Here is an eye-opening video from Dr. Naomi Oreskes of the University of California at San Diego. As you may or may not recall, it was Dr. Oreskes who surveyed 928 papers on climate change published in the major scientific journals between 1993 and 2003 and found that 75% of the papers published during that time either implicitly or explicitly accepted the consensus view that mankind was contributing to global warming. 25% held no opinion, and none held an opposing view. Her results were published in the journal Science in December 2004.
Here Dr. Oreskes discusses the origination and tactics of those opposing the consensus view in the mass media.