Winter is Coming : The Long - Run Effects of Climate

This paper investigates the long-run effects of climate change on conflict by examining cooling from 1400-1900 CE, a period that includes most of the Little Ice Age. We construct a geo-referenced and digitized database of conflicts in Europe, North Africa, and the Near East from 1400-1900, which we merge with historical temperature data. We first show that during this time cooling is associated with increased conflicts. Then, turning to the dynamics of cooling, we test for the presence of intensification and adaptation. We do this by allowing the effects of cooling over a fifty-year period on the change in conflict during the same period to depend on the extent of cooling during the preceding fifty-year period. We find that intensification dominates adaptation – the effect of cooling in increasing conflict triples if the same area experienced cooling during the preceding period.