"aviation will be responsible for most greenhouse emissions" We are very far away from this utopia. Most is coming from electricity production and heating right now.

@Bianfable Nope - transportation tops electricity by 1%: epa.gov/ghgemissions/sources-greenhouse-gas-emissions

That is for the US only. This page says 49% for electricity and heat, only 20% for transport.

@Bianfable Gotcha. Thanks for the clarification.

Does aviation produce more than shipping? Large marine engines can burn 150-250t of oil per day and are probably running for a larger fraction of the time than aircraft engines.

A glider with a winch launch? Not sure how winches generate power.

"... since when automated cars are the only means of ground transport, aviation will be responsible for most greenhouse emissions." - You seem to imply that normal cars are responsible for greenhouse emissions, but automated cars aren't - or much less so. Why do you think there's a difference?

@marcelm I'm guessing electric cars were meant instead of automated ones. As you've noted, automated cars obviously don't use significantly less energy than non-automated ones for the same powerplant. Indeed, they might actually use slightly more in order to power the computers and sensors.

Keep in mind, much of the world uses public transport which is often electric. You know that weird city nobody ever heard of in the theUrals where the meteor hit? Every dash cam showed 2 weird wires over the middle of the street. That meant any random midsize street in any little unknown Russian town has a thick network of Trolley bus tracks. Electric buses.

Thank you, @Harper. I am well aware of the differences between ships and planes and don't need you to lecture me about them. I asked only about the amounts of CO2 produced by aviation and shipping and not about the amount of useful work done while incuring those emissions, since the latter is blindingly obvious. I'm not "missing" anything.

A hang glider is foot launched from the top of a hill but you'll usually have to drive it up there. A paraglider can be carried up on your back

@Bianfable Remember that avgas contains lead, so it is a major source of pollution with that particular toxic heavy metal. Now sure, some single engine props are compatible with unleaded gasoline, but not all of them.

@forest I wasn't talking about pollution, only greenhouse gas emission. But I agree that someone who really cares about the environment should take all emissions into account.

Once you have learnt to fly, what are you planning on doing with the skill? It's hard to see how you can use it without causing more environment impact anyway.

Attend Daedalus's (Δαίδαλος) flight school, but don't become Icarus (Ίκαρος). :)

@Harper I was simply addressing the claim that aviation is the biggest emitter of CO2 after road transport. I was not making any value judgements about aviation versus shipping. I was not attempting to quantify the benefits of aviation versus shipping. Your comment was perfectly clear: your error was to read a whole bunch of stuff that I never said into my comment, and then criticize me for that whole bunch of stuff that I never said. Please stop.

@DavidRicherby I see your point. Sorry to annoy. But meet me halfway and don't take everything so personally lol... it was never a personal attack on you... and I'm not going to be super delicate all the time in case someone happens to be a crybully...

@GaneshSittampalam What’s the point in learning to fly if you’re never going to use it? If you’re concerned about the emissions, then don’t do it in the first place. If they don’t bother you to do it in the long-term, why let it hold you back when learning? Your question is like asking if you it’s more economical to learn to drive a car by riding a bike instead. The answer is obvious but it won’t be the one you want.