Quote:
Originally Posted by renormalised
One of the reasons why there appears to be no good explanation for the link between sunspot activity and climate is that the answer is staring them in the face. It's this....what happens to the Sun during the sunspot cycle. What happens to the Sun's luminosity when it's active and there is a lot of activity sunspot wise?? It's luminosity increases. What happens to the Earth when the amount of light and heat reaching it increases. It gets hotter. Now, there is lag due to the differences in solar insolation between air, water and land. Plus you have to factor in how the oceans store and carry the heat around, changes in cloud cover, water vapour content in the atmosphere, greenhouse gas concentrations etc etc etc.
So when the Sun is less active, as in during long periods of quiessence like the Maunder Minimum, the reduction of solar insulation at the Earth's surface cause a consequential reduction in heat being input into the climate, hence the Mini Ice Age.
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Without being rude... well yes, no and perhaps...
I strongly recommend you read R.J. Tayler's 1989
Quarterly Journal of the Royal Astronomical Society pdf article entitled "The Sun as a star".
Especially on pg.147,
http://adsabs.harvard.edu/abs/1989QJRAS..30..125T which says;
"The excess radiance from bright faculae at solar maximum is greater than the loss from sunspots." If there were a correlation, it is the bright threads of faculae on the solar surface and not sunspots."
(This is graphically show on pg.148)
It is interesting that the output of the Sun is about 1367 Watts per square metre, whose variance during the solar cycle is no more than about 0.25%. Atmospheric conditions, especially cloud cover, ocean temperatures, etc., would cause far more influence than solar output.
When compared to long term climatic changes, like ice ages, the cause is more due to changes in the tilt of the Earth's axis (obliquity of the ecliptic) that varies roughly between 24.5 to 22 degrees every 50,000 years or so, and even changes in the Earth's distance from the sun or the shape of the orbit.
Whilst probably too detailed for this general thread, I've attached a graphic of the so-called Milankovitch Variation, which shows the historical variation between now and million years ago. (This shows the Earth is peaking at a warmer part of the Earth history.)
You are right in saying "Yes, it is an extremely complicated system..."
