My guess is that approach would do relatively little to mitigate the overall environmental impact. If you raise fees enough then private airplanes, with much higher CO2 per passenger, become more desirable. To make air travel “worth it” airlines - who have fleets of aircraft with 35-50 year useful lifespans - would dial back to business and first class only.
Spitballing it, I’d say we could reduce flying passenger count by 80% but only see a 10-20% reduction in net CO2 generation. And then, to offset the loss in 80% travel, you would need to find an alternative travel source that is only 12-20% of the use of an aircraft per passenger mile for actual traveled miles just to break even on net passenger travel. 20% seems to be the marker for national rail vs most air travel, so we’re at best break even. And for passenger ocean ships, the net cost per passenger in CO2 is higher than flying, so it’s a lose-lose for any trans-Atlantic or trans-Pacific travel (not to mention the week travel time each way).
My guess is that approach would do relatively little to mitigate the overall environmental impact. If you raise fees enough then private airplanes, with much higher CO2 per passenger, become more desirable. To make air travel “worth it” airlines - who have fleets of aircraft with 35-50 year useful lifespans - would dial back to business and first class only.
Spitballing it, I’d say we could reduce flying passenger count by 80% but only see a 10-20% reduction in net CO2 generation. And then, to offset the loss in 80% travel, you would need to find an alternative travel source that is only 12-20% of the use of an aircraft per passenger mile for actual traveled miles just to break even on net passenger travel. 20% seems to be the marker for national rail vs most air travel, so we’re at best break even. And for passenger ocean ships, the net cost per passenger in CO2 is higher than flying, so it’s a lose-lose for any trans-Atlantic or trans-Pacific travel (not to mention the week travel time each way).