PUBLICATIONS: The Climate and Civil War Relationship

A series of recent papers by Marshall Burke, John Dykema, David Lobell, Edward Miguel and DRI Adjunct Faculty Shanker Satyanath documented evidence that warming temperatures caused by climate change increase the risk of civil war in Africa. The authors first established this connection in a published 2009 study, finding that warmer-than-average temperatures were linked to large increases in civil war in Africa between 1981 - 2002, with grave implications for the future:

We find strong historical linkages between civil war and temperature in Africa, with warmer years leading to significant increases in the likelihood of war. When combined with climate model projections of future temperature trends, this historical response to temperature suggests a roughly 54% increase in armed conflict incidence by 2030, or an additional 393,000 battle deaths if future wars are as deadly as recent wars. Our results suggest an urgent need to reform African governments’ and foreign aid donors’ policies to deal with rising temperatures.

Their results were challenged by Buhag (2010), who argued the findings were not robust as they relied on an "unorthodox" understanding of civil war, on "methodological fixes" and on the specific time period in question. In both an open letter to the Proceedings of the National Academy of Sciences, and in a new DRI working paper, Burke et al. dispute this assertion:

Buhaug’s dubious econometric choices in many of his specifications – including his decision not to control for country fixed effects or deal adequately with time trends in many specifications, or his willingness include endogenous regressors that bias all of his coefficients – further call into question his results. This of course does not imply that climate is solely “to blame” for African civil wars, as Buhaug’s provocative title would suggest that we are arguing. Rather it implies that during a particularly violent recent period in African history, variation in climate was a significant contributor to the incidence of large, destructive civil wars. We believe that this relationship is both robust and of significant interest to policy-makers tasked with reducing the incidence or impact of future conflicts.

The relationship between civil war and climate change still holds, in other words, even with alternatives measures. The authors do note, however, that this relationship has been considerably weaker in the past decade, a period of unprecedentedly high African growth and relative peace.

Read the original study on conflict and climate change here.

Read the letter to the Proceedings of the National Academy of Sciences here.

Read the latest working paper here.

WORKING PAPER: Understanding Transitory Rainfall Shocks, Economic Growth and Civil Conflict

Leaving aside these data and econometric issues, Ciccone’s surprising results do not survive obvious robustness checks.

Edward Miguel and DRI Affiliated Faculty Shankar Satyanath rebut Antonio Ciccone's (2010) assertion  that higher rainfall levels are, in fact, linked to more conflict -- a rejection of the Miguel, Satyanath and Serengeti (2004) conclusion that higher rainfall is associated with less conflict and more economic growth. But Ciccone's methods might have had some very fundamental errors:

Miguel, Satyanath and Sergenti (2004) use rainfall variation as an instrument to show that economic growth is negatively related to civil conflict in sub-Saharan Africa. In the reduced form regression they find that higher rainfall is associated with less conflict. Ciccone (2010) claims that this conclusion is ‘erroneous’ and argues that higher rainfall levels are actually linked to more conflict. In this paper we show that the results in Ciccone’s paper are based on incorrect STATA code, outdated conflict data, a weak first stage regression and a questionable application of the GMM estimator. Leaving aside these data and econometric issues, Ciccone’s surprising results do not survive obvious robustness checks. We therefore conclude that Ciccone’s main claims are largely incorrect and reconfirm the original result by Miguel, Satyanath and Sergenti (2004), finding that adverse economic growth shocks, driven by falling rainfall, increases the likelihood of civil conflict in sub-Saharan Africa.

Read the paper.