This is the stark conclusion from the Envisioning Tourism in 2030 report, published by the Travel Foundation, which found destinations and tourism businesses "must take action now" on sustainability if they are to reach the goal.
It comes after global policymakers and climate planners attending Cop27 were urged to combine current measures with "significant" investments and incentives for bringing forth the greenest forms of transport, and limits on the most polluting.
The team behind the report used a "systems modelling" technique to explore future scenarios for global travel and tourism.
