This is just "Pascal's Wager" on the existence of (the Christian) God redressed for environmentalism. If you follow the link to the wiki you'll even see the same decision theory style matrix being used.

Given that I regard the "man-made global warming" campaign as a quasi-religion, the use of Pascal's simplistic logic trick seems entirely appropriate. The guy on the video is clearly an evangelist (spread the word!), and his enthusiasm for catastrophy as a consequence of inaction is hilarious.

If you replace "existence of God" or "man-made global warming" as the true-or-false option with something like "stepping on the cracks in the pavement brings bad luck", then the actual worth of this matrix is exposed. The same logic applies, this time to something obviously preposterous. 

Tread carefully, fellow Brycers...  ;-)