What transport mode causes the most global warming?

William Atkins
Saturday, 03 January 2009 01:47

Science - Climate

The abstract to their paper stated, “After 20 and 100 years the response in net temperature is 7 and 6 times higher, respectively, [for road transport] than for aviation.”

In other words, cars/trucks are seven times as bad as airplanes with respect to global warming.

In addition, “Aviation and shipping have strong but quite uncertain short-lived warming and cooling effects, respectively, that dominate during the first decades after the emissions. For shipping the net cooling during the first 4 decades is due to emissions of SO2 and NOx.”

Fuglestvedt stated, “In contrast to road transport, air transport has several strong, but short lasting, effects on the global temperature. But there are large uncertainties in our understanding of these effects. It is important to work towards reducing this uncertainty.” [ScienceDaily]

He added, “When we quantify and compare the climate impacts of the different transport sectors, the conclusions will vary strongly depending on which method and climate indicator is used and the adopted time perspectives...."

And, "This is a significant step forward compared to earlier work. In our previous study we quantified the climate impacts in terms of accumulated radiative forcing, which is similar to the Global Warming Potential (GWP) method used in the Kyoto Protocol.”

They added, “On a longer timescale, the current emissions from shipping cause net warming due to the persistence of the CO2 perturbation. If emissions stay constant at 2000 levels, the warming effect from road transport will continue to increase and will be almost 4 times larger than that of aviation by the end of the century.”

Read more about the transport-global warming study in the CICERO article "Road emissions dominate global transport emissions."