Posted on 03/06/2005 3:02:28 PM PST by blam
How prehistoric farmers saved us from new Ice Age
Robin McKie, science editor
Sunday March 6, 2005
The Observer
Ancient man saved the world from a new Ice Age. That is the startling conclusion of climate researchers who say man-made global warming is not a modern phenomenon and has been going on for thousands of years. Prehistoric farmers who slashed down trees and laid out the first rice paddies and wheatfields triggered major alterations to levels of greenhouse gases such as methane and carbon dioxide in the atmosphere, they say.
As a result, global temperatures - which were slowly falling around 8,000 years ago - began to rise. 'Current temperatures would be well on the way toward typical glacial temperatures, had it not been for the greenhouse gas contributions from early farming practices,' says Professor William Ruddiman of Virginia University.
The theory, based on studies of carbon dioxide and methane samples taken from Antarctic ice cores, is highly controversial - a point acknowledged by Ruddiman. 'Global warming sceptics could cite my work as evidence that human-generated greenhouse gases played a beneficial role for several thousand years by keeping the Earth's climate more hospitable than it would otherwise have been,' he states in the current issue of Scientific American.
'However, others might counter that, if so few humans with relatively primitive technologies were able to alter the course of climate so significantly, then we have reason to be concerned about the current rise of greenhouse gases to unparalleled concentrations at unprecedented rates.'
Elaborating on his theory, Ruddiman said: 'Rice paddies flooded by irrigation generate methane for the same reason that natural wetlands do - vegetation decomposes in the stagnant water. Methane is also released as farmers burn grasslands,' Ruddiman points out.
Similarly, the cutting down of forests had a major effect. 'Whether the fallen trees were burnt or left to rot, their carbon would soon have been oxidised and ended up in the atmosphere as carbon dioxide.'
Computer models of the climate made by scientists at the University of Wisconsin-Madison suggest this rise in carbon dioxide and methane would have had a profound effect on Earth: without man's intervention, our planet would be 2C cooler than it is now, and spreading ice caps and glaciers would affect much of the world.
The idea that ancient farming may have had an impact on Earth's climate was given a cautious welcome by Professor Paul Valdes, an expert on ancient climate change based at Bristol University.
'This is a very interesting idea,' he told The Observer. 'However, there are other good alternative explanations to explain the fluctuations that we see in temperature and greenhouse gas levels at this time. For example, other gases interact with methane and carbon dioxide in the atmosphere and changes in levels of these could account for these increases in greenhouse gases.'
Did you see this today?
"Scientists working at the Copan archaeological site in western Honduras said Sunday they have unearthed the 1,450-year-old remains of 69 people, as well as 30 previously undiscovered ancient Mayan buildings."
`snip`
Here is the link
http://news.yahoo.com/news?tmpl=story&u=/ap/20050307/ap_on_re_la_am_ca/honduras_mayan_relics
There once was a lot more going on south of us than is known even today.
That is a vicious Colonialist anti-Nativist revisionist racist myth. The industrious peace loving Indiginous Nations were performing enlightened environmental prescriptive burning of brush to prevent catastrophic wildfires that would have damaged the sacred ancient groves, in return for which Earth Mother and Sky Father sent fat deer to every hearth.
Professor Ward Churchill explained it very clearly in class last quarter, and he should know; he is either 1/16, or 3/16, Cherokee or Cree; unless he is 1/2 Sioux; except for the days he is 100% Upthecreek.
Damn, Blam... you cost me a perfectly good BSometer. I opened this thread before I thought to turn the meter off, and before I knew it, the needle was wrapped around the stop fifteen times. Give a guy some warning... those meters are expensive!
I guess the media would rather have most of the country today covered by glacier. What a bunch of morons
I thought the answer would be these farmers built the combustion engine and air conditioner, I'm so disappointed they only cut down some trees. Holy cow, didn't the glaciers destroy more trees than that, you ever seen trees in glacier areas.
Actually, you are both wrong...
The dinosaurs were killed when ChubbyCheckersaurus introduced a new dance craze... the Twist. The new dance took the Cretacious World by storm. After two weeks of constant twisting, the apatosaurus was too dizzy to graze for food, the Allosauri were to spun out to hunt, and the velociraptors had tripped on their own claws. Within a week, they all died.
Did I mention the maiasaurus rolled over her clutches of eggs?
This is a good argument for thinning forests and harvesting the wood for manufacturing purposes..
Thereby preventing forest fires, and appropriately utilizing wood that would otherwise cause carbon dioxide if left to rot..
Best argument for Forest Management and Utilization I have seen to date...
There's been a few major disasters in our past..
They've killed off major chunks of the world population..
And then there's the plagues.. some major die-offs there as well..
I'm guessing.... ( I admit it, I'm guessing )
There were larger populations in the past than that chart indicates..
It just shows what was left after the disasters at various points in our history..
This may be exaggerated, or overblown, but I seem to remember that the last great plague, in the 13th or 14th century killed off something like 1/3 of the population of europe.. and did similar damage in other parts of the world..
Add those deaths / losses as you move back in time, and the population in ancient times becomes larger..
BTTT!!!!!!
I'm proud of my grandfather for his share of the effort in saving us all!
Remember that 74,000 years ago the Toba explosion left (alive) only 2-5,000 humans worldwide.
There was also a huge genetic split at that time and produced many more 'branches' on the human tree. This occured again about 18k years ago during the Last Glacial Maximum (LGM).
What about all the wetlands that the environmentalist want to preserve? Aren't they Methane generators leading to Global Warming?
Yes, that's like what I was thinking of..
What was the population before Toba?
What about similar global / continental disasters?
Example:
Sea level rise at the end of last ice age..
How many lives can we guess were lost as the Indonesian plateau (savannah? land bridge?) was submerged, isolating the Australian continent and turning myriad Indonesian mountain ranges into islands?
It seems logical to me that the world population has probably gotten fairly large at least once, maybe several times, only to be diminished by some disaster or disease..
(Hope that makes sense..)
Yes, I would say they produce plenty as well..
I guess my question would be, is it significant?
I mean, compared to say, Mt. Pinatubo, is the methane produced by wetlands more than a small percentage of the total gh-gases overall?
And what's the trade-off?
We depend on plant life to create and clean our atmosphere... ( all they way down to plankton )
The whole point of the article is to validate the theory of greenhouse gas emmsions causing Global warming.
If a handful of early Ice Age farmer's crop fields affected the earth thouasnds of years ago, how much more has modern man's industrial revolution caused?
That is the intent of the article.
We all contribute to global warming every time we open the door of our temperature controlled 72 degree environment we call home, and let the heat out.
Now we could all play cave man and test that theory.
On second thought, civilized people need not freeze to death so I am kinda fond of global warming.
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