Quite possible for Europe to charge landing fees based on ghg emissions for all planes arriving/departing.

That would be great. I think if they were being aggressive enough, there would probably be less demand for airport expansion, because there would be fewer flights. I don't currently see any way to curtail the carbon from the airline industry that wouldn't involve raising the price so drastically that people would fly less often.

The point is they act as a deterrent. The money raised can be used to mitigate the effects of the emissions.

Cap and trade does in fact make it so that polluters pay for ghg emissions. Why do you say that we can't "conceivably pay for"?