Banning a particular form of transportation seems a poor method for reducing emissions. Just tax the fuel properly and it will sort itself out. Flying is currently much too cheap compared to its environmental impact imho. How can it be cheaper to fly from Berlin to Munich than taking the car (or the train)?

"tax it properly" Define properly.

We are afraid of possible feedback loops destabilizing ice sheets much earlier than predicted? Maybe the price should be 5x what it current is?

If emitting CO2 causes unknown massive harm, then it seems sane to figure out a CO2 neutral method to create these liquid fuels that jets require. That would seem very expensive, with current technology.

Defining "properly" when related to taxes is too difficult for a HN comment. Also, I'm neither a climate scientist nor do I consider myself an expert in economy. I'm rather concerned about climate change, so my numbers would likely be much higher than necessary.

But I'd suggest putting a bunch of scientists in a room for a while to figure out the environmental impact and define some acceptable limit of yearly pollution. Then raise taxes until we're under the limit. Or something similar.

Have them do it every 2 years to account for changing science.

Of course, then you have a de facto regulatory body, which everyone hates, and thus a new problem.

Sounds good to me.

Properly, in this context, simply means tax it like you tax fuel/energy for other modes of transportation.

Airlines have been very successful at getting special treatment by scaremongering "no more connections for you". Which is certainly a mostly empty threat, because connections will only go down by as much as demand elasticity reacts to the price difference.

Difficult to define it, but we can be pretty sure we're nowhere close with our current tax policies.

In theory you set the tax rate to counteract the net negative externalities. It's estimating those externalities that's the source of contention (as you hint at re: feedback loops). So assign ten teams to estimate it and take the median?

I agree that the fuel should be taxed but Concorde flew a lot higher than other commercial jets, this could change the environmental impact.

There were instances of U2s being asked to change course to stay out of the way of a Concorde.

>How can it be cheaper to fly from Berlin to Munich than taking the car (or the train)?

I can't answer that specific case, but in general it's pretty simple, especially if you're comparing cars and planes: when you drive yourself in a car, you're not only transporting yourself and luggage, you're also taking a 3000-pound hunk of steel. On a plane, it's just you and some bags. You can pack a bunch of people and their crap into an aluminum tube when you give them sardine-sized seats. You get big economies of scale when you do things at larger sizes. And with an airplane, you don't have to take windy, indirect routes and stop at stoplights.

With trains, it's not so clear-cut: trains are generally more efficient than road-going vehicles, because they have lower friction (steel on steel rather than rubber on asphalt), less acceleration/deceleration (no stoplights), and economies of scale (lots of people can fit into a train). One possible problem is the tracks don't go the best route, as they have to conform to both local geography and also history, and tracks are expensive to build (airplanes go directly between airports and the only infrastructure they need is the airports, nothing in between).

Google Maps is ridiculously slow where I am so I'm not going to try finding the driving time between Berlin and Munich, but I'm guessing it's around 3-4 hours? Why a plane might be cheaper (I'm taking your word for it) probably comes down to differences in regulation between airlines and trains in Germany. I agree, it shouldn't be that way; trains should generally be cheaper. Here in the US, trains are generally terrible. Amtrak is actually OK in the northeast corridor, but outside that it mostly sucks: it's very slow, and typically very expensive compared to airfare. The trains frequently don't even have WiFi (outside the NE). They're really comfortable, though, I'll give them that. The coach seats are like 1st-class seats on airlines. But there's probably a bunch of reasons for all this: airlines are largely deregulated here in the US, and there's a ton of competition driving prices down. There's only one Amtrak, with zero competition. Amtrak has to rent space on the tracks from freight companies that own the tracks, and their trains take last place on the tracks (yep, freight gets priority here over passenger rail!). And their trains are generally horribly slow, since we don't have anything resembling high-speed rail, so they're not too attractive to anyone that values their time: no one really wants to spend 3 days (not exaggerating) on a train trip that they can do in 4 hours by airplane.

The competition thing alone is probably one big reason you're seeing that different in Germany. Government-owned agencies just cannot compete against private industry in most cases. When there's no competition and it's nearly impossible to get fired, that leads to an organizational culture which is bloated, ineffective, and overly expensive. I don't know if it's this bad in Germany, but here in the US, if you work at a government agency and need to just buy an office chair, it can take almost a year. Private companies don't work that way because they'd go out of business if they did.

Berlin–Munich is 5.5 hours, according to Google Maps.