Aotearoa-New Zealand’s (A-NZ) caldera volcanoes, located within the Taupō Volcanic Zone (TVZ) in the central North Island, have typically been characterised as a low probability, high consequence risk. These volcanoes are capable of a broad and complex range of geophysical activity creating multiple hazards of variable intensity, both spatially and temporally. These can have diverse, complex, and potentially severe impacts on society. Equally, the societal responses to such impacts, both potential and actual, can be just as diverse and driven by a complex variety of factors across social, cultural, economic, built, and natural environments – also spatially and temporally sensitive.

One important tool for disaster risk management is the development of scenarios, which can be used to illustrate one (of many) potential outcome(s) of a complex and highly variable system. By determining fixed values on otherwise uncertain inputs, it allows easier understanding of how a complete caldera unrest and/or eruption may unfold. The use of scenarios, built from a common framework, can allow exploration of the diversity of potential outcomes from the complex volcanic system that is the TVZ. This common framework, in turn, partially addresses a key limitation of the approach.

More recently, collaborative development of scenarios, jointly by scientists, practitioners and representatives for the community, has been used to create products which are both ‘credible’ (informed by robust scientific knowledge) and ‘relevant’ (useful and useable for end-users), and so can be considered ‘legitimate’ – where the scenarios reflect the various stakeholders’ different values and priorities, and are ideally trusted by all and fit-for-purpose.

The aim of this thesis is to develop a modular, adaptable framework for the development of scenarios to underpin the management of A-NZ’s caldera volcanic hazard risk within the ECLIPSE programme. This involves addressing the following objectives;

1. Identify and understand the hazards associated with silicic volcanoes in the Taupō Volcanic Zone.
2. Develop methods for disaster hazard and impact scenario development for silicic volcanism.
3. Evaluate the ECLIPSE Scenario Framework and ECLIPSE Scenarios through stakeholder engagement.

To achieve these objectives, an extensive literature review was undertaken to identify the hazards associated with caldera volcanoes in the TVZ and to identify potential methods for the development of volcanic scenarios. An inclusive co-production method was then used to identify and engage with key stakeholders, identify their respective requirements, and tailor the ECLIPSE Scenario Framework and ECLIPSE Scenarios to meet these requirements. Finally, the framework and scenarios were then evaluated in one-on-one interviews with stakeholders to assess the usefulness and useability of the framework and scenarios within the ECLIPSE community and the wider disaster risk management community.

The engagement workshops and interviews highlighted that the ECLIPSE Scenario Framework provided a useful foundation for combining cross boundary wants and needs from various stakeholder groups. Stakeholders stated that the ECLIPSE Scenario Framework (and ECLIPSE Scenarios) had given them a tangible output to structure discussions around caldera risk management from. They also stated it had provided guidance on where research should continue to develop in future, by highlighting research gaps – such as more in-depth social, cultural, and economic attributes and narratives within the ECLIPSE Scenario Framework and ECLIPSE Scenarios.

In summary, this thesis:

• Presents the first iteration of the ECLIPSE Scenario Framework – a framework for hazard and impact scenario development for silicic volcanoes in A-NZ.
• Presents two pillar scenarios developed from the ECLIPSE Scenario Framework as examples of how the framework can be used and what it can produce – ECLIPSE Scenario A: Taupō Unrest Scenario and ECLIPSE Scenario B: Taupō Eruption Scenario.
• Outlines a transparent, robust, co-production methodology for developing volcanic scenarios within A-NZ’s caldera volcano risk management community.
• Provides recommendations for future development of caldera scenarios using the ECLIPSE Scenario Framework within both the ECLIPSE programme and the wider volcanic risk management community