We are baffled.
The carbon footprint calculators make no sense to us when it comes to the calculations for Jet travel.
Lets run some numbers.
A Boeing 737 burns 800 gallons of fuel per hour
A gallon of jet fuel weighs just less than 7 pounds
In a five-hour flight that is 4000 gallons of fuel weighing 28,000 pounds
Or 14 tons of jet fuel
The 737 will carry up to 162 passengers. Lets assume 80% capacity or 130 in a typical flight
Here is what does not make sense to us:
That works out to 0.107 tons of fuel per person (about 200 pounds of fuel per person)
Yet according to their Carbon Calculators that same 5-hour flight produces the following TONS of carbon per person:
ZeroFootPrint.com 2.71 Tons p/ person (24 times the weight of the fuel)
CarbonFootPrint.com .496 Tons p/person (2.5 times the weight of the fuel)
Green.yahoo.com 2.0 Tons p/person (20 times the weight of the fuel)
How can this possibly be? Certainly the vast majority of the fuel is converted to energy. How is it possible that the jet fuel produces many more times as much carbon as the weight of the fuel itself? Never mind the question as to why all of these calculators give us such wildly different calculations. Something is wrong here or are we missing something?