Airplanes are not "insanely efficient" when it comes to greenhouse gasses. A plane emits roughly the same amount of greenhouse gasses per mile per person as a car. Maybe 50% if we assume an efficient plane and an inefficient car. And the number of miles travelled by plane is typically much more. Even one round trip flight from SF to europe is 10,000 miles, which is comparable to a year's worth of driving for one person.
> roughly the same amount of greenhouse gasses per mile per person as a car
I see. How much non-human cargo are these cars carrying? More to the point: how else do you propose one go from SF to Europe?
Reading between the lines, you're either suggesting people stay home or that they take a boat, both of which are absolute crazy talk.
EDIT: moreover, wikipedia's numbers suggest jetliners get roughly 70 to 110 passenger-miles/gallon (https://en.wikipedia.org/wiki/Energy_efficiency_in_transport...). I have yet to come across a car that gets that kind of mileage period, let alone per passenger.
Besides, gas turbine engines are pretty much the model of efficiency when it comes to hydrocarbon-consuming engines. I don't know where you people are getting your numbers but my BS detector is off the charts.
(That's for shaft engines, which a turbojet isn't, but the turboprop examples are jet engines with a gearbox and propellor mounted.) Jet engines are incredibly powerful (per unit of mass) and reliable, but I don't think they're incredibly efficient.
Perhaps I don't understand the measure (entirely possible!) but I think thrust-specific fuel consumption is a better indicator here. You need to account for the thrust required in these behemoths: replace the gas turbine engines with piston engines large enough to produce equivalent thrust and I doubt you'll retain the fuel economy.
Either way, this is an auxiliary point: the per-passenger fuel economy of airplanes is significantly higher than that of cars.
Are you referring to Sivak's report[1]? The problem there is that it compares average trips and not trips where car vs plane is actually an option, according to the ThinkProgress article [2].
I have not read the report itself and I don't know how credible ThinkProgress is. The Yale Climate Connection article [3] points out similar issues. Bottom line seems to be that flying is better than driving alone, but as soon as you have more than one passenger, the car looks more attractive (still depending on the efficiency of the car).
Interesting though that the train is not looking so good in the statistics in these articles. My hunch here is that the numbers would look very different in Europe.
This is a dangerous meme, it's a complete fantasy...
Cars in the US do about .4 kg of CO2 per mile on average and flights 0.2. There's 2x.
In addition, air travel has a much more damaging effect than the same amount of CO2 emitted on the ground. [1]
There's another 2x-4x.
So you end up getting a 4x-8x bigger warming effect contribution per passenger mile. And since you are going about 10x faster in an aircraft, an hour of air travel is 40x-80x more harmful to the atmosphere than an hour of car travel.
The per hour figure is much more relevant because these people would not get around to emitting nearly as much travel co2 in cars even if they drove them every day for 10 hours. Their 2-day trips would turn into 2 week trips. IOW the vast majority of the trips of "elite flyers" would just not get taken.
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[1] "The IPCC, for example, has estimated that the climate impact of aircraft is two to four times greater than the effect of their carbon dioxide emissions alone."
