The recent horrific events in Paris and the refugees fleeing from the violence in Syria reminded me of a particular effect of global warming: sea level rise. What, you ask, does a rise in seal level have to do with terrorist activities and people trying to escape a war-torn country? Simply that people now living in low lying areas are going to be forced by the sea to move to higher ground.
That doesn't sound so significant until you consider the sheer magnitude of the number of people who will be affected.. A sea level rise of 10 meters is quite possible in this century especially in view of the feeble efforts being made by industrialized nations to reduce greenhouse gas emissions. By some estimates, a rise of this magnitude would force the relocation of as many as three quarters of a billion people. If you consider the effects of mass migrations of the past, the thought of so many people on the move should at least give you pause.
Along with the large numbers of refugees that would need to be dealt with, the competition for resources is likely to lead to increased radicalism – i.e. a fertile recruiting ground for ISIS – and an increase in conflict among and within States.
If this is even remotely likely, some really hard, long-range thinking is called for.