http://www.youtube.com/watch?v=rb9jTeFcatU

wouldn't the changes in the sun over the years be a cause of global warming.

There was a debate about this not too long ago right here in the U.M. boards, I myself participated... a bit. You can try searching for it.

The Little Ice Age was also the result of solar activity. Sun spots caused a cooling of the Earth starting around 1250 A.D. This ice age lasted until about 1650 A.D. and only around mid-19th century did glaciers begin to retreat. No doubt in my mind that the sun is contributing to global warming, but I don't think it's the only cause. We have contributed to it a lot, but remember, there are forces of nature and space that are at work as well. Volcanic activity and methane leakes are just two things on Earth that can be responsible for global warming. However, I don't know how much of a difference the fact that the Earth is *still* recovering from the Little Ice Age means for global warming, whether it makes the current trend of global warming worse or reduces the effects.

But no, I don't think the Sun is the single cause for global warming.

Yes, Mark...that would, and has definitely been a cause of the repeated cyclical global warming periods this planet had experienced for millions of years.

Actually Roughneck, sun spots are an indicator of increased solar activity.
The general scientific opinion is that the "Little Ice Age" was a combination of decreased solar activity and increased volcanism.
However, there is still debate on the matter.




Volcanic activity (on a very large scale) contributes to a cooling effect due to the blanketing and shielding effect of volcanic ash as pertains to solar radiation, and due to the increased Sulfuric Acid in the upper atmosphere, which is a reflector of solar radiation...

Uh yeah, I meant to say "decreases in sun spots." The Maunder Minimum was coincidentially around the same time of the Little Ice Age. My mistake.



Yes, there was an increase of volcanic activity during this period, as well, including the infamous eruption of Tambora.

Edit: Forgot to add that Volcanic activity may have had a role in ending the global ice age of the Cryogenian period by replenishing CO2 in the atmosphere.

according to the scientific evidence and the "real" scientists out there ... yes most definatly. Not all of the reason, but enough to make those with an agenda look "crazy"

Yea...kinda like that!

Just to make sure everyone knows, the video posted at the start of this thread shows the differences that are a result of the normal 11 year activity cycle of the Sun. Happens over and over with relatively little variation. Something that would cause climate change would need to be a LONG lasting event with a hugely different activity level sustained for a long time - such as, possibly, the Maunder Minimum.

the sun is getting warmer and the safe zone is supposed to be moving away from earth

This is believed to be the case, however this is something that happens over a timescale of billions of years. It's predicted from the fact that as any star burns hydrogen in its core, you get fewer more massive helium nuclei and the core contracts and heats up and gets denser, allowing a faster reaction rate. This, however, is a process that happens very gradually over billions of years and would not be a perceptible cause of global warming.

This is correct. The Sun has various cycle periods, the Sunspot cycle is just one of them.


Tom
(who spent 8 years taken solar sunspot data of the AAVSO.)