IN2023_V04 Southern Ocean Bathymetry 10m - 210m Multi-resolution AusSeabed products

Brief description

This layer group describes multibeam echosounder data collected on RV Investigator voyage IN2023_V04 titled "International nutrient inter-comparison study in the Southern Ocean: quantifying and identifying the causes of differences in dissolved inorganic nutrient datasets between global seagoing laboratories - Phase 2". The voyage took place between June 5 and June 19, 2023, departing from Hobart (TAS) and arriving in Hobart (TAS).

The purpose of this voyage was to conduct INIV 2023 phase 2 of the international inter-comparison voyage previously conducted by CSIRO in 2017.

This dataset is published with the permission of CSIRO. Not to be used for navigational purposes.

The dataset contains bathymetry grids of 10m to 210m resolution of the Southern Ocean produced from the processed EM122 and EM710 bathymetry data.
Lineage: Multibeam data was logged from the EM’s in Kongsberg’s proprietary *.all format and was converted to be processed within CARIS HIPS and SIPS version 11.4.18. Data were imported into the HIPS project using EM Height and the vessel file appropriate for either the EM122 or EM710. GPS tide was computed using the EGM2008 model EGM_2008_1Min_Aust_WGS84.csar. TPU values were computed using Measured Sound Velocity = 0.5 and Surface Sound Velocity = 0.2. The raw files were analysed for noise and cleaned manually. The data was then gridded at the highest resolution possible and further inspected for outliers.

The data was then gridded at multiple resolutions in python Caris batch script using a Depth filter Vs Resolution guideline derived from AusSeabed Multibeam guidelines v2 and further inspected for outliers. Final raster products are available in L3 folder of this collection. Final processed data were also exported per line as GSF and ASCII format and available in the L2 folder of this collection.