This paper aims to improve the coverage of transboundary climate risk in case-study research for adaptation. It proposes a protocol to help researchers identify how their case studies can incorporate an analysis of transboundary climate risk, thereby supporting more holistic, effective, and just approaches to adaptation.

Existing climate risk assessment frameworks and supporting guidelines have significant strengths but also various challenges when applied to the novel context of transboundary climate risk. This is illustrated with reference to the impact chain framework. Its opportunities pertain to both its flexible form and systems-first focus while its constraints include an analytic emphasis on linear cause–effect relationships (that bely the complexity and uncertainty of systemic risk) and its limited applicability to fragmented governance landscapes (in the absence of an effective consideration of risk ownership).

After critically examining the suitability of the impact chain framework, a new protocol is introduced, which builds on principles for managing complex risk and frameworks for assessing risk ownership. The protocol is designed to enable case-study researchers to better identify, assess, and appraise transboundary climate risks, as well as enquire into appropriate risk owners and adaptation options across scales. The paper argues for more innovation in adaptation research to better reflect the complexity and interdependency that characterize today’s world.

This work aims to demonstrate why the transboundary nature of climate risk requires a distinct analytical approach and proposes a seven-step guide that aims to facilitate the exploration of transboundary climate risk through case-study-based research for adaptation.

Domestic climate risks continue to dominate the field of climate change research, translating into a significant blind spot in adaptation planning and action. Without the provision of practical guidance — to equip researchers with approaches and tools specifically designed to analyze the transboundary and systemic nature of climate risk — adaptation action will fail to offer sufficient protection against the full range of risks climate change presents.

This article begins to address this void and ultimately — through greater recognition and understanding of transboundary climate risk — promote approaches to adaptation that are reflective of the interdependency of our world today and our shared and common future.