Environmental Scarcities and Violent Conflict: Evidence from Cases

Within the next fifty years, the planet's human population will probably pass nine billion, and global economic output may quintuple.Largely as a result, scarcities of renewable resources will increase sharply.The total area of high-quality agricultural land will drop, as will the extent of forests and the number of species they sustain.Coming generations will also see the widespread depletion and degradation of aquifers, rivers, and other water resources; the decline of many fisheries; and perhaps significant climate change.If such "environmental scarcities" become severe, could they precipitate violent civil or international conflict?I have previously surveyed the issues and evidence surrounding this question and proposed an agenda for further research. 1Here I report the results of an international research project guided by this agenda. 2Following a brief review of my original hypotheses and the project's research design, I present several general findings of this research that led me to revise the original hypotheses.The article continues with an account of empirical evidence for and against the revised hypotheses, and it concludes with an