The Effect of Slow-Onset Climate Change on Migration Decisions

What explains why people choose to stay or emigrate in the face of slow-onset climate change? We leverage an original survey of prospective migrants who are exceptionally vulnerable to threats from climate change, but who possess the freedom to legally migrate to another country with relative protection from environmental degradation. Using a conjoint experiment, we assess subjects’ latent preferences before they depart by asking them the circumstances under which they would be more likely to move, given a set of randomly varying conditions representing migration push and pull factors. Our findings show that direct climate risks play a minimal role in prospective migrant decisions, with family- and health-related considerations being much stronger drivers. Our results ground climate mobility more firmly in the context of other migration and mobility decisions, and question widespread concern about the potential for slow-onset environmental degradation to directly produce massive flows, a significant consideration for future climate refugee programs.