Don Foreman on Sun, 25 Jul 2010
22:32:11 -0500 typed in rec.crafts.metalworking the following:
On Sun, 25 Jul 2010 22:14:45 -0400, "Ed Huntress"
wrote:


"Martin H. Eastburn" wrote in message
...
CO2 is CO2 no matter where it comes from.

From bugs man, forest fire, Oil Field on fire or decaying matter.

Martin

If it comes from recent photosynthesis, it adds nothing to the atmosphere.
If it comes from fossil fuels, it restores CO2 to the atmosphere that hasn't
been there for millions of years. It increases CO2 levels as a result.

I think you mean "if it comes from oxidation of organic matter that
was produced by photosynthesis..." Photosynthesis doesn't release
CO2, it consumes it.

Any release of CO2 from any source adds immediately to the local
atmosphere. If that were not true then submarines wouldn't need CO2
scrubbers to deal with CO2 from respiration: just add oxygen to
replace that used.

Simultaneously, current photosynthesis and other processes subtract
immediately from atmosphere in their locale. Any concentration
gradients that result are soon resolved by mixing due to winds and
Dalton's law of partial pressures. If these two processes balance
over a given period of time then there is no net change during that
period. If the CO2 added by burning fossil fuel is not balanced by
a corresponding increase in subtraction by photosynthesis or other
subtractive mechanism, then atmospheric concentration will increase
over time. In fact, over the past 200 years or so we have both
increased the rate of addition and reduced the rate of subtraction by
destruction of vegetation.

To mitigate this, we must look at both reducing production rate and
increasing subtraction rate. Breathing less is not a viable option
(pun intended) but fossil fuels are by no means the only other source
and subtraction is just as important in balancing the CO2 budget.

Plant trees. Or other woody plants which grow rapidly. Then take
those plants and "sequester" the carbon (aka "bury it").
One proposal is to add trace amounts of Iron to various parts of
the ocean. The trace amounts of iron will increase the amount of
phytoplankton (iirc) which in turns sucks up a lot of carbon dioxide,
and precipitates out to the bottom of the ocean.

For a high tech solution - "shades" - big mylar sun shades in orbit.
That actually won't do much for CO2, but it will cool the earth,
offsetting the increase in Greenhouse Gasses.
--
pyotr filipivich
We will drink no whiskey before its nine.
It's eight fifty eight. Close enough!