"Don Foreman" wrote in message
...
On Sun, 25 Jul 2010 16:34:53 -0400, "Ed Huntress"
wrote:


"Don Foreman" wrote in message
. ..
On Sun, 25 Jul 2010 10:47:40 -0400, "Ed Huntress"
wrote:


wrote in message
...
On Jul 25, 2:47 am, "Ed Huntress" wrote:

This is different carbon?

Yeah, this is VERY different carbon. When you sequester vast amounts
of
it
underground, for millions of years, and then release large quantities
of
that carbon over a couple of hundred years, you wind up increasing the
CO2
content of the atmosphere.

When you sequester carbon via photosynthesis (the source of all of our
food), and re-release it in a cycle of a few years, at most -- unless
you
eat trees -- you don't have any significant effect. The effect is
steady-state, in which you have small amounts of carbon tied up over a
short
period of time and then re-release it.

You have an engineering background, Don. Don't play dumb. d8-)

--
Ed Huntress

If I capture a sample of CO2 and send it to you, neither you nor any
chemist you can hire will be able to determine if it was ever
sequestered, much less where and when.


That's irrelevant, and you know it. What matters is where it has been, and
for how long.

No. What matters is how much is being released to atmosphere by all
mechanisms vs how much is being removed from atmosphere by all
mechanisms.

Don, that wasn't the question I addressed. Once again, there are two
questions: whether human respiration adds CO2 to the atmosphere (no), and
whether burning fossil fuels adds CO2 to the atmosphere (yes).

Are we agreed on this?

The only time constant here is the rate of concentration
change, which is proportional to the net increase of atmospheric CO2
per unit time divided by the total atmospheric volume.

No, that wasn't the question. That's a larger question, but my responses are
true, regardless of what you may want to speculate about what happens to
that CO2 after it's in the atmosphere.


CO2 from animal respiration doesn't magically migrate to trees while
CO2 from fossil fuel combustion goes directly to greenhouse. It may
be politically expedient to represent things that way, but that isn't
what happens.

It doesn't matter which CO2 goes where. The question is whether the CO2
emitted by humans comes from a short-term sequestration -- whether that CO2
we exhale was in the atmosphere a few minutes, months, or possibly a few
years ago, and we've just put it back where it was -- and whether the CO2
emitted by burning fossil fuels comes from sequestration effected millions
of years ago. The answer to both is yes.

No matter how much you complicate it, those two things are facts. And that
was the issue. The net effect of one is to neither add nor subtract from
atmospheric CO2. The net effect of the other is to add to atmospheric CO2.

Now, what happens in terms of production of carbonates and dissolved
carbonic acid? I don't know. You don't know. Experts seem to be arguing
about that as we speak. And it doesn't matter. Because, before it has an
opportunity to re-combine with other chemicals and become temporarily
sequestered again, or sequestered for all time -- or not -- it has to get
into the ATMOSPHERE first. And that was the point.


I don't dispute that increasing the output by burning fossil fuels has
increased the load, but it's also true that reducing the amount
being removed by replacing vegetation with concrete decreases the rate
of removal -- again raising concentration.

That's another issue. Neither you nor I can put numbers on it, so all we can
do is name some effects, without qualifying whether they're significant or
just distractions. You CAN put some reasonable numbers on the amount of
fossil fuel we burn, and thus on the amount of CO2 that's added to the
current atmospheric volume of CO2.


In addition, increasing ocean temperatures can release huge amounts of
CO2 now held in solution.

That's a larger question. You're getting into complications of the system as
a whole, and not you, nor I, nor any of the self-styled climatologists on
this NG have a freaking clue about the actual volumes any such interactions
may incur. All you can do is confound the issue.

But, again, there's no confounding the original question, and the only claim
that I made.



It's more sensible to think of this as an accounting problem, and in
fact responsible scientists do look at it in that way by defining
carbon sources and carbon sinks.

Carbon sources emit carbon into the atmosphere. Those include animal
respiration, combustion, and various other sources.

Animal respiration does not ADD to the carbon in the atmosphere, in any
meaningful time frame.

Of course it does.

Nonsense. That carbon was trapped for a short time, in a closed loop that
starts with photosynthesis. Do you deny this?

Then other processes subract.

You have it backwards. First, there is short-term sequestration by
photosynthesis. Then we eat food thus produced, and re-release the carbon.

If it was as you describe, what would we be eating in the first place? Air?

Don, trying to equate the trapping and releasing of CO2 in the production of
food, and then eating it and exhaling CO2, with burning fossil fuels is
profoundly misleading about the net effects. Larry sounded like he was
equating the two. That's why I commented. I've pointedly avoided discussing
the system-wide effects of CO2 sequestration and release, and of its effects
on global warming, because they have nothing to do with the original point.

Let me reiterate that point so there is no confusion. Burning fossil fuel
releases carbon into the atmosphere that was sequestered for millions of
years. We do it relatively quickly, so the net effect is to increase the
levels of atmospheric CO2 to something higher, in the direction of the
levels that existed millions of years ago.

Eating and exhaling does not. Before you have something to eat, CO2 must be
sequestered from the atmosphere into plant life, at some recent time. And
it's a continuous process. There is some mean time of CO2 sequestration for
that plant life, and it's on the order of a few years. The CO2 that we
release from burning fossil fuels was sequestered for MILLIONS of years. The
net effect in each case is vastly different. In the case of eating plants or
animals that eat plants, we're participating in a cycle that requires,
first, that CO2 must be sequestered from the atmosphere within recent years.
Then we release it, and the cycle, measured in a few years, repeats. There
is no net increase in atmospheric CO2.

If the subtractive
processes can't keep up with the additive processes, then atmospheric
concentration increases.

Something else, much more consequential, happens first: We starve. g

Again, you have the process backwards. First, short-term sequestration. Then
we eat. Then there is more short-term sequestration -- or we don't eat
again.

But we do. And ALL of the carbon we emit comes from that short-term
sequestration, and that particular cycle keeps repeating. Even if we had no
relationship to other trapping and emitting of CO2, that closed cycle, which
is quantifiable to a reasonable degree, would continue. You can treat it in
isolation of other effects because you know quite accurately how much carbon
is involved, how it's trapped, and how it's emitted -- and trapped again,
and re-emitted, etc.

By ignoring those facts, all you do is obfuscate these simple,
well-documented, measurable facts.


All meaningful "emission" of carbon by animals was
aborbed originally from the atmosphere and stored for, typically, a year
to
a few years. All meaningful emission of carbon resulting from the burning
of
fossil fuels was absorbed from the atmosphere millions of years ago. So
burning fossil fuels increases current carbon levels.

Burning fossil fuels releases CO2. So does animal respiration, forest
fires, and warming oceans.

Burning wood does not,
as long as you replace those trees.

Of course it does. If trees are replaced, then they will serve as a
CO2 sink but not until they are replaced and grow to size.

And how many millions of years does that take? Do you recognize the
qualitative difference that results from the different time scales?


Carbon can also be
released from polar ice and ocean water with change in temperature.

Carbon sinks remove carbon from the atmosphere. Those include
solution in ocean water and captivation in ice, photosynthesis,
formation of carbonic acid by rain, formation of seashells and
eggshells that are primarily calcium carbonate, etc etc. Loss of
rainforest constitutes a major loss of carbon sink.

Very interesting, perfessor. But it has nothing to do with the question
raised, which I answered, and which you responded to: does human
respiration
increase carbon in the atmosphere? It does not, over a closed cycle that's
mostly a few years in length.

If production equals consumption, there is no cycle length at all.
Whenever production exceeds consumption, concentration will steadily
increase.

No, the cycles still exist. Mixing the CO2 together doesn't change that. All
it does is obscure the cycles that are at work.


Does burning fossil fuels do so? It does, over
a cyle that's millions of years in length. Thus, the latter can increase
CO2
levels to prehistoric levels. The former cannot.

The fact that fossil fuel is millions of years old is immaterial.

That's a foolish thing to say, Don. You're ignoring the relative time to
sequester a fossil fuel, versus a plant that's used for food. The carbon
cycle for food is 100% (or nearly so) contained within a matter of years.
The cycle for fossil fuel is millions of years in, and now hundreds of years
out. We're dumping large amounts of CO2 into the atmosphere that required
millions of years to sequester. When we eat, we're emitting at about the
same rate as the sequestration of CO2 in food.


The
issue is that burning it releases CO2 now, which is in addition to
other sources like animal respiration, which makes the net release
rate greater than the present removal rate -- which is undoubtedly
less than it was 200 years ago.

Duh...g



If the amount of CO2 being emitted exceeds the amount being removed,
then the CO2 concentration in the atmosphere increases. If the
concentration in the atmosphere is to be controlled, then it's
necessary to consider all sinks and all sources to find ways to get
and keep them in equilibrium.

Ok, you go first. g I'll help you on the points that were raised he
Emitting CO2 from fossil sources increases the amount of CO2 in the
atmosphere. Emitting CO2 from people does not.

The amount of CO2 in the atmosphere increases if the amount being
released exceeds the amount being removed. Even if we eliminated all
fossil fuel combustion, if we reduce the planet's ability to remove
CO2, as by replacing vegetation with concrete, then the CO2 emitted
from people would increase the amount in the atmosphere.

No, it wouldn't. It CAN'T. All of the CO2 emitted by people HAS TO be
sequestered first in plants, through photosynthesis, over the short term.


We need to look at the whole issue, not just one aspect of it.

Not if the question is about the emission of CO2 by people, versus engines
burning fossil fuels. That's ALL I've commented upon. And your statement
above, about increased CO2 emitted by people if we pave over the land with
concrete, is the fundamental flaw in your logic. It is impossible -- at
least, until we're able to synthesize food from something other than plant
sources. Maybe we can eat carbonate rocks. g

ALL of the CO2 we emit must first be sequestered in plants, via
photosynthesis. It's a short, closed cycle. If we pave over the land, we
have nothing to eat. The only "emitting" we'll do then will occur as our
bodies decompose. But even that CO2 "emission" is the result of plant life
stored in our bodies over a matter of decades. It has no net effect on
atmospheric CO2.



This bookkeeping isn't difficult to understand, but politicans and
zeolots often seem to find the notion of "balance" incomprehensible.

Not to mention the doctors of climatology who discuss the subject on this
newsgroup. g

--
Ed Huntress