Changes In Earth's Orbit Were Key To Antarctic Warming That Ended Last Ice Age 180
vinces99 writes "For more than a century scientists have known that Earth's ice ages are caused by the wobbling of the planet's orbit, which changes its orientation to the sun and affects the amount of sunlight reaching higher latitudes, particularly the polar regions. The Northern Hemisphere's last ice age ended about 20,000 years ago, and most evidence has indicated that the ice age in the Southern Hemisphere ended about 2,000 years later, suggesting that the south was responding to warming in the north. But new research published online Aug. 14 in Nature (abstract) shows that Antarctic warming began at least 2,000, and perhaps 4,000, years earlier than previously thought."
Climate change is human-caused, full stop (Score:5, Funny)
It's Cavemanthropogenic Global Warming, if you want to get technical.
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Well, there's not unreasonable evidence that early human slash-and-burn farming caused a reduction in important negative feedbacks (vis-a-vis forests) and the carbon cycle. But that has basically negligible effect compared to the rates of change (and rates of change of rates of change) seen since 1800.
Break the Ice (Score:2, Funny)
Allow me to break the ice with the first post
Oh god... (Score:1, Insightful)
Cue unrelated arguments about modern global warming... time to flee Slashdot for a few hours....
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But did they mention Solar caused Global cooling during the Maunder Minimum?
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You got a flamebait mod.
Should have been +5 insightful.
After all the article itself was posted as troll/flambait.
Ice ages are caused by planetary wobbles (Score:3, Insightful)
But warming is caused by man.
Got it.
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If you have an actual point to make about how hundreds of climate scientists are wrong, please cite your data. Otherwise you are just insinuating that hundreds of educated people are missing something that you see... as opposed to hundreds of educated scientists knowing something about how and why these occurrences are different and can have different causes.
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The fundamental hypocrisy here is one that is necessary to the scientific method. You must simultaneously be willing to accept that some components of a branch of study are flawed enough to warrant whatever hypothesis, experiment, or observation you are doing, while still believing in the fundamental soundness of the scientific method, and the general accuracy of most results, which form the basis of your own study.
This is a case where they're just being intentionally obtuse, and have nothing interesting t
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How about thousands of well documented papers, all carefully reviewed, many retested with other instruments, based on fundamentally valid physics, with no meaningful contrary assessments?
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Generally speaking, the people who write the papers are the same cast of characters who do the reviews on the papers. Its a fairly incestuous process, so I don't put a lot of stock in "peer review" when it comes to something as unphysical as climate science. Peer review in general, in all sciences, is also undergoing a kind of crisis of confidence. http://www.the-scientist.com/?articles.view/articleNo/34518/title/Opinion--Scientific-Peer-Review-in-Crisis/ [the-scientist.com]
People treat climate science like it was a hard scie
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yes, the same 'incestuous process' that brought you physics, mathematics, astronomy (not astrology), engineering, medicine, virology, genetics...
yeah, the scientific method, publication and review, what a fail
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In all of those cases factual observation+results were the name of the day. In the field mentioned above, 99% of it is based on computer models. The same models that can't predict the path of a hurricane, or whether it's going to be pissing rain on Canada for the next 14 days(though common wisdom says it will be).
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The same models that can't predict the path of a hurricane, or whether it's going to be pissing rain on Canada for the next 14 days(though common wisdom says it will be).
Why did you say that. Even you know why it's not worth saying that.
Dishonest people make dishonest arguments.
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The purpose of peer review in general is not to determine if a paper is right or wrong but to make sure there are no obvious mistakes or elementary errors that would make it a waste of time for others in the field to read it in the first place.
And I think that climate science is not nearly as soft as you seem to think it is. Yes, it is very complex but the interactions are all physical and it's probably not necessary to know every single one. The top 10 or 20 probably cover well over 99% of the effects.
Not with the AGW religion! (Score:2)
The purpose of peer review in general is not to determine if a paper is right or wrong but to make sure there are no obvious mistakes
The obvious mistakes were pointed out repeatedly, but still the papers were published...
The point of the peer reviewers in regards to AGW was always "No paper from anyone committing blasphemy against our religion must ever be allowed to publish", regardless of the science therein.
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What obvious mistakes would those be?
I know the supposed suppression of papers is a meme on the climate contrarian side but it doesn't hold water as far as I can see.
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The obvious mistakes were pointed out repeatedly, but still the papers were published...
[Citation Needed]
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Let's get Congress and 5th graders ( is that redundant? ) to conduct peer review on scientific papers.
Re:Ice ages are caused by planetary wobbles (Score:5, Insightful)
And it won't come because some people have decided that science is great when it provides computers, internet and porn on DVD but is somehow stacked full of blithering idiots when it comes to climate change.
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warming is caused by many things.
no one has ever said that only man causes it.
however all of those things cause warming over a very very long time scale. except man.
which is why the very very fast warming we've seen is attributed to man.
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You might want to look at two things. One is the actual thermal record over geological time, which shows intervals of extremely rapid natural warming and cooling. Second, you might want to consider the fact that much of that record is essentially smeared out by imprecision in the proxies used so that one is comparing two different kinds of averages -- one averaged over a very short time interval, and another where the average might well be over a period longer than the entire time we have had thermometers
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From:
http://en.wikipedia.org/wiki/Little_Ice_Age [wikipedia.org]
Decreased human populations
Some researchers have proposed that human influences on climate began earlier than is normally supposed and that major population declines in Eurasia and the Americas reduced this impact, leading to a cooling trend. William Ruddiman has proposed that somewhat reduced populations of Europe, East Asia, and the Middle East during and after the Black Death caused a decrease in agricultural activity. He suggests reforestation took place,
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So you're saying that the Bern model for CO_2 sequestration is wrong, then? I don't think we know enough to say that it is right OR wrong yet, and won't for some time yet, but sure, it might be wrong.
However, you need to actually do the numbers before you conclude that killing off 1/3 of everybody from India to Iceland might have sequestered "huge amounts of CO_2" and you might point out some evidence that this occurred in the various CO_2 proxies before basically making something up to explain something t
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The economy of that whole section of the world collapsed, farmland away from population centers was abandoned and reverted to forest. Travelers reported that a squirrel could travel from Vienna to Warsaw and never have to leave the trees, a region that was heavily farmed both before and after the population collapse.
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Heavily farmed? You might take a glance at the population of the world then and now. I'll help:
http://en.wikipedia.org/wiki/World_population_estimates [wikipedia.org]
As you can see, even though the black plague may have killed 1/3 of the world's population, it didn't kill them all at the same time, and it isn't even clear that the world's population ever actually receded during the events, at least according to this table (which also exposes a fundamental limitation -- look at the spread in estimates for t
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Seriously? There is a 0.4 C spike from 1910 to 1940, compared to 0.6 C from 1970 to 2000, and you think that the extra 0.2 C is sufficient evidence of runaway anthropogenic global warming, given a non-anthropogenic spike 2/3 as large in the only two samples of spikes we have in the moderately reliable instrumental record e.g. here: http://commons.wikimedia.org/wiki/File:Instrumental_Temperature_Record.png [wikimedia.org]?
Note well that I am not claiming that the latter spike is or isn't natural. I'm asserting that the i
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Or, you know, you might want to look in it, since if you are basing your theory on these things, then it's up to you to do the research which demonstrates how they are significant.
This statement right here is the problem with most people. They, like you, dont understand what the fuck they are talking about.
All the long-duration proxies (more than a few hundred years) do measure as an average over hundreds and even thousands of years because there is too much short term noise in the signal. Thusly statements about the rate of warming on short time scales cannot be made about periods in the past more than a few hundred years. He doesnt need to look into why this is because its prove
Stellar explosions are caused by natural forces (Score:2)
But Hiroshima was caused by men.
Got it.
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Isn't it inconvenient when people who think differently than yourself speak up?
Other religious fanatics have the same reactions when their ideals are challenged.
I have found through the years, "shut up" is the sign of a weak and easily manipulated mind.
The Inconvenience of Sarcasm (Score:1)
What is inconvenient is when people who have nothing to say -- nothing better than sarcasm and "meh", anyway -- insist on saying it anyway.
Example: "But warming is caused by man. Got it."
Tell me something interesting, useful, relevant, meaningful. Then you get my attention and respect, regardless of how similar or different my opinion is from yours.
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Tell me something interesting, useful, relevant, meaningful.
ok, here goes-
The parent started his comment with the title of his post, so it would read as follows: "Ice Ages are caused by planetary wobbles, but warming is caused by man. Got it."
Yes, it's sarcastic and not really much of a post, but it does illustrate the problem with the entire "debate" about how climates change on Earth. Perhaps if you took the time to explain this apparent conflict of information you'd be helpful yourself. As it is, you've offered even less to the discussion than the initial sarcast
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Tell me something interesting, useful, relevant, meaningful.
ok, here goes-
The parent started his comment with the title of his post, so it would read as follows: "Ice Ages are caused by planetary wobbles, but warming is caused by man. Got it." Yes, it's sarcastic and not really much of a post, but it does illustrate the problem with the entire "debate" about how climates change on Earth.
Yes, indeed it does. It tells us that the "skeptics" can't tell the difference between starting an ice age and ending an ice age. And the replies defending the post confirm that.
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Isn't it inconvenient when people who think differently than yourself speak up?
No, it's just inconvenient when people who don't think speak up.
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The original comment, though sarcastic does point out a massive inconsistency
The original comment didn't point out absolutely anything of value.
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The problem we have with your thinking is that climate scientists are way ahead of you on thinking those thoughts about what comes into play in climate change and have already examined that possibility. You would know that if you seriously investigated climate science so when you suggest that they missed that it just shows your ignorance.
Regarding the "planetary wobbles" (collectively known as Milankovitch Cycles [wikipedia.org]) the shortest of the different factors that goes into it is around a 26,000 year cycle so a ma
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Re:Ice ages are caused by planetary wobbles (Score:5, Insightful)
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Isn't it inconvenient when people who think differently than yourself speak up?
No, it's just telling when someone can't even tell the difference between "starting" something and "ending" something. That clearly shows he's not into "thinking differently" but into "not thinking at all".
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It was plenty insightful, you just didn't like the point. The ~comment of "It's the republicans fault, or Bush's fault" is a no fail 5 insightful on this pitiful website so your argument is ludicrous.
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There is little insight in a sarcastic comment expressing a common point of confusion: that climate change processes on the scale of tens to hundreds of thousands of years are going to matter to what happens in the next century or two.
I don't mind sarcasm if it's founded on an insightful understanding, but this isn't. It's just dumb. It promotes confusion, not understanding. Here, I'll rephrase it for you with an analogous situation:
"Tides are caused by the Sun and Moon"
"But waves are caused by wind"
"Got
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Let me translate your comment: *I'm smart and informed and my opinion counts, you're stupid and we don't want your opinion*.
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You hear that a lot, do you?
Well, yes - I browse Slashdot and don't filter out AC's.
Which is also how I learned you have weak minds...
Don't let ice build up! (Score:4, Funny)
I mean, you don't let ice build up on your roof, in your freezer, or on airplanes... ice is always bad unless it is in my drink!
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More margaritas for everyone, to save the planet!
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All that ice on the poles made the Earth all wobbley, which led to Bad Things. We should de-ice the planet, as a precaution so it doesn't happen again!
I mean, you don't let ice build up on your roof, in your freezer, or on airplanes... ice is always bad unless it is in my drink!
Hmm. So these orbital wobbles... are they nature's defrost cycle?
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Before anyone drags climate change into it.. (Score:5, Informative)
FTFA: "Changes in Earth's orbit today are not an important factor in the rapid warming that has been observed recently...Earth's orbit changes on the scale of thousands of years, but carbon dioxide today is changing on the scale of decades so climate change is happening much faster today."
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you commit the fallacy of asserting the consequent
A critique (Score:1)
Parent post commits a fallacy of equivocation, if I read its interpretation right. If not, then there is no fallacy at all. Either way there is a distinct lack of either logic or reading skill present. The post also lacks punctuation and a failure to discern the difference between 'affirming' and 'asserting'.
2/10
Would not read again.
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FTFA: "Changes in Earth's orbit today are not an important factor in the rapid warming that has been observed recently...Earth's orbit changes on the scale of thousands of years, but carbon dioxide today is changing on the scale of decades so climate change is happening much faster today."
Yeah, I read that part too, and it's the only part of the article that bothered me. It was something of an unnecessary sensationalist jab in an otherwise informative article. Had they left that last sentence off, it would not have been any less informative, without dragging in T. J. Fudge's poke in the eye of the anthropogenic global warming controversy. Anything to bait the clicks, I suppose...
Re:Before anyone drags climate change into it.. (Score:4, Insightful)
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It was something of an unnecessary sensationalist jab in an otherwise informative article. Had they left that last sentence off, it would not have been any less informative, without dragging in T. J. Fudge's poke in the eye of the anthropogenic global warming controversy.
Right, because no one would say, this [slashdot.org] or this [slashdot.org] which were both modded up. The news article is pretty bad, because Vince Stricherz confuses ice age with glacial. The Nature article is about the end of the last glacial [wikipedia.org] period, not the end of the last ice age. We're still in the last ice age, so the subject line is obviously stupid.
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Please, before you post anything on this topic, go to this site [skepticalscience.com] and check if it hasn't been debunked. By endlessly repeating long [skepticalscience.com]-discredited [skepticalscience.com] views, you're only adding noise to the discussion.
Re:Before anyone drags climate change into it.. (Score:4, Informative)
What's really funny is all the people who say we're in a cooling trend lately when the warmest year on record was 2010. All I can say is enjoy it while it lasts, I doubt you'll still be able to say that in 2020. The greenhouse effect is still in effect.
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There was a Russian scientist who took that bet in 2000 and won. Are we there again? Can I bet you $1000 and win?
The charts are showing me a 0.8C movement since 1900, which doesn't seem to be correlated to anything interesting. CO2 levels are strange--I'd like to see a chart of industrial CO2 output and the INTEGRAL of CO2 output (i.e. total CO2 output since baseline), because warming would tend to make CO2 less soluble and thus CO2 would emit from the oceans (or dissolve less). That means that CO2 out
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Uh, not to quibble, but Fahrenheit is no more "arbitrary shite" than Celsius. The Fahrenheit zero is the freezing point of salt water vs the freezing point of fresh water for Celsius. The 100 point for Fahrenheit was supposed to be human body temperature. As it turns out, his thermometers weren't very good, so he got that end slightly wrong. 98.6 was supposed to be 100. Admittedly, "normal" human body temperature varies quite a bit more than Fahrenheit knew, so as a choice of where to peg his scale, it
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Salt water, wonderful! How much salt in the water?!
It's more complicated than that, and it's based on a scale that's rather arbitrary with water boiling at 60 degrees. Farenheit multiplied all the numbers by 4 and recalibrated.
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As I recall, sea water, specifically. The people who cared the most about the low end of the temperature scale at the time were mariners. When the ocean would start to freeze was important to them.
Also not a very good choice for pegging a scale, but what do you want. It was a long time ago.
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:) Yeah, I forgot about that factor, didn't I.
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Ah yes, the requisite recitation of faith.
And the rest of this is horribly confused. They talk about 'orbit' when they mean 'rotation' (as in around the poles, not around the sun) and they keep talking about an ice age when they are referring to an individual glaciation.
Interesting to see a detectable shift. (Score:1)
I'm not surprised that they happen over time. Has anyone detected a solidly provable shift in modern times?
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"Solidly provable" isn't a definable term. If you want hard evidence, set hard criteria. Should you do so, I think people might be able to comply.
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The thing is, I don't actually care that much. I'll leave the specifics up to the people in that field.
Earth's balance off because of too many people? (Score:4, Funny)
Maybe the earth's orbit changes right now are because there are too many people living in one area and they are weighing down the earth like a seesaw? Like if too man people live on one side of an island the island tips over?
http://www.youtube.com/watch?v=cesSRfXqS1Q [youtube.com]
Are they confused? (Score:1)
Do they mean orbit (around the Sun) or revolution (around the Earth's axis)? I know the Earth's revolution has changed quite a bit in the past, but I thought the orbit was pretty stable. The use of the term "wobble" also leads me to believe they are talking about the revolution of the Earth, and not it's orbit.
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They also talk about the wobble changing the amount of solar radiation incident on higher latitudes which also implies that they were really talking about the inclination of the axis of rotation, not changes in the orbit. Never heard of orbit wobble but it's well known that the Earth "wobbles" somewhat in a way that changes the inclination of the axis of rotation.
Cheers,
Dave
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Both the revolution of the Earth and its orbit around the Sun change over time. The changes in the orbit are driven by interactions with the gravitational fields of other objects in the solar system, primarily Jupiter and Saturn.
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The very minor orbital perturbations balance out in practical terms
Depending, of course, on your definition of "practical terms". One of our hemispheres has significantly more water than the other, which I suspect would be particularly important to anybody studying how climate changes over thousands or millions or years.
However, if "practical terms" means "with regard to global warming", then yeah, planetary wobble it's pretty far from being the prime suspect here.
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Don't forget that as the orbit gets more eccentric it shortens the time spent near perihelion and lengthens the time near aphelion. Also the relationship between insolation and distance from the Sun isn't 1 to 1. To quote the eccentricity section of the Milankovitch Cycles article on Wikipedia:
For the current orbital eccentricity this amounts to a variation in incoming solar radiation of about 6.8%, while the current difference between perihelion and aphelion is only 3.4% (5.1 million km).
The cycle of glaciations for the past million years appears to follow the 100,000 year beat cycle of eccentricity most closely.
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Do they mean orbit (around the Sun) or revolution (around the Earth's axis)? I know the Earth's revolution has changed quite a bit in the past, but I thought the orbit was pretty stable. The use of the term "wobble" also leads me to believe they are talking about the revolution of the Earth, and not it's orbit.
Trying to decipher what was happening in both the summary and the article was difficult for myself. The lack of clarity seems to be due to the article's informal explanation; their not being concerned about the accepted definitions of the terms they were using. I don't know if it was laziness or confusion on their part or my understanding about present day astronomy.
The original article in Nature probably does a better job.
Although I haven't seen the Nature article (due to the payed wall), I suspect it
it's too damn hot (Score:2)
I tell you Krypton is merely shifting its orbit (Score:3)
Relax, Jor-El.
I thought (Score:2)
I thought the last ice age was in the northern hemisphere,(Europe, North America) not Antarctica.
Well you know what that means. (Score:1)
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Dream on.
On the ropes (Score:2)
It's telling that proponents of that failed AGW religion are all posting AC these days...
Talk about needing to get some intellectual order! On the other hand, if all you have is emotion and no intellect, it's hard to order anything except another glass of whine.
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Play the ball, not the man.
What is your argument?
Waaah, he won't tell me the nickname he uses to hide his real name, AGW is a scam and Al Gore is fat.
Can't see a lot of intellect there.
So, do you agree with Stumbles that:
This whole global warming because of mans activities just took a hard nose dive into concrete.
and what in this article makes you think that?
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You haven't been keeping up - they are way beyond that.
Often in the same sentences where they'll criticize AGW-proponents for being overly alarmists, they'll then warn that we really need to worry about global cooling which may have already begun and will wipe out food crops and poor people will die.
Author is so full of it his eyes are brown... (Score:5, Interesting)
There are so many blatant errors in just this one sentence that it's publication is astounding. First, the Earth is currently in the middle of its 5th "ice age," the "Pliocene-Quaternary glaciation," (which began 2.5 million years ago) and what the article calls 'ice ages' are termed by real scientists to be "glacial periods" within the current ice age. The Earth is presently in what is called an "interglacial period" and the next "glacial period" is likely to begin within the next 1,000 to 2,000 years. Next, there is certainly no consensus that either the Earth's "Ice Ages" or "Glacial Periods" are caused by wobbling of the planet's orbit. General consensus by scientists is that both ice ages and glacial periods within those are caused by a variety of factors including atmospheric changes, solar changes, changes in the position of tectonic plates which affect ocean circulation, variations in the Earth's orbit (which are currently considered more likely to affect glacial and interglacial cycles rather than to initiate or end ice ages), and volcanism. In short, TFA is utter bullshit.
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Oh please.
First off, there is a general sense and a scientific sense definitions. The world has less methane and CO2 then when the dinosaurs were around and the atmosphere was thicker so of course the world is much colder.
We wont ever leave the scientific definition of an ice age until the sun expands as a result.
In a general sense we are out of an ice age. In the real world only scientist use such definitions as glaciation only happens in a few spots in the world today. Ice only happens in the winter typic
Crust displacement vs. orbital wobble (Score:2)
I believe Hapgood's crust-displacement theory explains the climate change at the turn of the ice age better than orbital wobble.
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Long answer: Yes, with a "but".
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Short answer: No, with an "if".
Long answer: Yes, with a "but".
Which equals - No answer at all................
Clearly we need to spend a few trillion more to find out the answer.
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Short answer: No, with an "if".
Long answer: Yes, with a "but".
Which equals - No answer at all................
Clearly we need to spend a few trillion more to find out the answer.
No, not at all. It would only cost a few tens of millions to keep "studying" the problem until everyone agrees it's too late to do anything about it. Either of the Koch brothers could just write a check. And in 100 years their descendants will still be rich enough to live on the new coastlines... wherever they wind up.
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And in 100 years their descendants will still be rich enough to live on the new coastlines... wherever they wind up.
That assumes there is enough civilization left that they're not just scrabbling to survive like everybody else.
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Re:So basically... (Score:4, Insightful)
No, it's pretty much just "no". The phrase "global warming" conventionally describes the unprecedentedly rapid rise in temperatures since the industrial revolution. That is entirely "our fault" because of aforementioned unprecedented rate, and that data is quite incontestable without dramatic misrepresentation of what is being compared.
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Well, kind of. A change in orbit caused this before; but that's not what's happening now. What's happening now is sunspots, hence why we've been peaking over the U curve for the past decade (no real warming trend for 15 years!) and in the past 4 years it's been getting colder: sunspots are responsible for global cooling and global dimming (yes, those are real things; yes, I'm talking about a different global cooling than the 1970s ass-on-head clownshoes stupidity).
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Global warming is not our fault.
Why do several people repeat this here? Is it an attempt at sarcasm? Trolling? Does anything remotely related to AGV turn stupid up to 11 in some people? Are some people just inherently lik that?
Hint: Similar phenomenon, such as different changes in global climate, can happen for different, unrelated reasons.
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We can actually tell when this happens, you know. We can examine the soil layers around the earth, and a consistent layer across the whole planet in the same strata identifies a time when substantial dust was settling. I'm pretty sure that's not the case here, but haven't actually looked at what experts say.