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New Ice Age Theory
amigoro writes "Most believe that the ice ages are the result of subtle changes in Earth's orbit, known as the Milankovitch cycles. According to one scientist, that is not the case. Robert Ehrlich of George Mason University in Fairfax, Virginia, has developed a model which hypothesizes a dimmer switch inside the sun that causes its brightness to rise and fall on timescales of around 100,000 or 41,000 years, exactly the same period as between ice ages on Earth. The main problem with Milankovitch cycles is that they can't explain how the ice ages go from 100,000 year cycle to 41,000 year cycle. The cycles predicted by Ehlrich's model line up with the observations."
No one tries the old venerable "Frost Post"
This guy's theories are all wrong. Obviously people are causing the 100,000 - 41,000 year cycles. Someone should take away his meterology license...
The party of stupid and the party of evil get together and do something both stupid and evil, then call it bipartisan.
So the new model is heliocentric instead of geocentric. I thought we made this switch centuries ago.
See, I learned something in all those science experiment classes.
OTOH the check word says the "contrary". Maybe the author should use this system to find the solution.
Could it not be a combination of both Milankovitch cycles and the dimming of the sun?
The opinion you suggest can explain differences between two bodies, but not necessarily with the same body over time. This new theory relates to the output of the sun and how it effects the one body - Earth. I would like to see an investigation of how the temperature of Venus or Mars fluctuates as a result of this cycle. Although that is still a pretty hard study as observations are a little bit restricted to the here and now.
the article doesnt say that, and every ice age so far predates the industrial revolution.... if you read the article that is... you are the one who is the one who is retarded!
bring bak the ponies!!
sophism [sof-iz-uhm] -noun
a specious argument for displaying ingenuity in reasoning or for deceiving someone, e.g. beginning with a conclusion and finding reasons to justify it, regardless of where the evidence points.
shouldn't that be:
that's like writing
THE EARTH IS FLAT!!!! according to some guy somewhere.
instead of
some guy somewhere thinks the earth is flat!!
It doesn't explain the cycles but the ice ages are generally believed to be caused by a shift in the jet stream that was caused by the Himalayan Mountains. The cycle's start parallels the rise of that mountain range cutting into the jet stream and causing the shift. The trigger is still up for debate but the cold air is being caused by the jet stream shifting south.
there's a Home Depot just an a.u. down the road - we should ve able to swap that out with a longer cycle dimmer and all will be well.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
Obviously mans careless use of the environment on earth is the root cause of this heliocentric dimming phenomenon. I call for an immediate halt to deforestation and burning of fossil fuels that initiate the anti-dimming process via subatomic sympathetic astrological particles (SSAP)!!
God was my co-pilot, but then we crashed and I was forced to eat him.
natural global cooling? with scientific backing? this sounds like a global warming denier. he should lose his licence and prosecuted in nuremberg style war crimes courts! quick, someone tell al gore!
The war with islam is a war on the beast
The war on terror is a war for peace
It's a neat idea. Are there any observations to support it? Peter Huybers from MIT just presented an alternative model which explains the 40 ky - 100 ky switch nicely without resorting to solar fluctuations. The basic idea is that you start out with ice ages every 40 ky, but at some point the ice accumulation retards heating, and one or even two thawing cycles get skipped. This gives you longer cold periods and a warm period every 80 ky or 120 ky. If you randomly distribute cycles with these two intervals, you can get a peak at 100 ky (but you can't just superimpose the sine curves with those two frequencies). He suggests that the 100 ky cycle isn't real, and just an effect we see from skipping some thaws. This is supposedly supported by oxygen isotope measurements, but I'm not enough of a geochemist to verify that.
"Could it be..."
Who the hell knows...
From TFA: "In an article appearing in the journal Nature, Ehrlich describes..."
Click the nature link and you end up at NewScientist.
Even if this guy has a viable mechanisim for his "dimmer switch", I can't see that it has any implications for our current climate problems. Wake me up again iff someone finds an abstract.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Milankovitch, Milankovitch, Milankovitch, Milankovitch, Milankovitch, Milankovitch (Drops onto New Jersey Turnpike)
READY.
PRINT ""+-0
I thank God the scientists keep looking for patterns and physics to try to explain what we see in the geologic and solar record & current observations of the sun, as that is the ONLY WAY we will ever have a chance of really knowing what long term cycles are caused by. There may be 50 models and theories, but it will likely be a stew of dozens of researchers that finally get a theory that is solid enough to be verified and called a Proof, or tentative Proof.
Fact is, no one can yet show a proof of why, but we do know that Ice ages occurred dozens of times and when, but we can not yet prove what the underlieing factor is that causes the repetition (excluding the major "accidental" supermassive volcano or mega-asteroid).
That is what true science is for, which is to keep digging, sometimes literally, until you uncover the data and principals that can be independently verified and eventually acknowledged as fact.
But that is not convenient for politicians who want power, and bureaucrats who can manage whole new divisions of government if they get funding to try to act on something with the citizens money, when there is only speculation as to what is going on and to what degree, let alone whether we can actually do anything about it.
"The climate depends more on atmospheric composition than on any variation in the sun or even our proximity to it. That's why venus is hotter than mercury."
That's less "difference in atmospheric composition" and more "has an atmosphere or not."
One competing viewpoint with this theory is that these events were caused by a solar "Clapper" which flipped the sun when bombarded with echoes and reverberations from the big bang. This non-viewpoint is endorsed by non-dimmer switch oriented non-scientists but these non-scientist find it more plausible...in lots of ways.
Nope, it is caused by Suburbans, HMVs and Expeditions. Obviously even the dinosaurs had SUVs - the ice ages prove it.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
if (strpos("shill", $comment[text]))
{
echo "[Post deleted due to:] <i>User being a douchebag.</i>";
$sql_code="delete from comments where commentID = $comment[id]";
sql($sql_code);
}
"The cycles predicted by Ehlrich's model line up with the observations."
Shouldn't this be? The cycles predicted by Ehlrich's model were inferred from observations. Implying that a prediction is lining up with observations is not the same as a prediction that's inferred from observations. And besides, the article is claiming it's an inference based on past observations, not a prediction which has been verified with observations.
The article itself makes no such wild encompassing claim.
Oh! Thanks! Who knew winter is actually caused by Santa's exhuast fumes?
Damn, if we could clean that atomosphere up then we wouldn't need to be bothered by seasonal weather!!!11!one!
I knew all along that slight tilt of the earth couldn't affect the weather!
I saw an episode of "Andromeda" where the system's sun would go out every hundred years or so...life imitates TV? (anyone know which epi it wuz?)
That was CNN covering the Bagdad power grid.
Table-ized A.I.
I don't know that 'sophism' is fair. The Milankovitch cycles don't explain two different period lengths. The actual paper (http://arxiv.org/PS_cache/astro-ph/pdf/0701/07011 17.pdf) suggests a mechanism giving a periodic behaviour in the interior of the sun having multiple period lengths. Unless it was arbitrarily calibrated to give the same cycles as Ice Ages (I concede I couldn't follow all the math), it looks pretty reasonable as a hypothesis. If there's a periodic behaviour on the Earth, and a behaviour inside the Sun with same period lengths, and they coincide, that's worth looking into. (Pity we can't observe the interior of the sun as easily as the Earth's orbit.)
This probably is a precursor for the Second Coming. Unlike the first kid who dropped out of carpentry class, the next kid wants to go to college and he needs to save up.
Engineering is the art of compromise.
But come on. "The cycles predicted by Ehlrich's model line up with the observations." The summary says that like its some type of verification. They line up (duh) because he picked the cycles that way. What a stupid end to the summary.
Fwiw, I like the line of thinking - that the ice ages are an action of the sun rather than the earth, but its entirely unsubstantiated and to go _holy crap_ the model that he crafted to fit historical data fits historical data is fantastically disingenious.
Relax I just want some peanuts.
. . . that damn annoying hum.
It seems that this theory should be fairly testable. If the orbital theory is correct, only Earth should display climate cycles of similar periods. If it's caused by the sun, then the whole inner solar system would be affected. Granted, it would be nearly impossible to see such evidence on Mercury and Venus, but perhaps evidence of some form would be left on Mars. I'm not quite up to speed on my astrogeology, does anyone know if we have any kind of reliable record of the ancient Martian climate?
It's true that Venus is hotter than Mercury (well, I'd believe it anyway). But you can't convince me that Titan is colder than Venus only because of the atmosphere! What if you moved Venus out past Neptune, would it still be as hot?
I think global warming is accepted by those with open minds, but keeping an open mind means looking at other science as well. It's how we got here.
This login name for sale.
Try this on for size:
Picture the Earth in a glacial period. At this time most of the landmass is covered in ice. This prevents nutrients from being eroded and washed into the sea by rivers. This in turn causes phytoplankton populations to decline. As we know, phytoplankton are a major CO2 sink. The small plankton population results in rising CO2 levels, thus increasing temperature.
Melting ensues.
Now picture the Earth in an interglacial period. Most of the landmass is open to the elements. Rivers freely wash nutrients into the sea, and cause phytoplankton populations to boom. The plankton absorb CO2, cooling the Earth.
Freezing ensues...
>> a model which hypothesizes a dimmer switch inside the sun
No, seriously? That must be how they get it to be all dark and stuff at night.
Venus' albedo is 0.65; i.e. it reflects 65% of the light, thus it absorbs 35%. Earth's albedo is about 0.3, the Moon's 0.12. Venus would be even hotter if it was less reflective, but still it absorbs a lot of sunlight.
Most believe that the ice ages are the result of subtle changes in Earth's orbit, known as the Milankovitch cycles.
Whereas I believe that the ice ages are the result of subtle changes in John Malkovich's moods, known as the Malkovich cycles.
Moderator hint: a comment is neither "Flamebait" nor "Troll" if it is true.
It seems to me that a number of Theories in Science (this doesn't include Creationism, since that's only an unsupported Hypothesis, and not actually a Theory) compete with each other as if There Can Only Be One right answer. Often, though, when the dust finally settles, the Truth turns out to consist of elements of more than one of the competitors. So, in this case, I wouldn't be surprised if the Truth about Ice Ages includes both the "dimmer switch" and the orbital mechanics thing.
The sun causes the Ice Age, but doesn't have any significant effect when Global warming is involved, only human can warm the earth... mostly conservitive humans.. :)
Ad eundum quo nemo ante iit!
"Solar Resonant Diffusion Waves as a Driver of Terrestrial Climate Change".
Dear Earth,
Which one of you apes put the sponge in the cosmic microwave?
- God
.....so he can punish us with increasing temperatures.......
These people did not come up with this idea. The Bible has references to severely increasing heat from the sun as part of God's punishments for human evil, reserved for the last days. One of these is found in the Old Testament in Isaiah 30:26, where we are informed that the sun will be seven times hotter and another is found in Revelation 16:8-9. There it says that people will be scorched by the sun and curse God because of the great heat. The passage in Revelation is just before the part about the final battle of the final war, the battle at Armageddon.
To many here, the Bible represents fiction and fairy tales. However, an all out global war and the resulting world wide upheaval, along with havoc from nature is not impossible. We humans like to believe, both corporately and individually that we are the captains of our ship and the masters of our fate. From a sudden death of a loved one, to history of great natural disasters and from the very real possibility of global thermonuclear and other technologically advanced warfare, that belief and hope is ill founded. Global warming, human caused or not, can only add to this nightmare. Could it be that we really are NOT in charge after all?
All theory is gray