One or WW's sites reminded me of a possible alternative explanation for the abandonment of the settlement at Skara Brae. A couple thousand years earlier, the sudden massive subsidence of steep banks of sediment off the Norwegian coast created a tsunami that would surely have sent a high wave over Skara Brae a couple thousand years before it became inhabited. Another tsunami whose traces have not been identified could have killed all the inhabitants far more readily than a storm, and thus ended human occupancy.