Global tourism accounted for 8% of the world's greenhouse gas emissions from 2009 to 2013, according to a paper published in Nature Climate Change — four times more than previous estimates.
The big picture: The biggest culprits for the jump were transportation, shopping, and food. Not surprisingly, high-income countries were the main drivers of the increased carbon footprint — but, as the cost barriers of international travel come down, more and more people worldwide are able to head abroad.