IMHO, it's blatantly a PR campaign to get the masses to distrust all scientists reporting on the current biosphere situation. Do you think NASA is lying about their reports too? Perhaps not you, but you must admit most people don't go beyond reading headlines.

Don't get me wrong, I think Al Gore is a terrible messenger with more show than content and probably risks making more harm than good (just like celebrities.)

And regarding climate science as just reading temperatures over time is at least overly reductionist. The melting of the Arctic probably counter-balances greenhouse-gases, and there are studies about a short ice-age caused by the melting of Greenland's ice sheet. It's much more complex than what the mass media wants to report on their headlines.

And climate science studies, among other things, the impact of pollution on the atmosphere. Are you serious?