Climate Variability, Armed Conflict, and Environmental Security Nexus in Nigeria’s North East: A Systematic Causal Analysis

The relationship between climate change, environmental degradation, and armed conflict in the Sahel and Lake Chad Basin has generated extensive scholarly and policy debate, yet causal pathway analysis in the specific context of North East Nigeria's Boko Haram insurgency and its environmental dimensions remains theoretically underdeveloped and empirically contested. This doctoral research develops and tests a systematic causal framework for the climate-conflict-environmental security nexus in Nigeria's North East, employing a multi-method design that combines causal process tracing, econometric analysis, and participatory scenario development. Panel data econometric analysis uses fixed effects and instrumental variable approaches to test associations between rainfall variability, food price shocks, lake shrinkage metrics, and conflict incident data from the Armed Conflict Location Event Dataset for the period 2010 to 2023. Qualitative process tracing is conducted through 70 interviews with community members, ex-combatants, security analysts, and environmental managers in Borno and Yobe states. Participatory causal mapping workshops with 90 participants in conflict-affected and adjacent communities co-develop causal path diagrams. The study finds evidence for multiple indirect causal pathways linking environmental stress and conflict, mediated by livelihood competition, governance failure, and elite resource capture, rather than a direct deterministic climate-conflict relationship. Original theoretical contributions include a multi-pathway causal model of the environmental security nexus applicable to Sahelian contexts, distinguishing between enabling, precipitating, and sustaining causal mechanisms. Policy implications address environmental peacebuilding opportunities, conflict-sensitive environmental programming, and early warning system integration with climate monitoring. Keywords: climate-conflict nexus, environmental security, North East Nigeria, causal analysis, Boko Haram.