Abstract
<jats:p>The intersection of climate change and international security has emerged as one of the most consequential analytical frontiers in twenty-first-century international relations. This paper develops a multidimensional framework for analyzing how environmental stress shapes interstate conflict and cooperation, advancing beyond existing scholarship that treats climate as a background variable. Drawing on securitization theory, environmental peacebuilding literature, and the most recent empirical syntheses of climate–conflict linkages, the paper articulates seven interconnected dimensions of climate security—resource competition, migration pressures, territorial change, food security, cooperation opportunities, securitization dynamics, and infrastructure vulnerability—situated within a multilevel structure spanning local, national, regional, and global scales. Through comparative analysis of transboundary water governance, climate-induced migration, Arctic geopolitics, food-system disruption, and environmental peacemaking initiatives, the paper identifies both pathways to conflict and opportunities for cooperation. The findings indicate that climate security outcomes are contingent rather than deterministic, mediated by political institutions, economic conditions, and social structures; that institutional density determines how much climate stress a domain can absorb; and that conflictual and cooperative trajectories frequently co-occur within the same regions and dyads. The paper contributes to international relations theory by bridging materialist and constructivist perspectives on climate security, offering policy-relevant insights for diplomatic practice, international law, and multilateral governance. It concludes by identifying priority areas for future research, including the climatization of security institutions, the legal implications of disappearing states, the security externalities of mitigation policy, and the potential for climate cooperation to serve as a confidence-building measure in contested geopolitical environments.</jats:p>