Following the workshop, members of the researcher and policy communities were invited to provide their insights. Here, we provide summaries and context for these papers, highlighting the broader themes of research and policy interactions for climate change and conflict.
The overview piece in this issue is prepared by Busby (2018), Taking Stock: The Field of Climate and Security . In this essay, Busby surveys the progression and state of the science on climate and security over the past 15 years and outlines potential directions for policy-relevant research. He argues that researchers should focus their efforts on elucidating the intermediary mechanisms and contextual factors that may link climate change to conflict rather than continue to debate whether or not there are any direct associations. While efforts that focus on the causal pathways may be better matched to the needs of policymakers, Busby emphasizes that the existing academic evidence thus far is too limited and inconclusive to inform policy on specific practices, institutional arrangements, and other factors to mitigate the risk of climate-related conflict and insecurity . He suggests investigating the following pathways and contextual factors: shocks to food prices or changes in agricultural production, economic mechanisms, environmentally driven migration, and the role of institutions . He further stresses the potential for more complex interactions, such as disasters, which might lead to conflict via economic mechanisms or inadequate government response. He also addresses the strengths and limitations of the different methods. Statistical analysis may be useful in identifying hotspots of vulnerability and developing early warning systems similar to FEWSNET . However, Busby urges scholars to apply theories and knowledge to specific cases and ideally comparative case studies to generate the kind of contextual understanding and to ask questions that address the policy-makers’ need to design effective interventions .
In their public statements, high-level policymakers and influencers frequently emphasize the importance and influence of a few cases that are popularly believed to be driven by or indicative of the types of conflict and security risks that may be observed due to climate change [21, 22]. Three regions that are frequently mentioned are the ongoing conflict in Syria [23, 24], the vulnerabilities in the Lake Chad Basin [25, 26], and the pastoral-herder and other conflicts in the Horn of Africa , although the research and policy communities do not always draw the same conclusions about the contribution of climate change relative to political and economic factors. In his paper, Ide (2018) demonstrates how the proposed links between the 2006–2009 drought in Syria and the 2011 onset of civil war in Syria exemplifies the shortcomings of the climate-conflict literature [23, 24, 28]. He reviews the evidence for the causal chain that is frequently presented in the literature:  climate change contributed to the severe drought,  this drought disrupted agriculture and livelihoods in rural areas,  the loss of livelihood led to large scale migration to the urban centers, and  the additional population strained resources in the receiving areas, prompting grievances that contributed to anti-regime protests and ultimately led to the civil war. Ide finds support for the migration into the urban centers due to the effects of the drought on agricultural incomes, but emphasizes that the magnitude of these effects relative to political and economic factors is not well understood. He finds much weaker evidence for attribution of the drought to anthropogenic climate change and for the link between migration and the onset of conflict. However, challenges with integrating quantitative and qualitative research methodologies as well as the lack of rigorous theories on how the environment influences conflict limit the cumulation of policy-relevant knowledge on the Syria case and climate-conflict linkages more broadly. Ide argues that scholars should draw on the full range of methods and theories to build general knowledge about causal and contextual factors , knowledge that might help policy-makers to prevent future conflict and instability.
In addition to improving the basis for how contextual factors affect the potential influence of climate change on conflict, there is also a need to understand the interactions with policy, specifically aid, development, and diplomacy. Investigating the links between disasters, such as those due to extreme weather events, and collective violence highlights both the contextual factors and the influence of a wide range of policies. In his review of recent research on disasters and violence, Brzoska (2018) finds some support for an increase in collective violence; however, the actions of individuals and policy-makers can alter not only the magnitude but also the directionality of this association . First, he stresses that political factors and institutions influence not only the potential for disasters to lead to violence, but also the severity of a disaster . Second, he emphasizes that the effects of weather are generally small and secondary and tend to reinforce existing conditions and processes. As such, disasters may hasten processes of peace-building and de-escalation as well as precipitating or exacerbating conflict . To identify practical entry-points for reducing the incidence and duration of violent conflict precipitated by disasters, Brzoska recommends research into the pre-event conditions (e.g., livelihoods, ethnic marginalization, and institutions) and post-disaster mechanisms that may lead to conflict . Possible post-disaster pathways include shifts in economic and resource constraints, grievances and perceived injustice, migration, and shocks to the resources and capabilities of collective actors and institutions.
Climate adaptation and mitigation policy also has the potential to influence the onset and incidence of conflict, specifically through altering land use . While the stresses posed by the physical impacts of climate change on land use and the implications of these effects for human security and conflict are often addressed in the literature, Froese and Schilling (2018) describe a broader and more complex nexus between climate change, land use, and conflict that emphasizes the role of individual and policy responses to climate change Froese and Schilling under review. Climate change mitigation projects, such as the siting of renewable energy generation or forest conservation programs (for example REDD/REDD+) can result in changes in land use, the costs and benefits of which often accrue unequally [35, 36]. When these changes impact human security, such as livelihoods and quality-of-life, it may exacerbate existing conflicts or create new ones . Froese and Schilling particularly highlight the likelihood of land use change to negatively impact already poor and marginalized populations, due in part to their weak or informal land tenure . They also outline a pathway from climate adaptation to conflict, whereby actions with diffuse benefits (i.e., flood protections) may have land use impacts that disproportionately affect specific individuals or groups that may already be marginalized. Despite the gaps in the understanding of how these policies may be related to conflict, Froese and Schilling suggest a list of best practices for managing the potential for adverse effects from these policies, namely community participation, comprehensive impact analyses, and trust building. These activities may be even more valuable when implementing climate policy in situations with existing conflicts.
Institutions underlie both the potential for climate to introduce security risks and the effectiveness of policies to mitigate adverse impacts . At the same time, research on the role of institutions and their responses to climate security is limited and tends to focus on global governance, such as the UN Security Council [10, 40]. Krampe and Mobjörk (2018) provide insight into how policymakers define climate security risks and the opportunities and organizational constraints for managing these risks. They conduct a comparative case study of the policy documents from security Intergovernmental Organizations (IGOs) in Asia and Africa to investigate how these organizations conceptualize and respond to climate security risks . They find that while Western IGOs tend to understand climate risk in terms of state security, the organizations in developing countries frame the challenges of climate change and conflict in terms of human security, such as food access. This allows for more entry points for climate security; however, policy implementation commensurate with these risks is limited both by the issues of sovereignty and trust between states and organizational divisions within IGOs. Additionally, the parts of the organizations that are charged with managing the climate risks are often secondary compared to other functions of the IGO.
Finally, Schweizer (2018) starts a discussion on the use of decision support for conflict and climate risks through the use of scenario analysis Schweizer under review. She outlines how existing methodologies of foresight and decision support, and advances in the application of these methods to climate change problems more broadly, can be built on to learn from existing evidence and provide tools for learning and experimentation. Schweizer (2018) surveys a range of existing methods for applying foresight to decision support, and their various strengths and limitations—including knowledge requirements, transparency and potential for bias, and suitability for purpose. For example, even if the state of theory and empirical consensus is advanced, the validity of predictive exercises is likely to weaken over time as climate change shifts human and natural systems further from their historical states. While novel in the climate-conflict space , Schweizer (2018) discusses how the use of scenario analysis has resulted in important advances in climate change research [43, 44]. Additionally, she encourages climate-conflict researchers to engage with the scenario frameworks developed by the climate change research community: the Representative Concentration Pathways (RCPs) and the Shared Socioeconomic Pathways (SSPs) [43, 45]. Working from the RCP-SSP scenarios not only allows for an analysis of the co-occurrence of different socioeconomic and climatic conditions, but also facilitates the comparability of studies and therefore the accumulation of knowledge on climate-conflict links.