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.
