donald said:
No-one has even attempted to address that. Why?
I pointed you to an IPCC discussion on the issue. What more do you want? I might have done some searches for papers discussing this, after that discussion, as there have been several... and not confirming the effect BTW. But then you would jump to some other talking point? It might be nice to go in depth on one aspect.
And frankly, it doesn't matter. Solar variation might affect climate in an indirect way. So? Solar variation does not explain climate change on very long time periods, and can not explain large climate changes on short time periods.
I've followed global warming in the scientific press since about 1974 so this is familiar topics for me, however I'm not a real expert.
But let us lay out a case for caring about climate change:
1) Doubling CO2 will warm the climate by about 3C +- 1C
a) Paleoclimate: Many comparisons of past climate and CO2 levels. One, just for fun, was climate change even faster than what humans are doing:
http://www.pnas.org/content/99/12/7836.full" onclick="window.open(this.href);return false;
b) Physics based climate models
2) Fossil fuel is abundant, enough coal, near coal, black shales, oil shales, natural gas, tar sands and oil to double CO2 at least 3 times, probably 4 times and perhaps close to 5 times.
a) This is looking at resource estimates, not reserves. The difference is that resource estimates are trying to work out how much is there. A reserve is (err.. should be) fully located, explored, and recoverable at market price using current technology.
b) Looking at reserves, there is about enough to double CO2 about 2 times.
3) Climate change will have winners and losers.
a) "tiny sized" climate change, 0.3 C, might be caused by all sorts of things, net effect is near zero. Normal background 'noise'.
b) "small sized" climate change, 1C, hard to say if net is gain or loss, however net effect is fairly small
c) "medium sized" climate change, 3 C, significant negative, net effect depends on how fast as well
d) "large sized" climate change, 10 C, disaster. Many areas of the tropics are too hot to be livable.
e) "super sized jumbo sized" climate change, 15 C, catastrophic.
At best case, we burn through only the reserves, climate change is 'only' 4 C, a significantly degraded world. Middle case, we double CO2 three times, climate change at 9 C only slightly larger than wiped out the dinosaurs, however, starting in a hotter world. Worst case, super sized jumbo climate change... "Say goodnight, Gracie"
Note as well that there are significant time delays in the system. From deciding to reduce reduce carbon emissions the half emission point is at least decades. From release of carbon to full climate change is multiple centuries.