Posted on 01/25/2007 4:40:59 PM PST by blam
Sun's fickle heart may leave us cold
25 January 2007
From New Scientist Print Edition.Stuart Clark
There's a dimmer switch inside the sun that causes its brightness to rise and fall on timescales of around 100,000 years - exactly the same period as between ice ages on Earth. So says a physicist who has created a computer model of our star's core.
Robert Ehrlich of George Mason University in Fairfax, Virginia, modelled the effect of temperature fluctuations in the sun's interior. According to the standard view, the temperature of the sun's core is held constant by the opposing pressures of gravity and nuclear fusion. However, Ehrlich believed that slight variations should be possible.
He took as his starting point the work of Attila Grandpierre of the Konkoly Observatory of the Hungarian Academy of Sciences. In 2005, Grandpierre and a collaborator, Gábor Ágoston, calculated that magnetic fields in the sun's core could produce small instabilities in the solar plasma. These instabilities would induce localised oscillations in temperature.
Ehrlich's model shows that whilst most of these oscillations cancel each other out, some reinforce one another and become long-lived temperature variations. The favoured frequencies allow the sun's core temperature to oscillate around its average temperature of 13.6 million kelvin in cycles lasting either 100,000 or 41,000 years. Ehrlich says that random interactions within the sun's magnetic field could flip the fluctuations from one cycle length to the other.
These two timescales are instantly recognisable to anyone familiar with Earth's ice ages: for the past million years, ice ages have occurred roughly every 100,000 years. Before that, they occurred roughly every 41,000 years.
Most scientists believe that the ice ages are the result of subtle changes in Earth's orbit, known as the Milankovitch cycles.
(Excerpt) Read more at environment.newscientist.com ...
Time to toss global warming on the trash heap and worry about the new ice age...Again.
Let me be the first....it'll be Bush's fault eventually, just to discredit Algore's global warming fanaticism. The lengths W will go to!
< / sarcasm>
So where are we in the cycle?
The guy"s name is Grandpierre. Big Peter?
GMU is my Alma Mater - it is where I learned to write computer simulations.
I guess we'd better get going on warming up that earth then!
There's no time to lose!
That's Attila Big Peter to you.
We're still coming out of the last Ice Age...some are calling it Global Warming.
My immediate world-threat list looks totally different.
I did my part today.
I drove my F250 Four Wheel Drive pickup truck with Triton 5.4 Liter V-8.
A 4200 pound gas guzzling behemoth.
Just doing my part to support global warming.
If Algore wins an Oscar, let's all burn some old tires to celebrate!!
...and ask a few of your liberal friends if they would like to participate! LOL!!
Holocene Interglacial Period? The last ice age ended about 10,000 years ago. So according to this theory we should stay warm a while longer.
Attila Big Peter. Good name.
It's entirely feasible to embrace both if we but put our minds to the task.
He's wrong. It's cow farts all the way.
Embracing both sides of a para a doc's will get you in a lawsuit.
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