Re: [Phys-l] global temperatures

["Richard Tarara" <rbtarara@sprynet.com>]

----- Original Message ----- 
From: "kyle forinash" <kforinas@ius.edu>
> Some factoids (mostly from the IPCC). Although the total annual average
> insolation remains constant for the earth over hundreds of thousands of
> years (even including orbit changes- and changes in sun intensity occur
> much slower), the LOCAL change at 60deg latitude is a seasonal variation
> of around ~400W/m^2. It is this LOCAL variance which is thought to give
> rise to changes from ice age to interglacial (carbon dioxide appears to
> act as a feedback mechanism for this change, rising in warm climates and
> falling in cool climates).
Not sure that 'feedback' is the right term here.  The rise and fall of CO-2
shows considerable lag behind the rise and fall in global temperatures.  Mr.
Gore makes this a central focus in his presentation but then somehow
(strongly) suggests that this somehow proves that CO-2 drives temperature
change.  [Not arguing that it can't, or isn't, just that the historical data
does not show this.]  Anyway, it seems possible that warmer temperatures
produce more plant life which will show up down the line as more decaying
biological material (both in Fall/Winter and longer term as forest/jungle
bedding).  The CO-2 rises as the amounts of materials rise significantly
(takes a while)--then when it gets colder it again takes time to exhaust the
excess decaying vegetation left over from the warm period, but eventually
the CO-2 drops again.  It is what is clearly seen in the historical graphs.

A question I have with the now common 'it is consistent with the climate
models' when someone _legitimately_ asks about Antarctica or the 10 year
plateau in global temperature rise, is whether the phenomena are consistent
with the models or the models consistent with the phenomena.  In other
words--are the models constantly being tweaked with the new data to stay
'consistent' or is the consistency _really_ based on some basic
physics/chemistry.   Did any of the models run 10 years ago predict the
plateau or the behavior of Antarctica?    I would though, like these issues
addressed scientifically and not with scorn and ridicule for those asking.

Another year of my energy class and project to rid the U.S. of Oil and
Natural Gas usage within a century--this year a $50 trillion dollar price
tag (doesn't seem so terribly much anymore since the age of bailouts) and
450,000 square miles of land use, and once again, real difficulties in
quantifying a 25% reduction in energy use through efficiency and
conservation.  I try to push that we need to move in this direction (clean
coal if possible, nuclear for another century, lots of wind, lots of solar,
storage techniques for the wind and solar to ensure 'energy on demand'
perhaps with hydrogen, some biomass (that takes the land) needed to fuel
some vehicles, and hold out a little (but not a lot) of hope for something
exotic (space based solar or fusion).  We need to do it regardless of global
warming concerns, but we need to do it sooner because of such--if for no
better reason,  just to be on the safe side.

Rick

Richard W. Tarara
Professor of Physics
Department of Chemistry & Physics
Saint Mary's College
Notre Dame, IN 46556