I thought I'd share the following link:
The article has some interesting points about aviation emissions. Specifically, some points that challenge the accepted 'wisdom' that aviation emissions per passenger are similar to a car's emissions over a similar distance.
Aviation emissions are 3% of US GHG emissions. (but increasing rapidly)
Today's aircraft are 70% more efficient than those of only 40 years ago.
High altitude emissions disproportionately damage the environment.
Stats used to claim parity with car emissions assume 100% full airplane versus 1 car with 1 occupant. (unlikely that a car has only 1 occupant over long distances. e.g vacation, also load factors of 100% are unrealistic)
CE Delft Study claims air travel least fuel efficient among cars, buses, trains, even on trips over 1500km.
The gist of the article hints that these environmental costs are leading to political events to reduce them, especially on short-haul flights. The mechanisms to do so are not fully articulated, but the article points out that jet engine efficiency is improving at 1% per year, and that an alternative to energy-dense kerosene is unlikely.
I think this points to uncertain horizons in terms of the business environment for LCCs who would be the obvious victim of regulations designed to reduce short-haul flights. Another issue that comes to mind is that as this understanding seeps through into the public discourse, there is a possibility that increasing numbers of individuals may reconsider their vacation plans in terms of their environmental ramifications. For example, the significant contribution of GHG made by flying may make the the idea of taking a flight to enjoy wild nature far less appealing. (Note, the article states that only 1 in 4 passengers is travelling on business)
I'm interested to hear what others think about this issue and the future of more environmentally sensitive aviation technologies.