From New Scientist:

It is a potent image: desperate refugees fleeing environmental apocalypse, crossing boundaries to save their very lives. But this notion is flawed, said geographer David Thomas of the University of Oxford at the Planet Under Pressure meeting in London last week. Rather than seeing environmental migration as bad, we need to see it as part of the solution to environmental change.

Imagine a future in which migration becomes compulsory, as a method of dealing with climate change.  How would people react if they were forced to move across the country every few years?