IN2020_V08 Southern Ocean Bathymetry 10m - 210m Multi-resolution AusSeabed products

This layer group describes multibeam echosounder data collected on RV Investigator voyage IN2020_V08 titled "SOLACE - Southern Ocean Large Areal Carbon Export: quantifying carbon sequestration in subpolar and polar waters". The voyage took place between December 5, 2020 and January 16, 2021, departing from Hobart (TAS) and arriving in Hobart (TAS).\n\nThe purpose of this voyage was to meet the following aims of the Southern Ocean Large Areal Carbon Export (SOLACE) project:\nFirst, to improve water column measurement of the downward export flux of carbon of the biological pump using an integrated suite of new technological advances – from particle decomposition to mesopelagic vertical migrations.\n\nSecond, to integrate these improved estimates of the functioning of the biological export with biooptical properties, used as proxies of biogeochemical (BGC) properties, and which can be remotely sensed using satellite sensors. A combination of conventional passive “ocean colour radiometry” and active “CALIOP” LIDAR (that ‘sees through clouds’ and also senses below the surface) will be validated on SOLACE to provide a comprehensive regional extrapolation of carbon export fluxes.\n\nThird, to cross-link larger scale estimates of the biological pump (termed the BGP – biological gravitational pump - in a Review paper at Nature by Boyd, Claustre, Levy, Siegel and Weber, under revision) with those of PIPs (Particle Injection Pumps, Boyd et al., 2019, Nature) such as the Mixed Layer Pump (Llort et al., 2018) than can be assessed using profiling biological-floats (i.e., BGC-ARGO) as part of the US S. Ocean SOCCOM mission (www.soccom.edu), as well as the individual programmes of France, Australia and others.\n\nFourth, to link these S. Ocean findings with those of international programmes on this topic, working on N. Hemisphere analogues, via data synthesis and modelling (co-collaborator Dave Siegel, UCSB) to produce large areal maps of carbon export by both the BGP and PIPs. These programmes sit under the JETZON umbrella - http://jetzon.org/ .\n\nThis dataset is published with the permission of CSIRO. Not to be used for navigational purposes.\n\nThe dataset contains bathymetry grids of 10m to 210m resolution of the Southern Ocean produced from the processed EM122 and EM710 bathymetry data.\nLineage: Multibeam data was logged from the EM’s in Kongsberg’s proprietary *.all format and was converted to be processed within Qimera 2.3.1. A Qimera project was created using the WGS 84 / World Mercator + EGM2008 (6893) coordinate\nsystem.\nOnce the raw files were converted into .qpd format a dynamic surface was created and the data was analysed for noise. Any noise was cleaned manually using the swath and 3D editors. All multibeam data was processed to “MSL” using the EGM2008 geoid via the RTK vertical referencing method.\n\nGSF files were exported out of Qimera and imported into Caris v11.3 to create .csar Cube surfaces. Csar surfaces were created for the transit at 200m for the EM122 and 10m for the EM710. Additional surfaces over areas of interest have been created at various resolutions.\n\nThe 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.