| Summary: | Progress Code: completed Statement: The corrected fluorometer dataset is a 2 minute average dataset, and has been corrected to match the HPLC surface data and the interpolation includes a correction for irradiance. Taken from the draft paper: Materials and Methods Oceanography Oceanographic profiles were collected at 120 CTD stations from RV Aurora Australis using a Seabird SBE9 plus CTD and 24 bottle rosette frame equipped with 10 L Niskin bottles, as described by Rosenberg (2006). Interpretation of oceanographic features follows Williams et al. (this issue). In this paper, the mixed layer depth is defined as the depth at which SigmaT exceeds that at 8 m by 0.02, and the pycnocline is the depth of maximum Brunt-Vaisala frequency Sample collection Samples were normally collected at twelve depths - 10, 20, 30, 40, 50, 60, 70, 80, 100, 120, 150, 200 metres - although this was reduced to eight depths on deeper casts when fewer bottles were available in the upper water column. Seawater (1-2 L) from Niskin bottles or the ship's clean seawater line was filtered onto 13mm Whatman GF/F filters (0.7 micron nominal pore size) using vacuum less than 0.5 atm, while protected from light. The filters were blotted dry and frozen in 1.2 ml internal thread cryotubes in liquid nitrogen for return to Australia. HPLC analysis The pigments were extracted by a modification of the method of Mock and Hoch (2005). Filters were extracted in the cryotube as follows: 300 micro litre dimethylformamide plus 50 micro litre methanol (containing 140 ng apo-8'-carotenal (Fluka) internal standard) were added, shaken briefly, then filters were soaked for 1 hr in the freezer (-18 degrees C) with approximately 0.6g zirconia beads (0.7mm dia., Biospec) added. Tubes were shaken for 20 sec at 4800 cycles/min (Biospec Products Mini-BeadBeater). This reduced the filter to a milky suspension. The extract was cleared of particulate matter by centrifugation, as follows: the base of the cryotube was pierced with a hot needle, the cryotube was placed on top ...
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