VIEW: Climate and Conflict

As climate negotiations kick off in Copenhagen this week, mitigating a variety of potentially threatening effects caused by climate change will be on the minds of global leaders.  One of the issues on the table is the potential for climate induced armed conflict.  Climate change is likely to increase sea levels and alter precipitation patterns, thereby displacing millions of people and increasing the likelihood of conflict, says the prevailing logic.  But have warmer periods really been accompanied by increased conflict historically? 

Richard Tol of the Economic and Social Research Institute in Dublin and Sebastian Wagner of the research institute GKSS near Hamburg set out to answer that question, using data from previously published climate papers and the historical conflict compendium of conflict available at

They found that from 1550 to roughly 1750, there actually was a strongly inverted relationship between temperature and conflict, meaning that wars occurred more often in colder periods.  Around 1750 this relationship tapered off and temperature became insignificantly correlated with the level of conflict.  The researchers postulate that wars likely occurred during colder periods up until 1750 because colder temperature caused famine, which induced rival nations to fight over limited available food supplies.  However, as of the middle of the 18th century the Industrial Revolution enabled a more constant food supply through the introduction of systematic plant breeding, better irrigation techniques, and better food transport via roads and canals. 

Thus, Tol and Wagner are not suggesting that warmer temperatures in the future are going to reduce conflict, but rather that climate caused lifestyle disruptions can indeed cause conflict.  This is important to many types of businesses as well as governments: in order to prevent conflict, agribusinesses and agricultural researchers need to further develop high yield and drought resistant crops, farmers need to adopt the use of those crops, and businesses and politicians need to spur free trade and non-agricultural economic development.  If all of these things happen, countries will be more able to adapt to an influx of immigrants and lifestyles will be less disrupted by climate change, so there will be less to fight over. 

For more information, see the October 10-16th issue of The Economist

A Dispatch by SSC Intern Matt Logan