Re: population growth & physics ed

["Rick & Bea Tarara" <rbtarara@sprynet.com>]

Ok--so I'm a few thousand half-lives too late to get any C-14 from the
fossil fuels.  I stand corrected.  HOWEVER, I'm not sure I agree with
the rest.  

Let's assume that the production of atmospheric C-14 has remained
constant for the past several hundred years.  [Increases in methane and
whether or not more wood is burned today--worldwide--than in the past
may actually push the amount up.]  Now 200 years ago the oceans
absorbed a certain PERCENTAGE of the CO2 and let's assume a _rough_
equilibrium.  Now comes the Industrial Revolution and our use of fossil
fuels.  Today the AMOUNT of atmospheric CO2 has more than doubled and
continues to rise.  Because the new CO2 doesn't have any C14 the
CONCENTRATION of C14 has halved.  The oceans DO now absorb more CO2 on
an absolute basis, BUT what about a percentage basis?  Hard for me to
see how the percentage would be greater.  If anything, the percentage
absorption of atmospheric CO2 by the oceans should be down a
little--the overall amount of CO2 IS rising.  If the percentage
absorbed is lower than the percentage absorption of the C14 is lower
and there would be _slightly_ more atmospheric C14 due to the use of
fossil fuels.  At least this is my reasoning--????

My main point without the 'absurd' mistake {Leigh's language has been a
bit demeaning} was that burning fossil fuels IS NOT good for the
environment regardless of the level of the greenhouse threat, so it is
only prudent to actively pursue ways to reduce such use.

There have also been other posts--by others then Leigh--that seem to me
to border on "physicist arrogance" in dismissing the work of
climatologists, meteorologists, oceanographers, etc.  From the _little_
I actually know about the whole area of 'greenhouse research' what
stands out in my mind is how complex and interdependent the whole
system is.  While I agree with one of Leigh's earlier posts that
suggested the earth is much more resilient and self-correcting than the
'doom-sayers' suggest, it also seems obvious to me that we don't really
know what the limits of that resilience are.  While the oceans are part
of the self-cleansing
system, some models show critical boundary area events that can switch
the oceans from cooling to heating mechanisms.  Exactly where those
boundaries are (or if they're real) is very uncertain.  While it is
clear that we can 'artificially' heat the earth {which we might someday
WANT to do to prevent or moderate the next natural ice-age}, it is less
clear than we can cool it down if it gets too hot.  Under such
conditions it again is prudent to be careful.  We do have Venus as
proof that the global greenhouse effect CAN happen, and while I'm sure
we are in no danger of reaching Venus like temperatures, a rise of 3-5
degrees Celsius within a human lifetime would cause real problems on a
global scale--not doomsday problems, but serious ecological, economic,
and political problems.
----------
> From: Leigh Palmer <palmer@sfu.ca>

> Leigh
>
> > The C-14 puzzle is really twist. The original poster implied that
burning
> > fossil fuel would increase the amount of C-14 in the atmosphere;
that is
> > absurd, since fossil fuels contain no C-14 at all. C-14 is produced
in
> > the atmosphere by cosmic ray bombardment, and that which is
incorporated
> > into plants which become coal has all decayed by the time it is
burned.
> > That sets the stage. If one increases the amount of CO2 in the
atmosphere
> > with CO2 that has no C-14, the relative concentration of C-14 will
> > decrease, and more CO2 will dissolve in the oceans (plants are
relatively
> > unimportant), including more C-14. Thus the total C-14 in the
atmosphere
> > will be decreased by the burning of fossil fuels. I realize this
depends
> > on LeChatelier's principle, which many people pigeonhole as
chemistry,
> > but since I can derive it from elementary statistical mechanics I
consider
> > it to be physics.
> >
> > Incidentally, burning coal will indeed increase the *radioactivity*
in the
> > atmosphere, but it is really entirely free of C-14. The amount of
increase
> > for a coal-fired electric generating plant greatly exceeds the
tolerance
> > level for a nuclear plant of the same size.
> >
> > This is a crazy world.
> >
> > Leigh