Finding a flight is getting easier and easier thanks to specialized search engines. But too few consider ecotourism. So, making an eco-friendly choice of a plane ticket, including the carbon footprint of flights quickly becomes complex. A real nightmare.
Indeed, multiple parameters impact the carbon footprint. Some on which you have control : the path (its distance) and the number of flight legs. Others are unsure. The type of aircraft for example, can change until the last moment on the airline freewill. Then some are completely unknown or very opaque, such as the number of passangers who will book on the same flight, airlines rules to spare fuel, the risk to have an airport closed…
At the end, it is impossible to know which will be the best flight. Nevertheless I say that we must do our best to reduce our impact.