Monbiot is one of those making a career from playing Cassandra. I've forgotten how he got around while promoting his book. Sailboat I expect.

If we can reduce emissions 25% by just being less stupidly wasteful, and say another 25% through engineering efficiency that leaves us reducing flights to 1/3 the current level. Viable renewable or part renewable fuels could mean we don't have to reduce at all and could in fact increase the trips when planes are needed by cutting out the stupid trips where trains could do the job better and faster.