Burbidge DR, Dunant A, Moratalla J, Sadashiva VK, Uma SR, Christophersen A. 2021. Cascading hazard and risk framework for Hikurangi Flagship project. Lower Hutt (NZ): GNS Science. 54 p. (GNS Science report; 2021/13). doi:10.21420/40KM-BY60.
Abstract
The purpose of this report is to review existing and emerging options to create a framework to calculate the total probabilistic risk faced by New Zealand from arthquakes on the Hikurangi Subduction Zone (HSZ) including their cascading effects. The work underpins the End-to-End Flagship project within the Strategic Science Investment Fund (SSIF) Hazard and Risk Mitigation (HRM) programme at GNS Science. The primary challenge of calculating the total probabilistic risk of subduction earthquakes problem is to efficiently, but as comprehensively as possible, include all the interactions between the various perils that could be triggered by an earthquake (e.g. strong ground shaking, landslides, tsunami, fire and liquefaction) and the cumulative and cascading effects of multiple perils on buildings and other infrastructure. We conclude that probabilistic graphical methods such as Bayesian Networks or Multi-hazard Network Simulations (MNS) are the most promising frameworks to use for all, or part, of this problem. One advantage of MNS is that it is likely to be easier to integrate the output with GNS Science’s risk model, Riskscape. The next step in the project is to undertake a small case study to further explore the different methods and to help determine their pros and cons before conducting a full probabilistic earthquake risk assessment for earthquakes on the HSZ interface and their cascading effects on New Zealand. (auth)
