In terms of impact there's a generally accepted ~2.7X multiplier applied to flight emissions: "Among the reasons for this focus is that these emissions, becaus

In terms of impact there's a generally accepted ~2.7X multiplier applied to flight emissions: "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." [0] So you can look at 2-3% of co2, or you can look at impact and if we use the co2 proportion as a proxy of overall emissions, ~8% in terms of impact - and growing fast. https://en.wikipedia.org/wiki/Hypermobility_(travel) https://en.wikipedia.org/wiki/Hypermobility_(travel)