Politically and ideologically driven non-climate-scientist Phil Plait suggests that his "classical training in science" leads him to rely on the claims of other scientists, therefore CO2 causes bad weather

Climate Change Deniers Write Another Fact-Free Op-Ed

Of course, I’m not a climatologist either, though I am an astronomer classically trained in science, and that means I know enough to rely on the combined research of actual climate scientists from around the world. And when thousands upon thousands of such scientists— in fact, 98 percent of actual, bona fide climate scientists—say global warming is real, well then, that strikes me as being somewhat more credible than a hundred or so politically and ideologically driven non-climate-scientists.