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Re: population growth & physics ed



OK, I'll bite. How can burning fossil fuels *reduce* the amount of C14
in the atmosphere? I can see where it would reduce the proportion of
C14, since the carbon released will have most of its C14 decayed, but
how is the actual amount reduced?

By the way, C14 isn't the only radiation released into the atmosphere
by burning fossil fuels. If you ever toured a coal power plant, you
have seen radiation danger signs all over the place. This is because
the trace amounts of radioactive elements present in coal go right into
the environment when the coal is pulverized and burned. Coal power plants
emit significantly more radiation into the atmosphere than do nuclear
power plants.

Well done; you've got half of it. Permit me merely to paste part of a note
to another correspondent to answer your question. I don't want to post it
quite yet.

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