OK here are the DEFRA figures on emissions:
Total Emissions Per Vehicle
Average Car (25 mpg) – 1.39 lbs/mi
Total Emissions Per Person
Average Car/Single Driver – 1.39 lbs/mi
Average Car/Family of 4 - .34 lbs/mi
Train - .32 lbs/mi
Bus - .48 lbs/mi
Plane (250 mi trip) - .85 lbs/mi
Plane (600 mi) - .69 lbs/mi
Plane (3500 mi) - .56 lbs/mi
Figures for trains and planes are based on average occupancy (I assume). Bear in mind that CO2 emissions from planes are more harmful because they are higher up.
STATO - so what's your point? The amount of emissions from the aircraft will go up with the number of passengers - by choosing to fly on the plane you are adding to the amount of CO2 emissions. The train will also be departing as well. By getting on the plane you are adding to CO2 emissions - it's that simple.
Sorry but you're either part of the problem or you're part of the solution there's no way to avoid taking responsibility here - although I'm sure there are loads of people who choose to fly (I accept that some people have to) who know in their heart of hearts that it's environmentally damaging but try to rationalise their way out of it.