This comment was posted to reddit on Apr 02, 2015 at 10:06 pm and was deleted within 16 hour(s) and 57 minutes.

People think they need a citation for everything when really all they need is a calculator, some basic facts that can be googled in 2 seconds, and a brain. There are 100 different ways to do this calculation. So, here's one of the ways done by a friend who is really good with facts and calculators:

1) Standard CO2 level is 285ppm. Today we are at 400 ppmv. That is an excess of 115 ppmv.
2) The atmosphere is 78% N2, 21% O2, 0.93% Ar, and 0.04% CO2 approximately, leaving 0.03% other - by volume. The mass of the atmosphere is 5.15 e18 Kg.
3) The atomic weight of N2 is 28, O2 is 32, Ar is 40, and CO2 is 44. The fractional weight of CO2 is then: 0.04x44/(0.04x44+28x79+32*21+40*0.93) = 6.02e-4, or 0.0602%.
4) The atmospheric mass of CO2 is then 6.02e-4 x 5.15e18 = 3.1e15 Kg.
5) According to the IPCC, CO2 is now causing 1.68 W/msq of forcing. The surface area of the earth is 509 e6 square Km.
6) A gallon of gasoline creates 19.6 pounds (8.91kg) of CO2.
So the total power of one gallon of gas is: 8.91 / 3.1e15 x 1.68 x 509e6 x 1e6 (msq/kmsq) = 2.44 watts.
6) A gallon of gas has a heat energy of 33.7 KWH. So it would take the co2 of one gallon 33.7x3.6e6/2.44 seconds to produce the same heat, or 575 days.
7) But, we need to correct for the excess: 115ppmv vs. 400ppmv, bring it down to 165 days.
8) But we need to also correct for the CO2 that gets absorbed into the ocean and land. About 46% remains in the atmosphere. That bumps the time to 360 days.

So, here my friend estimates, based on this set of facts, that it will take 1 year for gasoline to trap the same amount of energy via global warming that the gasoline produced when it was burned.

As I said in the intro - you can choose your own facts and do your own calculations. If you want citations for each of the facts - like how many pounds of CO2 a gallon of gas makes, then I suggest you cut and paste each fact into google to verify whether it's right or wrong. Or, come up with your own set of facts and your own calculation and see what you get. Using a completely different set of facts and doing the calculation in my head for coal, I got about half that time. Another time, I did essentially the same calculation based on the amount of cow manure that an Indian family burns to cook their food, combined with the kerosene that was used to sinter the bricks that made their house, to extrapolate whether we'd all be better off living like Indians without electricity (the answer is not a lot better because their population density is so high). It's a good rule of thumb: 1 kWh of fossil fuel = 1 MWH of global warming (over 1,000 years).