average, this is approximately 288 K.
(Absolute temperature is in Kelvins).  The present best estimates of
the amount of warming expected for doubling (*) of CO2 is to raise
that to 290.5.  

  *  Doubling of CO2 is an exceptionally low figure.  Best estimates
under business as usual scenarios are for a 6-fold increase in 
atmospheric CO2 levels.

>The greenhouse effect is caused by some of this long wave
>re-radiation being trapped by greenhouse gases or GHGs.  As the
>percentage of GHGs increases the more long wave radiation is trapped and
>since it is trapped in earth's troposhere the average temperature
>continues to increase as more and more long wave radiation is emitted
>from the surface and radiative balance is never achieved.  

  Not according to anybody who's read how radiative transfer really
works.  Balance is most definitely achieved.  It is just achieved
at a higher temperature.  A better picture is this: as you add more
GHG's to the atmosphere, it becomes more efficient at trapping 
radiation from the surface.  In order to emit enough radiation out
to space to achieve balance with what comes in from the sun, the surface
must emit more total radiation.  To emit more radiation, the surface
must be at a higher temperature.  This is _very_ basic, _very_
well understood physics.

[deletia]

>My feeling is that the debate is far from over and any consensus that
>has been supposedly been reached is a political consensus only as we
>"slouch toward Kyoto".

  Given the profound misunderstanding of basic physics you displayed
above?

-- 
Robert Grumbine rmg3@access.digex.net
Sagredo (Galileo Galilei) "You present these recondite matters with too much 
evidence and ease; this great facility makes them less appreciated than they 
would be had they been presented in a more abstruse manner." Two New Sciences