carbon free? how do you know that nobody emptied a bottle of sparkling water in there?

also, more seriously, does anyone realize that there are greenhouse gasses way more dangerous than carbon dioxyde, like methane?

Methane is bad, but CO2 is more prevelant and lasts longer. Of all greenhouse gases, curbing CO2 should be the number one priority as its effects last much longer.

yeah but it can be misleading, something can have a "low carbon footprint" and still produce a lot of methane or other gases...