AskPablo: Planes, Trains, and Automobiles

ptauto.jpgThis week on AskPablo we will be looking at various transit modes and their relative ecological impact. I have received a few related questions on this matter so I will try to address them all. Please make sure that you submit questions for the next few weeks. Otherwise I will have to start making stuff up…
Let’s start by looking at a few transit modes. We already covered the “beef-powered cyclist” a few weeks ago so I would revisit the greenhouse gas impact of cycling. According to one source a single-occupant vehicle travelling at highway speeds emits about 0.101 kg of CO2 per passenger-kilometer, or about 1kg (2.2 lbs) per 10km (6.2 miles). We all know that there are many ways to improve this. You could drive a hybrid (But is that really better, given the batteries required? Maybe some other time…), carpool, keep your tires inflated to the proper pressure, keep your car maintained, etc.


A bus travelling at the same speeds emits around 0.041kg per passenger-mile, or 2/5ths as much as the car. Unfortunately there are some setbacks to this transit mode. Many of us don’t like sitting next to smelly people named Earl (no offense to any Earls that might be reading this) for 16 hours on a Greyhound bus from Bakersfield to Salinas. Travelling by train is even more efficient, at least as far as carbon emissions are concerned. Sadly, unless you are in Europe, it will probably take you about twice as long to get where you are going.
Assume that we are the jet-setting corporate type. What is our impact? Well, it’s somewhere around 0.214kg per passenger-kilometer, over twice the impact of driving. There are several factors with flying though. It was recently discovered that flying at night does more damage to our environment so no more red-eye flights, OK!? Also, the greatest amount of fuel is consumed during takeoff and landing when the wing flaps are extended to produce maximum lift at relatively low speeds. So, if you are flying across the country with multiple layovers mother earth will be angry with you. And you don’t want to upset your mother…
So, in summary: walk or ride your bike, take mass-transit or carpool, and fly during the day with as few stops as possible. When you can’t eliminate a trip, don’t feel guilty. It is very easy to offset your carbon contribution these days. Just last week I offset all of my 2007 carbon emissions of my vehicle for a mere $40 (Yes, I have a car, but I waited until I was 25 before I got my first car and rode my bike everywhere before then, OK?) using DriveNeutral . You can also offset other travel and lifestyle emissions through DriveNeutral, TerraPass, and others.
After you have offset your various carbon-related guilt please do me a favor and think of a cool question to AskPablo. See you next week!