How does obesity increase climate change?

Recently New Scientist magazine published an article called 'How the obesity epidemic is aggravating global warming' - have you read this? You need to be a subscriber to read it. I've not seen/heard this matter covered in the news, and it sounds pretty crackpot as a concept, so what's the gist of the theory? How is obesity aggravating Global Warming? If this is something valid then what do you think supporters of the CO2 bandwagon will do about it? A CO2 fat tax maybe?