Some gases, including carbon dioxide and methane, trap heat in the atmosphere, producing a "greenhouse effect," and so make the planet warmer. The amount of greenhouse gases released by a particular activity is referred to as its "carbon footprint."
For Daniel Scott, a professor in the Department of Geography and Environmental Management at University of Waterloo in Ontario, the important finding in the study is "the scale of the contribution, at approximately 8%."
"People are often surprised at the size of their travel and tourism emissions," said Scott, who was not involved in the new research. "A frequent flyer can have a larger carbon footprint from their work or leisure travel than their entire carbon footprint at home."
Instead of a buying an electric car or slapping solar panels on your house, sometimes the biggest action you can take to reduce emissions is to travel differently, he said.