Ice Ages Blamed on Tilted Earth..posted: 30 March 2005

[IGBT]

Text

The Earth?s rotation axis is not perpendicular to the plane in which it orbits the Sun. It's offset by 23.5 degrees. This tilt, or obliquity, explains why we have seasons and why places above the Arctic Circle have 24-hour darkness in winter and constant sunlight in the summer.

But the angle is not constant ? it is currently decreasing from a maximum of 24 degrees towards a minimum of 22.5 degrees. This variation goes in a 40,000-year cycle.


In the past million years, the Earth experienced a major ice age about every 100,000 years. Scientists have several theories to explain this glacial cycle, but new research suggests the primary driving force is all in how the planet leans.



"The apparent reason for this is that the annual average sunlight in the higher latitudes is greater when the tilt is at maximum," Huybers told LiveScience in a telephone interview.

More sunlight seasonally hitting polar regions would help to melt the ice sheets. This tilt effect seems to explain why ice ages came more quickly ? every 40,000 years, just like the tilt variations -- between two and one million years ago.

 

[Torched]

So, in other words global warming is a farce and cannot be stopped.

 

[Vegitto]

Every 100,000 years? So fuc[/i]king what? I'll be long dead by then.

 

[Witling]

Bless you IGBT for citing the article. There are actually a number of theories, Give it a moment's thought! Orbital tilt may not be a good one. There have been whole epochs without ice ages. Did the earth's orbital patterns suddenly change enough to bring on ice ages? I don't think there's much evidence for that but, consider a disturbance in the equilibrium brought about by the impact of the meteor thought to have ended the age of dinasaurs. Or, think about the rise of the Hindu Kush (the mountain range with Mt. Everest). Or, think about . . . Well, you get the picture. Orbital mechanics are a very stable phenomonum as far as I know. Many cycles of differing periodicity. This can lead to cycles "adding effect," but ice ages are a recent phenomonum as far as I know.

 

[IGBT]

Text

The 2004 Indonesian Earthquake and Earth's Rotation


Steven Dutch, Natural and Applied Sciences, University of Wisconsin - Green Bay

Since the great 2004 Indonesian earthquake I have gotten numerous inquiries about whether the earthquake affected the earth's axis.

What was affected was the so-called Chandler Wobble. Objects that are not perfectly spherical do not rotate around a single axis. That's just the laws of physics. I did the math in graduate school. Unless you know tensors, you don't want to go there. Anyway, the earth doesn't rotate smoothly around its axis, instead, the poles wander in rough circles about 10 meters in diameter. Another way to say it is your latitude changes a bit (0.7 seconds of arc) over a cycle of about a year. Anything that redistributes mass on the earth, even weather systems and the circulation of the oceans, can affect this wobble detectably. Think of a bunch of people on a merry-go-round all running over to one side. Since we can routinely locate ourselves nowadays to accuracies of meters, and precise surveys can locate points to millimeters, we can detect even these tiny changes. What happened here was a big chunk of the northern Indian Ocean lurched northward 10-20 meters relative to Asia. It also descended several meters into the mantle, and compressed and elevated northern Sumatra by several meters. It also likely triggered big submarine landslides that caused the tsunamis. So a fair amount of mass got redistributed. The U.S. Naval Observatory tracks this stuff and will tell you all you want to know about it, but I haven't see anything posted about the big quake yet. However, the US Geological Survey posted this:

Question: What effect did this earthquake have on the rotation of the earth? Answer: Richard Gross at JPL has modeled the coseismic effect on the Earth's rotation of the December 26 earthquake in Indonesia by using the PREM model for the elastic properties of the Earth and the Harvard centroid-moment tensor solution for the source properties of the earthquake. The result is:

change in length of day: -2.676 microseconds
polar motion excitation X : -0.670 milliarcseconds
polar motion excitation Y: 0.475 milliarcseconds
Since the length of the day can be measured with an accuracy of about 20 microseconds, this model predicts that the change in the length-of-day caused by the earthquake is much too small to be observed. And, since the location of the earthquake was near the equator, this model predicts that the change in polar motion excitation is also rather small, being about 0.82 milliarcsecond in amplitude. Such a small change in polar motion excitation will also be difficult to detect.

 

[Muerta de Poly]

I think there are a number of factors regarding ice-ages and periods of warmth (a good site documenting recent "ice-ages" vs. past ones is available at http://www.ncdc.noaa.gov/paleo/globalwarming/paleobefore.html). There are quite a few ideas on why this is. Some of the more interesting ones that I've heard about are the fluctuations in the Solar Constant (amount of energy emitted by the sun that reaches the earth; this isn't actually a constant), and eruptions of "super-volcanoes" that have inhibited incoming solar flux from reaching the earth's surface. I'd say that it is probable that a combination of events lead to ice-ages; the hard part is distinguishing between a cyclic event (such as earth tilt) and one that is more variable (such as an eruption) that cause the earth to warm or cool either singly or in unison. Once we've found a trend, it becomes much easier to forecast future phenomena.

 

[piddlefoot]

''Bless you IGBT for citing the article. There are actually a number of theories, Give it a moment's thought! Orbital tilt may not be a good one. There have been whole epochs without ice ages. Did the earth's orbital patterns suddenly change enough to bring on ice ages? I don't think there's much evidence for that but, consider a disturbance in the equilibrium brought about by the impact of the meteor thought to have ended the age of dinasaurs. Or, think about the rise of the Hindu Kush (the mountain range with Mt. Everest). Or, think about . . . Well, you get the picture. Orbital mechanics are a very stable phenomonum as far as I know. Many cycles of differing periodicity. This can lead to cycles "adding effect," but ice ages are a recent phenomonum as far as I know.''

spot on, humans are still learning, the greenhouse effect we know is real from science and chemistry to be true, to what amount we dont ,to what amount humans effected it , we dont truelly know, we do know our pollution IS having an effect on our planet, we dont know how much, its such a complex system , and so massive, our enviroment ranges all the way to our SUN . Thats a big picture and eco system to try and predict, i think we may be a long way from that yet.....

 

[sflahavin]

You seem to forget that we probably haven't had an ice age since about 100,000 years ago... the counter doesn't start at zero with you... Its time for a climate change!

 

[xTYBALTx]

I want woolly mammoths!

Wasn't there an ice age just 10,000 years ago?

 

[The Pentium Guy]

So even if we were to predict an ice age, what could we do about it?
Alter the earth's rotation? How? Nuking ourselves to do this would be a bad option, but in the face of perilous danger it seems like a good choice. Wars, destruction, etc would stop and we'd all unite to solve this problem (and shortly afterwards, wars would resume again).

 

[IGBT]

I want woolly mammoths!

..would they make good pets??..we could shear them and make mammoth sox and sweaters..and golf club mittens.

 

[the splat in the hat]

MMM MAMMOTH MOCKYS...







slippers

 

[DarkSpeed]

I think the point of it all is that its starting to be noticed that our world is undergoing another BIG change. I mean how many of you have noticed that the seasons have started to change over the years. eg: summer becoming winter, ect ect ect..

Even tho this has been happening for years now, I find it funny that everyone has only just noticed or cared about whats going on. The problem is that, there ain't a hell of alot we can do about it, even with all our tech and research.. I rekon something HUGE will happen before will at a level where we can just piss off to another planet in such of a event of taken place...

Just my thoughts..

 

[reverend boltron]

That is an interesting article. The more interesting thing is that in Uriel's Machine, they talk about the ice ages and such, and they say that the last ice age hasn't ended yet. Which is a reason behind the continued rate of rising temperatures now. Where some people think it is global warming, it is very very possible that it could just be that the last ice age is still ending.

This would prove to make some sense considering how freaked out people got about the holes in the atmosphere being caused by cfc's and other pollution that man creates. When a valcano erupts it releases 10,000 times the amount of cfc's that man has ever produced. That is over the course of human existence ya know. Which goes to show that the air pollution we created doesn't really affect the atmosphere as much as we were told.

Granted the area's that are heavily polluted are definitely different than places which aren't. Major cities for example are filthy but rural area's are quite nice. This being the concentration of the pollution in those areas. But when you look at the world as a whole, including all of the space in the oceans and over third world countries where air pollution isn't that intense (or even first world countries where it isn't that bad either), the amount of pollution that has been created in the high-production zones gets pretty much cancelled out over all.

Obviously I'm not saying that pollution doesn't matter, because I personally hate it. I can't stand to see people burning foam or plastics, or throwing litter on the ground, or dumping waste or anything else which is a no-no.

 

[reverend boltron]

Originally posted by: The Pentium Guy
So even if we were to predict an ice age, what could we do about it?
Alter the earth's rotation? How? Nuking ourselves to do this would be a bad option, but in the face of perilous danger it seems like a good choice. Wars, destruction, etc would stop and we'd all unite to solve this problem (and shortly afterwards, wars would resume again).

Nuking ourselves??? Are you serious? Man, that would be a terrible option.

Entering an ice age would be a gradual change and I really think that people (and animals) would adapt. People would move inland towards the equator, and developments geared towards heat conservation would be made. But I really really doubt that we nuke ourselves and give cancer and death to countless people. If we nuked the oceans that would be awful too, because that would contaminate the beginning of the food chain, successfully killing off the rest of us in the long run. Not only by killing of the base of the food chain, but by having toxic food at the start of the food chain.

I honestly think that if we entered another ice age we would be well prepared to enter it. I know that it seems like it would be really cold, but with a gradual increase I really honestly think we would be okay. Look at people who live in Alaska. They have been conditioned to live in those conditions and they can survive just fine. And also people who live in India. It is extremely hot over there. If someone were to go there straight from America or Europe, they would not be in for a good time. They would be severely dehydrated and probably spend a lot of time in the bathroom. But for someone who has lived there their whole life it isn't that much of a big deal.

 

[Future Shock]

There is considerable fossil evidence, notably on plant growth, ice cores, etc., that indicate that the world now is considerably warmer than it has been for a while. That a REAL ice age, even a minor one as has happened recently, would indeed kill off much of the vegetation in the US and Europe, and would severly impact the ability of humans to survive. That they last for tens of thousands of years.

Humans are hardy however, we have survived a few of them. What genetic studies have indicated however is that our population has drastically dwidled during these periods, and estimates are that the last ice age left just a few thousand humans alive - which is why we are genetically so much alike as a race.

We know from diggings and fossil records that many more humans existed at earlier times, including sites that had large populations building stone tools from rocks they must have quarried 10 kilometers away (i.e., they had some social structure and organization to WANT to move that rock and set up an tool-making site far from the rock itself). But these samples date from before the last ice age...so a lot of us must have perished to only have a few thousand left.

While humans may survive, the real question is whether civilization can. Civilization requires infrastructure, and a food supply that exceeds what is needed for day to day survival of the hunter/gatherers themselves (to support artisians, toolmakers, etc.). Hard to believe that we could keep our civilization, unless we had time to prepare a great deal, or had harnessed safe fusion power.

Future Shock

 

[Minotar]

Originally posted by: xTYBALTx
I want woolly mammoths!

Wasn't there an ice age just 10,000 years ago?

You are right! There have been several Ice Ages in the last 100,000. The most recent was roughly 10,000 years ago. The seemed to be only focusing on the major ones, however. Like some have said on this post, even small geological and cosmic events can have noticeable affects on the weather cycles of our planet. The Earth is constantly changing, for numerous reasons. The tilt of the Earth could very well be a player in all of this, among a thousand other factors. I just don't think it is the only thing to consider.

 

[Gibsons]

Originally posted by: Future Shock
While humans may survive, the real question is whether civilization can. Civilization requires infrastructure, and a food supply that exceeds what is needed for day to day survival of the hunter/gatherers themselves (to support artisians, toolmakers, etc.). Hard to believe that we could keep our civilization, unless we had time to prepare a great deal, or had harnessed safe fusion power.

Future Shock

Humans surviving a moder ice age is an interesting question. It gets real problematic if you consider the ice age could last for thousands years. My initial reaction was, you build something close to a Bio-Dome. Use a nuclear reactor for power, it could provide warmth as well as a gimormous greenhouse for food, maybe enough for a large enough population (Whatver that size might be. You'll need very strict regulation of population size in any case).

But what happens in year 300, when a pipe or two (or fifty) breaks? Are you going to have trained welders and nuclear engineers ready to fix it? Will you even have a new pipe to replace the old one, or an acetylene torch? Can you possibly stockpile enough Uranium to last for 1,000 years? It's not likely you can go out and get more when the nearest mine is 200 miles away and covered with a glacier 500 feet deep.

 

[TheoPetro]

Originally posted by: Gibsons

Originally posted by: Future Shock
While humans may survive, the real question is whether civilization can. Civilization requires infrastructure, and a food supply that exceeds what is needed for day to day survival of the hunter/gatherers themselves (to support artisians, toolmakers, etc.). Hard to believe that we could keep our civilization, unless we had time to prepare a great deal, or had harnessed safe fusion power.

Future Shock

Humans surviving a moder ice age is an interesting question. It gets real problematic if you consider the ice age could last for thousands years. My initial reaction was, you build something close to a Bio-Dome. Use a nuclear reactor for power, it could provide warmth as well as a gimormous greenhouse for food, maybe enough for a large enough population (Whatver that size might be. You'll need very strict regulation of population size in any case).

But what happens in year 300, when a pipe or two (or fifty) breaks? Are you going to have trained welders and nuclear engineers ready to fix it? Will you even have a new pipe to replace the old one, or an acetylene torch? Can you possibly stockpile enough Uranium to last for 1,000 years? It's not likely you can go out and get more when the nearest mine is 200 miles away and covered with a glacier 500 feet deep.

these problems are solved by simply encasing every land mass in an impenetrable bubble

*except the ones that the all powerfull america doesnt like ofcourse

 

[Future Shock]

Originally posted by: Gibsons

Originally posted by: Future Shock
While humans may survive, the real question is whether civilization can. Civilization requires infrastructure, and a food supply that exceeds what is needed for day to day survival of the hunter/gatherers themselves (to support artisians, toolmakers, etc.). Hard to believe that we could keep our civilization, unless we had time to prepare a great deal, or had harnessed safe fusion power.

Future Shock

Humans surviving a moder ice age is an interesting question. It gets real problematic if you consider the ice age could last for thousands years. My initial reaction was, you build something close to a Bio-Dome. Use a nuclear reactor for power, it could provide warmth as well as a gimormous greenhouse for food, maybe enough for a large enough population (Whatver that size might be. You'll need very strict regulation of population size in any case).

But what happens in year 300, when a pipe or two (or fifty) breaks? Are you going to have trained welders and nuclear engineers ready to fix it? Will you even have a new pipe to replace the old one, or an acetylene torch? Can you possibly stockpile enough Uranium to last for 1,000 years? It's not likely you can go out and get more when the nearest mine is 200 miles away and covered with a glacier 500 feet deep.

You can't make it with fission power - you would have no place in a closed environment to dispose of the radioactive wastes. You need fusion, which generates orders of magnitude less radioactive waste than fission.

Of course, the current cost of the war in Iraq greatly exceeds in one year EVERYTHING that has ever been spent on fusion research...so we are still some ways away, probably a century or so...

Future Shock