Both the National Academy of Sciences and the IPCC are essentially political organizations (in the sense that their purpose is to inform policy, I don't mean to

Both the National Academy of Sciences and the IPCC are essentially political organizations (in the sense that their purpose is to inform policy, I don't mean to suggest that they are partisan) and what they say should not be conflated with the scientific literature on climate change. Scientists are working very hard to understand past and future climate change, but it is an incredibly complex problem. (For analogy, can political scientists predict who will be elected president in 2012?...it's possible to make some good guesses but there are a lot of factors and it's hard to know what will happen.) Sure, there is general agreement on some points and organizations such as the IPCC are doing a noble job of trying to synthesize the mountains of complex science into a few simple statements, but I think you are drastically oversiplifying the case when you say that "99.99% of the world's scientists, based on careful interpretation of many thousands of peer-reviewed studies, agree that global warming is real, and is caused by human activity. A vanishingly small handful of scientists happen to disagree with this assessment, based mostly upon their opinion and politics."