Buying carbon offsets won’t stop global warming, but if you’re traveling, it’s your best individual option for reducing your carbon footprint.
For the average person, airline travel, which New York Times writer Elisabeth Rosenthal has called “the biggest carbon sin,” is one of the largest individual contributors to climate change. In October 2013, meteorologist and Slate writer Eric Holthaus vowed to give up flying completely, after calculating that air travel accounted for almost half of his household’s carbon emissions. Holthaus, admittedly, previously flew a great deal for business and pleasure, but even one cross-country flight can contribute to a significant portion of an individual’s annual carbon emissions. A round-trip coach ticket from New York to San Francisco accounts for 2 metric tons of carbon dioxide—compare that with the average American, whose annual carbon footprint is roughly 19 metric tons. First class seats, which take up more space and therefore increase the amount of fuel used per passenger, leave an even bigger carbon footprint—up to nine times larger than their economy counterparts, according to a 2009 World Bank study. So while the overall environmental impact of aviation might seem relatively negligible (the aviation industry is responsible for 2 percent of global emissions, compared to 26 percent from the nation’s energy supply, or 14 percent from agriculture), for frequent-flyers, air travel is a significant slice of their individual contribution to climate change.