A recent report based on a survey of 6,000 people by the Swiss bank UBS suggests growth in the number of people taking to the skies could halve as people choose to fly less, according to various news media including the BBC.
21% of those surveyed across the UK, France, Germany and the US said they had decided for environmental reasons to reduce the number of flights they took over the last 12 months.
Part of this could be due to the flight shame movement, a term coined in Sweden where it is known as flygskam.
Global air travel has been growing by between 4% and 5% a year. Plane makers Airbus and Boeing predict growth will continue at this rate, which would double passenger numbers by 2035.
Taking into account increases in flight taxes and flight shame, UBS predicts annual growth of 1.5% in Europe and 1.3% in the US. By contrast, Airbus predicts 3.0% growth in Europe and 2.1% in the US.
Switzerland is currently considering introducing a flight tax of between CHF 30 and CHF 120 depending on seat class and flight distance.