A New Ice Age Theory: Solar Variability

[doubletruncation]

There is a new theory on the cause of long-term cycles in the Earth's temperature (over 100,000 - i.e. not recent global warming). <br />A press release can be seen here: http://pressesc.com/01169672696_ and a preprint of the paper can be seen here: http://xxx.lanl.gov/abs/astro-ph/0701117<br /><br />The prevailing theory has been that these temperature variations are due to secular changes in the Earth's orbit (Milankovitch cycles). However, Robert Ehrlich from George Mason University has demonstrated that the Sun should undergo periodic fluctuations in brightness at periods that match up very nicely to the observed long-term periodicity in the Earth's paleotemperature record. While people have speculated in the past that solar variability may have induced some variations in the Earth's temperature, this is the first time that a specific mechanism has been demonstrated. Moreover, this mechanism does not suffer from a number of problems that have faced the Milankovitch cycles. Namely, that the Milankovitch cycles underpredict the amplitude of the Earth temperature variations (without invoking some ad hoc strong feedback mechanisms), lack of temperature variations with other periods predicted from the Milankovitch cycles, on some occassions the warming on Earth predates the change in insolation from the cycle, the Milankovitch cycles cannot account for the sudden change in periodicity a million years ago. This is not to say that Milankovitch cycles do not occur (the variations in the orbit are very well established) or that they don't have any impact on the climate, just that they may not be the dominant cause of long-term climate variations. Interestingly, the new theory also predicts a new class of variable stars that could in principle be searched for. <div class="Discussion_UserSignature"> </div>

 

[docm]

Funny that while living with a star that varies so much variability and sunspots aren't taken more seriously as regards "climate change". <div class="Discussion_UserSignature"> </div>

 

[3488]

I quite agree.<br /><br />I even think that the current round of 'Global Warming' is sun induced. Rising CO2 & Methane levels will not help, but I still think that man made Global Warming is a myth.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[5billionyearslater]

Look at Venus. Venus is in a run-away greenhouse effect and this is certainly not sun induced.<br /><br />In my opinion, Global Warming is terrestial based, just as in Global Dimming, which in an odd way kinda reduces Global Warming a little.<br /><br />However, I do think the term 'Global Warming' is little miss-understood by the general public, mainly due to the political angle it is usually taken from. It has sort of become commercialised, if you know what I mean, people just say "Oh, it's Global Warming!" without really knowing what global warming is from a scientific point of view.<br /><br />You agree?

 

[silylene old]

<font color="yellow">Look at Venus. Venus is in a run-away greenhouse effect and this is certainly not sun induced. </font><br /><br />Uh, if the sun suddenly went dark, I can guarantee you that Venus' greenhouse effect would cease simultaneously. Venus' greenhouse is 100% sun induced, as it's energy input comes entirely from the sun.<br /><br />I think you meant to say that Venus' dense atmosphere and gas composition creates a condition in which the sun's radiation induces a greenhouse effect by trapping a significant portion of the radiant energy. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[5billionyearslater]

Yes, exactly, which is what the greenhouse effect is.

 

[alkalin]

I think we have found many stars that vary but not many vary in regular cycles. What if these non-rhythmic but varying stars live in regions of space where they can get considerable amounts of fuel at varying times from such things as comets? I feel our sun is somewhat variable due to comets and other bodies entering the sun but the variation due to this is rather sporadic due to remoteness of other nearby matter. Some might argue that there just are not enough comets entering our sun to make any difference, and that probably is correct most of the time. But there may be other occasions where our sun crosses space that can give us a shower now and then. This is not easy to verify perhaps, but in the case of our sun recently, we have seen many comets actually enter the sun. And for every comet seen doing this, there could very well be millions of smaller ones doing the same.<br /><br />There just may be a bias on the part of astronomy to be in denial of the mechanisms for star fuel due to the presently accepted age of the universe, the magical 13.7 billion years. Since it is believed that stars cannot live longer than that, it might encourage the notion that if they do not have outside fuel then they die young, and so I feel there is the effort to find support for some kind of weird theory. I would rather go with the obvious, even if it means many stars are much older than we think.<br />

 

[dragon04]

I think people either fail to grasp or just overtly ignore the fact the sheer scale of energy output by the Sun and the implications of fluctuations.<br /><br />Even a fraction of a percent increase in the energy the sun would deliver to Earth's atmosphere is prodigious relative to us.<br /><br />2.5 billion years ago, the sun was <b>significantly</b> less luminous, yet the fossil record indicates that things were quite temperate at times. That would be a good argument for a greenhouse effect.<br /><br />Over the eons, the Sun progressively has and continues to deliver more and more energy to the Earth. Sunspots have been shown to moderate that energy delivery. Perhaps there were far more "control rods" in the reactor a million years ago.<br /><br />I find it very likely that this is the case. That's not to say that human activity does not exacerbate the warming effect, but I have to wonder if human activity isn't a candle flame in a blast furnace. <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[MeteorWayne]

As I understand it, the sun delivers more energy when there are sunspots. Recall the Maunder minimum when sunspots disappeared for a century it was ver cold hereon planet earth. Satellite measuremants have confirmed this. So rather than moderating, sunspots turn up the burner a bit. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[dragon04]

Guess I had that bass ackwards. Thanks for the info. <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[MeteorWayne]

I know, it's conterintuitive, but true. <img src="/images/icons/cool.gif" /><br /><br />(Sunglasses for the beginning of the next solar cycle)<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[Saiph]

Well, it isn't a new idea that the sun may be a major impactor on global temperatures (there was a major push in the 70's about this). However, this may be the first time they've been able to do a detailed paper on it. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[thermionic]

Ah, so we should start an initiative to reduce sun-spots and normalize the Earth's orbit? That's probably easier than getting people out of their gas guzzlers!<br /><br />On an aside, I overheard a snippet from a radio interview of the guy who advocates the 'Gaia hypothesis', if you're familiar with that. He mentioned that there is a geological record of a volcano naturally igniting an oil basin in the North Sea. Apparently this event correlated with a global temperature spike, putatively caused by the CO2 release from the oil fire. Seems like a nice data point for calibration. Is that a true fact, or the other kind?

 

[R1]

somewhere somebody's post mentioned the possibility of earth going in an ice age as early as in 200<br />years. <br /><br />Would a warming earth be what we want in order to fight a freezing earth? <div class="Discussion_UserSignature"> </div>

 

[docm]

Some work done by the Russian Academy of Science predicts a mini ice age (at the least) by 2055 with cooling being apparent in a few years. Cause: a coming solar minimum.<br /><br />http://www.mosnews.com/news/2006/08/25/globalcooling.shtml <div class="Discussion_UserSignature"> </div>

 

[thalion]

I'd like to see how this theory compares vis-a-vis continental configurations and atmospheric variations over the course of Earth history before I'm sold; in truth, I think there may be no one cause for ice ages applicable to all geologic periods.