Tsunami science

Summary

This research models wave heights at coast, inundation depths and water velocities for northern Pegasus Bay and northern 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 northern Pegasus Bay and northern Banks Peninsula in terms of potential area inundated is a large distant-source tsunami from South America (Peru), followed by large regional-source tsunamis from the Kermadec and Hikurangi subduction zones to the east and north of the North Island and the Puysegur subduction zone to the south of Fiordland. Local-source tsunamis generated in Pegasus Bay created smaller waves than the distant and regional-source tsunamis.

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 northern Pegasus Bay and northern 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: Jean Roger, Christof Mueller, Xiaoming Wang

Date: 2020

Funders: Environment Canterbury

Format: GNS Science report

Reference: Mueller, C., Wang, X., Lukovic, B. (2020). Multiple scenario tsunami modelling for northern Pegasus Bay and northern Banks Peninsula Bays. GNS Science Consultancy Report 2020/136.