Probably the best way to cut air travel pollution is with a combination of high-speed electric trains between all major cities (make it convenient to get around

Probably the best way to cut air travel pollution is with a combination of high-speed electric trains between all major cities (make it convenient to get around without flying) along with a ration book for air travel - everyone is allotted one trip per year, second trip has a surcharge, third and subsequent trips have massive surcharges growing to astronomical numbers. The average person does not fly in a given year. Those that do fly tend to take no more than one trip. A very small percentage of frequent flyers account for the bulk of air travel. An explicit rationing system would allow "regular" people to still fly occasionally and would have huge benefits for cutting air travel overall while impacting only the frequent flyers. People would be forced to ask if they REALLY need to fly out to NY for that meeting. The boosts to the VR/Skype/virtual presence/hologram/conferencing field would be enormous.