Tsunami science

Summary

This research models wave heights at coast, inundation depths and water velocities for Selwyn and southern Banks Peninsula for multiple regional and distant source tsunami scenarios, including 3m and 5m wave height at coast scenarios and 'worst case' scenarios up to 12m wave height at the coast.

The modelling shows that the largest threat for Selwyn and southern Banks Peninsula in terms of potential area inundated is a large regional-source tsunami from the Hikurangi subduction zone to the east of the North Island, followed by a large regional-source tsunami from the Puysegur subduction zone to the south of Fiordland, followed by large distant-source tsunamis from South America (Peru), Central America and the Kermadec subduction zone. There are no known significant local tsunami sources for this part of the Canterbury coast.

The primary purpose of the modelling was to delineate tsunami evacuation zones and inform public education and evacuation/response planning. The modelling assumes the largest tsunami wave arrives at high tide at the current sea level, and does not take into account different sea level rise scenarios.

Emergency management relevance

This research provides modelled inundation depths and water velocities for multiple tsunami scenarios for Selwyn and southern Banks Peninsula, and can be used for tsunami evacuation zones, evacuation and response planning, infrastructure planning, public education and some types of land use planning.

Additional information

Authors: Christof Mueller, Xiaoming Wang, Bilijana Lukovic

Date: 2020

Funders: Environment Canterbury

Format: GNS Science report

Reference: Mueller, C., Wang, X., Lukovic, B. (2020). Multiple scenario tsunami modelling for the Selwyn coastline, Kaitorete Barrier and Akaroa Harbour. GNS Science Consultancy Report 2020/47.