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Green by a Mile: Go Carbon Neutral on Your Next Flight


When it comes to the environment and your travel, sometimes a mile is a mile is a mile.

Let’s start with this stat: planes are roughly comparable to cars in fuel consumption per passenger mile, at least with respect to carbon dioxide output. It makes for an easy comparison; a 60-hour cross-country car trip burns up about the same amount of fuel per passenger, and has the same “carbon footprint,” as a five-hour cross-country flight.

I don’t think a traveler has to be a member of Greenpeace to reach the end of a 3,000-mile drive and think “Whoa, I burned up some fuel on this trip.” However, the same person might step off a plane after 4.5 hours eastbound from Los Angeles to New York and not ponder even for an instant the resultant fuel consumption, greenhouse gas emissions or carbon footprint of their trip. How bad can the damage be when you barely had time to fall asleep?

The truth is that air travel does even more damage than you’d imagine — so much that many travelers are looking into ways to neutralize the carbon emissions from their flights. A whole host of companies have sprung up to help travelers go “carbon neutral,” an increasingly popular term that was declared the 2006 word of the year by the New Oxford American Dictionary.

It remains to be seen whether carbon offsetting is the wave of the future or just a passing fad — but with evidence mounting about the overwhelming ecological effects of air travel, it’s well worth considering how you can do your part for the environment on your next trip.

A Mile Is a Mile: Quick and Dirty Look at the Science

Air travel has a particularly negative impact on the atmosphere due to two factors, expressed here in as close to lay terms as I can muster: 1) planes emit a stew of other harmful gases in addition to carbon dioxide, and 2) gases released in the upper atmosphere where planes cruise have a much greater impact than gases released on the ground due to something called the “radiative forcing” effect. The sum total of the damage is about 1.9 times that of driving a relatively fuel-efficient car.

Radiative forcing notwithstanding, it’s much easier simply to call a mile a mile. Since most of us are doing so little about the problem already, to quibble over the exact radiative forcing effect is a bit like working inside the Beltway, where people would rather argue over how to do something than actually do it. As convenient as it would be out here in the real world to live that way, we can’t, so let’s use the mile = mile metric.

Thus, if the average American drives 10,000 – 15,000 miles each year, it takes only a trip to Europe for a West Coaster, a trip to Hawaii for an East Coaster or a couple of cross-country flights to do as much damage (or more) as you do during an entire year of commuting and cruising in your car.

Politics Cedes to Science (Finally)

While global warming has considerable staying power as a hot-button topic among politicians, virtually no reputable scientists and increasingly few citizens see it merely as a political issue any longer. After years in the political wilderness, global warming has come to be accepted as scientific fact by most Americans — or close enough to fact to act.

Many travelers are willing to do something about it — but are we willing to stop traveling? In this global economy, and in a country where extended families might live all over the country (my own family has folks in New Jersey, Florida, San Diego and Seattle), forgoing air travel entirely isn’t going to happen. And the greater benefits of global travel are multifold and diverse, whether you focus on cultural, political or economic factors. So what can we do about it?

Carbon Offsetting: Solution or Panacea?

For better or worse, the concept of “carbon offsetting” has gained considerable currency in the media as one way to mitigate the environmental impact of many facets of modern living. The concept is fairly simple: for every mile you travel, or rather every ton of carbon dioxide your mode of travel causes to be released into the atmosphere, you pay a small fee to enable other folks to work on solutions to mitigate the damaging ecological effect of your travel.

There are some great things about carbon offsetting:

Unlike a lot of environmental science, the concept is extremely easy to grasp. Spew a bunch of gases into the atmosphere + plant a tree that can chew up those gases = zero sum total.

To let the market help solve some of its own problems is a promising long-term approach; several companies mentioned below are making it very easy to participate, which is a critical component of any popular movement.

For insanely busy working Americans who simply do not have the resources to plant 40 trees every time they fly to Chicago, paying a very reasonable amount to have someone else do this work is both effective and realistic.

But there are also some problems:

It is a classic “pay-to-play” or even “blood money” gambit — if you have the dough, you can buy off any damage as well as any guilt over your travel habits, which, on a global and historical scale, are pretty extravagant if you are taking transatlantic flights. It feels a bit like the practice of purchasing indulgences 500 years ago, and the practice certainly has its Martin Luther-like detractors.

Paying $6.99 to have someone plant trees still doesn’t change the fact that you abetted the burning of a heap of fossil fuel and the dumping of a lot of harmful gas.

Considerable debate remains on how best to spend the funds — wind farms or tree farms? Solar solutions or “manure into methane”? Indigenous reforestation or “tree cultures”? While tree planting is one of the most popular options for carbon offsets — not to mention one of the easiest for average people to understand — many experts point out that trees only sequester carbon until they die, at which point the carbon will be rereleased into the atmosphere. Other debates center around questions of whether the companies and agencies doing the work are actually delivering on their promises.

Is carbon offsetting the solution? These are early days, so it’s hard to know how effective the practice will be, but doing nothing isn’t much of a good option either. It’s fair to assume that some of the nagging issues will start to shake out over time, but for now some folks will want to know where their money is going. Paying six bucks to take a chance on your trip resulting in a sum zero environmental impact doesn’t seem like a high price to pay given the alternative — unless you’re buying property in Sacramento angling that it will be oceanfront in a few decades.

Now at a Booking Site Near You

Notwithstanding the nascent (and somewhat trendy) nature of the concept, carbon offsetting has reached the mainstream, most prominently on some of the major travel booking sites, including Expedia and Travelocity. Expedia has a partnership with TerraPass, a for-profit carbon offsetting company; Travelocity has a partnership with The Conservation Fund’s Go Zero program, a nonprofit effort.

(The issue of whether a nonprofit is better than a commercial company for this type of work is also a divisive issue in the world of general do-gooding; many believe that adding a profit motive to what has typically been “charity work” is the best way to improve and sustain these efforts. On the other hand, one obvious upside of using the nonprofit is that you can deduct the expense at tax time.)

When booking a flight on Expedia, the last screen you see before confirming the purchase of your trip to Knoxville is the option to “Customize your trip to Knoxville,” which includes such “Featured Activities and Services” as the Expedia Flight Protection Plan, an airport lounge pass, a subscription to a glossy travel magazine and, sure enough, the option to “Fly Green with TerraPass,” one of the leading travel carbon-offsetting companies.

Based on calculations of the carbon footprint of your trip (typically measured in cubic tons, which you can calculate on the TerraPass site), Expedia and TerraPass offer three contribution levels:

Short-haul flight of 2,200 roundtrip miles at $6.99 each
Cross-country flight of 6,000 roundtrip miles at $16.99 each
International flight of 12,000 roundtrip miles at $28.99 each

So we’ve finally come to the point where taking responsibility for the impact of our travel qualifies as a “Featured Activity and Service.” Call it progress!

If you prefer not to mingle your travel booking with your charitable and environmental efforts, or if you want to extend your carbon offsetting donations to other parts of your life, you can visit the Web sites of any number of competing carbon offsetting outfits to calculate your carbon consumption and make your contribution directly. See our list of carbon offset companies.

Other Ways to Offset Your Environmental Impact While Traveling

Reducing your environmental impact while traveling can be almost absurdly easy (and I’m not talking about driving without air-conditioning during summer, wearing down coats in your hotel room or other such unpleasantries):

When you leave your hotel room, turn down the heat or air-conditioning until you return, and turn off the lights.

Use the “no room service needed” option offered at many hotels. At home, you don’t change your bedsheets, use a different towel, vacuum perfectly tidy rugs or scrub your sink every single day, as is the case at even the most modest hotels. If everyone in every hotel in America were to use this option, the amount of water and energy saved on washing machines alone would have an impact.

Use public transportation when traveling. In many cities riding the subway, the Underground, the El trains and the like can be a wholly satisfying way to get to know your surroundings. Folks who zip from one tourist attraction to another in a taxi learn about exactly those things: taxis and tourist attractions. It’s all the actual living in between that makes a great city great.

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