Lord, there are days . . . look, people, the connection between climate change and any sort of social behavior is complex and difficult to trace.  I’ve mentioned before that the connection between climate change and conflict is not at all straightforward.  So too the connection between climate change and migration/refugees.  But no matter how many times we say this, people still go with the simple connection – climate change = more refugees/more migration.  Take, for example, this bit of reporting at CNN.

The devastating effects of climate change and conflicts fought over ever-scarcer resources such as water could cause a surge in migration that experts fear the world is totally unprepared for.

At least one billion people will be forced from their homes between now and 2050 by such forces, the international charity group Christian Aid predicted in a recent report.

Oh, for God’s sake.  Look, we’ve been over this before.  There will be relatively few new refugees, and all I can offer is a very qualified maybe about more migration.  Why do I say this?
First, a refugee, by definition, is someone who is forced to move (a nebulous issue) and then does move across an international border.  People who are forced to move but stay in their country after moving are called internally displaced people (IDPs) – this is not merely terminology.  Refugees have all sorts of rights that IDPs do not.  And most work on climate and migration suggests very short moves, meaning we might see a surge in climate-related IDPs, but probably not climate refugees.  Well, that and the fact that international law does not consider climate-related events as legal “forcings” that can result in refugee status.  So, most people will not clear a border, and those that do will not be recognized under current law as refugees.
Second, there are a hell of a lot of assumptions here about what causes people to move and why in the context of environmental change.  I’ve written on this in refereed journals, and a chunk of the first half of my book addresses this issue indirectly.  Simply put, any decision to move incorporates more than an assessment of one’s material situation – it is a complex decision that takes into account a whole range of factors, including social considerations and opportunities elsewhere.  These factors are locally-specific, and therefore any wide, general claim about the number of likely refugees is mostly crap – we simply don’t know.
So where did the crappy analysis come from?  Oh, right, this crap story was built on a completely crap report that I complained about just recently.  Crap begetting crap.  Super.