February 2, 1936 Tsunami: Goose Bay, South Island, New Zealand

On the night of 2-3 February 1936, a wave or waves occurred at Goose Bay, damaging one hut and smashing another, as well as damaging a parked car and depositing huge rocks well above HWM. The wave/s, which passed nearby to another cottage in which two people were sleeping, did not awaken them. The damage was attributed to one wave only probably occurring at high tide (which was just after midnight) or thereabouts, although the reason for assuming this was not recorded.

The waves occurred during one of the most damaging storms to strike New Zealand in the 20th century (Brenstrum, 1997) and at the same time as high spring tides at Kaikoura, which, according to NIWA Tide Forecaster, (http://www.niwa.co.nz/services/free/tides) are estimated to have been 0.07 m above MHWS. The storm crossed the North Island on 2 February, primarily affecting the North Island, but strong effects were also experienced on the northeast coast of the South Island. Hence, the conditions were conducive to the occurrence of storm surge, and storm waves. However, storm surge and storm waves alone would not be limited to a few waves and would affect a greater length of coastline over a longer time. As to why the damage at Goose Bay was attributed to one wave only rather than a series of storm waves is not known, but the strong pressure gradients associated with the storm may also have provided the right conditions for the occurrence of a few rogue waves or a meteo-tsunami, in which a short sequence of waves is possible.

Another explanation of the limited effect possibly lies in the occurrence of an offshore landslide. Just a few hundred metres offshore from Goose Bay is a submarine canyon, the extensive accumulated sediments at the top of which are considered capable of sliding into the canyon causing a large local tsunami at Goose Bay in particular (Walters et al. 2006). However, the coincidence of the inundation with severe weather conditions and high spring tide levels is too great to dismiss, and the inundation is attributed here to a meteo-tsunami or extreme storm waves and storm surge. (reference #5324)