The impact of climate change on conflict is an important but controversial topic. One issue that needs to be resolved is whether or not climate change exacerbates conflict over the long term. With this in mind, we investigated the relationship between climate change and conflict among Classic Maya polities over a period of several hundred years (363-888 CE). We compiled a list of conflicts recorded on dated monuments, and then obtained temperature and rainfall records for the region. Subsequently, we used a recently developed time-series method to investigate the impact of the climatic variables on the frequency of conflict while controlling for trends in monument number. We found that there was a substantial increase in conflict in the approximately 500 years covered by the dataset. This increase could not be explained by change in the amount of rainfall. In contrast, the increase was strongly associated with an increase in summer temperature. These finding have implications not only for Classic Maya history but also for the debate about the likely effects of contemporary climate change.
Bibliographical noteWe received financial support from the Social Sciences and Humanities Research Council of Canada (767-2011-0159 and 895-2011-1009), the Natural Sciences and Engineering Research Council of Canada (RGPIN04040-2014), the Canada Research Chairs Program, the Canada Foundation for Innovation, the British Columbia Knowledge Development Fund, and Simon Fraser University. We thank Michael Blake, Julia Cole, James Conolly, Arthur Demarest, Keith Dobney, Gyles Iannone, Mark Maslin, Arne Mooers, Stephen Shennan, Adrian Timpson, Seam Ulm, Andrew Weaver, David Webster, Bernard Wood, and Jennifer Wurtzel for their helpful feedback on this paper.
- human-environment interaction
- climate change
- North America
- Classic Maya