Dear Umbra, Your recent answer to the plane/train question prompts me to ask something that has always bothered me but that my little old brain can't figure out on my own. I know that planes are worse than other forms of transportation, but the plane is going to fly whether I'm on it or not. So I always wonder if it's really better for me to drive to Chicago in my car than it would be to grab an empty seat on a plane that's already going that way. In that sense, isn't it like the bus? Yes, the bus pollutes more than my car, but it has to drive the same route every day whether I get on or not. I understand that by buying a plane ticket, I am generating demand that the airlines then supply, in theory. They might add more routes and so forth. But that seems more like an issue for a regular traveler, not for a once-a-decade plane trip to Europe. Please help me get my head around this! Beverly B.,
Louisville, Ky.