I don't think even Al Gore really has a clue. I watched his movie twice as part of my education process.
There were two glaring omissions from the film.
1) No mention of the phrase "Corrolation does not necessarily mean causation." in connection with his temperature and CO2 chart comparison.
2) No mention or explanation of the term "radiative forcing", or what the limitations are of this important concept concerning green house gasses.
No one honestly, objectively, and knowingly explaining global warming could leave these 2 things out.
I read an article lately that said the corrolation shows that changes in temperature occur before changes in CO2 occur. If this is true, I don't see how changes in CO2 can be causing changes in temperature.