Coccolithophore fluxes were investigated over a one-year period (2001-02) at the southern Antarctic Zone in the Australian Sector of the Southern Ocean at the site of the Southern Ocean Iron Release Experiment (SOIREE) near 61°S, 140°E. Two vertically moored sediment traps were deployed at 2000 and 3700 m below sea-level during a period of 10 months. In these data sets we present the results on the temporal and vertical variability of total coccolith flux, species composition and seasonal changes in coccolith weights of E. huxleyi populations estimated using circularly polarised micrographs analysed with C-Calcita software. A description of the field experiment, diatom and biogeochemical fluxes can be found in Rigual-Hernández et al. (2015), while a detailed description of sample processing and counting of coccolithophores can be found in Rigual-Hernández et al. (2018). Moreover, an explanation of the estimation of Emiliania huxleyi coccoliths using C-Calcita software can be also found in Rigual-Hernandez et al. (2018). Coccolithophore assemblages captured by the traps were nearly monospecific for Emiliania huxleyi morphotype B/C. Coccolith fluxes showed strong seasonal cycle at both sediment trap depths. The maximum coccolith export occurred during summer and was divided into two peaks in early January (2.2 x 109 coccoliths m-2 d-1 at 2000 m) and in mid-February (9.8 x 108 coccoliths m-2 d-1). Coccolith flux was very low in winter (down to ~7 x 107 coccoliths m-2 d-1). Coccolith fluxes in the deeper trap (3700 m) followed a similar pattern to that in the 2000 m trap with a delay of about one sampling interval. Coccoliths intercepted by the traps exhibited a weight and length reduction during summer. The annual coccolith weight at both sediment traps was 2.11 plus or minus 0.96 and 2.13 plus or minus 0.91 pg at 2000 m and 3700 m, respectively. Our coccolith mass estimation was consistent with previous reports for morphotype B/C in other regions of the Southern Ocean. Data available: two excel files containing sampling dates and depths, raw counts, relative abundance and fluxes (coccoliths m-2 d-1) of the coccolithophore species, and morphometric measurements of Emiliania huxleyi coccoliths made with C-Calcita software. Each file contains four spreadsheets: raw coccolith counts, relative abundance of coccolithophore species and coccolith flux of each coccolithophore species identified and E. huxleyi morphometrics. Detailed information of the column headings is provided below. Cup – Cup (=sample) number Depth – vertical location of the sediment trap in meters below the surface Mid-point date - Mid date of the sampling interval Length (days) – number of days the cup was open

Preliminary Metadata record for data expected from ASAC Project 1343 See the link below for public details on this project. Comparative study of the processes controlling carbon export in Southern Ocean environments characterised by a different hydrodynamical and ecological functioning. Work on this project was carried out on Voyage 3 of the Aurora Australis (CLIVAR) of the 2001 and 2002 season. Work at sea target sampling sites were the 8 'particle stations' along the CLIVAR SR3 repeat transect: the SAZ at 47 degrees and 49 degrees S; the SAF at 51 degrees S; the PFZ at 54 degrees S; the IPFZ at 57 degrees S; the SPZ at 59 degrees and 61 degrees S; the SACCF at 63 degrees S and the SSIZ at 64 degrees S. Some of these (64 degrees, 61 degrees and 51 degrees S) were sampled again on the way back to assess temporal evolution. All proxy studies (new production; Ba; delta30Si; 234Th-deficit) were done at each particle station but not necessarily on the same CTD casts. New production assessment Surface water (at 5, 25, 50 and 70m) was sampled with the CTD rosette at all particle stations. Different aliquots of 1L seawater were spiked with 15N-nitrate, 15N-ammonium or 15N-urea. All samples were spiked with 13C-bicarbonate; the latter in order to assess net primary production rates. Incubations (12 H) were done in a thermo stated algal cabinet, using appropriate neutral density screens for samples from depths below 5m. The samples were submitted to a constant light flux of 0.7x10power16 quanta/cm2/sec. Furthermore, samples from 5m depth were amended with increasing doses of ammonium (+0.1 micro M; +0.25 micro M; +0.5 micro M and +1 micro M) having natural 15N/14N abundance to assess susceptibility of N-uptake (ammonium, nitrate, urea) to ammonium. Similar experiments were run for three iron amended and control cultures in collaboration with Pete Sedwick, Dave Hutchins and Phil Boyd. Analysis of ammonium related to the incubation work was done on board by colorimetry. As a side product we obtained ammonium profiles at all particle stations and also six shallow CTD's in the southern part of the transect (greater than 61 degrees S). Suspended particle sampling for trace element analysis and isotopic composition of Si For biogenic-Ba was also carried out. Typically 14 depths were sampled between the surface and 1000m. On board filtration was performed on Nuclepore membranes. These were dried (60 degrees C) and stored for analysis in the shore-based lab. Occasionally, we also sampled large particles - size fractions (greater than 70 micro m and 20 less than 70 micro m) - from the upper 150m for Ba, using the bow pump system of Tom Trull. Ba and Sr incubations on large settling particles sampled with the Snatcher were also performed at 5 particle stations. For delta30Si, all 24 depths of the deep CTD casts at the particle stations 1 to 8 were sampled. Filtered seawater and suspended matter filtered on Nuclepore membranes (dried at 60 degrees C) were saved for later analysis in the home based laboratory. 234Th work - we refer to the report by Ken Buesseler for the major part of this work. In addition we performed some work using the 'Snatcher' Large Volume sampler and sedimentation column. Total 234Th deficit and 234Th activity on particles and solution was assessed at T0 and T4 H after return of the sampling device on board, in an attempt to construct the 234Th mass balance and eventually get at the settling speed (and flux) of 234Th carrying particles. These analyses went together with flow cytometry analyses (collaboration with Clive Crossley) to check for sedimentation by (fluorescent) particles and also with POC and biogenic silica in order to determine the elemental ratios of suspended and sinking particles. Flow cytometer results did not indicate there was significant sedimentation of life cells going on at this time of the year. Dissolved Ba Seawater samples were taken at all depths sampled by deep CTD's during the southward transect. Samples were acidified and kept for later analysis of dissolved barium by isotope dilution ICP-MS. Comparison of the dissolved Ba distribution along the transect with the one reconstructed through a multiple end-member mixing model will help understanding of the relative contribution of in-situ processes (uptake, dissolution) versus conservative mixing, thus improving our understanding of the oceanic Ba biogeochemistry. Analysis New production. Isotope ratio analysis of the 15N and 13C spiked natural plankton samples will be conducted in the home lab., using emission spectrometry and mass spectrometry. Mass balance calculations will allow assessing relative importance of new production as well as the fraction of new production that is in the particulate form and represents the potential for export. Ba and trace elements. Suspended matter samples will be acid digested (HNO3, HCl, HF) and analysed per ICP-MS and ICP-AES for contents of Ba, Ca, Sr, Al, Fe, Mn, Th, U, REE, Ti. The vertical concentration profiles will inform on the latitudinal and temporal variability of the biogeochemical control processes between SAZ, PFZ, ACC and SSIZ subsystems. For the sites with sediment trap deployments, particulate trace element distributions in the water column will be compared with trace element composition of fast settling particles intercepted by the traps. Ba-uptake / barite formation. Isotope ratio analysis (135Ba/138Ba; 86Sr/87Sr) of suspended matter incubated after spiking with 135Ba and 86Sr will be analysed by ICP-MS to investigate on the barite formation process. Abundance and type of barite crystals will be studied by SEM-EMP (mapping + photographs). delta30Si, In the home based lab. particle samples will be extracted using base (NaOH). Silicates in filtered seawater will be precipitated and analysed using a multi collector ICP-sectorial Mass Spectrometer (MC-ICP-MS) once this new method is set up. 234Th. Total, particulate and dissolved 234Th measurements were performed on board using low beta counters. Background (after 6 months decay) and chemical yields will be measured at Ken Buesseler's lab (WHOI, USA), using beta counters and ICP-MS respectively. The worksheets contained in the excel spreadsheet are: Phyo biomass New production and cell counts Particulate barium Dissolved barium d29Si isotope signature of dissolved silicic acid The fields in this dataset are: Carbon Seawater CLIVAR temperature pressure salinity depth barium latitude longitude oxygen silicate phophate nitrate flagellates diatoms picoplankton plankton urea ammonia coccolithophores

Metadata record for data from ASAC Project 2720 See the link below for public details on this project. The overall objective is to characterize Southern Ocean marine ecosystems, their influence on carbon dioxide exchange with the atmosphere and the deep ocean, and their sensitivity to past and future global change including climate warming, ocean stratification, and ocean acidification from anthropogenic CO2 emissions. In particular we plan to take advantage of naturally-occurring, persistent, zonal variations in Southern Ocean primary production and biomass in the Australian Sector to investigate the effects of iron addition from natural sources, and CO2 addition from anthropogenic sources, on Southern Ocean plankton communities of differing initial structure and composition. These samples were collected on the SAZ-SENSE scientific voyage of the Australian Antarctic Program (Voyage 3 of the Aurora Australis, 2006-2007 season). SAZ-SENSE is a study of the sensitivity of Sub-Antarctic Zone waters to global change. A 32-day oceanographic voyage onboard Australia's ice-breaker Aurora Australis was undertaken in mid-summer (Jan 17 - Feb. 20) 2007 to examine microbial ecosystem structure and biogeochemical processes in SAZ waters west and east of Tasmania, and also in the Polar Frontal Zone south of the SAZ. The voyage brought together research teams from Australasia, Europe, and North America, and was led by the ACE CRC, CSIRO Marine and Atmospheric Research, and the Australian Antarctic Division. The overall goal is to understand the controls on Sub-Antarctic Zone productivity and carbon cycling, and to assess their sensitivity to climate change. The strategy is to compare low productivity waters west of Tasmania (areas with little phytoplankton) with higher productivity waters to the east, with a focus on the role of iron as a limiting micro-nutrient. The study also seeks to examine the effect of rising CO2 levels on phytoplankton - both via regional intercomparisons and incubation experiments. The data described in this metadata record are for seawater samples collected for HPLC pigments, microscopy and flow cytometry. Samples were collected either by Niskin Bottles (on a CTD), from the ocean surface with a bucket, or via a clean seawater line (at a depth of 7 metres), directly into the onboard laboratories. Samples for microscopy were examined either with an electron microscope, or a light microscope (lugol samples). The data are presented in an excel spreadsheet, available for download at the URL given below. The 'Notes' worksheet provides further information about the data contained in the spreadsheet, including a description of column headings, units used, etc. The fields used in this dataset are: Tube Label Site CTD Niskin bottle Depth (m) Date (UT) Start Time (UT) Stop Time (UT) Latitude Longitude Lugols Glutaraldehyde fixed samples Flow Coccolithophorids Volume HPLC Volume Turner Fluorometer reading (PAR) Photosynthetically Active Radiation Temperature (degrees C) Comment