This record describes multibeam echosounder data collected on RV Investigator voyage IN2024_V01, 'Multidisciplinary Investigations of the Southern Ocean' which departed Hobart on 05/01/2024 and returned to Fremantle on 05/03/2024. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter from Hobart, along the Antarctic ice edge to Fremantle. The EM710 MKII provides a 0.5° by 1° transmit and receive angular resolution respectively. The echosounder's nominal frequency range is from 40 to 100 kHz. Data are stored in *.all raw format for bathymetry and backscatter and *.wcd format for watercolumn backscatter at CSIRO. There are 135 files totalling 126.9 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. GPS tide was computed using the EGM2008 model and applied to the processed data. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry grids in geotiff format. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes SVP data collected on RV Investigator voyage IN2024_V01, 'Multidisciplinary Investigations of the Southern Ocean' which departed Hobart on 05/01/2024 and returned to Fremantle on 05/03/2024. A total of 131 SVP casts were conducted over the duration of this voyage. Data are stored in ASCII format files with extention *.000 at CSIRO. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes sub bottom profiler data collected on RV Investigator voyage IN2024_V01, 'Multidisciplinary Investigations of the Southern Ocean' which departed Hobart on 05/01/2024 and returned to Fremantle on 05/03/2024. The Kongsberg SBP120 (sub bottom profiler) was used to acquire data containing the specular reflections at different sediment interfaces below the seafloor from Hobart, along the Antarctic ice edge to Fremantle. The SBP120 provides a 3° by 3° angular resolution. The echosounder's frequency sweep range is from 2.5 to 7 kHz. The SBP120 was logged continuously for the extent of the voyage. Data are stored in *.raw and *.seg formats at CSIRO. There are 775 files totalling 29.8 GB of raw data in this dataset. The segy format data had a real time processing stream applied, which applies gain, a gain correction, matched filter with replica shaping, an attribute calculation for instantaneous amplitude and time variable gain. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request

This record describes XBT data collected on RV Investigator voyage IN2024_V01, 'Multidisciplinary Investigations of the Southern Ocean' which departed Hobart on 05/01/2024 and returned to Fremantle on 05/03/2024. A total of 109 XBT casts were conducted over the duration of this voyage. Data are stored in netCDF files at CSIRO. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes bioacoustic echosounder data collected on RV Investigator voyage IN2024_V01, 'Multidisciplinary Investigations of the Southern Ocean' which departed Hobart on 05/01/2024 and returned to Fremantle on 05/03/2024. The Simrad EK60 split beam echosounders for18kHz and Simrad EK80 split beam echosounders for 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 250-1500 m, from Hobart, along the Antarctic ice edge to Fremantle. All frequencies were logged continuously for the extent of the voyage. Some frequencyies were set to passive for periods of the voyage. Impedance issue Data are stored in *.raw, *.bot and *.idx format at CSIRO. There are 2,595 files totalling 249 GB of raw data in this dataset. No Processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2024_V01, 'Multidisciplinary Investigations of the Southern Ocean' which departed Hobart on 05/01/2024 and returned to Fremantle on 05/03/2024. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter from Hobart, along the Antarctic ice edge to Fremantle. The EM122 provides a 1 degree by 1 degree angular resolution. The echosounder's nominal frequency is 12 kHz. Data are stored in *.all raw format for bathymetry and backscatter and *.wcd format for watercolumn backscatter at CSIRO. There are 1,199 files totalling 150.8 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. GPS tide was computed using the EGM2008 model and applied to the processed data. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry grids in geotiff format. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes the Acoustic Doppler Current Profiler (ADCP) data collected from the Marine National Facility RV Investigator voyage IN2024_V01, titled: "Multidisciplinary Investigations of the Southern Ocean (MISO): linking physics, biogeochemistry, plankton, aerosols, clouds, and climate." The voyage took place between January 02, 2024 and March 05, 2024 (AEST), departing from Hobart and returning to Fremantle. Voyage was split into two as the drop keel location was moved without acquisition being stopped. WH75 was used for most of the voyage after OS75 stopped working on the 6th January. On the 23rd of February the WH75 failed, possibly due to water ingress into the cable. ADCP data were collected using the University of Hawaii Data Acquisition System (UHDAS) and post-processed using the Common Ocean Data Access System (CODAS). The RDI Ocean Surveyor OS150 and OS75 were run in narrowband mode (nb) and the RDI Ocean Surveyor WH75kHz ADCP was run in broadband mode (bb). Internal triggering was used. Both port and starboard drop keels are located approximately 6m below the water line, additionally both port and starboard keels were extended to: • 0.0m from the start of the voyage until 4th January 23:40 (part-1 of the voyage) • 1.2m thereafter until the end of the voyage (part-2 of the voyage) Resulting in 6.0m and 7.2m below the water line respectively. For more information please see the Processing Report (linked below). This dataset was processed (quality-controlled), and then archived by the CSIRO National Collections and Marine Infrastructure (NCMI) Information and Data Centre (IDC).

This record describes Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2024_V01, titled: "Multidisciplinary Investigations of the Southern Ocean (MISO): Linking Physics, Biochemistry, Plankton, Aerosols, Clouds and Climate." The voyage took place between January 02, 2024 and March 05, 2024 (AEST), departing from Hobart and returning to Fremantle. Hydrology samples were collected from Niskin bottles sampled at various depths during Conductivity-Temperature-Depth (CTD) deployments. Parameters analysed were salinity, dissolved oxygen, phosphate, silicate, nitrate plus nitrite and ammonium. This dataset has been processed (quality-controlled), and archived at the CSIRO National Collections and Marine Infrastructure (NCMI) Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset is contained in the Voyage Report and Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2024_V01, titled: "Multidisciplinary Investigations of the Southern Ocean (MISO): Linking Physics, Biochemistry, Plankton, Aerosols, Clouds, And Climate." The voyage took place between January 2 and March 5, 2024 departing from Hobart (TAS) and returning to Freemantle (WA) Data for 103 CTD deployments were acquired using the Sea-Bird SBE9+V2 CTD unit #24 (S/N 1354), fitted with 36 twelve-litre bottles on the rosette sampler. Sea-Bird-supplied calibration factors were used to compute the pressures and preliminary conductivity values. CSIRO-supplied calibrations were applied to the temperature data. The data were subjected to automated QC to remove spikes and out-of-range values. The final conductivity calibration was based on a single deployment grouping. The final calibration from the primary sensor had a standard deviation (SD) of 0.0012679 PSU, within our target of ‘better than 0.002 PSU’. The standard product of 1-decibar binned averages were produced using data from the primary sensors. The dissolved oxygen data (primary) calibration fit had a SD of 0.94146 (Casts: 1-52) and 0.94773 (Casts: 53-103) μM. The agreement between the CTD and bottle data was good. Additional sensors include: Altimeter (Tritech PA500), Transmissometer (Wetlabs C-Star ), CDOM, Chlorophyll-a, Scattering (Wetlabs ECO FLCDRTD) were installed on the auxiliary A/D channels of the CTD. The collected data were subsequently processed (quality-controlled), and archived by the CSIRO National Collections and Marine Infrastructure (NCMI) Information and Data Centre (IDC). Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the data (CTD, Dissolved Oxygen, Transmissometer, PAR, ECO Triplet, Nitrate, Fluorescence and LOPC) collected using the towed TRIAXUS platform on Investigator voyage IN2024_V01, titled: "Multidisciplinary Investigations of the Southern Ocean (MISO): linking physics, biogeochemistry, plankton, aerosols, clouds, and climate." The voyage took place between January 02, 2024 and March 05, 2024 (AEST), departing from Hobart and returning to Fremantle. The collected data were processed (quality-controlled), and subsequently archived by the CSIRO National Collections and Marine Infrastructure (NCMI) Information and Data Centre (IDC). Additional information regarding this dataset may be contained in the Voyage Summary and the Data Processing Report.