These are phytoplankton pigment datasets collected on the BROKE voyage of the Aurora Australis during the 1995-1996 summer season. The readme file in the data download states: Data supplied by Dr Simon Wright. Details phytoplankton pigment data from BROKE. "BROKEPIGDBase.xls Contains 5 worksheets. 'Notes' repeats the information presented here. 'Key' describes the column headings, chemical names. 'Raw_Data' is the exact spreadsheet receieved from Dr Wright. 'Standard_sample_source' contains all the phyto-chemical data as taken from the CTD programme. 'Non_standard_sample_source' contains phyto-chemical data that seems to have been collected opportunistically, to test some assumptions. The details of the locations of the opportunistic samples are detailed in the column 'Sample_source'. Note- it is unsure whether the numbers in the CTD column describe the Station Number. This has to be verified. Converted into a MS Access database- 'BROKE_phytoplankton.mdb' by Natalie Kelly. This database contains 3 tables. One is a description of the column names, chemical etc. The other two contain both the Standard and Non-Standard Sample source phytochemical data. Natalie Kelly 19 November 2005"

Chloropyll a data were collected along the WOCE transect on voyage 1 of the Aurora Australis, during October of 1991. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

These data relate to a large-scale early-autumn phytoplankton bloom that occurred off Cape Darnley, East Antarctica, in March 2012. The bloom was detected by Dr Jan Lieser (Antarctic Climate and Ecosystems Cooperative Research Centre, ACE-CRC) through MODIS satellite and was opportunistically sampled from RSV Aurora Australis using the uncontaminated seawater line. Samples were analysed for protist species and abundances using light and scanning electron microscopy, and pigment analyses were conducted using high performance liquid chromatography. Additional water samples were taken for dissolved nutrient analyses. Specific details of the files are: Cape Darnley Protist Counts Samples were preserved with 1 % vol:vol Lugols iodine and stored in glass bottles in the dark at 4 degrees C. Protists were identified and counted using phase and Nomarski interference optics using Olympus IX71 and IX81 inverted microscopes at 400X to 640X magnification. Bright field optics were also used to discriminate taxa that contained chloroplasts. Protistan taxa were counted in 20 randomly chosen fields of view, except for highly abundant taxa that were counted in a subset of the field of view defined by an ocular quadrant (Whipple grid). Cell biovolumes and carbon conversion statistics were used to calculate the cell biomass of protistan taxa/groups. Cape Darnley Fluorometer Calibration Fluorometer measurements from the ships underway system were calibrated using chlorophyll a readings determined through high performance liquid chromatography. A linear relationship was established between fluorometer v HPLC chlorophyll a measurements at the same sites. The linear equation was then used to convert all underway fluorometry data from the voyage. Cape Darnley Bloom HPLC Pigments CHEMTAX summary Major phytoplankton groups at each site determined through analysis of pigments using high performance liquid chromatography and CHEMTAX. Methods were according to that of Wright et al. (2010). Cape Darnley Bloom Nutrients Dissolved nutrient concentrations. Samples were analysed by the Department of Primary Industries, Parks, Water and Environment, 18 St. Johns Avenue, Newtown, Tasmania 7008. Cape Darnley Underway Data VOYAGE_04_0_201112 Raw underway data from Aurora Australis in the bloom region Cape Darnley Underway Data Maps Maps of the underway data in the bloom region

Processed CTD instrument data - Corrected fluorescence profiles at the Southern Kerguelen Plateau, Indian Sector of the Southern Ocean. The fluorometer was calibrated through the regression of burst measurements against in situ chlorophyll a measured at the same depths and sites using high performance liquid chromatography (Wright et al. 2010). Zero chlorophyll a reference points were included in the regression and were obtained through averaging fluorometry data over 200-300 m bins. The resulting linear equation used to convert flourometry data was: chlorophyll = 0.262*fluorescence + 0.101. Column measurements (µg L-1) and integrated data (0-150 m, mg m-2) for each CTD station are provided.

This dataset contains chlorophyll a data collected by the Aurora Australis on Voyage 7, 1992-1993 - the WOES (Wildlife Oceanography Ecosystem Survey) cruise. Samples were collected from March-May of 1993. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

This dataset contains chlorophyll a data collected by the Aurora Australis on Voyage 6, 1997-1998 - the SAZ (Subantarctic Zone) cruise. Samples were collected in March of 1998. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

At each CTD station the Fast Repetition Rate Fluorometer (FRRF) was carried out onto the trawl deck and shackled (+ cable tie) to the winch cable. When the crew in the aft control room were ready the PAR (Photosynthetically Active Radiation) cap was removed and the FRRF activated with the magnet. It was deployed at a rate of 0.3m/sec to 10m, stopped for 30sec, then the descent was continued to 100m at same rate where it was stopped for another 30 sec. The FRRF was then brought back up at 0.3m/sec to deck. Once on deck the FRRF was turned off, it was hosed down with hot fresh water and the PAR cap replaced. Underway data were collected from the flow-through system in the lab on all South/North transects. West to East legs were not surveyed. The FRRF data were downloaded after every Vertical Drop and at the end of the Underway legs. The post-processing and analysis of data will be carried out after the voyage. The Final dataset is in the form of a Binary file for each drop and Underway leg. This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679).

This dataset contains chlorophyll a data collected by the Aurora Australis on Voyage 2, 1997-1998 - the ONICE cruise. Samples were collected from September-November of 1997. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

Metadata record for data from ASAC Project 2702 See the link below for public details on this project. Sea-ice algae are the basis of the Antarctic food web and are essential for healthy functioning of the Antarctic ecosystem. These algae exploit a unique niche within this extreme environment. Using advanced photosynthetic analysis we will examine the mechanisms which influence the productivity of sea-ice algae. The objective of this project is to understand the processes of light acclimation and photo-protection employed by sea-ice algae under extremely low temperature conditions. Several new hypotheses have been proposed in a recent review of low temperature acclimation of higher plants (Oquist and Huner, 2003). To further understand the remarkable tolerance of sea-ice algae to photoinhibition, we propose to test several of these hypotheses. Sea-ice algae fix inorganic carbon that forms the basis of the Southern Ocean food web. Sea ice covers up to 20 million km2 of the Southern Ocean each year. Global climate change will decrease the sea-ice thickness and distribution (IPCC, 2001); however subtle changes in temperature and light penetration will also have profound negative impacts on the photosynthetic efficiency of the sea-ice microalgae before any macroscale changes take place. Sea-ice algae are essentially the only food source for invertebrates and fish for up to nine months of the year. During winter and spring, krill (Euphausia sp.) have been observed feeding directly on sea-ice algae. Further, changes in sea-ice productivity will have a cascade effect further up the food web. Therefore, understanding how physical driving forces (temperature and light) affect sea-ice algae productivity will be critical to our ability to predict the effects of climate change and sustainably manage this unique and vulnerable ecosystem. Our primary objective is: To understand the processes of light acclimation and photo-protection employed by sea-ice algae under extremely low temperature conditions, with an aim to better understanding the potential implications of global climate change on the Antarctic sea-ice ecosystem.

The dataset lists key biogeochemical parameters measured in sea ice during the SIPEX2 voyage, including dissolved and particulate iron and other trace metals, macronutrients (silicic acid, nitrates+nitrite, phosphoric acid and ammonium), iron binding organic ligands, dissolved and particulate organic carbon, Cholophylla, thermodynamics (temperature, salinity, brine volume and Rayleigh number). All sampling bottles and equipment were decontaminated using trace metal clean techniques. Care was taken at each site to select level ice with homogeneous snow thickness. At all the stations, the same sampling procedure has been used : Firstly, snow was collected using acid cleaned low density polyethylene (LDPE) shovels and transferred into acid-cleaned 3.8 l LDPE containers (Nalgene). Snow collected was analysed for temperature, salinity, nutrients, unfiltered and filtered metals. Snow thickness was recorded with a ruler. Ice cores were collected using a non-contaminating, electropolished, stainless steel sea ice corer (140 mm internal diameter, Lichtert Industry, Belgium) driven by an electric power drill. Ice cores were collected about 10 cm away from each other to minimise between-core heterogeneity. A first core was dedicated to the temperature, salinity and Chlorophyll a (Chla). To record temperature, a temperature probe (Testo, plus or minus 0.1 degrees C accuracy) was inserted in holes freshly drilled along the core every 5 to 10 cm, depending on its length. Bulk salinity was measured for melted ice sections and for brines using a YSI incorporated Model 30 conductivity meter. Chla is processed on board using a 10 AU fluorometer (turner Designs, sunnyvale California). The total length of this core is cut in sections of 7 cm. The second core is dedicated to the POC/PON (Particulate Organic Carbon/ Particulate Organic Nitrogen), DOC (Dissolved Organic Carbon) and nutrients. Six sections of 7 cm were sub-sampled from this core. The six sections were chosen so that two top, two intermediate and two basal sections. Two cores are taken for the trace metal analysis. Those cores were directly triple bagged in plastic bags (the inner one is milli-Q washed) and frozen at -20degrees C until analysis at the laboratory. Brine samples were collected by drainage from “sack holes”. Brines and under ice seawater (~1 m deep) were collected in 1 l Nalgene LDPE bottles using an insulated peristaltic pump and acid cleaned C-flex tubing (Cole Palmer). All samples were then transported to the ship as quickly as possible to prevent further freezing. Samples were used to analyse unfiltered and filtered metals, Chla, POC/PON, nutrients and DOC. Filtration for filtered metals was completed on board using a peristaltic pump and a 0.2 microns cartridge filter. All the unfiltered and filtered metals collected were acidified (2 ppt HCl seastar) and stored at room temperature until analysis at the laboratory. Nutrients, DOC and filters for POC/PON were stored frozen at -20 degrees C until analysis at Analytical Service Tasmania, Hbart. Chla filtrations and analysis were completed on board. The file "SIPEX2 sea ice data" lists key biogeochemical parameters in sea ice cores, snow, brine and underice seawater (1m depth) collected during the SIPEX2 voyage (64.26-65.15S/116.44-120.58E) carried out between the 26th of september and 29th of october 2012. The acid-cleaning protocols for sample bottles and equipment followed the guidelines of GEOTRACES (www.geotraces.org). Contamination-free ice coring equipment developed by Lannuzel et al. (2006) was used to collect ice cores. Ice cores were triple bagged and stored at -18 degrees C until further processing in the home laboratory. Ice cores were then sectioned under a class-100 laminar flow hood (AirClean 600 PCR workstation, AirClean System) using a medical grade stainless steel bonesaw (Richards Medical), thouroughly rinsed with ultra-high purity water (18.2 MO), and ice sections were then allowed to melt at ambient temperature in acid-cleaned 3 L Polyethylene (PE) containers. Melted sea-ice sections were then homogenized by a gentle shake and filtered through 0.2 microns pore size polycarbonate filters (Sterlitech, 47 mm diameter) using Teflon(R) perfluoroalkoxy (PFA) filtration devices (Savillex, USA) connected to a vacuum pump set on less than 2 bar to obtain the particulate (greater than 0.2 microns) and dissolved (less than 0.2 microns) metal fractions. The collected filtrates (less than 0.2 microns) were acidified to pH 1.8 using Seastar Baseline(R) HCl (Choice Analytical) and stored at ambient temperature until analysis in the home laboratory. The filters retaining the particulate material were stored frozen in acid-clean petri dishes until further processing. Standard physico-chemical and biological parameters such as sea-ice and snow thicknesses, in situ ice temperature, sea-ice and brine salinities, ice texture, chlorophyll a (Chla), macro-nutrients (nitrate+nitrite (NOx), phosphate (PO43-), silicic acid (Si(OH)4-) and ammonium (NH4+)), dissolved organic carbon (DOC), and particulate organic carbon and nitrogen (POC and PON) were also determined in each sample at Analytical Service Tasmania (Hobart, Australia) within 6 months of sample collection. Dissolved inorganic nutrients were determined using standard colorimetric methodology (Grasshoff et al., 1983) as adapted for flow injection analysis using an auto-analyzer. Theoretical brine volume fractions (Vb/V) were calculated using in situ ice temperatures and bulk ice salinities and relationships from Cox and Weeks (1983). The full ice core length was examined under crossed-polarised light to identify the texture (i.e., columnar vs granular) according to the method of Langway (1958). Preparation of the thin sections took place in a container kept at -25 degrees C. The thin sections were obtained by cutting vertical sections of about 6 mm thick using a band saw. Ice sections were then thinned down using a microtome blade to reach a final thickness of 3 - 4 mm and observed under cross-polarized lights The acidified filtrates were diluted 5 times, using 2 % v:v ultrapure HNO3 (Seastar Baseline, Choice Analytical) and dissolved metals concentrations were determined directly using sector field inductively coupled plasma magnetic sector mass spectrometry (SF-ICP-MS; Element 2) following the method described in Lannuzel et al. (2014). Filters retaining particulate material (greater than 0.2 microns) were digested in a mixture of strong, ultrapure acids (750 micro litres 12N HCl, 250 microlitres 40% HF, 250 microlitres 14N HNO3) in 15 mL Teflon(R) perfluoroalkoxy (PFA) (Savillex, USA) on a Teflon coated graphite digestion hot plate housed in a bench-top fume hood (all DigiPREP from SCP Science, France) coupled with HEPA(R) filters to ensure clean air input at 95 degrees C for 12 h, then dry evaporated for 4 h and re-suspended in 2 % v:v HNO3 (Seastar Baseline, Choice Analytical). The procedure was applied to filter blanks and certified reference materials BCR-414 and MESS-3 to verify the recovery of the acid digestion treatment. The concentrations of particulate metals were then determined by SF-ICP-MS (Bowie et al., 2010). Results for procedural blanks, limits of detection and certified reference materials were found fit for purpose. The file "SIPEX2 TMR data" lists macro-nutrients concentrations, as well as dissolved iron concentrations collected using a Trace Metal Rosette (TMR) deployed over 1000m depth in the sea ice zone. Dissolved iron (DFe) and iron in the 2+ redox state (FeII) in nanomoles per Litre (nmol/L) were measured onboard using FIA-CL technique explained in Schallenberg et al (2015). Standard deviation associated with the analysis of the samples is indicated by "SD". Dissolved Fe(III): Dissolved Fe in this study is operationally defined as the Fe fraction that passes through a 0.2 microns filter. A modified flow injection analysis (FIA) method was used to measure dFe that relies on the detection of Fe(III) with the chemiluminescent reagent luminol (de Jong et al., 1998; Obata et al., 1993). Samples and standards were treated with hydrogen peroxide (H2O2; final concentration = 10 micro mols) at least 1 hour prior to measurement to oxidize any Fe(II) that might be present (Lohan et al., 2005). The system buffers the samples in-line to pH = 4 before passing them for 3 minutes through a pre-concentration column packed with 8-hydroxyquinoline chelating resin (8-HQ). A solution of 0.3 M HCl (Seastar) then elutes Fe(III) from the resin and mixes with 0.8 M ammonium hydroxide (NH4OH), 0.1 M H2O2 and 0.3 mM luminol containing 0.3 mM triethylenetetramine (TETA) and 0.02 M sodium carbonate (Na2CO3), yielding an optimum luminol chemiluminescence reaction pH of 9.5. The resulting solution is passed through a ~5 m mixing coil maintained at 35 degrees C before being pumped to the flow cell mounted in front of a photo-detector. System blanks were 0.014 plus or minus 0.004 nM, yielding a detection limit (3 x blank standard deviation) of 0.013 nM. Results for SAFe reference materials for Fe were in good agreement with consensus values (see Table 1). Dissolved Fe(II): Fe(II) was determined by luminol chemiluminescence detection following the approach of Hansard and Landing (2009) but without sample acidification. Sampling began within minutes after the first Niskin bottle (always from the surface) arrived in the clean container. Samples were analyzed within 2 minutes of filtration and were pumped simultaneously with the luminol reagent into a spiral flow cell made of flexible Tygon(TM) tubing (ID = 0.7 mm) that was mounted in front of a photomultiplier tube (Hamamatsu H9319-01) in a custom-made light-tight box. Flow rates for luminol and sample were ~4.5 mL/min. The photomultiplier tube was operated at 900 V with a 200 ms integration time. Photon counts were recorded using FloZF software (GlobalFIA) and were averaged over 10 second intervals with 5 replications for each sample and standard. The relative standard deviation of these repeat measurements was between 1 and 3%. The luminol recipe for 1 L reagent is as follows: 0.13 g luminol, 0.34 g Na2CO3, 40 mL concentrated NH4OH and 10-12 mL concentrated HCl (Seastar). This results in 0.75 mM luminol with 3.2 mM Na2CO3. The pH of the reagent is adjusted to ~10.0 with small amounts of NH4OH and HCl. It was found that luminol sensitivity increases with age, so batches were prepared well in advance and used up to 3 months later. Fe(II) calibration curves were obtained with Fe(II) standard additions in the range 0-100 pM. A 10 mM standard of ammonium iron(II) sulfate hexahydrate was prepared fresh in 0.1 M Seastar HCl and considered stable in the fridge for up to a month. From this stock solution, intermediate standards (50 micro mols and 50 nM) were prepared in 0.05 M Seastar HCl no more than 10 minutes prior to measurement. Standards were added to seawater that had been collected at earlier stations in the cruise and been left in the dark for greater than 24 hours. Previous investigators (e.g., Rose and Waite, 2001) have commented on the light-sensitivity of the luminol reagent, and it is therefore frequently stored in the dark.