This record describes multibeam echosounder data collected on RV Investigator voyage IN2018_V04, 'Constraining external iron inputs and cycling in the southern extension of the East Australian Current' which departed Hobart on the 11 September 2018 and returned to Hobart on the 8 October 2018. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter data. 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 23 files totalling 11.1 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. Tide corrections [were/were not] applied to the processed data. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter 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 multibeam echosounder data collected on RV Investigator voyage IN2022_V06, titled "Integrated Marine Observing System: monitoring of East Australian Current property transports at 27 degrees South." The voyage took place between July 14 and July 30, 2022 (AEST), departing from Brisbane and returning to Brisbane. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn around Brisbane 27 degrees South. 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 91 files totalling 28.0 GB of *.all raw data and 90 files totalling 112.0 GB of *.wcd 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 corrections were applied to processed data. Calculations are based on the Applanix PosMV Marinestar G4+ Ellipsoidal heights. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter 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 multibeam echosounder data collected on RV Investigator voyage IN2023_V06, titled: "Understanding Eddy Interactions and Their Impacts In the East Australian Current System." The voyage took place between October 9 and November 2, 2023, departing from Sydney (NSW) and returning to Sydney. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter around NSW coastal areas. 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 18 files totalling 2.29 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 ME 70 scientific multibeam fisheries echosounder data collected on RV Investigator voyage IN2018_V04, 'Constraining external iron inputs and cycling in the southern extension of the East Australian Current' which departed Hobart on the 11 September 2018 and returned to Hobart on the 8 October 2018. The Simrad ME70 scientific multibeam echosounder acquired acoustic backscatter data. The echosounder's frequency range is from 70 kHz to 120 kHz. The ME70 was run for a short period on Station 3. It was not logged continuously due to the deep water depths and interference with the EK60 data. Data are stored in Simrad *.all raw format at CSIRO. There are 108 files totalling 10.4 GB of raw data in this dataset. No processing has been conducted on this data. Additional information regarding this dataset, including the settings used, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2018_V04, 'Constraining external iron inputs and cycling in the southern extension of the East Australian Current' which departed Hobart on the 11 September 2018 and returned to Hobart on the 8 October 2018. The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m in deep water. All frequencies were logged for the extent of the voyage. Data are stored in *.raw, *.bot and *.idx format at CSIRO. There are 897 files totalling 84.8 GB of raw data in this dataset. 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 gravity data collected on RV Investigator voyage IN2018_V04, 'Constraining external iron inputs and cycling in the southern extension of the East Australian Current' which departed Hobart on the 11 September 2018 and returned to Hobart on the 8 October 2018. The gravity meter instrument is a MicroG Lacoste Air-Sea II. Data are stored in .ENV and .DAT data files at CSIRO. There are 25 files totalling 375 MB of raw data in this dataset. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes sub bottom profiler data collected on RV Investigator voyage, IN2018_V04, 'Constraining external iron inputs and cycling in the southern extension of the East Australian Current' which departed Hobart on the 11 September 2018 and returned to Hobart on the 8 October 2018. The Kongsberg SBP120 (sub bottom profiler) was used to acquire data containing the specular reflections at different sediment interfaces below the seafloor. 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 for the extent of the voyage. Data are stored in *.raw (150 files 6.2 GB) raw and *.seg (145 files 6.03 GB) segy formats at CSIRO. 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 the Acoustic Doppler Current Profiler (ADCP) data collected from the Marine National Facility RV Investigator voyage IN2019_V05, titled: "Integrated Marine Observing System: monitoring of East Australian Current property transports at 27 degrees South." The voyage took place between September 9 and September 29, 2019 departing from Brisbane (QLD) and arriving in Brisbane. Data was collected for the duration of the voyage using UHDAS, and post-processed using CODAS. Both the RDI Ocean Surveyor 150kHz ADCP and the RDI Ocean Surveyor 75kHz ADCP were run in narrowband. Internal triggering was used. The drop keel was at 2m below the waterline for the duration of the voyage. See the voyage computing and electronics report for more details regarding data acquisition. This dataset was processed and then archived within the CSIRO Oceans and Atmosphere (O&A) Information and Data Centre (IDC) in Hobart.

This record describes the Acoustic Doppler Current Profiler (ADCP) data collected from the Marine National Facility RV Investigator voyage IN2018_V03, titled: "Integrated Marine Observing System: monitoring of East Australian Current property transports at 27oS." The voyage took place between April 19 and May 10, 2018 departing Brisbane (QLD) and returning to Brisbane. Data was collected during in2018_v03 for the entire voyage. Data was collected using UHDAS and post-processed using CODAS. The os150(150kHz) ADCP was not operational during this voyage and was replaced with a wh150(150kHZ). The wh150 was calibrated in the preceding transit. The 75khz ADCP was operated in narrowband mode with 8m bins for the duration of the voyage. Internal triggering was used as external triggering was found to be unstable on previous voyages. The drop keel was at 4m for most of the voyage but raised to 2m during periods of rough weather. Acquisition was stopped and started upon a keel depth change to ensure no data was corrupted. See the voyage computing and electronics report for more details regarding data acquisition. This dataset was processed and then archived within the CSIRO Oceans and Atmosphere (O&A) Information and Data Centre (IDC) in Hobart.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2018_V04, 'Constraining external iron inputs and cycling in the southern extension of the East Australian Current' which departed Hobart on the 11 September 2018 and returned to HObart on the 8 October 2018. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter. 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 574 files totalling 51.5 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. Tide corrections were not applied to the processed data. Processed data had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.