I think that when thousands of scientists reach a concensus that the climate change that is quite measurably happening is the result of human activity, it is akin to puting one's head in the sand to choose to believe otherwise for monetary gain or idealogical imperative.

I've studied enough physics, chemistry, calculus, chaos theory, and geoscience to read and understand scientific papers. If their research was well designed and their analysis seems sound, I see no reason not to accept their findings. No good scientist will claim to have all the answers, and as new data become available through funding, technology, or new, testable theories, the models for how climate works and how we impact global climate patterns will become clearer, but that will probably always be true. In the meantime good science using what we know now and the data currently available still paint a useful picture, even if not all the details have been filled in yet.