Elsevier

Political Geography

Volume 31, Issue 7, September 2012, Pages 444-453
Political Geography

Climate triggers: Rainfall anomalies, vulnerability and communal conflict in Sub-Saharan Africa

https://doi.org/10.1016/j.polgeo.2012.08.004Get rights and content

Abstract

The mounting evidence for climate change has put the security implications of increased climate variability high on the agenda of policymakers. However, several years of research have produced no consensus regarding whether climate variability increases the risk of armed conflict. Many have suggested that instead of outright civil war, climate variability is likely to heighten the risk of communal conflict. In particular, erratic rainfall, which reduces the availability of water and arable land, could create incentives for violent attacks against other communities to secure access to scarce resources. Yet, whether groups resort to violence in the face of environmentally induced hardship is likely to depend on the availability of alternative coping mechanisms, for example through market transfers or state accommodation. This suggests that the effect of rainfall anomalies on communal conflict will be stronger in the presence of economic and political marginalization. We evaluate these arguments statistically, utilizing a disaggregated dataset combining rainfall data with geo-referenced events data on the occurrence of communal conflict in Sub-Saharan Africa between 1990 and 2008. Our results suggest that large negative deviations in rainfall from the historical norm are associated with a higher risk of communal conflict. There is some evidence that the effect of rainfall shortages on the risk of communal conflict is amplified in regions inhabited by politically excluded ethno-political groups.

Highlights

► We study the link between rainfall variability and communal conflict. ► We focus on Sub-Saharan Africa between 1990 and 2008. ► Negative rainfall deviations are associated with a higher risk of communal conflict.

Introduction

As we see mounting evidence for global warming, the societal implications of climate change are ranking high on the agenda of policymakers. One of the suggested societal consequences of greater climate variability and more erratic rainfall patterns is an increased risk of armed conflict (c.f. Boko et al., 2007). In the words of US President Barack Obama, climate change “will fuel more conflict for decades” (The Economist, 2010). Africa is often held to be particularly vulnerable to political instability following climate change, as dependence on rain-fed agriculture and low institutional coping capacity make adaptation more difficult. For example, the conflicts in Darfur, Sudan, have been cited as evidence of this trend (Ban, 2007).

Academic research on the climate–conflict linkage has yet to produce conclusive evidence in support of such contentions. Instead, many large-N studies find little support that droughts or other sources of climate-induced environmental stress are associated with an increased risk of armed conflict in Africa, or anywhere else. After several years of systematic research, the relationship between climate and conflict thus remains speculative (Gleditsch, 2012). However, whereas most large-N studies focus on violent threats posed against state authority, case-based accounts of environmentally related conflicts tend to concern inter-group clashes over access to grazing land, water holes, livestock or cropland, that do not directly involve the agents of the state (e.g. Hagmann & Mulugeta, 2008; Meier, Bond, & Bond, 2007). Deviations from normal rainfall patterns undermine the livelihoods of large segments of African populations who base their income and food supply on rain-fed agriculture. We suggest, as have others, that economic desperation creates incentives for violent attacks against other communities in a direct effort to alter the allocation of scarce resources. Such violent responses to climate-induced hardships are more likely in a context of economic marginalization and political exclusion, since other coping strategies – for example offered through market-based mechanisms or state accommodation – are unavailable (Raleigh, 2010).

Based on the above observations, this article examines the association between rainfall anomalies and communal conflict in Sub-Saharan Africa. In spite of the importance of communal conflict for understanding the human security implications of climate change, cross-national studies that move beyond case-based accounts and anecdotal evidence are sparse. This paper addresses this gap by providing the first large-N analysis across a large number of countries over time of the impact of rainfall anomalies on the risk of communal conflict. To strengthen our inferential leverage we use a spatially disaggregated dataset combining rainfall data of high spatial resolution with geo-referenced events data on the occurrence of communal conflict in Sub-Saharan Africa, 1990–2008. To examine how economic and political marginalization influences the risk of communal conflict following rainfall anomalies, we use quantitative indicators of poverty and political exclusion of ethno-political groups at the local level.

Our results suggest that large negative deviations in rainfall from the historical norm are associated with a higher risk of organized violence between societal groups. There is some evidence that political exclusion plays a role in mediating this relationship: the effect of intra-annual rainfall shortages on the risk of communal conflict is amplified in regions inhabited by politically excluded ethno-political groups. Political and physical vulnerability might thus reinforce each other, and make violent coping strategies to climate induced hardships more likely. Contrary to our expectations, our results do not provide any evidence that poverty aggravates the risk of communal conflict following anomalies in precipitation patterns.

The paper proceeds by reviewing the existing literature on the environmental sources of armed conflict. It then outlines the theoretical framework for the association between rainfall anomalies, vulnerability and communal conflict. After presenting data and research design, we discuss our empirical findings. The final section concludes.

Section snippets

Previous research

Since the mid-1990s there has been a growing interest in understanding the societal implications of climate change. The issue of resource availability is central in this discussion. Rising temperatures will be associated with greater rainfall variability and increase the frequency of severe weather events such as droughts and floods (Boko et al., 2007). A likely consequence is increased scarcity of renewable resources such as water and strains on the productivity and availability of arable land.

Rainfall anomalies, vulnerability and communal conflict

One possible reason for the mismatch between the strong claims in the environmental security literature and the weak empirical evidence offered by the large-N literature is the almost exclusive focus on armed rebellion against the state in the latter. Much of the arguments within the former literature suggest, however, that pressure on vital resources such as water or arable land is particularly likely to heighten inter-group tension, and spur violence between groups rather than attacks against

Data and research design

This article examines the relationship between rainfall anomalies and the occurrence of communal conflict in Sub-Saharan Africa, and empirically evaluates how this relationship is conditioned by local patterns of economic and political vulnerability. Through our empirical approach, we aim to remedy some of the shortcomings identified in much of the existing large-N literature on climate and conflict. First, we switch the focus from civil war to communal conflict, a form of organized violence

Results and analysis

In this section we present the results from multivariate regression analysis of the influence of rainfall anomalies on the risk of communal conflict. Given the dichotomous nature of our dependent variable, we use logit regression, and report robust standard errors adjusted for clustering on the administrative unit. In Table 1 we evaluate the first hypothesis that rainfall anomalies increase the risk of communal conflict. We start by looking at negative rainfall anomalies. The results reported

Conclusions

This study is the first large-N analysis across a large number of countries over time of the impact of climate variability on communal conflict in Sub-Saharan Africa. Utilizing a spatially disaggregated research design and drawing on new geo-referenced event data on armed conflicts, we statistically explore how rainfall anomalies are associated with communal conflict. The results suggest that communal conflict is more likely in dry years, which is consistently shown in two alternative measures

Acknowledgements

We would like to thank Erik Melander, Halvard Buhaug, Julian Wucherpfennig, Allan Dafoe, the Editor of the journal and three anonymous reviewers for their very useful comments, and Ralph Sundberg and Mihai Crocu for help with data. Financial support from the Swedish International Development Agency and the Swedish Center for National Disaster Science (CNDS) is gratefully acknowledged. The authors are listed in alphabetical order, equal authorship implied.

References (74)

  • R. Bates

    Modernization, ethnic competition and the rationality of politics in contemporary Africa

  • BBC

    Floods inundate farmlands in southern Somalia

    (2001)
  • N. Beck et al.

    Space is more than geography: using spatial econometrics in the study of political economy

    International Studies Quarterly

    (2006)
  • N. Beck et al.

    Taking time seriously: time-series-cross-section analysis with a binary dependent variable

    American Journal of Political Science

    (1998)
  • T.A. Benjaminsen

    Does supply-induced scarcity drive violent conflicts in the African Sahel? The case of the Tuareg rebellion in northern Mali

    Journal of Peace Research

    (2008)
  • W.D. Berry et al.

    Testing for interaction in binary logit and probit models: is a product term essential?

    American Journal of Political Science

    (2010)
  • M. Boko et al.

    Africa, climate change 2007: impacts, adaptation and vulnerability

  • C. Boone

    Political topographies of the African state: Territorial authority and institutional choice

    (2003)
  • T. Brambor et al.

    Understanding interaction models: improving empirical analyses

    Political Analysis

    (2006)
  • H. Buhaug

    Climate not to blame for African civil wars

    Proceedings of the National Academy of Sciences

    (2010)
  • H. Buhaug

    Dude, where's my conflict?

    Conflict Management and Peace Science

    (2010)
  • Buhaug, H., Gleditsch N. P., & Theisen, O. M. (2008). Implications of climate change for armed conflict. Background...
  • H. Buhaug et al.

    It's the local economy, stupid! geographic wealth dispersion and conflict outbreak location

    Journal of Conflict Resolution

    (2011)
  • M.B. Burke et al.

    Warming increases the risk of civil war in Africa

    Proceedings of the National Academy of Sciences

    (2009)
  • L.E. Cederman et al.

    Why do ethnic groups rebel? New data and analysis

    World Politics

    (2010)
  • Center for International Earth Science Information Network (CIESIN) and Centro International de Agricultura Tropical (CIAT)

    Gridded population of the world (GPW3) data collection

    (2005)
  • P. Collier et al.

    Breaking the conflict trap: Civil war and development policy

    (2003)
  • A. Deaton

    Commodity prices and growth in Africa

    Journal of Economic Perspectives

    (1999)
  • A. Deaton et al.

    International commodity prices and macroeconomic performance, and politics in Sub-Saharan Africa

    Princeton Studies in International Finance

    (1995)
  • EC-FAO Food Security Programme

    The global administrative unit layers (GAUL) GAUL/Doc 01

    (2008-12-15)
  • M.L. Felix et al.

    Peoples of Africa: Enthnolinguistic map

    (2001)
  • H. Fjelde et al.

    Rebels against rebels

    Journal of Conflict Resolution

    (2012)
  • Fjelde, H., Østby, G. (2010). Economic inequality and non-state conflicts in Africa. Paper presented at the 2010 Annual...
  • N.P. Gleditsch

    Armed conflict and the environment: a critique of the literature

    Journal of Peace Research

    (1998)
  • N.P. Gleditsch

    Whither the weather? Climate change and conflict

    Journal of Peace Research

    (2012)
  • K.S. Gleditsch et al.

    Richardson in the information age: geographic information systems and spatial data in international studies

    Annual Review of Political Science

    (2012)
  • T.R. Gurr

    Why minorities rebel: a global analysis of communal mobilization and conflict since 1945

    International Political Science Review

    (1993)
  • Cited by (194)

    View all citing articles on Scopus
    View full text