Leave a Smaller Carbon Footprint on the Road

About three years ago, I received an invitation to attend a premiere of an award-winning documentary produced by my brother-in-law. It was in San Francisco, which immediately appealed to me.

Yet I recoiled when I realized how much carbon and other pollution my eight-hour-plus roundtrip flight from Chicago would release into the atmosphere. I felt it was an arrogant use of carbon-intensive travel to see one film.

A non-stop one-way flight would generate between 210 and 254 kilograms (463 to 560 pounds) of carbon dioxide per passenger, Google Flights estimates. I'd have to plant a tiny forest to offset that, although ironically a more expensive flight produced slightly less CO.

Since I care about my carbon footprint, I experienced a pang of what Greta Thunberg, the Swedish climate activist, would call flygskam — that is, guilt over jet-powered air travel and the pollution it generates. Thanks to 21st century technology and awareness of lower-carbon travel options, we can approximate how much our wanderlust is affecting the planet. Yet the solution to reducing the overall carbon impact of travel may come down to some simple actions and modest data analysis.

Tools like Google Flights can estimate the carbon emissions of specific flights. While the algorithm they use to estimate the amount of carbon dioxide created by each flight is a bit wonky, it's a useful metric if you're concerned about the impact of CO, which accounted for 80% of all U.S. greenhouse gas emissions from human activities in 2022.

Google uses the U.S. Environmental Protection Agency's greenhouse gases equivalency calculations to estimate the number of trees it would take to sequester — or lock up — the difference in CO emissions between a flight you want to take and the typical flight on the same route. In other words, Google uses the ability of trees to absorb carbon from the atmosphere as a rough comparison baseline for jet flight emissions.

OK, that's not ideal math for a direct measure of greenhouse gas pollution, but it can help you to reduce your carbon impact by knowing which flights emit more greenhouse gases into the atmosphere than others.

Why focus on carbon emitted by flying? Because along with ocean shipping — think gargantuan container ships powered by highly polluting, tar-like "bunker" fuel — jet flights are the most carbon- and particulate-intensive forms of travel.

Aviation and maritime shipping currently account for 6% of global emissions, reports the non-profit environmental group Giving Green. That could rise to 30% by 2050 if fossil-fuel consumption by aircraft and cargo ships continues growing and their decarbonization efforts fail to catch up to other industries.

Sometimes the lower carbon footprint is a matter of simple division. The more passengers on an airplane, bus or train, less CO is emitted per person. Carbon emissions even vary depending on the type of jet engine, aircraft, number of passengers and length of flight. Some airplanes are more fuel efficient, carry more people and can go longer distances than others.

Not surprisingly, if you can travel in an all-electric vehicle — and have plenty of charging stations on your route — that's the least carbon-intensive option when considering personal vehicles. Although this obviously doesn't work for transoceanic flights, it's a reasonable alternative for drivable locales.

"Our research shows that on average, new battery electric vehicles emit about 60% to 68% lower lifecycle greenhouse gas emissions than average comparable new gasoline cars in the United States," says Peter Slowik, the U.S. Passenger Vehicle Lead at the International Council on Clean Transportation.

What can you do to cut your carbon travel impact? You can reduce travel overall, focus on lower-carbon modes or buy carbon offsets. While convenient, the third choice is problematic. Carbon offsets are offered and sold through third parties and there is no reliable monitoring and independent certification of these programs.

"I don't trust buying offsets," says Daniel Stein of Giving Green. "According to a recent study of the most popular offset projects, the vast majority were deemed to be essentially worthless."

It's not difficult to make a more earth-friendly travel choice. Here are some useful decision points:

Choose the lowest-carbon impact mode. According to Visual Capitalist, the transportation modes with the lowest carbon impact are national rail (such as Eurostar and Amtrak); electric vehicles, gasoline cars, motorcycles and buses. On the top of the most carbon-intensive list are private jets and medium and long-haul commercial flights. The difference between certain modes is profound: "Taking a train instead of a short flight can reduce your emissions by 84%."

Choose nonstop flights. A great deal of fuel is burned in take-offs, so if you can reduce the number of stops on the way to your destination, the total pollution is generally lower.

Drive an EV if possible. As noted above, if you can get to your destination without tailpipe emissions, great. But even a hybrid vehicle is better than a flight. Although charging stations are becoming more numerous, you may need to do more planning if driving an EV.

Travel Locally and Regionally Using Mass Transportation. When traveling from the suburbs to the city — my most frequent travel direction — I choose commuter trains, city buses, rapid transit and walking. It's rare that citybound traffic isn't like a traversing a clogged artery, so I can read, check email and relax on the train. Plus I don't have to pay exorbitant parking fees in the city. I may even walk to the train station or to my urban destination if weather permits. I always get more exercise and have always enjoyed urban strolls in pedestrian-friendly cities.

Credit: Visual Capitalist

Will knowing how much your travel pollutes the environment actually alter your behavior? Honestly, it hasn't changed my bucket list of desired, long-distance travel destinations nor has it curtailed my business travel. For distances over 500 miles, jets are still the preferred mode of travel. Yet my growing anxiety has prompted me to think twice about flying shorter distances.

While I didn't fly to San Francisco to attend the film premiere mentioned above, it triggered a much deeper level of travel-related decision making. I recently chose a commuter train and Amtrak over driving to a conference that involved travel under 400 miles. While it took somewhat longer than driving, I was able to read and write in comfort. I doubt if most of the other passengers on the train were as concerned about reducing their carbon impact as I was, yet they were doing their part, too, and I thank them for not driving or flying.

Planting more trees is also a key strategy, which I'm also doing, yet reducing carbon-intensive travel is one of my prime lifestyle goals.