Quantifying the Influence of Climate on Human Conflict

Program in Science, Technology and Environmental Policy, Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ 08544, USA.
Science (Impact Factor: 31.48). 09/2013; 341(6151):1235367. DOI: 10.1126/science.1235367
Source: PubMed

ABSTRACT A rapidly growing body of research examines whether human conflict can be affected by climatic changes. Drawing from archaeology,
criminology, economics, geography, history, political science, and psychology, we assemble and analyze the 60 most rigorous
quantitative studies and document, for the first time, a striking convergence of results. We find strong causal evidence linking
climatic events to human conflict across a range of spatial and temporal scales and across all major regions of the world.
The magnitude of climate’s influence is substantial: for each one standard deviation (1σ) change in climate toward warmer
temperatures or more extreme rainfall, median estimates indicate that the frequency of interpersonal violence rises 4% and
the frequency of intergroup conflict rises 14%. Because locations throughout the inhabited world are expected to warm 2σ to
4σ by 2050, amplified rates of human conflict could represent a large and critical impact of anthropogenic climate change.

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Available from: Solomon M Hsiang, Jul 03, 2015
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