Temperatures, food riots, and adaptation: A long-term historical analysis of England

A large body of research indicates that environmental conditions can influence the risk of social unrest. However, we know little about how these effects may change in the long run. Are they likely to remain constant or do they change over time – for example as a consequence of human adaptation? To investigate this question, we rely on a disaggregated analysis of England over a period of more than 300 years. Combining data on geo-referenced food riots with reconstructed climate data, we first assess the impact of annual temperatures on social unrest over the period 1500–1817. We then use our long-term time-series dataset to assess the temporal heterogeneity of year-to-year associations between temperatures and social conflict. Our models show a substantive negative correlation between temperatures and food riots in the aggregate. This association, however, seems to be highly inconsistent over time and largely confined to the 18th century. In addition, we find evidence of decadal processes of adaptation: past exposure to adverse weather conditions dampens the effect of current exposure. Taken together, these findings underline the importance of considering temporal heterogeneities when assessing the climate–conflict nexus and caution against any simple extrapolations of observable present-day effects of environmental conditions into the future.