Study: Global warming sparked by ancient farming methods

[Libertas1776]

Source: CNN

(CNN) -- Ancient man may have started global warming through massive deforestation and burning that could have permanently altered the Earth's climate, according to a new study by researchers at the University of Virginia and the University of Maryland-Baltimore County <snip> over thousands of years, farmers burned down so many forests on such a large scale that huge amounts of carbon dioxide were pumped into the atmosphere. That possibly caused the Earth to warm up and forever changed the climate.

<snip>

Lead study author William Ruddiman is a professor emeritus of environmental sciences at the University of Virginia and a climate scientist.

<snip>

Ken Caldeira, a climate scientist at the Carnegie Institution's Department of Global Ecology in Stanford, California, is among those who disagree with Ruddiman. He said Ruddiman is "exaggerating the importance of early man."
Caldeira told CNN that while ancient farmers may have played a tiny role in climate change, "it just wasn't a significant factor."
He added, "There are actually studies showing if you cut down forests for farmland, you actually cool the planet, because of the glare from the cleared land."


Read more: http://www.cnn.com/2009/TECH/science/08/18/ancient.global.warming/index.html

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It was only a matter of time before somebody passed the buck of the origins of global warming back to where it belongs...farmers from some six millenia ago. :sarcasm:

To paraphrase Moe Syzlak: Ancient fa'mers! I knew it was them! Even when it was the bears, I knew it was them!

[Mythsaje]

1. Yeah, because stray lightning bolts NEVER burned down whole forests

before man got into the act.

Nope.

Never.

/sarcasm

[dysfunctional press]

2. how does the 'little ice age' fit into that scenario...?

burning fossil fuels on a grand scale is what got things going.

[MajorChode]

3. Some believe it fits quite well

Almost a quarter of the world's population died as a result of the bubonic plague in the middle ages and this includes a much higher percentage in Europe. The resulting reforestation and reduction in carbon dioxide levels is thought to be a contributing factor in the so-called "little ice age."

[Odin2005]

10. The Little Ice Age started before the Black death.

The first symptom of the Little Ice Age was a massive famine in Europe in the early 1300s, a generation before the Black Death, and in the decades before that increasing amounts of ice in the North Atlantic, making it harder to get to Greenland.

[damntexdem]

22. Single-cause explanations don't generally work.

It would be amazing if such factors as massive clearing of land, most often cutting down of forests, for agriculture didn't affect the climate. Whether thousands of years ago, or more recently, as with the clearing of forests from much of England.

On the other hand, massive mining of carbon and its release into the atmosphere as carbon dioxide has had a much, much greater impact -- bringing on our current climate-change crisis. That's our problem now. It's not that a single factor affects the climate, it's that we have introduced such a massive one that it overwhelms lesser factors.

[MajorChode]

28. Thus "contributing factor"

You also have solar and volcanic activity at the time. Personally I don't buy the reforestation causation, but nobody really knows what actually caused the so-called "little ice age", so there's lots of speculation out there.

[Odin2005]

29. I've read some evidence of a 1500 year cycle.

But this was in a book from the 1980s called The Co-Evolution of Earth and Life, a massive tome that was THE comprehensive book on Paleoclimatology at the time, and notable by the authors' acceptance of many aspects of James Lovelock's Gaia Hypothesis, which was important of the Gaia Hypothesis going mainstream.

[Wizard777]

4. The Eradication of Marijuana at the advent of the automobile is the biggest environmental crime.

Funny thing about bionomics. You really only have to remove one species from an ecosystem to get the whole thing to collapse.

[Delphinus]

8. I don't know a thing about bionomics

(never even heard the word before) or the eradication of marijuana (although I do believe if we sold mj over the counter like booze life would be a whole lot better in a whole lot of ways), but I do see what you say with everything being interconnected. All it takes is one thing ...

[Wizard777]

9. Basically a new word for ecology. But it's more accurate than ecology in a practical sense.

Ecology is a study of relationships between organisms and their environments. But Bionomics is more of a look at ecology through the eyes of an Economist. With Bionomics your look more at the careful, thrifty management of biological resources. Ecology tends to be more theorem oriented and Bionomics tends to be more practicum oriented. Ecology and Bionomics are considered to be synonymous. But they're really not.

[old mark]

5. Actually, earth's climate was never stable for very long - even

before the dinos were around, it had changed many times and will continue to do so with or without us.

mark

[FarCenter]

13. An for the last 2 million years, the climate has been mostly glacial

Mostly glacial periods lasting 100 to 200 thousand years, interspersed with warm periods of 10 to 20 thousand years.

We are currently in the warm phase of what is clearly a bistable climate system. It is unclear whether anthropomorphic warming will result in a permanent warm phase, ending the cycles of glaciation, or whether it will just tip the climate system into the glacial phase.

[damntexdem]

23. True -- but we've set off a change that means that future chanes may indeed be without us.

And without much of the biological diversity that heretofore accompanied us.

[old mark]

30. Well, it got the dinosaurs, too, and they didn't even drive.

Must have made some horrible farts.....


mark

[aquart]

6. Who funded this study?

[elocs]

7. The trouble with the "who funded this study" attitude

is that if it is funded by "our" side, then it is valid. If it is not, then it is not valid. The trouble is that what if the study was done by a neutral group with a good reputation. I don't necessarily and routinely believe that findings that do not agree with mine are because someone has an agenda. The bottom line is that one way or another, now or many, many years ago, man could impact the environment.

[Odin2005]

11. The "Who funded the study" mindset is dangerous enemy of objectivity.

It leads to people dismissing facts they don't like as being part of an agenda.

[sofa king]

21. It's a question worth asking, though.

UVa is a state (well, Commonwealth-) funded university, but it's also known as the conservative hotbed of central Virginia. Recall that the 9/11 Commission fixer, Dr. Philip Zelikow, is a UVa professor, which if you ask me is an automatic credibility issue.

Ultimately, I help pay for that university, and I'd like to be certain that it practices the viewpoint impartiality that it claims to practice.

[damntexdem]

24. However, it IS an essential question, because there has been too much science-funding hanky panky.

We have learned the hard way to be doubtful about 'science' funded, for example, by tobacco companies or coal companies. It is now required scientific ethics to be clear about how one's work is funded. True, good science COULD be done under funding from an interested party -- e.g., a tobacco company. But there is doubt that it would be allowed by the funder to freely ask the questions nor to truly go where the answers to those questions led. At the very least, findings would need to be vetted in much greater detail than might otherwise be employed for peer review.

[WriteDown]

12. Hunters and gatherers. nt

[Javaman]

14. Okay, so by their logic...

5-7 thousand years ago, the population of the earth was roughly 4 million people.

if 4 million people burning wood caused global warming, one would thing that an earth with 7 BILLION people burning wood, coal, natural gas and oil would no doubt make it a hell of a lot WORSE.

their argument fails.

global warming and the particles per million rise in direct relation to the rise in earths population. More people, more pollution, more crap in the air = global warming.

the new repuke deniers screed: it ain't our fault it was all those ancient ignorant bastards!!! yeah, that's it!!!

:banghead:

[Orsino]

15. I don't see what the big deal is.

Nothing in the article disputes that global warming has been greatly accelerated by the burning of fossil fuels. That the trend may have begun earlier, after millennia of slash-and-burn by much fewer people, seems no great stretch.

I won't dispute, though, that some wingers wont' find a way to twist this story to their own ends.

[Javaman]

16. The big deal is this...

back then even as short as 200 years ago, the population was such and the burning was such that the earth could properly absorb what ever carbon we humans put in to the air.

We are approaching, if we haven't already arrived, negative feed back. The point where the oceans and plant life of the earth are no longer able to absorb anymore CO2.

That's why their argument about GW being caused or started by civilizations 5-7000 years ago is total and complete bullshit.

it's just more creative research that tries to take the onus off of modern society and put it on some other era or other people so the right wing has yet another excuse not to take responsibility for their contribution to GW.

It goes like this:

talking point #1) it's not our fault, this started thousands of years ago. #2) We can't do anything about it, it started so long ago, it's now impossible to turn this ship around so why penalize corps or business now? #3) sure we maybe contributing now, but the worst of it took place even before the industrial era.

Now why you see this bullshit article is a big deal?

Just another arrow in the rights quiver to use so people don't have to take responsibility for their actions.

[Orsino]

18. At some point, we have to stop being afraid of facts...

...though you are correct that someone will try to use this to dilute the strong connection between fossil-fuel combustion and climate change.

The study doesn't seem to be bullshit--though I'm not sure whether it points to valuable lessons for today and tomorrow.

[Javaman]

19. whatever. your facts and mine seem to differ over one simple issue.

I supply them while you give only opinion.

tootles.

[Orsino]

20. We seem to be agreed on the facts...

...and differ only on a matter of opinion.

[damntexdem]

26. Back 200 years, even back 50 years, it was ASSUMED that the earth could absorb the CO2.

That doesn't mean that it could. That would depend on many other factors, such as natural releases of gases, droughts, and so on. True, the massive releases of the recent past overwhelm any natural ability to absorb greenhouse gases; but it is very likely that much-smaller releases hundreds or thousands of years ago sometimes had major effects, especially taken in conjunction with natural factors (which are likely overwhelmed today).

[dipsydoodle]

17. There are many stories in the Naked City

and this is one of them.

[blueworld]

25. It figures CNN would jump on this - Lou Dobbs? Bunny Blitzer?

I can't bear to read the article yet, but I will & thanks for posting. I never realized there were enough ancient farmers (OOK Perdue?) slashing & burning so many ancient forests with hand tools and that's why the air in China is brown. What were they growing, ancient corn or ancient hemp?:banghead:

[damntexdem]

27. Another issue is that with today's massive population, 'ancient farming methods' have greater effect

Thus, slash and burn being carried out today is on a much-greater scale, destroying major swaths of rain forests that were heretofore largely unthreatened.