warmonger1981 wrote:But has CO2 levels ever risen before the temperature did?
I don't know. I am not aware of that happening any time at the end of the last few ice ages though.
If not then why worry about CO2 levels rising before temperature if its not an adequate indicator for global warming?
The lag doesn't mean that CO2 is not causally connected with global warming. What is going on is that there is some initial temperature increase for some reason
other than a CO2 increase (in the case of the ice ages, the thought is that it was orbital changes causing differences in the Sun's intensity on the Earth). Then this triggers a positive feedback loop because the warmer climate can hold more CO2 in the atmosphere. CO2 definitely has a warming effect on the planet -- there is zero doubt about that, even from the global warming "skeptics." So the release of this CO2 warmed the planet more, and as the climate got warmer it also got able to hold more CO2, resulting in a loop that continues until the planet is able to reach a new equilibrium several degrees Celsius warmer and ending the ice age. On this explanation, the ice ages wouldn't necessarily have been able to warm by nearly as much to the present-day temperature
without this carbon-dioxide temperature feedback.
In this case we are seeing the same pattern: the Earth's climate was essentially in an equilibrium so it didn't have a way to get an initial spike of CO2 into the atmosphere. But now industrial civilization has come along and done just this. So we are expecting to see similar kinds of feedback processes now that we have unleashed that beast.
Why is the sun not included in being a major factor for global warming?
Mainly because the Sun's intensity hasn't markedly increased in the last century or so, in a way that would explain what is going on. It has mattered in the past when explaining the ends of the previous ice ages, but that was because of intensity variations that took place over a longer time scale (and were also likely due to orbital changes, not changes of the Sun's output itself).
Has anyone considered the legitimate ramifications of weather modification currently happening as a factor?
Yes. The most salient fact is that clouds tend to reflect sunlight, and weather patterns will affect how much sunlight reach the surface. And actually this contribution to climate change is basically the most uncertain we have in the near term. But most estimates of cloud processes indicate that the net effect on the climate's temperature is rather small (since there are counter-balancing processes that also trap heat on Earth).