Re: @ NomNomNom @ AC
> Popper's philosphy was that to count as scientific, then a _hypothesis_ must be _falsifiable_.
That is a grotesque oversimplification of Popper. What he actually said was that theories must maximize their explanatory power, i.e. being as specific (and therefore falsifiable as possible) and explaining as much as possible of the available evidence. There is no requirement that the theory as a whole must be abandoned the second a contradictory piece of evidence is found: the Copernican heliocentric theory was not perfect and in fact required fudging to fit the data, but was still better than the Ptolemaic system (required less fudging == better explained the evidence == higher explanatory power).
> In this sense (and this sense only) most hypotheses about climate change are not scientific, it is not possible to perform an experiment whose result would falsify the hypothesis
Congratulations, you have just asserted that astronomy, evolution, paleontology, and every other science which cares about past events, is not science at all. After all, I can't re-run the big bang, so cosmology is not science, right?
Wrong. Science is investigation of causation; causal relationships can be inferred even when direct observation is impossible. Your definition of science is blinkered.