Originally Posted by
ultimattfrisbee
And I should have been more precise. The calculator claims to calculate pounds of greenhouse gases, not carbon, and so that's my misstatement. As for the barrels of oil, what you say makes sense.
In terms of 'carbon' released, it is generally understood that 'carbon' is short hand for carbon dioxide when referring to the burning of hydrocarbon fuels. Since carbon dioxide is the important byproduct of the combustion of hydrocarbon fuels, it is germane to talk about the carbon dioxide released and not just the 'carbon' within that molecule.
Each gallon (US) of gasoline does releases 19.4 lb of carbon dioxide.