It’s no secret flying is Bad for the climate, but just how harmful our jet-setting, Airbnb-hopping lifestyles really are has been tough to pin down. Now a study has crunched the numbers, making it much harder to plead ignorance about the environmental impact of your next vacation.
Turns out, those trips contribute to humanity’s climate-warming CO2 emissions bigly. Like, four times more than we thought. And you’ll be shocked to hear that U.S. vacationers are the biggest CO2 burpers of all.
The study, published Monday in Nature Climate Change, compiled data on 160 different countries to arrive at a global estimate of the tourism industry’s carbon footprint. It found that between 2009 and 2013, that footprint grew from about 3.5 to 4.5 billion metric tons of CO2 annually, accounting for about eight percent of global greenhouse gas emissions, or more than triple the annual carbon emissions of Brazil.
Previous estimates pegged tourism’s slice of the global carbon pie as just two or three percent, but as co-author Ya-Yen Sun of the University of Queensland told Earther via email, those estimates didn’t consider direct or indirect emissions from the supply chains that support tourism. The new study did, which means that in addition to accounting for flights, ground transportation, and hotels, it attempted to factor emissions associated with manufacturing all those tchotchke you’re buying at the airport and those surf’n’ turf dinners you’re enjoying by the beach.
Overall, the authors found that U.S. vacationers produced nearly a billion tons of CO2 in 2013, by far the largest contribution of a single country. Most travel-related carbon emissions could be attributed to vacationers from wealthy countries traveling to other wealthy countries.
Perhaps most troublingly of all, the study found that global demand for vacations is outstripping the industry’s efforts to decarbonize. In other words, emissions from the multi-trillion dollar industry are expected to grow into the foreseeable future, barring some dramatic changes.
“For those concerned about their personal emissions, this could be a wake-up call,” Jonathan Foley, environmental scientist and Executive Director of the California Academy of Sciences, told Earther via email. “Not only do we need to think about the emissions of our airline flights, and so on, but we also should be mindful of the kinds of foods we eat, and trinkets we buy, along the way. Just like climate-conscious consumers try to do at home.”
The study goes further, suggesting that worried consumers can take fewer international trips, which have outsized CO2 footprints, and book more vacations close to home. It also notes that policy-makers have largely failed to take the tourism industry’s emissions seriously on the global stage—international aviation, for instance, is currently excluded from the Paris climate agreement, and the only UN-backed aviation emissions standards on the books are weak as hell.
There’s no shortage of things we could be doing, both individually and collectively, to address the issue. If we don’t? Island nations like the Maldives and natural treasures like the Great Barrier Reef might one day be nothing more than memories.