Hypermobile travelers are "highly mobile individuals" who take "frequent trips, often over great distances." They "account for a large share of the overall kilometres travelled, especially by air."[1] These people contribute significantly to the overall amount of airmiles flown within a given society.[2] Although concerns over hypermobility apply to several modes of transport, the environmental impact of aviation and especially its greenhouse gas emissions have brought particular focus on flying.[3][4] Among the reasons for this focus is that these emissions, because they are made at high altitude, have a climate impact that is commonly estimated to be 2.7 higher than the same emissions if made at ground-level.[5]