The New Zealand Tsunami Database: Historical and Modern Records

A database of historical (preinstrumental) and modern (instrumentally recorded) tsunamis that have impacted or been observed in New Zealand has been compiled and published online. New Zealand's tectonic setting, astride an obliquely convergent tectonic boundary on the Pacific Rim, means that it is vulnerable to local, regional, and circum-Pacific tsunamis. Despite New Zealand's comparatively short written historical record of about 200 years, there is a wealth of information about the impact of past tsunamis. The New Zealand Tsunami Database (NZTD) currently has 800+ entries that describe > 50 high-validity tsunamis. Sources of historical information include witness reports recorded in diaries, notes, newspapers, books, and photographs. Information on recent events comes from tide gauges and other instrumental recordings such as Deep-ocean Assessment and Reporting of Tsunamis (DART) buoys, and media of greater variety, for example, video and online surveys. The NZTD is an ongoing project with information added as further historical records come to light. Modern tsunamis are also added to the database once the relevant data for an event have been collated and edited. This article briefly overviews the procedures and tools used in the recording and analysis of New Zealand's historical tsunamis, with emphasis on database content.