Results of event coincidence analysis (ECA) for the trigger test based on the occurrence of disasters that coincide with an armed-conflict outbreak within the same month. Results for four different country groupings are resolved in four individual panels, whereas results for different disaster types are indicated by the color coding. Coincidence rates are displayed for different damage threshold levels by individual bars with increasing damage threshold from left to right. For some threshold levels, the trigger coincidence rate is zero. Filled segments indicate coincidence rates that are significant at the 95 percent level. Graphic: Schleussner, et al., 2016 / PNAS

26 July 2016 (Potsdam Institute) – Climate disasters like heat-waves or droughts enhance the risk of armed conflicts in countries with high ethnic diversity, scientists found. They used a novel statistical approach to analyze data from the past three decades. While each conflict is certainly the result of a complex and specific mix of factors, it turns out that the outbreak of violence in ethnically fractionalized countries is often linked to natural disasters that may fuel smoldering social tensions. This finding, to be published in the Proceedings of the US National Academy of Sciences, can help in the design of security policies – even more so since future global warming from human-made greenhouse-gas emissions will increase natural disasters and therefore likely also risks of conflicts and migration. “Devastating climate-related natural disasters have a disruptive potential that seems to play out in ethnically fractionalized societies in a particularly tragic way,” says lead author Carl Schleussner from the Berlin think-tank Climate Analytics and the Potsdam Institute for Climate Impact Research (PIK). Almost one quarter of conflicts in ethnically divided countries coincide with climatic calamities, the scientists found; importantly, this is even without taking climate change into account. “Climate disasters are not directly triggering conflict outbreak, but may enhance the risk of a conflict breaking out which is rooted in context-specific circumstances. As intuitive as this might seem, we can now show this in a scientifically sound way,” says Schleussner, who has also been a research fellow at Humboldt University, Berlin, at the Integrative Research Institute on Transformations of Human-Environment Systems (IRITHESys). “We’ve been surprised to which extent results stick out compared to e.g. inequality” Previous research often either focused on climatic variables such as temperature increase that cannot be directly translated into societal impacts, or has been limited to case studies. The new study moves beyond that by focusing directly on natural disaster-related economic damage data, collected by the international reinsurance market leader Munich Re. Using the mathematical method of event coincidence analysis, this is combined with a conflict dataset established by security research, and a common index for ethnical fractionalization. The study looks at the period 1980-2010. “We’ve been surprised by the extent that results for ethnic fractionalized countries stick out compared to other country features such as conflict history, poverty, or inequality,” says co-author Jonathan Donges, co-head of PIK’s flagship project on co-evolutionay pathways COPAN. “We think that ethnic divides may serve as a predetermined conflict line when additional stressors like natural disasters kick in, making multi-ethnic countries particularly vulnerable to the effect of such disasters.” “A very special co-benefit of climate stabilization: peace” The study cannot provide a risk assessment for specific states. Since armed conflicts and natural disasters are fortunately rare events, data from single countries is necessarily limited and does not suffice for statistical analyses. “Armed conflicts are among the biggest threats to people, killing some and forcing others to leave their home and maybe flee to far-away countries. Hence identifying ethnic divide and natural disasters as enhancing destabilization risks is potentially quite relevant,” says co-author Hans Joachim Schellnhuber, director of the Potsdam Institute for Climate Impact Research. “Human-made climate change will clearly boost heatwaves and regional droughts. Our observations combined with what we know about increasing climate-change impacts can help security policy to focus on risk regions.” Several of the world’s most conflict-prone regions, including North and Central Africa as well as Central Asia, are both exceptionally vulnerable to human-made climate change and characterized by deep ethnic divides. “So our study adds evidence,” Schellnhuber concludes, “of a very special co-benefit of climate stabilization: peace.”

Climate disasters increase risk of armed conflict in multi-ethnic countries

ABSTRACT: Social and political tensions keep on fueling armed conflicts around the world. Although each conflict is the result of an individual context-specific mixture of interconnected factors, ethnicity appears to play a prominent and almost ubiquitous role in many of them. This overall state of affairs is likely to be exacerbated by anthropogenic climate change and in particular climate-related natural disasters. Ethnic divides might serve as predetermined conflict lines in case of rapidly emerging societal tensions arising from disruptive events like natural disasters. Here, we hypothesize that climate-related disaster occurrence enhances armed-conflict outbreak risk in ethnically fractionalized countries. Using event coincidence analysis, we test this hypothesis based on data on armed-conflict outbreaks and climate-related natural disasters for the period 1980–2010. Globally, we find a coincidence rate of 9% regarding armed-conflict outbreak and disaster occurrence such as heat waves or droughts. Our analysis also reveals that, during the period in question, about 23% of conflict outbreaks in ethnically highly fractionalized countries robustly coincide with climatic calamities. Although we do not report evidence that climate-related disasters act as direct triggers of armed conflicts, the disruptive nature of these events seems to play out in ethnically fractionalized societies in a particularly tragic way. This observation has important implications for future security policies as several of the world’s most conflict-prone regions, including North and Central Africa as well as Central Asia, are both exceptionally vulnerable to anthropogenic climate change and characterized by deep ethnic divides. SIGNIFICANCE: Ethnic divides play a major role in many armed conflicts around the world and might serve as predetermined conflict lines following rapidly emerging societal tensions arising from disruptive events like natural disasters. We find evidence in global datasets that risk of armed-conflict outbreak is enhanced by climate-related disaster occurrence in ethnically fractionalized countries. Although we find no indications that environmental disasters directly trigger armed conflicts, our results imply that disasters might act as a threat multiplier in several of the world’s most conflict-prone regions.

Armed-conflict risks enhanced by climate-related disasters in ethnically fractionalized countries