Revisiting the link between natural disasters and civil conflicts

This research note revisits the link between natural disasters and civil unrest and argues that the relationship is inverted U-shaped. Natural disasters are likely to stimulate political violence, but only when the severity of the disaster is modest. We test this argument by replicating five existing studies and find partially supportive results. After we add a squared term of the variable that measures disaster severity to the model, we find an inverted-U relationship between natural disasters and conflict incidents, conflict duration, and rebel resilience. Models that use conflict onset as the dependent variable, however, do not show clear nonlinearity.