For Passenger traffic:
Aviation:
0.24 Kg CO2 / psrmile short plane
0.18 Kg CO2 / psr mile long plane
Cars
0.44 Kg CO2 / psrmile
Bus
0.3 Kg CO2/ psrmile
Rail
0.16 kgCO2/psrmile
An engine consumes 30 units / km
For freight traffic: ( Kg CO2)
0.8 / ton-mile ( by air)
0.17 /............by truck
0.14..............by train
0.04 .............by Sea