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 IN2019_V03, titled: "A coupled bio-physical, ecosystem-scale, examination of Australia’s International Indian Ocean Expedition line." The voyage took place between May 14 and June 14, 2019 departing from Fremantle (WA) and arriving in Fremantle. Data for 3 Triaxus deployments were acquired using seabirds SeaSave acquisition software with Seabird SBE911+ CTD #23. Sea-Bird and O&A Calibration lab supplied calibration factors were used to compute the pressure, preliminary conductivity, oxygen and temperature values. The data was subjected to automated QC to remove spikes and out-of-range values. Dissolved oxygen sensors, Photosynthetically Active Radiation (PAR) sensors were also installed on the auxiliary A/D channels of the CTD. In addition to the auxiliary channels an ECO Triplet and LOPC were mounted on the Triaxus as attached payloads. The standard data product (1 decibar/10 second binned averaged) was produced using data from the primary and seconday sensors to produce an along-track time-series dataset for each data scan file. These files were grouped into sections/legs containing the Triaxus deployment. Moreover, for each section, vertical casts were created with interpolated values from the along-track time-series binned dataset with a maximum interpolation distance of 1 cast. These generated the along-track and vertical cast section data products for each Triaxus deployment. Throughout the voyage there were some issues with the Triaxus deployments. As a result, the standard data products could not be made for every deployment. See the Processing Report for further details. The collected data were subsequently 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 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.

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 IN2016_V05, titled: "The Great Barrier Reef as a significant source of climatically relevant aerosol particles." The voyage took place between September 26 and October 24, 2016 departing from Brisbane (QLD) and arriving in Brisbane. CTD, Dissolved oxygen sensors, Transmissometer, Nephelometer and Cosine Photosynthetically Active Radiation (PAR) sensor were also installed on the auxiliary A/D channels of the CTD. In addition to the auxiliary channels, ECO Triplet, Nitrate, Fluorescence and LOPC were mounted on the Triaxus as attached payloads. The standard data product (1 decibar/10 second binned averaged) was produced using data from the primary sensors to produce an along-track time-series dataset for each CAP deployment. These deployments were grouped into legs, each containing a section of the Triaxus deployment and in each leg, vertical casts were created with interpolated values from the along-track time-series binned dataset with a maximum interpolation distance of 3 casts. These generated the along-track and vertical cast section data products for each Triaxus deployment. The collected data have been 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 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 IN2017_V02, titled: "SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania." The voyage took place between March 17 and March 28, 2017 departing from Hobart (TAS) and arriving in Hobart. CTD, Dissolved Oxygen, Transmissometer, PAR, and ECO Triplet have been processed and are made available via the links below. 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 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 IN2020_V08, titled: "SOLACE - Southern Ocean Large Areal Carbon Export: quantifying carbon sequestration in subpolar and polar waters." The voyage took place between December 4, 2020 and January 15, 2021 departing from Hobart (TAS) and arriving in Hobart. Eight Triaxus tows were undertaken. Tows 1 to 7 were to investigate oceanographic and biological features of interest to the Southern Ocean Large Areal Carbon Export project. The eighth tow was to compare to altimetry satellite data. Pressure, conductivity, temperature, and dissolved oxygen data were gathered from duplicate sensors using a Seabird SBE9+ CTD. Also carried on the Triaxus hull were a cosine Photosynthetically Active Radiation (PAR) sensor, a transmissometer, an eco-triplet (optical backscatter, CDOM fluorometer and chlorophyll fluorometer), a Laser Optical Plankton Counter (LOPC), and a user-provided Fluorescence Induction and Relaxation (FIRe) system. On each tow, only data from sections where the Triaxus was undulating regularly were processed. Data from deployment, turns and retrieval were gathered but not further processed. Pressure, conductivity, temperature, and dissolved oxygen sensor data were converted to calibrated units. Spikes and out-of-range values were removed and primary to secondary sensor data compared. Similarly PAR, transmissometer, and eco-triplet data were combined into the dataset. Both LOPC and FIRe data were gathered but are not processed or published in this report. Published data have been grouped into 1 decibar bins. Data from the primary sensors were assessed to be more reliable. On this voyage all tows were made up of sections that were sufficiently short to be recorded in single files. The published data consist of: • along-track time-series data for each section • synthetic interpolated vertical casts data for each undulation peak and trough of each section • interpolated sectional plots of various taken from along-track time-series data The collected data were subsequently 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 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 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, 2022 and May 15, 2022 (AEST), departing from Hobart and returning to Hobart. Data for one Triaxus tow were acquired using Seabird’s Seasave acquisition software using the Seabird SBE911+ CTD #25. Sea-Bird and O&A Calibration lab supplied calibration factors were used to compute the pressure, preliminary conductivity, oxygen, and temperature values. The data was subjected to automated QC to remove spikes and out-of-range values. A PAR, transmissometer, and SUNA sensors were also installed on the auxiliary A/D channels of the CTD. In addition to the auxiliary channels an ECO Triplet and LOPC were mounted on the Triaxus as attached payloads. A load cell sensor was also attached to the Triaxus mechanical termination. The standard data product (1 decibar/10 second binned averaged) was produced using data from the secondary sensors to produce an along-track time-series dataset for each data recording file. These files were grouped into sections containing each Triaxus tow and in each tow, vertical casts were created with interpolated values from the along-track time-series binned dataset with a maximum interpolation distance of 1 cast/undulation. These generated the along-track and vertical cast section data products for each Triaxus tow. An issue was identified at the start of deployment once the Triaxus was in water and the pumps switched on, where the salinity values were in significant disagreement and both showing unrealistic readings. It was determined that the connectors for the primary and secondary conductivity sensors had been swapped. This was corrected without recovery and redeployment of the Triaxus by swapping the calibration parameters. Further manual manipulation of the data was required during post-processing to match the physically co-located sensors for correct salinity and oxygen value calculations. 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.

This record describes the data (CTD, Dissolved Oxygen, Transmissometer, PAR, ECO Triplet, Nitrate and LOPC) collected using the towed TRIAXUS platform on Investigator voyage IN2016_V01, titled: "HEOBI – Heard Earth-Ocean-Biosphere Interactions." The voyage took place between January 8 and February 27, 2016 departing from Fremantle (WA) and arriving in Hobart (TAS). CTD, Dissolved Oxygen, Transmissometer, PAR, and ECO Triplet have been processed and are made available via the links below. 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 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 IN2015_V01, titled: "IMOS Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania." The voyage took place between March 21 and March 30, 2015 departing from Hobart (TAS) and arriving in Hobart. CTD, Dissolved Oxygen, Transmissometer, PAR, and ECO Triplet have been processed and are made available via the links below. 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 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 IN2023_V07, titled: "SWOT-ACC: smaller scales of the Antarctic Circumpolar Current in a meander south of Tasmania." The voyage took place between November 15, 2023 and December 20, 2023 (AEST), departing from Hobart and returning to Hobart. The primary focus of this voyage was to enhance our ability to observe and comprehend the effects of small-scale motions (ranging from 10 to 100 km) on the dynamics of the Antarctic Circumpolar Current (ACC). The groundbreaking Surface Water Ocean Topography (SWOT) satellite mission will provide unprecedented measurements of sea surface height over a wide area with substantially improved spatial resolution compared to traditional altimeters. While SWOT will offer unparalleled coverage in both space and time, it is crucial to obtain in situ subsurface ocean measurements to validate the satellite observations and establish the connection between small-scale variability in sea surface height and subsurface ocean circulation and dynamics. The objective was to gather comprehensive multidisciplinary measurements along a swath traversing a standing meander of the ACC. This meander represents a region of intense eddy activity, cross-front exchange, and vibrant small-scale motions. The experiment's goals encompass characterizing the small-scale variability within this meander, establishing a correlation between small-scale variations in sea surface height and subsurface ocean structure, quantifying the contribution of small-scale processes in facilitating the transport of heat and carbon across the ACC, and investigating the interconnectedness of physical, biogeochemical, and biological processes at small spatial and temporal scales. 5 Triaxus tows were conducted. Pressure, conductivity, temperature, and dissolved oxygen data were gathered from duplicate sensors using a Seabird SBE9plus CTD. Also carried on the Triaxus hull were a cosine Photosynthetically Active Radiation (PAR) sensor, a transmissometer, an ECO Triplet (optical backscatter, CDOM fluorometer and chlorophyll fluorometer), a Laser Optical Plankton Counter (LOPC) and SUNA nitrate sensor. Triaxus hull number 2 was utilized throughout the entire voyage, completing 5 tows with a total towing time of 121.75 hours. The vehicle was generally towed between 5-7 knots depending on the conditions. Overall, it performed well during the entire voyage. The following issues were encountered: • There were 5 instances (Tow1) when the Triaxus software crashing and Seasave stopping. Fortunately, after multiple restarts, it returned to normal operation once payloads and undulations were reset. Additionally, on two occasions, the software failed to maintain the designated undulation schedule and required a restart to execute undulations correctly. • During tow #3, halfway through, the secondary DO sensor #3534 was replaced with #1794. The DOs were in specification however this brought the reading closer together. During the beginning of Tow 3, the Suna data for Triaxus was not displaying on Grafana, leg-2 was thus aborted. • On several of the tows, the fairing became loose from the cable and thrashed in the current. Eventually, the method outlined in IN2023_V06 for securing the fairing was adopted. This involved using regular-sized cable ties and hose clamps spaced approximately 300mm apart along the fairing to keep it securely attached to the sea cable. • During Triaxus tow 4 on December 5th a malware attack was encountered, corrupting the network share drive containing CTD data. The tow was promptly aborted at 0830 UTC, and the vehicle was safely recovered without incident. For more detailed information on the malware attack, please refer to the DAP report. On each tow only data from legs where the Triaxus was vertically undulating regularly were processed. Data from

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 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 for 6 Triaxus deployments were acquired using Seabird’s Seasave acquisition software using the Seabird SBE911+ CTD 23. O&A Calibration lab supplied calibration factors were used to compute the pressure, preliminary conductivity, oxygen and temperature values. The data was subjected to automated QC to remove spikes and out-of-range values. A Biospherical QCP2300-HP PAR, and a WetLabs C-STAR Transmissometer sensors were also installed on the auxiliary A/D channels of the CTD. In addition to the auxiliary channels an ECO Triplet and LOPC were mounted on the Triaxus as attached payloads. The standard data product (1 decibar/10 second binned averaged) was produced using data from the primary sensors to produce an along-track time-series dataset for each data recording file. These files were grouped into sections containing each Triaxus deployment and in each deployment, vertical casts were created with interpolated values from the along-track time-series binned dataset with a maximum interpolation distance of 1 cast. These generated the along-track and vertical cast section data products for each Triaxus deployment. All deployments except for 3 were along the mooring line transect. Throughout the voyage there were some issues with the Triaxus vehicle. Communication loss with the Triaxus ended Deployment 1 early, requiring re-termination. Deployment 5 also suffered communication loss, ending acquisition early. The Primary SBE43 Oxygen sensor was swapped out after deployment 3 due to increased noise in sensor readings. The collected data were subsequently 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 Data Processing Report.