This record describes Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2025_V02, titled: "Multiyear: Integrated Marine Observing System (IMOS) Southern Ocean Time Series (SOTS) Strategic Partnership." The voyage took place between March 26, 2025 and April 14, 2025 (AEST), departing from Hobart and returning to Hobart. Water samples collected during the voyage were analysed in the ship’s hydrochemistry laboratory for nutrients, dissolved oxygen, and salinity. No significant sample collection, analysis, or data processing issues were encountered for reporting. Five nutrients were determined: silicate, phosphate, nitrate + nitrite, nitrite and ammonium using a Seal AA3 autoanalyser. Certified reference materials for nutrients in seawater (RMNS) were within certified expanded uncertainty. Missing and suspect hydrology samples are listed in Appendix, Missing or Suspect Nutrient Data. For more information please refer to the Data Processing Report linked below. 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2022_V03, titled: "SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania." The voyage took place between May 4 and May 15, 2022, departing from Hobart (TAS) and returning to Hobart. 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator Voyage IN2021_V02, titled "SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania." The voyage took place between April 14 and April 28, 2021 departing from Hobart (TAS) and arriving in Hobart. Water samples collected during the voyage were assayed in the ship’s hydrochemistry laboratory for nutrients, dissolved oxygen, and salinity. The samples came from deployments of the CTD rosette, underway system, and from experiments run by the science party. Five nutrients were analysed; silicate, phosphate, nitrate + nitrite, nitrite and ammonium. Certified reference materials for nutrients in seawater were within the specified limits of the certified value. This dataset has been 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2024_V02, titled: "SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania" The voyage took place between March 31 to April 19, 2024, departing from Hobart (TAS) and returning to Hobart. 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage: IN2022_V08, titled "Biodiversity Assessment of Australia’s Indian Ocean Territories." The voyage took place between September 30, 2022 (ACST) and November 3, 2022 (AWST), departing from Darwin 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2024_T01, titled: "Freemantle to Hobart, 2024 Transit". The voyage took place between 9 March 2024 and 20 March 2024, departing from Freemantle (WA) and returning to Hobart (TAS). 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2019_V03, titled: "A coupled bio-physical, ecosystem-scale, examination of Australia’s International Indian Ocean Expedition line 110E." The voyage took place from Fremantle (WA) to Fremantle between May 14 and June 14, 2019. 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 archived at the CSIRO O&A 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2021_V04, titled: "Biodiversity Assessment of Australia’s Indian Ocean Territories." The voyage took place between June 30 and July 29, 2021 departing from Darwin (NT) and arriving in Hobart (TAS). Water samples collected during the voyage were analysed in the ship’s hydrochemistry laboratory for nutrients, dissolved oxygen, and salinity. Five nutrients were determined: silicate (Si(OH)4), phosphate (PO4), nitrate + nitrite (NOx), nitrite (NO2) and ammonium (NH4). Certified reference materials for nutrients in seawater (RMNS) were within 3% of their certified values. See table for the CTD deployment versus measured RMNS values. Final hydrology data, analytical methods, related log sheets and processing notes can be obtained from the CSIRO data centre. This dataset has been 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) 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. 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 Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2023_E01, titled: "Sea Trials e01." The voyage took place between 7 to 14 January, 2023, departing from Fremantle (WA) 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.