The thermodynamic meaning of negative entropy : Nature. Civil conflicts are associated with the global climate : Nature. 1Homer-Dixon, T. F. On the threshold: environmental changes as causes of acute conflict. Int. Secur. 16, 76–116 (1991)Article Google Scholar 2Diamond, J. Collapse: How Societies Choose to Fail or Succeed (Viking, 2005) Google Scholar 3Miguel, E., Satyanath, S. & Sergenti, E. Economic shocks and civil conflict: an instrumental variables approach.