Without wading into the philosophical weeds, Karl Popper’s famous principle that a theory, hypothesis, or principle is metaphysical, not scientific if it is not, in some way, falsifiable (i.e., testable), seems to apply here. Whether it’s a Kuhnian paradigm or a substitute religion, the AGW scientists and their popularizers, like the egregious Al Gore, seem to have gotten way ahead of the empirical data, much less any coherent underlying theory. The closet they seem to have gotten is: Datum: the planet has warmed a bit, and datum: we have increased carbon-dioxide emissions which can be “greenhouse gases.” Ergo, the warming is due to carbon emissions.
That’s a hypothesis—though not an easily testable one—but even on the grounds of existing evidence, it’s a pretty weak one. As any scientist worth his salt can tell you, correlation does not equal causation, and the correlation here is much more imprecise than you’d like it to be, if you’d like it to be meaningful—the Medieval Warm Period (when Greenland was, well, green) and the last decade of cooling in the face of accelerating Indian and Chinese emissions are just two very recent instances (geologically speaking) that should have sent these guys back to the drawing board to refine their hypothesis.
What effect does industrial carbon-dioxide emission have? Can we distinguish terragenic (or anthropogenic) causes for global temperature changes, or is the sun’s effect too overwhelmingly dominate? These are interesting questions. We have only weak guesses at our disposal, and the very people who should be able to have made this clear seem to have subordinated the process of discovery to one giant, monomaniacal case of confirmation bias.
[Grammar edited slightly for coherence.]
Don’t ask impertinent questions like that jackass Adept Lu.