Group offers green travel advice

WASHINGTON (AP) - If you want to travel green this holiday, take the bus or train, but if you must fly, stick with economy seating, according to the Union of Concerned Scientists.

UCS researchers compared trips by car, plane, train and bus to find out which transportation choices generate the fewest carbon dioxide emissions.

Among their conclusions:

—Airlines that have no first-class or economy-plus seats lower a plane's per-person emissions 10-15 percent because they're seating more passengers on each flight.

—If you're traveling alone or with one other person for trips of more than 500 miles, flying direct in coach is a better option than driving the average car in terms of per-person carbon emissions.

—Buses and motor coaches are the greenest travel option. UCS says that compared with flying coach, a couple traveling on a bus will cut their trip's carbon dioxide emissions 55 to 75 percent, depending on the distance traveled.

—Trains are green too, especially those in the Northeast that run primarily on electricity. Trains emit 60 percent less carbon per passenger-mile than a typical car with a single occupant, and 30 percent less carbon than a 500-mile trip on a small plane, UCS says.