Digital Elevation Model of Jackson Bay, New Zealand

Purpose: numerical modelling of tsunami For the purpose of studying the impact of the 15 July 2009 Dusky Sound tsunami in the southwest of New Zealand South Island, a high-resolution digital elevation model (DEM) of Jackson bay, including the location of the tsunami gauge (Jack), has been built using three different types of data. They include: - NZ 8m Digital Elevation Model (LINZ, 2023) - Sounding points (Hydro, 1:22k - 1:90k, LINZ 2023), - Digitized and georeferenced nautical chart of Abut Head to Milford Sound/Piopiotahi (LINZ 2023). The data showing the highest resolution has been kept in priority. The depth values in the sounding points datasets are vertically referred to LAT (Lowest Astronomical Tide). For tsunami modelling purposes, all bathymetric and topographic data must be referenced to the same known vertical reference (e.g., Mean Sea Level or MSL). To standardize the datasets, we apply a vertical correction of MSL-LAT which in this case equals -1.2 m (Standard port tidal levels provided by LINZ[1]). We consider that the 8 m resolution DEM from LINZ (2023) is referenced to MSL. The compilation of data has been interpolated to a regular spatial resolution 0.0001° (~10 m). The data interpolation processes have been done using the kriging interpolation method. For more information about this method, see for example Oliver and Webster (1990). [1] https://www.linz.govt.nz/guidance/marine-information/tide-prediction-guidance/standard-port-tidal-levels