Letter: Carbon dioxide emissions

Re: the Oct. 30 article “Carbon facts.” Yes, facts are important, but so is context. Mr. Scholl supports his argument that gasoline is worse than coal by contrasting the CO2 emissions from tons of coal and gallons of gasoline. A ton is a mass unit, whereas a gallon is a volume unit. Without standardizing on a common unit, such as Btus, no meaningful conclusions can be drawn. According to the Energy Information Administration, coal on average produces 211 pounds of CO2 per million Btu, whereas gasoline produces 156 pounds. So, for a comparable amount of energy produced, coal is clearly worse than gasoline with regard to CO2 emissions.