Southern Ocean CTD data collected from the CASO cruise of the Aurora Australis, 2007-2008

• Other Authors: AADC (originator), AU/AADC > Australian Antarctic Data Centre, Australia (resourceProvider)
• Format: Dataset
• Language: unknown
• Published: Australian Ocean Data Network
• Subjects: oceans; DISSOLVED GASES; EARTH SCIENCE; OCEAN CHEMISTRY; NITRATE; NUTRIENTS; OXYGEN; PHOSPHATE; OCEAN CURRENTS; OCEAN CIRCULATION; FLUORESCENCE; OCEAN OPTICS; PHOTOSYNTHETICALLY ACTIVE RADIATION; WATER TEMPERATURE; OCEAN TEMPERATURE; CONDUCTIVITY; SALINITY/DENSITY; SALINITY; SALINOMETERS; OXYGEN ANALYZERS; CTD > Temperature; Depth; ADCP > Acoustic Doppler Current Profiler; SHIPS; R/V AA > R/V Aurora Australis; AMD/AU; CEOS; AMD; ACE/CRC; OCEAN > SOUTHERN OCEAN; GEOGRAPHIC REGION > POLAR; Antarctic; Southern Ocean; Austral; Adelie Depression; Adelie Land; Antarc*; Antarctica; aurora australis; Australian Antarctic Division; International Polar Year
• Online Access: https://researchdata.ands.org.au/southern-ocean-ctd-2007-2008/687280; https://data.aad.gov.au/metadata/records/au0806_CASO_CTD; http://data.aad.gov.au/aadc/portal/download_file.cfm?file_id=3005; https://secure3.aad.gov.au/proms/public/projects/report_project_public.cfm?project_no=2652; https://secure3.aad.gov.au/proms/public/projects/report_project_public.cfm?project_no=2792; http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=au0806_CASO_CTD

Further information about the quality of these data are available in the readme file and the pdf report contained in the download. Taken from the readme file: * The following CTD 2 dbar data are suspect (not removed from the data files) (this same information is in the file sussctd.dat): stn parameter pressure (dbar) comment --- --- --- --- 4 oxygen 4-18 transient error at the start 5 oxygen 4-102 transient error at the start 15 oxygen 3768 fouling after bottom contact 47 oxygen 200-2000 maybe inaccurate by up to ~2umol/l due to lack of bottle samples 64 oxygen 250-1700 reduced accuracy due to small number of bottle samples * The following bottle oxygen values are suspect (out by ~3-5 umol/l, not removed from the data files) (this same information is in the file sussox.dat): stn bottle --- --- 16 16 19 9 36 1 38 11 66 1 * Suspect nutrient values are listed in the file sussnut.dat * Bad salinity bottle samples are listed in the file badsalbtl.dat * For station 15, all upcast CTD burst temperature, conductivity and salinity data have been removed from the bottle data file - data are bad, due to fouling from bottom contact at the bottom of the cast. * The complete data report is in the file a0803_a0806.pdf Taken from the accompanying report: Oceanographic measurements were collected aboard the Aurora Australis on cruise au0806 (voyage 6 2007/2008, 22nd March 2008 to 17th April 2008). This cruise completed the CASO oceanographic program begun on the CEAMARC cruise (au0803, voyage 3 2007/2008), with a full occupation of the SR3 transect between Antarctica and Tasmania. CASO program objectives were: 1. to measure changes in water mass properties and inventories throughout the full ocean depth between Australia and Antarctica along 140oE (the CLIVAR/WOCE repeat section SR3), as part of a multi-national International Polar Year program to obtain a circumpolar snapshot of the Southern Ocean in austral summer 2007-8; 2. to estimate the transport of mass, heat and other properties south of Australia, and to compare results to previous occupations of the SR3 line and other sections in the Australian sector; 3. to deploy moorings near the Adelie Depression (142-145oE) as part of a joint Australia-France-Italy program to monitor changes in the properties and flow of Adelie Land Bottom Water; 4. to identify mechanisms responsible for variability in ocean climate south of Australia. The CASO program (with a full occupation of the SR3 transect) was originally scheduled for a single cruise. The shipping schedule was re-arranged following an unexpected period in drydock, due to a problem with the ship's thrusters, and as a result the CASO program was split over the two cruises. Several of the southern stations occupied on the first cruise au0803 were repeated on the second cruise au0806, to minimise the impact on the data set of the time gap between the cruises. A total of 131 CTD vertical profile stations were taken on au0803, and 73 CTD station were taken on au0806, most to within 20 metres of the bottom. During the 2 cruises, over 2900 Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients (phosphate, nitrate+nitrite and silicate), 18O, CFC's, dissolved inorganic carbon, alkalinity, 14C, dissolved organic carbon, density (i.e. analysis of the effect of water composition on water density), germanium/silica/boron isotopes, trace metals, neodymium, chlorophyll-a, cell counts, pigments, genetic analyses, and other biological parameters, using a 24 bottle rosette sampler. Full depth current profiles were collected by an LADCP attached to the CTD package, while upper water column current profile data were collected by a ship mounted ADCP. Data were also collected by the array of ship's underway sensors. This report describes the processing/calibration of the CTD data, and details the data quality. An offset correction is derived for the underway sea surface temperature and salinity data, by comparison with near surface CTD data. CTD station positions are shown in Figures 1 and 2, while CTD station information is summarised in Table 1. Mooring and drifter deployments/recoveries are summarised in Table 14. Mooring data from the Adelie Depression deployments are discussed in the mooring data reports Rosenberg (unpublished report, 2009) and Meijers (unpublished report, 2009). Further cruise itinerary/summary details can be found in the voyage leader reports (Australian Antarctic Division unpublished reports: Riddle, V3 2007/08 VL report; Rintoul, V6 2007/08 VL report). Hydrochemistry and CFC cruise reports are in Appendix 1 and Appendix 2. Details about the data are available in a readme file and a full report in the download file.