National Public Radio: MELISSA BLOCK, HOST:
And let's listen to some voices of climate change skeptics.
(SOUNDBITE OF FILM, "MERCHANTS OF DOUBT")
UNIDENTIFIED MAN #1: Climate is changing naturally.
UNIDENTIFIED MAN #2: It has to do with sunspots, and it has to do with the wobble of the earth.
BLOCK: These are voices from the fossil fuel industry and the industry of advocates who speak for them.
(SOUNDBITE OF FILM, "MERCHANTS OF DOUBT")
UNIDENTIFIED MAN #3: We need more data. The science isn't there...