When traveling, the question of flying or driving often comes up. Cars tend to be more fuel-efficient, thus making them the better all around choice regardless of other aspects. The average car producing 25-30 miles per gallon would generate 104 kilograms of CO2 regardless of the number of passengers in a trip from Philadelphia to Boston (300 miles) while a commercial jet would generate 184 kilograms of CO2 per passenger. Driving clearly releases less greenhouse gases into the environment, which would be less detrimental on the o-zone layer and have less of an impact on global warming. Even if someone is traveling alone they are still being more environmentally friendly, but if you throw carpooling into the equation with four people they would still only give off 104 kilograms of CO2 compared to the 736 kilograms that four people on a flight would generate. However being environmentally friendly comes with a price, driving costs more than flying typically would. For example a round trip from Santiago, CA to Boston, MA in a car would cost a total of 577$ while flying would only cost 280.40$, saving you practically 300$ on the trip. So the question of being environmentally friendly or saving money arises. In my opinion during these times we are going through, nothing should come before saving our planet. I think that the answer to this huge question is an easy one, driving is the better choice of the two, though it may cost more it will do far less damage to the environment and help make our planet greener.
http://environment.about.com/od/greenlivingdesign/a/fly_vs_drive.htm
http://environment.about.com/gi/o.htm?zi=1/XJ&zTi=1&sdn=environment&cdn=newsissues&tm=38&f=22&tt=2&bt=1&bts=1&zu=http%3A//www.fuelcostcalculator.com/