RV Investigator Voyage IN2017_V02 CTD Data

This record describes the Conductivity-Temperature-Depth (CTD) data collected from the Marine National Facility RV 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 16 to 27 March 2017 departing from Hobart (TAS) and returning to Hobart (TAS). Data for 11 deployments were acquired using the Seabird SBE911 CTD unit 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.Processing was completed using CapPro processing software, version 2.4.For the duration of the voyage significant spikes were observed across all recorded sensor channels. Investigation strongly suggests electrical interference was the cause of the data spikes, as mitigation measures have alleviated the issue. Care was taken in post processing to remove the spikes while maintaining true data features. The nature of the spiking was primarily extreme values persisting for a single scan, which were suitably detected and flagged by evaluating the second-difference of the data.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. 001173 PSU, well 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 final Oxygen calibration from the secondary sensor had a S.D of 0.5443 uM. The agreement between the sensor and bottle data was very good. Both Oxygen sensors calibrated closely.The Biospherical photosynthetically active radiation (PAR), Wetlabs Transmissometer, the Wetlabs ECO chlorophyll, and O&A IMU 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.