Research team suggests European Little Ice Age came about due to reforestation in New World

Oct 17, 2011 by Bob Yirka report

(PhysOrg.com) -- A team comprised of geological and environmental science researchers from Stanford University has been studying the impact that early European exploration had on the New World and have found evidence that they say suggests the European cold period from 1500 to 1750, commonly known as the Little Ice Age, was due to the rapid decline in native human populations shortly after early explorers arrived.

Following up on their paper published in 2008, the team has now brought their findings before the . The researchers say that the population decrease, which came about due to the introduction of previously unknown diseases, led to the rapid of the Americas. This led to a sudden increase in the amount of carbon dioxide being pulled from the air, which meant the wasn’t able to hold as much heat, which led to colder air covering Europe.

The team, led by visiting scholar Richard Nevle, came to this conclusion after analyzing charcoal remnants in soil and lake sediments left behind by early American inhabitants as they burned forests to make room for farmland. They found that starting approximately 500 years ago, the charcoal accumulations came to a virtual standstill, coinciding with the death of native peoples.

Nevle et al then got out their calculators and crunched the numbers. They estimate that for a population of some 40 to 80 million indigenous people, the total amount of deforested land would likely have amounted to something the size of California. And since most estimates suggest that close to 90 percent of the native peoples died or were killed after the Europeans arrived, that meant most of that land returned to forest. That many trees, they say, all of a sudden appearing, almost as if out of nowhere, could have resulted in a loss of some 2 to 17 billion tons of carbon dioxide from the air.

To further bolster their argument, they say that core samples taken from the ice in Antarctica have air bubbles in them that show a reduction of by 6 to 10 parts per million between 1525 and the early 1600s.

Of course this isn’t concrete proof that humans caused the , as others in the field point out. Events such as volcanic eruptions, solar flares or even colder ocean currents could also be at play. But so far, the evidence is certainly intriguing, pointing out that human activities, even those that are inadvertent, could be the cause of serious global climate changes.

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R2Bacca
3.4 / 5 (5) Oct 17, 2011
One sticking point - Europeans themselves cleared land as they took over... so you have to wonder how fast reforestation really could have occurred. This seems to be based on speculation for the most part to me. A reduction in CO2 around the same time doesn't prove causation, only correlation.
sstritt
3.7 / 5 (9) Oct 17, 2011
Are they seriously asserting that 6-10 ppm reduction caused the little ice age? absurd!
Ethelred
3.7 / 5 (10) Oct 17, 2011
Europeans themselves cleared land as they took over.
That came much later and much slower than the die off. The Mississippi Valley was wiped out in the 1500's and Europeans didn't come for farming till after the American Revolution and the Louisiana Purchase.

Ethelred
kochevnik
3.5 / 5 (6) Oct 17, 2011
Stanford graduate students must be hoarding some fine Ganja this year. Could that bring on a double-dip ice age?
Pirouette
2.1 / 5 (7) Oct 17, 2011
It's all conjecture. . . .the article clearly states, "Of course this isnt concrete proof that humans caused the Little Ice Age, as others in the field point out. Events such as volcanic eruptions, solar flares or even colder ocean currents could also be at play." This is not to say that humans are entirely innocent. I've seen grown men spill oil out of their crankshaft onto the ground deliberately and act like it was nothing. But to say that wholesale climate change is caused by man in great proportion is stretching it a bit. And the Earth has ways to clean itself up. It just needs time. People like Al Gore are riding this caboose as far as they can go. . .and pocketing the change, of course.
TheFlynn
3 / 5 (6) Oct 17, 2011
Native Americans burned forests down to make way for agriculture? First I've heard of this... You know what this web site needs? A BIBLIOGRAPHY.
Ethelred
3.7 / 5 (6) Oct 17, 2011
Flynn

That is a standard way across the world to make room for crops in forested areas. Burning as a way to control the environment has been done by humans for millenia at the very least. Much easier than cutting it down. The ash is good for the crops.

Works best with brush and young trees that were young because of the previous burns either human or natural. Continued burns over time will burn the edges of the forest opening more land for agriculture.

You have most likely heard of this before unless you are VERY young. Its called slash and burn agriculture. You just hadn't heard the Amerinds did it for the simple reason that most the ones that did so DIED in those plagues.

With the advent of horses the Plains Indians took over the middle of America and they didn't bother with agriculture.

Ethelred

Ethelred
3.1 / 5 (12) Oct 17, 2011
It's all conjecture.
No. It is based on pretty good evidence. Personally I doubt that would be sole cause but it is interesting.

But to say that wholesale climate change is caused by man in great proportion is stretching it a bit
No. SOLE cause yes, but a major cause? I see no reason to claim human released CO2 isn't a major cause.

And the Earth has ways to clean itself up. It just needs time.
The Earth isn't an entity. There are processes that cover up messes and use up CO2 but there is nothing TRYING to CLEAN up except us.

Gaia is crap though most people into Gaia think AGW is real so you must be one of the few or you are into sloppy writing. Probably the latter.

At present we humans are adding CO2 to the atmosphere faster than it is being removed by natural processes. Time is NOT going to heal this if the rate of human CO2 stays the same and it is getting HIGHER not lower at present. Until the rate goes down CO2 will increase in the atmosphere.

Ethelred
turnup4thebooks
4.4 / 5 (5) Oct 18, 2011
The 'little ice age' started as early as the 14th century and was due to decreased sun spot activity.
Ethelred
2 / 5 (4) Oct 18, 2011
Possibly but there isn't any evidence to support that claim and there is evidence of that later decrease in CO2 which is a greenhouse gas. There just wasn't anyone keeping track of sunspots in the 1300s. Later yes but not back then.

It is entirely possible that both CO2 and a decrease in Solar activity were involved. Now IF there is evidence of the Southern Hemisphere cooling at the same time as the Northern Hemisphere, and to the same degree, that would point towards the Sun. If it was purely a Northern phenomena then CO2 would be much more likely.

And I think you might be mixing up two separate cooling periods.

http://en.wikiped..._Ice_Age
It is conventionally defined as a period extending from the 16th to the 19th centuries,
There is support for a world wide cooling but NOT as far back as you trying to push it. 1500 seems about it.

Ethelred
Dichotomy
3.7 / 5 (3) Oct 18, 2011
I think the authors of this need to spend quite a bit more time learning about North American History. Their facts are off in the timing (the natives weren't suddenly wiped out in a span of 50 years from disease, it was more gradual over a few hundred as natives and colonists were exposed to each other, so the available space for trees to suddenly start growing wasn't significan) Also, remember the natives who hunted (about 80%) and migrated with their food vs. the ones who settled and engaged in agriculture (the other 20%). Hunting tribes didn't bring down forests. Since the natives themselves weren't about "sharing the land" with other tribes due to competition for resources, the amount of land "deforested" by the natives was minimal. Lastly, deforestation isn't in line with virtually all native religious beliefs about respecting the land and nature. Bottom line is that the authors of this study seems to be using data in an attempt to justify a pre-determined conclusion.
omatumr
1 / 5 (5) Oct 18, 2011
1. Are they seriously asserting that 6-10 ppm reduction caused the little ice age? absurd!


1. You are right. The AGW fable advanced by world leaders, Al Gore, and the UN's IPCC does not explain current global temperatures.

"Deep roots of the global climate scandal (1961-1971)"
http://dl.dropbox...oots.doc

So public funds went to needy Stanford students to find "evidence" somewhere that CO2 caused global warming or the absence of CO2 caused global cooling.

See 1961 warning of this government-funded "scientific-technological elite":

www.youtube.com/w...ld5PR4ts

2. Stanford graduate students must be hoarding some fine Ganja this year.


A reward for using calculators to crunch numbers for Big Brother.

Science marches on!
Oliver K. Manuel
http://myprofile....anuelo09

See: "Video summary of research career (1961-2011)"
http://dl.dropbox...reer.pdf
Ethelred
3.7 / 5 (3) Oct 19, 2011
Their facts are off in the timing (the natives weren't suddenly wiped out in a span of 50 years from disease,
In the Mississippi Valley it may have been as little as a few years.

it was more gradual over a few hundred as natives and colonists were exposed to each other,
That is after the intial small pox plague. I have never seen anyone claim that hundreds of years were involved. One hundred years is the longest I have seen. When Pissaro conquered the Incas the death rate from disease was around 50% over a few years and the deaths had started even before he arrived.

Hunting tribes didn't bring down forests.
True but there was more hunting after the horse was introduced.

Lastly, deforestation isn't in line with virtually all native religious beliefs about respecting the land and nature.
Sometimes. The Anasazi deforested their territory. In other areas that would have been more difficult except by fire.>>
Ethelred
3 / 5 (2) Oct 19, 2011
Bottom line is that the authors of this study seems to be using data in an attempt to justify a pre-determined conclusion.
The core samples support them to at least some degree as do the charcoal findings. I have noticed that pre-determined conclusion are VERY popular on BOTH sides of this issue.

I am trying to look at the evidence. I see a lot of people trying t deny or even invent evidence.

Ethelred
Ethelred
3.7 / 5 (3) Oct 20, 2011
Oliver recently made the mistake of actually posting a link to the Biblderberg Paper he rants about.

http://adsabs.har....3....5G

Now we know that Oliver didn't read it as it doesn't have any of the claims he makes about it. Its just a model of the photosphere and chromosphere that reached no definite conclusions, made no claim that the Sun is completely stable, has nothing to do with any global warming theory, and isn't part of the standard model he hates so much.

It is over 40 years old and had no computer modeling, no input from shady politicians, no Al Gore, no nothing that supports his bizarre attacks on it. Heck it doesn't even deal with the Sun's core in anyway and thus could have been written exactly the same way if they had used his self-contradicted Pulsar Sun silliness.

This is similar to the Kissinger letter he linked to. That too did not have the support he claimed was there.

Ethelred
Chuck_Coffer
1 / 5 (1) Nov 01, 2011
"But so far, the evidence is certainly intriguing, pointing out that human activities, even those that are inadvertent, could be the cause of serious global climate changes."

Pointing out? Making up is more like it.
Ethelred
3 / 5 (2) Nov 01, 2011
Pretty sad first post there.

Could you post some actual evidence to support that statement. Or did you just make it up?

Ethelred
Chuck_Coffer
1 / 5 (3) Nov 02, 2011
Since anything said by anyone calling themselves a "scientist" is called "evidence" by the guillible, what would be the point? There isn't a single bit of evidence to support the idiotic doomsday fantasy that says "inadvertent human activity could be the cause of serious global climate changes" and 5000 years of human history showing it to be absolute nonsense. You idiots live in your imagination and ignore the obvious.
What a sad way to waste a mind.
Ethelred
5 / 5 (2) Nov 02, 2011
is called "evidence" by the guillible
Looks like any evidence you don't like becomes "evidence".

what would be the point?
Something resembling actual support to a post that insults people for saying things you don't like to hear.

isn't a single bit of evidence to support the idiotic doomsday fantasy
Correct. There are a lot of bits. Its not doomsday, just potentially bad. I am more interested in the melting ice then the other parts of climate change.

and 5000 years of human history showing it to be absolute nonsense
Idiot. Human history shows that glaciers melted. The flood of the Black Sea is most likely is the source of the flood stories in the Eastern Mediterranean.

You idiots live in your imagination and ignore the obvious
Speaking of idiots, you can't support you insults with evidence. Which is what makes you an idiot. Worse, have CHOSEN to be an idiot.

What a sad way to waste a mind
You are a sad waste of a human being.

Ethelred