This record describes gravity data collected on RV Investigator voyage IN2019_V06, titled 'Tropical observations of atmospheric convection, biogenic emissions, ocean mixing, and processes generating intra-seasonal SST variability' which departed Darwin on the 19th of October 2019 and returned to Darwin on the 17th of December 2019 ,consisting of two legs. Leg 1 - Darwin, 20:00, 19 October 2019 to Darwin, 19:00, 10 November 2019 Leg 2 - Darwin, 20:00, 11 November 2019 to Darwin, 08:00, 17 December 2019 The gravity meter instrument is a MicroG Lacoste Air-Sea II. Data are stored in .ENV and .DAT data files at CSIRO. There are 44 files totalling 392 MB of raw data in this dataset for Leg 1. There are 88 files totalling 680 MB of raw data in this dataset for Leg 2. Wharf tie[s] were undertaken upon returning to Darwin on gravity station 1991980532: Stokes Wharf West, using a Scintrex Autograv CG-5. Wharf tie data can be found in T011050.TXT, which is stored with the raw data. No processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2019_V06, titled 'Tropical observations of atmospheric convection, biogenic emissions, ocean mixing, and processes generating intra-seasonal SST variability' which departed Darwin on the 19th of October 2019 and returned to Darwin on the 17th of December 2019 ,consisting of two legs. Leg 1 - Darwin, 20:00, 19 October 2019 to Darwin, 19:00, 10 November 2019 Leg 2 - Darwin, 20:00, 11 November 2019 to Darwin, 08:00, 17 December 2019 The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data, around the Northwest Shelf station (121.5 E, 14 S) for Leg 1 only. The port drop keel position was set to 4 m and the starboard drop keel set to flush with hull for the duration of the voyage. The EK60 was switched off on Leg 1 (00:45 23-Oct-2019) at the request of the Chief Scientist to reduce interference on the ADCP data. This remained off for the duration of Leg 2. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 174 files totalling 8.39 GB of raw data in this dataset (note that raw_ek60 data was only collected on Leg 1) No Post-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 XBT data collected on RV Investigator voyage IN2022_V08, titled "Biodiversity Assessment of Australia’s Indian Ocean Territories", which departed Darwin on September 30 and returned to Fremantle on November 3, 2022. This was a continuation of voyage IN2021_v04. A total of 13 XBT casts were conducted over the duration of this voyage (12 successful and 1 failed drop). 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 the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2019_V06, titled: "Tropical observations of atmospheric convection, biogenic emissions, ocean mixing, and processes generating intraseasonal SST variability." The voyage took place between October 19 and December 17, 2019 departing from Darwin (NT) and arriving in Darwin. Data for 96 deployments (Leg-1) were acquired using the Sea-Bird SBE911 CTD #24, 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. Data for 327 deployments (Leg-2) were acquired using the Sea-Bird SBE911 CTD 24, 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. A Biospherical PAR, Tritech Altimeter, C-Star Transmissometer, WET Labs CDOM, WET Labs ECO Scattering, and WET Labs ECO Chlorophyll 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 multibeam echosounder data collected on RV Investigator voyage IN2019_V06, titled 'Tropical observations of atmospheric convection, biogenic emissions, ocean mixing, and processes generating intra-seasonal SST variability' which departed Darwin on the 19th of October 2019 and returned to Darwin on the 17th of December 2019 ,consisting of two legs. Leg 1 - Darwin, 20:00, 19 October 2019 to Darwin, 19:00, 10 November 2019 Leg 2 - Darwin, 20:00, 11 November 2019 to Darwin, 08:00, 17 December 2019 The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn around the Northwest Shelf station (121.5 E, 14 S) for Leg 1, however was not used in Leg 2 due to shallow water (<100m). 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 467 files totalling 36 GB of raw data in this dataset, covering approximately 1,779 nautical miles. 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.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2019_v06, titled 'Tropical observations of atmospheric convection, biogenic emissions, ocean mixing, and processes generating intra-seasonal SST variability' which departed Darwin on the 19th of October 2019 and returned to Darwin on the 17th of December 2019 ,consisting of two legs. Leg 1 - Darwin, 20:00, 19 October 2019 to Darwin, 19:00, 10 November 2019 Leg 2 - Darwin, 20:00, 11 November 2019 to Darwin, 08:00, 17 December 2019 The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information around the Northwest Shelf station (121.5 E, 14 S) for Leg 1, and between the Warruwi & Berrimah weather stations in Northern Territory for Leg 2. The EM710 provides a 0.5° by 1° transmit and receive angular resolution respectively. The echosounder's nominal frequency range is from 70 to 100 kHz. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. Leg 1 contains 56 files totalling 9.3 GB of raw data, covering approximately 483 nautical miles and Leg 2 contains 279 files totalling 129 GB of raw data, covering approximately 1,448 nautical miles. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format is corrected for motion and position. Tide corrections were not applied to the processed data for Leg 1, but were applied to the processed data for Leg 2. 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 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 Underway (UWY) data collected from the Marine National Facility (MNF) RV Investigator Voyage IN2019_V06, titled: "Tropical observations of atmospheric convection, biogenic emissions, ocean mixing, and processes generating intraseasonal SST variability." The voyage took place between October 19 and December 17, 2019 departing from Darwin (NT) and arriving in Darwin. Standard Underway data is continuously recorded, consisting of: (1) Navigation data (NAV): Latitude, Longitude, Speed, Heading, Course Over Ground, Gyros, and Doppler Log (dual GPS instrument). (2) Thermosalinograph (TSG): Water Salinity, Flow-Rate, Temperature, Fluorescence, pCO2 and Optode/Oxygen. (3) Atmospheric (MET): Humidity, Wind Speed and Direction (vane and ultrasonic), Radiometer/Sea Surface Temperature, Pyranometer/Solar Radiation, Photosynthetically Active Radiation (PAR), Air Temperature, Air Pressure, Rain, Ozone and Trace Gases (port and starboard instruments). The quality-controlled RV Investigator underway meteorological and SST data are supplied to the IMOS AODN where they are publicly available at the "Ships of Opportunity" Thredds server (http://thredds.aodn.org.au/thredds/catalog/IMOS/SOOP/SOOP-ASF/VLMJ_Investigator/catalog.html) for research. From there, they are downloaded by NOAA for their In Situ Quality Monitoring web site (iQUAM2) and made available for satellite SST validation. The SBE 38 SST data are used within the Australian Bureau of Meteorology for real-time satellite SST validation and ingested into real-time SST analyses which are then used as the boundary condition for Numerical Weather Prediction models. The meteorological and SST data are uploaded onto the Global Telecommunications System (GTS) for global dissemination to Meteorological Agencies, and separately supplied to the SAMOS (http://samos.coaps.fsu.edu/html/) Project for air-sea flux research. The real-time SBE 38 SST data are currently (2017) used in the following data products (accessed via the GTS): • International Comprehensive Ocean-Atmosphere Data Set (ICOADS R3.0) (http://icoads.noaa.gov/) • NOAA NCEI Extended Reconstructed Sea Surface Temperature version 4 (ERSST.v4) (https://www.ncdc.noaa.gov/data-access/marineocean-data/extended-reconstructed-sea-surface-temperature-ersst-v4) • Hadley Centre SST Data Set (HadSST3) (http://www.metoffice.gov.uk/hadobs/hadsst3/) • Global Ocean Surface Underway Data (GOSUD) Project (http://www.gosud.org/) • Bureau of Meteorology daily and weekly SST analyses (http://www.bom.gov.au/marine/sst.shtml) • NOAA NCEI “Reynolds” daily global OISST analysis (https://www.ncdc.noaa.gov/oisst) • NASA JPL “MUR” 1 km daily global SST analysis (https://mur.jpl.nasa.gov/) • UK Met Office “OSTIA” daily global SST analysis (http://ghrsst-pp.metoffice.com/pages/latest_analysis/ostia.html) • CMC daily global SST analysis • Ourocean “G1SST” global daily 1 km SST analysis (https://ourocean.jpl.nasa.gov/SST) As part of the underway data gathering system, other datasets are produced (e.g., pCO2, ISAR SST) which are processed separately and have their own metadata records. Data are recorded at 5 second intervals. Near real-time data are available via the link "Visualisation tool for Underway Data." This dataset will be processed and archived within the CSIRO Oceans & Atmosphere (O&A) Information and Data Centre (IDC) in Hobart (TAS). Data are available at time intervals of 5 sec (NetCDF format), 10 sec and 5 min (ASCII format). Additional information regarding this dataset is contained in the Voyage Summary and/or the Data Processing Report for this voyage.

This record describes Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage IN2019_V06, titled: "Tropical observations of atmospheric convection, biogenic emissions, ocean mixing, and processes generating intraseasonal SST variability." The voyage took place between October 19 and December 17, 2019 departing from Darwin (NT) and arriving in Darwin. The voyage was split into two legs, with a 1 day port period in Darwin. The first leg took place from October 19 to November 11, 2019, and the second from November 11 to December 17, 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 the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV Investigator voyage IN2021_T01, titled: "Transit: Brisbane to Darwin". The voyage took place between June 9 to June 23 2021 departing Brisbane and arriving in Darwin. Data for 12 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 final conductivity calibration was based on a single deployment grouping. The final calibration from the primary sensor had a standard deviation (SD) of 0.0033235 PSU, outside 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 0.64275 μM. The agreement between the CTD and bottle data was good. PAR, upward and downward facing Teledyne Lowered Acoustic Doppler Current Profilers (LADCP), Wetlabs C-Star Transmissometer, ECO Chlorophyl and Scattering, CDOM, and UBAT sensors 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 XBT data collected on RV Investigator voyage IN2021_V02 (SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania), which departed Hobart on the 14th April 2021 and returned to Hobart on the 28th April 2021. A total of 9 XBT casts were conducted over the duration of this voyage; 2 of which were discounted, one for testing (xbt_001) and one was a bad cast (xbt_004). 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.