Evidently global warming started about 8,000 years ago, long before the

Industrial Revolution. An article explaining this is on page 46 of the
Scientific American magazine, March 2005, by William F. Ruddiman. It
turns out that human agriculture (planting seeds, domesticating
animals, etc.) really took off about the same time that global warming
started. (Archeological evidence of farming goes back to 11,000 BC, in
the Tigris and Euphrates deltas, but large scale agriculture didn't get

going in the Nile, Yangtze, Ganges, and other big deltas around the
world until a thousand years later. Some important dates in human
development can be seen by clicking on the following link:
http://historylist.blogspot.com ). Worldwide agriculture led to
cutting
down the forest trees that ordinarily consume carbon dioxide. This is
just as important as generation of the gas by automobiles, etc., when
it comes to global warming.

Large farm animals such as cows exhale carbon dioxide, but a worse
effect is the fact that their intestines exude huge amounts of methane
gas. Methane gas is a much more powerful global warming agent than
carbon dioxide, although there is less of it in the atmosphere.

This is a "vicious circle" sort of thing, where "the more it happens,
the
more it happens further." It involves "positive feedback,"
overwhelming the earth's natural temperature cycles. It would take
drastic measures to slow this down. But evidently people have started
this cycle, and we could probably diminish it also, if the population
could be very much decreased.

By the way, looking at the repeating cycles of atmospheric temperatures

in the geological record, we are overdue for another ice age.
(You can see what I published on that subject, by clicking on this
link:
http://www.sciencenews.org/pages/sn_...97/letters.htm .)
The Ruddiman article in Scientific American claims that human-induced
global warming has prevented the next ice age.

The only way we could stop the global warming and keep things stable
would be to decrease the world's population of human beings, in a
carefully controlled manner. That would affect both industry and
agriculture. (Cutting back on industry alone won't do the trick.) It's
actually possible to slowly reduce the number of people, because the
non-immigrant populations of the U.S. and Europe have been falling
spontaneously, even without the "famous 3" means of "famine, war, or
plague." (In fact the fast falling population of educated workers is a
big
problem for the support of pensions such as Social Security, and for
generally continuing our economic growth.)

If we don't voluntarily do something about the world's excessive
population, we're liable to get the first of the "famous 3 ---
famine,"
because of warming-induced drought. That could easily lead the other
ones, like "war." In fact, this seems pretty likely, if the ocean rises

and we all get crowded into smaller spaces.

These points (especially POPULATION-provoked temperature change,
in addition to industrial effects") should be intensely discussed in
high
school science and "social studies" courses, as well as in national
governments. Whether or not we can get poor countries to hold back
population growth is unknown, but we ought to be trying harder.

Dan.
http://homepage.mac.com/shanefield/Resume1.html

Felly sgrifennodd :
The only way we could stop the global warming and keep things stable
would be to decrease the world's population of human beings, in a
carefully controlled manner. That would affect both industry and
agriculture.

I agree completely! The only trouble is, any politician who says this is
accused of being an extremist.

It's not just for GW reasons though; it's also for the balance of nature,
protection of the environment, human quality of life, etc., etc.

Adrian
--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.
http://users.aber.ac.uk/ais uk

It's not just for GW reasons though; it's also for the balance of nature,
protection of the environment, human quality of life, etc., etc.

Adrian

Yes, I'm afraid as oil production declines over the next 50 years the
population level will have to come down to a sustainable two billion or so.

Incidentally seems a lot of very high cloud this year - not much in the way
of true blue skies. Any thoughts on this? Its bad for Astronomy!

John

None of this explains why CO2 levels are rising rapidly at the
present time. Billions of farting cows? Come off it. Has it occurred
to the author that agriculture may have started as a result of global
warming rather than being the cause of it? I'm a bit surprised at
Scientific American publishing this sort of stuff.

Tudor Hughes, Warlingham, Surrey.

Yeah, I know, there's conflicting evidence about all this stuff. *I'm
just going by what that Ruddiman guy sez (you could get some idea at
http://www.sciam.com and searching his name). *He wrote some books
about it, published by Princeton and Chicago Universities. * And he is
a Prof. Emeritus of Envir. Sci. at U. of Virginia. *So he ought to know

something. *(And he has some nice looking female grad students ----
better looking than most ! *See
http://www.evsc.virginia.edu/f aculty/graduates.shtml *.)

But a bunch of quite smart people in Australia and Canada have claimed
this global warming (and "Hockey Stick") stuff in the U.S. science
establishment is all just biased selection of data, (maybe
subconciously) designed to get funding for next years grad students.
(Hey, no crisis, no funding!) *See for example, all the data and nice
graphs at http://www.john-daly.com/hocke y/hockey.htm .

Reminds me of contentions that vitamin E tends to prevent cancer. *But
I take it anyhow --- best evidence is that might prevent prostate
cancer, and I'm an old man. *All we can do is go by the best evidence
available, it seems to me.

"Adrian D. Shaw" wrote in message
...
Felly sgrifennodd :
The only way we could stop the global warming and keep things stable
would be to decrease the world's population of human beings, in a
carefully controlled manner. That would affect both industry and
agriculture.

I agree completely! The only trouble is, any politician who says this is
accused of being an extremist.

It's not just for GW reasons though; it's also for the balance of nature,
protection of the environment, human quality of life, etc., etc

Thank God for plastic buckets

In article , writes:


...Worldwide agriculture led to cutting
down the forest trees that ordinarily consume carbon dioxide. This is
just as important as generation of the gas by automobiles, etc., when
it comes to global warming.


Some *minor* quibbles coming up:


Is it "just as important"? I don't think so, and I don't think the
figures would support it.

The loss of the temperate forests occurred sufficiently long ago that
the resulting CO2 budget delta has been played out. Our projected
consumption of fossil fuels will exceed that effect by quite a
considerable margin...

The loss of forests and jungles exacerbates the situation, but they are
not an equal main factor to the burning of fossil fuels.




Large farm animals such as cows exhale carbon dioxide, but a worse
effect is the fact that their intestines exude huge amounts of methane
gas. Methane gas is a much more powerful global warming agent than
carbon dioxide, although there is less of it in the atmosphere.

You have the emphasis wrong: there is so much more CO2 than CH4 in the
atmosphere that it dominates the greenhouse effect. CO2 also absorbs at
a wavelength where H20 is transparent, thus "blocking the vent".


By the way, looking at the repeating cycles of atmospheric temperatures
in the geological record, we are overdue for another ice age.


I'm overdue a pay rise, but I won't get one:-)


The only way we could stop the global warming and keep things stable
would be to decrease the world's population of human beings, in a
carefully controlled manner.

One way, and a laudable aim in my opinion, but not the only way.

If we don't voluntarily do something about the world's excessive
population, we're liable to get the first of the "famous 3 --- famine,"
because of warming-induced drought.

Our future may turn out to be a simple race to oblivion between what you
describe - global warming induced famine - and viral pandemics, both caused
by the consequences of excessive human populations:-(


These points (especially POPULATION-provoked temperature change,
in addition to industrial effects") should be intensely discussed in
high school science and "social studies" courses, as well as in national
governments. Whether or not we can get poor countries to hold back
population growth is unknown, but we ought to be trying harder.

That is a huge question. Religion, culture, power, education and
standards of living play overwhelming roles. But ranged against those
obstacles are the relentlessly increasing disasters which will force
everyone to take notice eventually, even Lawrence should he survive
long enough:-)


Cheers,

keith




---
Iraq: 6.5 thousand million pounds, 80 UK lives, and counting...
100,000+ civilian casualties, largely of coalition bombing...

Hey, all bets are off! Here's the latest and greatest. I just found
that an article in Nature that sez (if it's correct) that the present
warm period between ice ages will last 28,000 yrs, not just about
12,000. So we don't need Ruddiman's explanation for the lack of an ice
age yet (due to agriculture). Just click on
http://www.nature.com/cgi-taf/DynaPa...e02599_fs.html
Now another problem comes up: is the same phenom. (a pile-up of sev'l.
natural cycles) going to cause a huge warming trend, even worse than
man-made trends? There have been purely natural cycles in the distant
past (before people) when the CO2 was about 5 times the present value,
and the temp. super-high. Is this another one?

By the way, the next (current) issue of Sci. Amer. Mag. had a letter by
Ruddiman defending his claim. He should have referred to this thing in
Nature, but he didn't. Makes me wonder about all these guys' claims.

DanS.

"Keith Dancey" wrote in message
...
In article ,
writes:


...Worldwide agriculture led to cutting
down the forest trees that ordinarily consume carbon dioxide. This is
just as important as generation of the gas by automobiles, etc., when
it comes to global warming.


Some *minor* quibbles coming up:


Is it "just as important"? I don't think so, and I don't think the
figures would support it.

The loss of the temperate forests occurred sufficiently long ago that
the resulting CO2 budget delta has been played out. Our projected
consumption of fossil fuels will exceed that effect by quite a
considerable margin...

The loss of forests and jungles exacerbates the situation, but they are
not an equal main factor to the burning of fossil fuels.




Large farm animals such as cows exhale carbon dioxide, but a worse
effect is the fact that their intestines exude huge amounts of methane
gas. Methane gas is a much more powerful global warming agent than
carbon dioxide, although there is less of it in the atmosphere.

You have the emphasis wrong: there is so much more CO2 than CH4 in the
atmosphere that it dominates the greenhouse effect. CO2 also absorbs at
a wavelength where H20 is transparent, thus "blocking the vent".


By the way, looking at the repeating cycles of atmospheric temperatures
in the geological record, we are overdue for another ice age.


I'm overdue a pay rise, but I won't get one:-)


The only way we could stop the global warming and keep things stable
would be to decrease the world's population of human beings, in a
carefully controlled manner.

One way, and a laudable aim in my opinion, but not the only way.

If we don't voluntarily do something about the world's excessive
population, we're liable to get the first of the "famous 3 --- famine,"
because of warming-induced drought.

Our future may turn out to be a simple race to oblivion between what you
describe - global warming induced famine - and viral pandemics, both
caused
by the consequences of excessive human populations:-(


These points (especially POPULATION-provoked temperature change,
in addition to industrial effects") should be intensely discussed in
high school science and "social studies" courses, as well as in national
governments. Whether or not we can get poor countries to hold back
population growth is unknown, but we ought to be trying harder.

That is a huge question. Religion, culture, power, education and
standards of living play overwhelming roles. But ranged against those
obstacles are the relentlessly increasing disasters which will force
everyone to take notice eventually, even Lawrence should he survive
long enough:-)


Cheers,

keith




---
Iraq: 6.5 thousand million pounds, 80 UK lives, and counting...
100,000+ civilian casualties, largely of coalition bombing...



Thanks for the mention Keith :-)

In article , writes:

Now another problem comes up: is the same phenom. (a pile-up of sev'l.
natural cycles) going to cause a huge warming trend, even worse than
man-made trends? There have been purely natural cycles in the distant
past (before people) when the CO2 was about 5 times the present value,
and the temp. super-high.

Is *this* another one?

No, I don't think so.

Our empirical knowledge about orbits, solar flux, plate tectonics and
atmospheric chemistry is so much greater than even a few decades ago
that we now know what is changing, and by how much, to a high degree of
accuracy.

The natural cycles will continue, of course, at their own pace, but none
of those are changing as fast as the current temperature record. Only
anthropogenic greenhouse gas emmissions and atmospheric aerosols have
changed by amounts which go anywhere near explaining this temperature record.


The uncertainty which is left is all about fine-tuning the degree each
of these factors (greenhouse gases and aerosols) play in determining
surface temperatures, and the large degree of uncertainty about what that
(increased surface temperatures) will do to the various elements that make
up our environment... (how fast will the ice sheets melt?, how will corals
and the rest of the marine life react to warming?, how will ocean currents
react?, how fast will sea levels rise and by how much?, how will vegetation
react?, what will happen to precipitation? what will happen to wildlife?
what will happen to the tundra? soil erosion? floods? violent storms?
jet streams? climate patterns? etc etc)


Cheers,

keith





---
Iraq: 6.5 thousand million pounds, 80 UK lives, and counting...
100,000+ civilian casualties, largely of coalition bombing...