What Your Flight History Reveals About Your Carbon Footprint
That’s what Google engineers in Zurich hoped would happen when they pioneered this project in 2019, the year that “flygskam” took off as a phrase in English-speaking countries. They designed the algorithm to factor in the fuel efficiency of each aircraft’s engine as well as the number of passengers that can fit on board that kind of plane. (Flying economy and flying nonstop tend to decrease your emissions.)
Picking the most fuel-efficient tickets can sharply reduce your carbon footprint without much sacrifice. One working paper by the International Council on Clean Transportation, subtitled “The Case for Emissions Disclosure,” found that choosing the least-polluting itinerary on a route could emit 63 percent less CO₂ than the most-polluting option, and 22 percent less than the average flight.
For a while, users had to dig around to find Google’s carbon emissions information. But last month, just before the climate summit in Glasgow, Google put CO₂ emissions directly into the search results for all to see. The company intends to share its model with other travel platforms, hoping to make carbon emissions estimates more standard and thus more credible in the eyes of the public, James Byers, a senior product manager for Google, told me.
Currently, carbon footprint estimates for flights are all over the map. For instance, Kayak, another travel site that allows customers to search for low-emitting flights, frequently comes up with estimates that are vastly different from Google’s. (Kayak’s estimates come a German nonprofit called Atmosfair, which uses a different methodology.)
Google engineers hope that climate guilt will drive consumer preferences and incentivize companies to invest in aircraft that are more fuel efficient. That could speed the development of electric planes and greener jet fuels. That’s a wonderful vision. I hope it works.
But carbon calculators have a dark side, too. The concept of a personal carbon footprint has been promoted by BP, the fossil fuel giant largely responsible for the notorious Deepwater Horizon oil spill.
A special climate-conscious part of BP’s website is a one-stop shop for climate guilt. It has a carbon footprint calculator that estimates that a generic flight from Boston to Minneapolis would put 0.62 metric tons of carbon emissions in the air, more than twice Google’s estimate for the JetBlue flight. Then it graciously offers to take my money to offset those emissions by buying solar panels in India, fuel-efficient cookstoves in Mexico and wind turbines in China. My climate sin of visiting my sister would be absolved for the low price of $2.80.