If you’ve ever tried to calculate your “carbon footprint“–the measure of the greenhouse gas emissions you create directly or indirectly as you live your life–then you know that your footprint grows larger and larger with each trip you take on an airplane.  Like the cars we drive, the planes we fly in burn lots of fossil fuels and emit greenhouse gases as a result. 

Scientists say jet airplanes also contribute to global climate change through the “contrails” they leave in their wake and the effect this has on how the sun’s earth-warming radiation is trapped in our atmosphere.

This photo from NASA shows how the particles and condensation--contrails--left in the wake of jet airplanes effect cloud formations that attract and trap the sun's radiation thereby contributing to harmful climate change.

 According to a forthcoming study from Standford engineering professor Mark Jacobson, “commercial aircraft flights have contributed between four to eight percent of global surface warming since air temperature records began in 1850.”  You can read more about the complex scientific interactions that cause this warming here.  In the meantime, let’s focus on the ways in which the professor thinks the airline industry and the flying public it serves can start to fix the problem.

First, we can reduce the amount of fossil fuels we need to burn per flight by reducing the weight of airplanes and the cargo they carry.  The lighter the plane, the less greenhouse-gas emitting fossil fuel it needs to burn.

Second, airlines must switch to hydrogen-based fuels that result in emissions that don’t create the same contrail problems caused by carbon-based fuels in use today.  Hydrogen-based jet fuels are already being used for the space shuttle, but it will cost lots of $ and take some time before they can be safely developed and widely deployed in the world’s commercial airline fleet.

(Of course the third option is that we all fly a lot less, but that’s a topic for another post).

So what does this have to do with baggage fees?

My hope is that fees for extra bags help us rethink how much we take along on trips.  If we travel lighter to avoid paying the fees, then the plane doesn’t need to burn as much fuel to get us there.  Those extra outfits, pairs of shoes, etc. come with an environmental cost.  Confronting that cost in dollars and sense is one way to get us to start changing our habits and expectations surrounding airline travel

Airlines are thinking “green” with these new fees, but not necessarily in the environmental sense.  To them it is all about the $$$.  Nonetheless, if we are going to get serious about slowing global warming and all its disastrous effects, then airlines must be able to seize on new more efficient technology that will reduce the negative climate imapcts of air travel.  Let’s make a deal with the airlines: We’ll live with the higher fees, if they are willing to up investment in new cleaner technology.