Slashdot Mirror
Columbus Blamed For Mini Ice Age
DesScorp writes "Science News reports on a story which blames a centuries long cooling of Europe on the discovery of the new world. Scientists contend that the native depopulation and deforestation had a chilling effect on world-wide climate. 'Trees that filled in this territory pulled billions of tons of carbon dioxide from the atmosphere, diminishing the heat-trapping capacity of the atmosphere and cooling climate, says Richard Nevle, a geochemist at Stanford University.' The story notes that the pandemics in the Americas were possibly an example of human climate manipulation predating the Industrial Revolution, though isotope measurements used during research have much uncertainty, so 'that evidence isn't conclusive.'"
It should say "the native depopulation and consequent re-forestation" rather than "native depopulation and deforestation". In current models, it doesn't make sense that deforestation leads to cooling.
If this theory is right, I think a similar effect should have occurred after the black death in Europe. Does anyone know if it got colder at that time?
The Tao of math: The numbers you can count are not the real numbers.
- First, this is all predicated on Europeans moving on a massive scale to the Americas. The author writes "By the end of the 15th century, between 40 million and 80 million people are thought to have been living in the Americas." Given that Columbus sailed in 1492, does anyone seriously believe tens of millions of Europeans moved to the Americas in the next 8 years? Even in the next 100 years? Completely nonsensical numbers.
The 40-80 million population refers to the natives, not the settlers.
- Third, they got the direction wrong: if forests were chopped down, they would have been burned and not allowed to regrow - thus increasing CO2, not decreasing it.
If you read the article, you;d know that the effect is due to the growth of trees in cleared areas, not the burning of trees that occurred prior to that.
No, this is quite interesting.
If true, this means in less than a hundred years enough CO2 was pulled out of the atmosphere to affect the environment. If proven this adds to the evidence that the climate is pretty darn fragile. I haven't read the TFA because I am getting ready to work, but there is one rebuttle and pone possible way to "test" this hypothesis off the top of my head.
The Rebuttle: I thought previous studies claimed the Little Ice Age was more regional than global. I know it affected Europe and played a hand in colonies.
The possible test: Parts of the North East U.S., namely Pennsylvania, were heavily deforested. During the Great Depressing the government sponsored Civilian Conservation Corps. walked across Pennsylvania and replanted large tracks of forest. A half of state worth of new forest popping up should at least have a little blip on CO2 level measurement, right?
by Anonymous Coward: I, for one, welcome the shift from car analogies to pizza analogies. um.. overlords?
Some are worse than others. Some love to paint with a broad brush using open ended phrases like your "Climate Change Skeptics".
Skeptic about which claims? There are hundreds of climate change issues and there equally hundreds of opposing opinions. Each side has their facts so where does a skeptic fall? I tend to agree with some and disagree with others yet under your banner I am lumped in with the kooks.
There is a whole industry out there which only tries to assign guilt, much of it to gain moral superiority but quite a bit is built on making a profit. Climate change discussions didn't get very far until some very large companies learned how to use politicians to make a lot of money off of it. Look at GE, poster child of abusing this process, we give them two billion dollars to further develop wind technologies which is already in their best interest to do so? They then pile on the deductions to have nearly an effective zero rate of taxes?
The real climate skeptics should be applauded because most of science is being used to hide an agenda whose only goal is to pad specific pockets. Its well funded and marketed and much of it has governments behind it because the politicians love money.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
does anyone seriously believe tens of millions of Europeans moved to the Americas in the next 8 years?
No, people do seriously believe the European invasion killed off millions of indigenous people, who, after dying, stopped their agricultural activities, which allowed forests to regrow, which sucked CO2 out of the atmosphere.
This paper contends that that decrease in CO2 cooled Europe.
From TFS: "Tying together many different lines of evidence, Nevle estimated how much carbon all those new trees would have consumed. He says it was enough to account for most or all of the sudden drop in atmospheric carbon dioxide recorded in Antarctic ice during the 16th and 17th centuries."
So yes.
http://en.wikipedia.org/wiki/Year_Without_a_Summer
http://en.wikipedia.org/wiki/1815_eruption_of_Mount_Tambora
Earlier midmillenial cool downs were due to a volcano in Iceland and other solar minimums as well.
Look, I'm infuriated by climate change denying morons myself, but rewriting history and ignoring basic science is not how you defeat those losers. Simple repetition of obvious scientific facts about man made warming is how you defeat oil and coal industry propaganda kool aid drinkers, not reimaging the plot of "Avatar."
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
This is a roundup of a lot of scholarly work on what the Americas were like before Columbus. In short, the book contends that there were an awful lot of people in North America prior to the Age of Exploration who were extraordinarily susceptible to European diseases. While many practiced straight-up agriculture, a lot of others essentially "farmed" wild game - early European colonists into the Ohio Valley noted that the land often looked like European parks (i.e., trees spaced far enough apart that wagons could easily be driven between them, with occasional copses, making perfect habitat for deer), and that an extraordinarily high percentage of the trees that were there were nut-producers (i.e., they planted those and cut down anything else). It also argues that the early explorers (especially de Soto's expedition) weren't making things up when they talked about cities with tens of thousands of inhabitants lining the sides of rivers. When they died en masse, the "old-growth" forests arose.
Now eventually it reaches a stable phase. Trees absorb Y amount of CO2, produce leaves, leaves fall and rot, release Y amount of CO2. Trees die, but get replaced so the forest neither grows nor shrinks. I guess that's what you mean. But the carbon that went originally into making the trees is still locked up in the forest. Burning it will most definitely release carbon into the environment that wasn't free before.
Thus producing the OPPOSITE effect to that posited by the story.
The story speculates that forest cover increased due to depopulation of North America by diseases and weapons brought by European settlers. The resulting increase in biomass was allegedly responsible for a reduction in CO2 leading to global cooling.
The whole conjecture sounds like BS with a politically correct slant. In Europe there was an ongoing deforestation which had commenced a century or so before Columbus, and a considerable deforestation of the Americas started a century or so later. Due to the time scales of forest growth and the probable extent of any net change in forest cover, the effect on climate would have been rather limited (probably negligible).
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
You can see such a dip in the first graphic associated with this paper:
http://cdiac.ornl.gov/trends/co2/lawdome.html
From TFA that 'sudden drop' in CO2 levels equates to 6 - 10 ppm. Given that the current atmospheric concentration is 392 ppm, and in 2009 CO2 levels increased by 2ppm, we're talking about tiny quantities well within the margin of error of the measuring methods used. At worst we're talking about an equivalent to 5 years of increase, based on the 2009 figure, and that was enough to trigger a mini 'ice age'? This is junk science.
It might be, but if the reforestation alone can account for that drop in atmospheric CO2 (that's a lot of forest!), then the change in the landscape itself would certainly have an influence on local climate, possibly enough to influence Western Europe.
Also, don't be so quick to dismiss research based on an article in a popular science magazine: most journalists are incompetent, and will try to get a sensationalist angle out of anything and nothing.
Sceptics of Columbus' plan were on record as saying 'Sure you'll be able to sail around the world, when hell freezes over'. He proved them wrong (sort of), and hey presto! Ice age. Coincidence? I think not!
Previous climate change, along with continental drift, continental forest fires, and the other big changes you invoked - all happened over thousands and millions of years. The current climate change you deniers no longer bother to deny is actually in progress is happening over just a few decades and centuries. Which is totally unprecedented.
OK then. What caused the "little ice age" to begin with? Didn't it start within a few decades or centuries? If we are to assume that Europeans deforested the Americas causing an end to the little ice age, then how did it ever start since Europeans had been deforesting Europe for centuries? Shouldn't it have been warmer in 1600's than it was in the 1400's, which should have been warmer than the 1200's and then the 800's and so on? How on earth did a little ice age form in the 1800's? Also, what ended the "big ice age" about 10,000 before Columbus was ever born?
See, this is the problem with the whole AGW argument. Man spots a trend like, the climate is warming or it's raining, and then wonder what HE did to cause it. Maybe, just maybe whatever change happened with no help from man at all. Maybe that dance really didn't cause it to rain and it was going to rain whether you danced or not.
Correlation does NOT equal Causation.
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
Article's theory: An area the size of california was reforested over 200 years causing the little ice age
Your theory: removal of X amount of forest over 200 years should have resulted in Y amount of warming which we didn't see. We actually saw a temperature change of Z.
You need to figure out what X , Y and Z are before making that a legitimate argument. The article has real numbers and real research behind it, your speculation does not rise to the level of a rebuttal.
Well.. maybe. Or Maybe not. But Definitely not sort of.
More to the point, the idea that somehow the Medieval Cooling Period was caused by the discovery of the New World is yet another example of the kind of "Pay no attention to the man behind the curtain" pseudo-science that passes itself off as climate science.
Most of it is now driven by either politics (IE: People with a socialist/communist/fascist agenda that want to use climate science as a convenient crisis under which they can obtain power. See: Harry "Never let a good crisis go to waste" Reid.) or by scientists attempting to obtain/increase their funding, much of which is obtained via the former group of power-mongers.
It's part of the "perfect circle" of deceit and corruption that is at the heart of the modern left and modern climate science. Most Americans have caught on to the game by now, which is why 70% (and rising) no longer believe a word from the climate scientists' mouths. People hear the words "Climate Change" or "Global Warming" (or whatever the term du jour is) and they just roll their eyes and stop listening.
The really sad part is that it has inculcated in large parts of the American populace a distrust of scientists in general, particularly if they are in any way connected with the climate science field.
Frankly, the climate science field has been nothing but a disaster for science as a whole. It needs a hard reset, with all current scientists retiring, and all existing data deleted. We need to start over on this and do it right. Now, whether that is actually possible, I don't know. Probably not. But I don't see any other way of making it trustworthy again.
Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
I live amongst them, along with millions of other people. Here in New England, the history is this: Prior to European settlement, 75% of the land was covered in trees. The Europeans showed up, cut down the forests and made farms of the land. At this point, roughly 25% of New England was forested, the other 75% was largely farms. Later, the farmers moved to the mid west and west, abandoning the farms in New England, which were a bitch to farm because of the rocky soil. The farms were abandoned and trees grew up in their place. That's why you can hike through forests in New England and find old foundations and very long lines of stone walls in the middle of nowhere. Back in the day, those forests were "somewhere." Even with our "sprawl" in New England, roughly 75% of the land is forested. I can attest to this as I live in a forested burb. Deer, turkeys, foxes, etc. routinely walk through my yard. Don't believe me? Then just pull up http://maps.google.com/ and search on New England. Then look for deforested land... if you do the visual math, you'll see that it is mostly still forested here.
Brawndo: It's what plants crave!
Let me see if I understand the logic:
Indians deforested continent.
Columbus comes.
Indians die.
Forests grow back.
Temperature plummets.
Little Ice Age appears.
The only logical conclusion is that we're supposed to start slaughtering indigenous peoples again?
I mean, sure, if science says we have to.
-Styopa