This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility 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). Data for 25 deployments were acquired using the Sea-Bird SBE911 CTD 24, fitted with 31 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 0.0013062 PSU, within our target of ‘better than 0.002 PSU’. The standard product of 1 decibar binned averaged were produced using data from the primary sensors. The dissolved oxygen data calibration fit had a SD of 0.089089μM. The agreement between the CTD and bottle data was good. There was an observed spike in values indicating a blockage in the secondary sensors of CTD deployment 11 around 2700 decibar and it is recommended to use the primary sensor data. An Altimeter, Nephelometer, Transmissometer, CDOM, Fluorometer, and Turbidity meter were also installed on the auxiliary A/D channels of the CTD. The Seapoint nephelometer values were found to be out of the expected range for the sensor. The collected data were subsequently processed and archived within the CSIRO National Collections and Marine Infrastructure (NCMI) Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility 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 to July 29, 2022 departing from Brisbane (QLD) and returning to Brisbane. Data for 22 CTD deployments were acquired using the Sea-Bird SBE911 CTD 24, 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. Issues with the primary and secondary conductivity sensors were observed in the first 3 casts of the CTD deployment. To resolve these issues, the primary and secondary conductivity sensors were replaced. Subsequently, casts 4-22 were treated as a different deployment group. Casts 5 and 6 were diagnostic casts. The final conductivity calibration was based on a two-deployment groupings. The final calibration from the primary sensor had a standard deviation (SD) of 0.0011575 PSU, and 0.001534 PSU respectively, well 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 calibration fit had a SD of 0.76684μM. The agreement between the CTD and bottle data was good. An Altimeter, PAR, Transmissometer, Fluorometer, and Turbidity sensor were also 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 Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2022_V08, titled: "Biodiversity Assessment of Australia’s Indian Ocean Territories." The voyage took place between September 30 and November 3, 2022 departing from Darwin (NT) and returning to Fremantle (WA). 44 CTD deployments were conducted on this voyage. The data were acquired with the CSIRO CTD unit #22 (S/N 1039), a Sea‐Bird SBE911 with dual conductivity and temperature sensors. The CTD was additionally fitted with SBE43 dissolved oxygen sensors including Altimeter, Nepthelometer, Transmissometer, CDOM, chlorophyll‐a, and Scattering. 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 Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2016_V06 titled: "Sustained monitoring of the EAC: mass, heat and freshwater". The voyage took place between 29 October and 13 November, 2016 departing from Brisbane (QLD) and arriving in Brisbane. Data for 12 deployments were acquired using the Seabird SBE911 CTD unit 20, fitted with 24 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 (S.D) of 0. 0013601 PSU, within our target of ‘better than 0.002 PSU’. The standard product of 1dbar binned averaged were produced using data from the primary sensors. The dissolved oxygen data calibration fit had a S.D. of 0. 84677 uM. The agreement between the CTD and bottle data was good. The Biospherical photosynthetically active radiation (PAR), C-Star transmissometer and the Wetlabs ECO chlorophyll and CDOM sensors were also installed on the auxiliary A/D channels of the CTD The collected data were subsequently processed and archived within the CSIRO Oceans and Atmosphere (O&A) Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2019_V07, titled "RAN Hydrographic and Maritime Heritage Surveys." The voyage took place from Hobart (TAS) to Hobart between April 11 and April 23, 2019. Data for 10 deployments were acquired using the Sea-Bird SBE911 CTD 23, 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. Casts 1, 2, and 3 were test casts to verify the recently serviced secondary altimeter data and no bottles were fired during those deployments. A Wetlabs CSTAR Transmissometer, Wetlabs CDOM Fluorometer, and PAR sensor were also installed on the auxiliary A/D channels of the CTD. The collected data were subsequently processed and archived within the CSIRO Oceans and Atmosphere (O&A) Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2016_V04, titled: "Influence of temperature and nutrient supply on the biogeochemical function and diversity of ocean microbes." The voyage took place between August 31 and September 22, 2016 departing from Sydney(NSW) and arriving in Brisbane (QLD). Data for 56 deployments were acquired using the Seabird SBE911 CTD 20, fitted with 24 ten-litre bottles on the rosette sampler. The Seabird SBE911 has dual conductivity and temperature sensors. The CTD was additionally fitted with SBE43 dissolved oxygen sensors, fluorometer, transmissometer, PAR sensor and LADCP sensors. These sensors are described in the processing report. The collected data was subsequently processed and archived within the CSIRO Oceans and Atmosphere (O&A) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2016_V05, titled: "The Great Barrier Reef as a significant source of climatically relevant aerosol particles." The voyage took place between September 28 and October 24, 2016 departing from Brisbane (QLD) and arriving in Brisbane. Data for 62 deployments were acquired using the Seabird SBE911 CTD 21 and CTD 20, fitted with 24 twelve-litre bottles on the rosette sampler. Seabird-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 0.0014061 PSU, well within our target of ‘better than 0.002 PSU.’ The standard product of 1 dBar-binned averages were produced using data from the primary sensors. The dissolved oxygen data calibration fit had a SD of 0.67142 µM. The agreement between the CTD and bottle data was good. Altimeter, Photosynthetically Active Radiation (PAR) sensor, Colored Dissolved Organic Matter (CDOM) sensor, Fluorometer, Transmissometer, Nephelometer, and Nitrate sensor were also installed on the auxiliary A/D channels of the CTD. The collected data were subsequently processed and archived within the CSIRO Oceans and Atmosphere (O&A) Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2018_T01 titled: "Physical and biogeochemical gradients in the East Australian Current." The voyage took place between April 6 and April 14, 2018 departing from Hobart (TAS) and arriving in Brisbane (QLD). Data for 21 deployments were acquired using the Sea-Bird SBE911 CTD 24, 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 Salinometer was found to have been malfunctioning and not reliably reporting results on IN2018_T01. The final conductivity calibration was based on calibrations derived on the subsequent voyage: IN2018_V03. The final calibration from the primary sensor had a standard deviation (SD) of 0.0013986 PSU for the primary and 0.0014150 PSU for the secondary, well within our target of ‘better than 0.002 PSU’. The standard product of 1 decibar binned averaged were produced using data from the primary sensors with secondary sensors included with the suffix ‘_2’. The dissolved oxygen data calibration fit had a SD of 0.70186 uM for the primary and 0.81698 uM for the secondary. The agreement between the CTD and bottle data was good. Fluorometer, Altimeter, Transmissometer and PAR sensors were also installed on the auxiliary A/D channels of the CTD. The collected data were subsequently processed and archived within the CSIRO Oceans and Atmosphere (O&A) Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2021_V03, titled: "Integrated Marine Observing System: monitoring of East Australian Current property transports at 27o S." The voyage took place between May 8 and June 3, 2021 departing from Hobart (TAS) and arriving in Brisbane (QLD). Data for 36 deployments were acquired using the Sea-Bird SBE911 CTD 24, fitted with 19 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 0.0019084 PSU, when rounded this is outside our target of ‘better than 0.002 PSU’, so the cut-off was adjusted to 0.003 PSU. The standard product of 1 decibar binned averaged were produced using data from the primary sensors. Cast 10 was ended prematurely so CapPro could not process cast properly. To overcome this, in MATLAB, the end of cast 9 was attached to the end of cast 10. This data will not appear in the raw files from SeaSave and should not affect processing, as CapPro will remove out of water data before processing but needs this data to find the end of the cast. During cast 12 the CTD landed on the bottom of the ocean floor, no damage was found, and all subsequent casts performed as expected. Prior to cast 31, due to some discrepancies between the primary and secondary sensors, the Seagoing Instrumentation Team swapped the secondary pump. This resolved the particular issue. Bottle seven had intermittent problems firing reliably. Initially the release magnet was swapped and all further casts had a backup fired with bottle 7, however it was later found that the root cause was corrosion under the epoxy. As a precaution, the whole trigger mechanism was swapped. The dissolved oxygen data calibration fit had a SD of 0.84461μM. The agreement between the CTD and bottle data was good. PAR, Transmissometer, CDOM, Altimeter and Ecotriplet were also installed on the auxiliary A/D channels of the CTD. The collected data were subsequently processed and archived within the CSIRO National Collections and Marine Infrastructure (NCMI) Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator Charter Voyage IN2015_C02 - Great Australian Bight (GAB) Deep water pelagic and benthic ecosystem study. The voyage is departing Port Lincoln on the 30th November, 2015 and arriving in Fremantle on the 22nd December, 2015. Data for 34 deployments were acquired using the Seabird SBE911 CTD 20, fitted with 36 ten 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. Chelsea fluorometer and Tritech altimeter were also installed on the auxiliary A/D channels of the CTD. These sensors are described in the processing report. The collected data was subsequently processed and archived within the CSIRO Oceans and Atmosphere (O&A) in Hobart. Additional information regarding this dataset may be contained in the Voyage Summary and the CTD Data Processing Report.