Aurora Australis Southern Ocean oceanographic (CTD) data, cruise au9206 (FISHOG)

Oceanographic measurements were conducted in the Southern Ocean around Heard and McDonald Islands, and in the Prydz Bay region, from January 1992 to March 1992. A total of 168 CTD (conductivity, temperature and depth) vertical profile stations were taken, most to near bottom. Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients (phosphate, nitrate+nitrite, silicate), chlorofluorocarbons, helium, tritium, dissolved inorganic carbon, alkalinity, carbon isotopes, dissolved organic carbon, dimethyl sulphide/dimethyl sulphoniopropionate, iodate/iodide, oxygen 18, primary productivity, and biological parameters, using a 24 bottle rosette sampler. CTD salinity data have been calibrated against bottle samples, although the calibration quality varies over the cruise. CTD salinity accuracies can be summarised as follows: Stations 1-26: no bottle samples; conductivity calibration from later stations applied; accuracy therefore unknown. Stations 27-102: accuracy approximately 0.005 (PSS78). Stations 83-93: residuals a bit lower than surrounding stations: data uncertainty may be slightly increased. Stations 103-111: no bottle samples; conductivity calibration from surrounding stations applied; accuracy therefore unknown. Stations 112-168: significant increase in data scatter; accuracy approximately 0.010 (PSS78). The bottle data file contains salinities and nutrients. Dissolved oxygen data exist only as titration values recorded on the laboratory analysis sheets. The nutrient data show a fair amount of scatter, particularly when looking at the nitrate vs phosphate ratios. These data should be used with caution. Measurement and data processing techniques are described, and a summary of the data are presented in graphical and tabular form. The fields in this dataset are: oceanography ship station number date start time bottom time finish time cruise start position bottom position finish position maximum position bottom depth pressure temperature (T-90) salinity sigma-T specific volume anomaly geopotential anomaly dissolved oxygen fluorescence photosynthetically active radiation niskin bottle number