These tourists are also exhaling carbon dioxide, which has about as much effect on global warming (negligible) as long-haul flights to Australia. "The IPCC has

These tourists are also exhaling carbon dioxide, which has about as much effect on global warming (negligible) as long-haul flights to Australia. "The IPCC has estimated that aviation is responsible for around 3.5% of anthropogenic climate change." [https://en.wikipedia.org/wiki/Environmental_impact_of_aviation#Total_climate_effects https://en.wikipedia.org/wiki/Environmental_impact_of_aviati...]