icting messages ? The IPCC on con fl ict and human security

Violence seems to be on a long-term decline in the international system. The possibility that climate change would create more violent conflict was mentioned in scattered places in the Third and Fourth Assessment Reports from the Intergovernmental Panel on Climate Change (IPCC), published in 2001 and 2007 respectively. The empirical literature testing for relationships between climate change and various forms of conflict has undergone a major expansion since then. The report from Working Group II of the Fifth Assessment Report contains a much more careful assessment of the climate change-conflict nexus. The Human security chapter reports high agreement and robust evidence that human security will be progressively threatened as the climate changes. But as far as the impact on armed conflict is concerned, it paints a balanced picture, concluding that while individual studies vary in their conclusions, ‘collectively the research does not conclude that there is a strong positive relationship between warming and armed conflict’. The chapter also argues that climate change is likely to have an influence on some known drivers of conflict, and this point is reiterated in other chapters as well as the Technical summary and the Summary for policymakers. A chapter on ‘Emergent trends. ’ has a somewhat more dramatic conclusion regarding a climate-conflict link, as does the Africa chapter, while a methods chapter on ‘Detection and attribution’ dismisses the climate-change-to-violence link. The entire report is suffused with terms like ‘may’, ‘has the potential to’, and other formulations without any indication of a level of probability. Overall, the Fifth Assessment Report of the IPCC does not support the view that climate change is an important threat to the long-termwaning of war. Still, the report opens up for conflicting interpretations and overly alarmist media translations. © 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). New threats to security? Globally, in the first decade after World War II, an average of some 300,000 people per year died in battle-related violence. In the first decade in the newMillennium the figure had shrunk to around 44,000. An influential argument has beenmade that this is part of a broad and long-term decline in the use of violence in human affairs (Pinker, 2011). However, theworld is not yet a peaceful place by any means, and the decline in armed group violence is certainly not monotonic. Many potential threats to peace have been proposed, including environmental change, and more specifically climate change. For instance, United Kingdom and Germany have pushed Oslo (PRIO), P. O. Box 9229, editsch), ragnhild@prio.org Ltd. This is an open access article u for climate change to be recognized as a security issue by the UN Security Council and the Council has held three debates on the issue (2007, 2011, 2013). In the most recent session, Germany's representative stated that ‘with the current trends of CO2 emissions, climate change will continue and lead us into a 4 degrees scenario with devastating consequences e with a high risk to economic growth and a grave threat to peace and security. ’ (German Mission to the UN, 2013). In academic circles, strong statements have also been made about a climate-conflict link. Notably, a prominently published article by Burke, Miguel, Satyanath, Dykema, and Lobell (2009) foresaw 393,000 additional battle-related deaths in sub-Saharan Africa over a 28-year period up to 2030 if temperatures continued to rise and new conflicts were as deadly as those in the period 1981e2002. However, there is no consensus in the scholarly community about such dire projections of future climate wars; in fact most observers conclude that there is no robust and consistent evidence for an important relationship between climate change and conflict (Bernauer, B€ ohmelt, & Koubi, nder the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). N.P. Gleditsch, R. Nordås / Political Geography 43 (2014) 82e90 83 2012; Scheffran, Brzoska, Kominek, Link,& Schilling, 2012; Theisen, Gleditsch, & Buhaug, 2013). 1 Although climate change is likely to have severe consequences for people around the world, in particular for already vulnerable populations, the link to violent conflict is a potential but contested consequence. In this article, we examine how the Intergovernmental Panel on Climate Change (IPCC) has dealt with the question of a climate-conflict nexus in its three most recent assessment reports over the period 2001e14. We focus in particular on the most recent report fromWorking Group II of the Fifth Assessment Report (AR5) (IPCC, 2014a), which has by far the most comprehensive treatment of this issue. While the two previous reports dealt with the question of a climate-conflict nexus in an unsystematic and sometimes haphazard manner, the Human security chapter of the new report (Ch 12) presents a more balanced and comprehensive assessment. However, there are significant inconsistencies between different chapters in AR5. Other problems with IPCC's evaluation of the climate-conflict nexus are the lack of clear adjudication of what existing evidence shows and a failure to provide a solid assessment of the probability of future climate conflict and its severity if it occurs.