Southern Ocean CTD and Bottle Data from 1993 Cruise

Oceanographic measurements from 58 CTD vertical profile stations were collected north of Heard Island between August and October 1993. The dataset includes conductivity, temperature, depth profiles and associated water sample data for salinity, dissolved oxygen, and multiple nutrients. Data were collected by the Australian Antarctic Data Centre (AU_AADC) during the au9301/THIRST cruise.

Use Cases

• Analyze vertical profiles of temperature, salinity, and pressure to model water mass structure and stratification.
• Correlate dissolved oxygen and fluorescence measurements with photosynthetically active radiation to study primary productivity.
• Investigate nutrient distributions by examining silicate, phosphate, and nitrate+nitrite data from bottle samples.
• Map the geospatial extent of the cruise using start, bottom, and finish position columns to visualize the survey track.
• Calibrate CTD-derived salinity values against bottle sample salinities to assess instrument accuracy.

Strengths

• 58 CTD vertical profile stations provide detailed water column snapshots.
• Multiple calibrated parameters, with salinity accuracy reported as approximately 0.005 (PSS78).
• Dataset includes a wide range of biogeochemical measurements from bottle samples, including nutrients, dissolved inorganic carbon, and isotopes.

Limitations

• Temporally limited to a single cruise from 1993, offering only a historical snapshot.
• Spatial coverage is restricted to the region north of Heard Island in the Southern Ocean.
• Some nutrient data exist only in legacy laboratory program files ('DAPA') on floppy disks, complicating access.

Provenance

Source

Australian Antarctic Data Centre (AU_AADC).

Collection Method

Measurements from ship-based CTD casts and Niskin bottle water samples collected via a 24-bottle rosette sampler.

Time Range

August 1993 to October 1993.

Freshness

Data collection concluded in October 1993; no updates are expected.

Geography

Southern Ocean, north of Heard Island.