Well, Jonty, you can claim that, but it doesn't make it so. Even the airline industry itself, a party with highly vested interests and therefore likely to have a high degree of bias, now publicly admits that aviation contributes to man-made global warming. Given the results of the Intergovernmental Panel on Climate Change, the most comprehensive study on climate change to date, it would be patently absurd for an airline to continue to maintain innocence in this matter. As such, BA has published a simplified summary of its actions on its website, available
here.
Specifically, BA states that, "…aviation was responsible for 2% of CO2 emissions - the most important greenhouse gas - and around 3.5% of man-made global warming in total… …According to UK government estimates, aviation emissions of CO2 are about 5% of the national total… …The contribution of aviation to total radiative forcing is likely to be higher." It goes on to assert that "[a]irlines can therefore make a contribution to reducing global warming by buying fuel efficient aircraft and operating them efficiently."
Now I'm not saying there is a consensus among the general public, the vast majority of whom do not have sufficient information to take a qualified decision on the matter. But airlines are fully aware of the role they play in global warming, as are governments (hence the Kyoto Protocol and other measures, which are very difficult to stomach for MPs because they risk reducing economic competitiveness). The reason these officials take the actions they do is because they have been comprehensively advised by scientists, the vast majority of whom do share in the consensus that you claim does not exist.
Furthermore, if we take your premise - that we
might be contributing to global warming - it stands to reason that our action must still be to limit our emissions
in case it proves that we do cause global warming. Only by adopting the absurdly optimistic stance that our actions
cannot contribute
whatsoever to global warming could we possibly justify not curbing our emissions. Such an approach is tantamount to a four-year-old sticking his fingers in his ears and chanting "I can't hear you!" repeatedly. And about as effective.