Oceanographic measurements were collected aboard Aurora Australis cruise au1603, voyage 3 2015/2016, from 11th January to ~24th February 2016. The cruise commenced with the K-AXIS project, the major marine science component of the cruise. This was the Australian component (P.I.’s Andrew Constable, Steve Rintoul and others) of a combined biological and oceanographic study in the vicinity of the Kerguelen Axis. After conclusion of marine science work the ship went to Mawson for a resupply. During a storm on 24th February the ship broke free of its mooring lines and ran aground on the rocks at West Arm in Horseshoe Harbour, thus ending the cruise. Expeditioners were eventually taken to Casey on the Shirase, then flown home. Meanwhile the Aurora Australis was refloated and sailed to Fremantle, then on to Singapore for repairs. This report discusses the oceanographic data from CTD operations on the cruise. A total of 47 CTD vertical profile stations were taken on the cruise (Table 1). Over 850 Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients (phosphate, nitrate+nitrite and silicate), dissolved inorganic carbon (i.e. TCO2), alkalinity, POC and PN, and biological parameters, using a 24 bottle rosette sampler. A UVP particle counter/camera system was attached to the CTD package (P.I. Emmanuel Laurenceau). A separate trace metal rosette system was deployed from the trawl deck (P.I. Andrew Bowie). Upper water column current profile data were collected by a ship mounted ADCP, and meteorological and water property data were collected by the array of ship's underway sensors. Eight drifting floats were deployed over the course of the cruise. Processing/calibration and data quality for the main CTD data are described in this report. Underway sea surface temperature and salinity data are compared to near surface CTD data. CTD station positions are shown in Figure 1, while CTD station information is summarised in Table 1. Float deployments (5 x Argo/Apex, 2 x SOCCOM and 1 x Provor) are summarised in Table 10. Further cruise itinerary/summary details can be found in the voyage leader report (Australian Antarctic Division unpublished report: Voyage 3 2015-2016, RSV Aurora Australis, Voyage Leader’s report - see the metadata record "Aurora Australis Voyage 3 2015/16 Track and Underway Data" for access to the Voyage Report).

This is the CTD and Niskin bottle data set from the RV Tangaroa cruise tan0704, 7th Mar 2007 to 29th Mar 2007, along the Macquarie Ridge. This was the deployment cruise for the Macquarie Ridge mooring array. Dissolved oxygen data have been removed from this data set (oxygen bottle data never analysed). There were a total of 75 CTD casts on this cruise.

Profiles of visible light absorption and attenuation coefficients were measured in the upper 100m of the water column. Data Acquisition: The Wetlabs ACS spectral absorption and attenuation meter was mounted on a deployment frame together with a Seabird pump, a Wetlabs DH-4 data logger and two battery packs. This set-up was as recommended in the Wetlabs manual. The logger was set to control the ACS once the on/off magnet had been inserted. The data acquisition program comprised 2 minutes delay time to allow the instrument to be deployed over the stern; 30 seconds warm-up time; 30 seconds flush time during which the pump was activated, and finally 12 minutes of data acquisition. Physically, the instrument was attached to the winch, the magnet was inserted as soon as permission to deploy had been obtained from the bridge, the instrument was lowered directly to 20m, until 1.5 minutes since insertion of the magnet. The instrument was then brought to just below the surface and lowered at 0.5m per second to a depth of 100m, then retrieved at the same speed. Once the instrument was back on deck the magnet was removed to prevent dry operation of the pump. The data logger received an instrument-specific binary format data file for each deployment, with automatic sequential file numbering. These files were uploaded after each deployment. Data Processing: The Wetlabs software program WAP was used to extract ascii data from the binary files. This procedure included corrections for internal instrument temperature and the latest manufacturer's calibration for wavelength. Note that although daily calibrations were performed during the cruise, the manufacturer advised against using these calibrations as conditions were suboptimal (milli-Q water not fresh, environment not totally dry or well temperature-controlled). A matlab script, acs.m, written by the principal investigator, continues the data processing. Data recorded in air are discarded, remaining data are binned to 2m depth intervals, occasional spurious data with a discontinuity in absorption or attenuation spectra are removed, and a correction is applied to account for differences in ocean water temperature and salinity compared to the calibration conditions. This final step uses first-cut CTD data courtesy of the oceanography team (Bindoff et al). Not yet complete (as of 2006-03-10): Remaining spurious data need to be weeded out by hand. These include non-systematic quirks such as occurrence of bubbles or larger particles in the optical path. The depth needs to be corrected for an offset of some 4m plus the difference between the pressure sensor location and the ACS-inlet location. Dataset Format: For each 100m profile, a single ascii file is available, comprising instrument calibration data and a time sequence of attenuation and absorption spectra. By placing each of the profile files from one cruise transect in a single directory, the acs.m routine can be applied to one leg at a time, yielding matlab fields of [station, depth (0:2m:100m), wavelength (87 wavelengths)]. The acs.m script includes details of which CTD station number refers to which ACS file number. This information is also supplied in the station log file jill_brokew_stations.xls. Acronyms Used: ACS - Absorption (a) Attenuation (c) Spectral meter, produced by Wetlabs CTD - Conductivity, Temperature, Pressure. This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679).

This is the CTD data set from RV Tangaroa cruise tan0803, 26th March to 26th April 2008, along the Macquarie Ridge. This was the recovery cruise for the Macquarie Ridge mooring array. The primary aims of the oceanographic program were: 1. recovery of a New Zealand/Australia collaborative mooring array spanning two gaps in the Macquarie Ridge north of Macquarie Island, and 2. occupation of a CTD transect running south from New Zealand to 60o S along the Macquarie Ridge. Eight of the nine moorings were successfully recovered. The mooring at site number 3 (NIWA gear) was unrecoverable, with acoustic release communication indicating only the bottom portion of the mooring remaining and lying flat on the ocean floor. Complete details of the mooring work are included in a separate mooring recovery report. Mooring instruments were downloaded on the ship, with a very high percentage of successful data recording. Ship maneouvering and deck operations all went well throughout the recoveries. Shiptime at the mooring locations was well spent, with daylight hours dedicated to mooring recovery, and night time used for nearby CTD, swath mapping, coring and sea mount activities, and for unspooling of mooring line. The additional container space created on the top deck portside (above the trawldeck) proved extremely valuable for stowage of mooring gear. 58 CTD's were completed during the cruise, including 54 along the main transect, and 4 at coring locations (part of the geology program). Main transect CTD's included 2 across the northern mooring group, and 3 across the southern mooring group. Most casts were to within 25 metres of the bottom. Instrument problems resulted in incomplete casts at the following locations: CTD 9, CTD 11 and CTD 27. CTD 46 was skipped due to bad weather, while further instrument problems prevented a cast at the southernmost site (CTD 50). Niskin bottles were sampled at each station for dissolved oxygen and salinity, with a subset of stations selected for 18O sampling. Some stations were additionally sampled for DIC, alkalinity, 13C, silicate, and U/Th, as part of the geology program. Note that dissolved oxygen data have been removed from this data set, as oxygen bottle samples were never analysed.

Oceanographic measurements were collected aboard RV Investigator cruise in1801 (CSIRO voyage designation in2018_v01) from 11th January to 22nd February 2018, along CLIVAR Southern Ocean repeat meridional section SR3, followed by Adelie land shelf stations, small meridional sections along 150E (the south end of CLIVAR section P11S) and 132E, and several stations along CLIVAR zonal section S4. A total of 108 CTD vertical profile stations were taken on the cruise, most to within 14 metres of the bottom. Over 2800 Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients (phosphate, nitrate+nitrite, silicate, ammonia and nitrite), CFC's plus tracers (CFC-11, CFC-12, SF6 and N2O), dissolved inorganic carbon (i.e. TCO2), alkalinity, pH, C13/C14, genomics, HPLC, POC, chlorophyll, radiogenic isotopes, helium, ice nucleation, and Ca/Mg, using a 36 bottle rosette sampler. Full depth current profiles were collected by an LADCP attached to the CTD package. Upper water column current profile data were collected by a ship mounted ADCP (75 kHz). Trace metal rosette and in situ pump deployments were done at some of the CTD stations. Meteorological and water property data were collected by the array of ship's underway sensors. A large assortment of 29 drifting floats was deployed throughout the cruise. A detailed data report is included with the data set, with summary of all CTD data and important data quality information. The data set contains CTD 2dbar averaged data, and Niskin bottle data (core hydrochemistry of salinity, dissolved oxygen and nutrients, plus CFC-11, CFC-12, SF6 and N2O), in text and matlab formats. A WOCE (CCHDO) 'exchange' format version of the data is also available from the CCHDO data centre.

Oceanographic measurements were collected aboard Aurora Australis cruise au1602, voyage 2 2016/2017, from 8th December 2016 to 21st January 2017. The cruise commenced with a Casey resupply, followed by work around the Dalton Polynya/Moscow University Iceshelf, then the Mertz Glacier region, and then around the Ninnis Polynya. 14 stations at the southern end of the SR3 transect were also completed. Ice conditions prevented access to the front of the Totten Glacier. A total of 73 CTD vertical profile stations were taken on the cruise, most to within 12 metres of the bottom (Table 1). Over 800 Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients (phosphate, nitrate+nitrite, silicate, ammonia and nitrite), dissolved inorganic carbon (i.e. TCO2), alkalinity, Th-234, POC, Chla, PAM, HPLC, Nd, Po-210/Pb-210, bacteria, O-18, caesium, and Teflon pollutants, using a 24 bottle rosette sampler. Full depth current profiles were collected by an LADCP attached to the CTD package. Upper water column current profile data were collected by a ship mounted ADCP. Meteorological and water property data were collected by the array of ship's underway sensors. 8 Argo floats were also deployed (Table 13) on the transit from Hobart to Casey. The data set contains CTD dbar data and Niskin bottle data (i.e. core hydrochemistry only - salinity, dissolved oxygen and nutrients). A detailed data report is included, with a description of the data and important data quality information.