Comment Dihydrogen Monoxide Vapor (Score 1) 695
Dihydrogen monoxide vapor is a far more prevalent and effective greenhouse gas than CO2. Though methane is even more powerful, dihydrogen monoxide wins on overwhelming volume.
CO2 is a red herring. Methane is a red herring. We have to get handle on dihydrogen monoxide emissions if we are to have a prayer of halting global climate change.