Aurora Australis Marine Science Cruise AU1602, Dalton, Mertz and Ninnis CTDs - Oceanographic Field Measurements and Analysis

Published: 2018-09-09

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. WOCE exchange format for water samples analysed on au1602. 1. Date (yyyyMMdd), time(HHmm), location (decimal degrees), station depth (M), water sample pressure (dbar) 2. CTD salinity data (PSS78) for calibration against salinity bottle data, collected as the average of 10 seconds of upcast burst data centred on each Niskin bottle firing. 3. CTD temperature data (degC T90) collected as the average of 10 seconds of upcast burst data centred on each Niskin bottle firing. 4. Hydrochemistry measurements on water samples collected using Niskin samplers mounted on a 24 bottle rosette for dissolved macronutrients (nitrate+nitrite, silicate and phosphate), dissolved oxygen, dissolved inorganic carbon and titration alkalinity all in units of micromol/kg. 5. Salinity measurements on water samples made using a Guildline Autosal 6. Transmittance, Photosynthetically Active Radiation and Fluorescence data collected from CTD sensors as the average of 10 seconds of upcast data centred on each Niskin bottle firing.