From: bobg@Radix.Net (Robert Grumbine)
Newsgroups: sci.environment
Subject: Re: Warmest Spring on Record
Date: 10 Jul 2000 11:50:22 -0400

In article <1FI95.2789$_J1.12259@newscontent-01.sprint.ca>,
Ian St. John <istjohn@spamcop.net> wrote:
>
>I wish that you would clarify one point for me? Why would *ground level*
>smog ( from coal plants) reduce air temperature? I can see stratospheric
>particulates doing so by blocking sunlight, but ground level smog would just
>transfer the heat from the smog particle instead of ground soil particles.
>Additionally, the small particle size and distribution ought to make energy
>capture more efficient ( lower albedo) and dust on normally high albedo
>areas, such as snow cover, ought to exacerbate the problem, not solve it.

  It looks like the matter of how the aerosols work has been mentioned,
but not the initial problem: how to get from ground to stratosphere.
The coal burning is done near the surface, and the exhaust plume doesn't
extend more than a km or two up from surface.  So getting the exhaust
from 1 km to 12 km is a challenge.  The way it works is that the exhaust
is sulfur-bearing _gas_.  The gas can diffust through the atmosphere ok.
In time, it is possible for the sulfur-bearing gas molecules to combine
with enough others to create solid particulates.  The particulates then
behave as described.

--
Robert Grumbine http://www.radix.net/~bobg/ Science faqs and amateur activities notes and links.
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