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  • During the ADBEX III voyage, many samples were taken of the sea ice and snow. These samples were analysed to determine water density, with the results recorded in a physical note book that is archived at the Australian Antarctic Division. Logbook(s): - Glaciology ADBEX III Water Density Results - Glaciology ADBEX III Oxygen Isotope Sample Record

  • We collected surface seawater samples using trace clean 1L Nalgene bottles on the end of a long bamboo pole. We will analyse these samples for trace elements. Iron is the element of highest interest to our group. We will determine dissolved iron and total dissolvable iron concentrations. Samples collected from 7 sites: Sites 1, 2, 3, 4 were a transect perpendicular to the edge of the iceberg to try and determine if there is a iron concentration gradient relative to the iceberg. Sites 4, 5, 6 were along the edge of the iceberg to determine if there is any spatial variability along the iceberg edge. Site 7 was away from the iceberg to determine what the iron concentration is in the surrounding waters not influenced by the iceberg.

  • We checked each site by taking ice cores and observing the algae biomass to determine the likelihood of krill living under the sea ice in each location. We also used a Remotely Operated Vehicle (ROV) with cameras attached to observe the abundance of krill under the sea ice. If krill were present we used on the sea ice floe a zooplankton pump, called MASMA, according to Meyer et al. 2009, whereas at the edge of the floe column a custom-built fish pump system was used to collect krill near the surface. The Aqualife Biostream BP40 fish pump was capable of pumping up to 1300 litres per minute without harming animals that pass through the pump. For much of the voyage it was operated from the ctd room and at this increased suction head it ran at about 500 litres per minute. Krill were caught at ice stations 2, 6, 7 and 8. The Krill Sample-Overview.xls file contains information regarding how many krill were caught at each ice stations, who was involved and related information. The SIPEX II Krill Voyage Report.docx contains information about the various issues that were encountered during the voyage. It also contains information from the Bottom Krill experiment, which has its own dataset and metadata record. It is duplicated in both datasets. The larvae were used for a growth experiment using the IGR method and after length measurements frozen for carbon, nitrogen, lipids, stomach and gut content analysis. The total and carapace length were determined of juveniles as well as their digestive gland size. Animals were than dissected and tissues frozen at -80C for further analysis (see above). These condition parameters will be discussed in relation to physical and biological environmental parameters of the ice floe (e.g. sea ice thickness, snow coverage, under ice topography and biomass). When this data is analysed, the dataset will be updated to include analysed versions of the data listed in the Krill Sample-Overview.xls file. Also included in the dataset are technical documents and manuals pertaining to the fish pump that was used. Meyer B et al. 2009. Limnol Oceanogr 54:1595-1614

  • This dataset contains vertical profiles of particles in the upper water column (60 m depth) at six sites. A laser optical plankton counter (LOPC) was deployed through a hole in the sea ice, or from the stern of the Aurora Australis, and lowered to 60 m, logging as it was lowered. The LOPC records particles in the size range 100 um to 20 mm, though the small aperture (7 cm x 7 cm) means that the largest particles are probably only sampled rarely. For each site, the data are presented as normalised biomass for a series of equivalent spherical diameters (ESD). ESD is based on measurements of length and width of animals likely to be sampled via the LOPC (i.e. animals that are sampled at the same time with a traditional plankton net). The data were collected on the SIPEX II voyage of the Aurora Australis, from 14/9/2012 to 16/11/2012. Sites were all located in first year pack ice; the ship would nudge up to a floe and then samples of ice, zooplankton, etc. were collected directly by working on the floe. The LOPC was either deployed through a large hole in the pack ice, or it was deployed off the stern of the AA. Method of deployment did not really have an impact on the data collected, it was more a logistical decision based on conditions.

  • This dataset is a time series of sea ice freeboard proxy estimation based on ASCAT C-band backscatter measurements. File format is unformatted binary, with each file 632*664 pixels, and 32 bits per pixel (floating point). Two datasets are presented here, as detailed in University of Tasmania Honours thesis by Nicola Ramm: "unmasked", i.e., no attempt to mask multiyear and marginal sea ice, and "masked", where these are masked based on backscatter. The grid used by this dataset is described here: https://nsidc.org/data/polar-stereo/ps_grids.html The methods are described in an honours thesis by Nicola Ramm, University of Tasmania.

  • This record contains the source, gridded data used to produce the maps described in the metadata record with the ID "SIPEX_II_NAME". See the provided URL. The UK Met Office's Numerical Atmospheric-dispersion Modelling Environment (NAME) is used to model a wide range of atmospheric dispersion events. These data were collected during the SIPEX II voyage of the Aurora Australis, 2012. The use of NAME and the NWP met data was provided by the UK Met Office for free for research purposes. The analysed wind fields used for the running of NAME are calculated using the Met Office's Unified Model (UM). These are calculated by incorporating all observational site data at six hourly intervals into a forecasting system +/- 3 hours of the observation time. This is continuously repeated to produce a 3D analysis of the state of the atmosphere defined by meteorological variables. It is these variables that are incorporated into NAME and are used to calculate wind vectors, particle position, etc. The global resolution for these fields is 25 km. Model Descriptor Inert particles released for two hours each day between 01:00 - 03:00. The lat/lon for the ship was taken at 02:00 every day. The particles were tracked backwards in time for ten days. The NAME output grid comprised of 267 by 165 boxes of 0.5652 degrees longitude and 0.375 degrees latitude. The lat/lon minimum was 60.0,-85.0 and the max was 210,-23. The plots show the daily particle densities in g s m-3 per grid box for the whole of the back run. There are four different types of plots showing surface influence (0-100m), whole troposphere influence (0-16000m) and below the avg boundary layer (BL). The BL heights have also been plotted at the time of release for each of the backruns.

  • This dataset will be comprised of measurements taken from trace metal water column samples collected during the SIPEX II Antarctic marine science voyage in 2012. In its current form no sample analysis has been performed. The dataset simply contains the log sheets for the Trace Metals Rosette (TMR) deployments as well as the output files from the TMR software (General Oceanics). Water samples for dissolved trace metal measurements were collected from the surface (15m) down to the 1000m using an autonomous intelligent rosette system (General Oceanics, USA) specially adapted for trace metal work and deployed on a Dyneema rope. The rosette was equipped with 12x10-L Niskin-1010X bottles specially modified for trace metal water sampling. This system has been successfully deployed on the RSV Aurora Australis during voyages au0703 and au0806. Care was taken to avoid any contamination from the ship and the operating personnel. Water samplers were processed aboard under an ISO class 5 trace-metal-clean laminar flow bench in to a trace-metal-clean laboratory container on the ship's trawl deck. All transfer tubes, filtering devices and sample containers were rinsed liberally with sample before final collection. Samples were then drawn through C-Flex tubing (Cole Parmer) and filtered in-line through 0.2 micron pore-size acid-washed capsules (Pall Supor membrane, Acropak 200). Filtered and unfiltered samples were collected in acid-cleaned 125ml Nalgene LDPE bottles for analysis of dissolved trace metals. Samples were also collected for the determination of stable isotopes of nitrogen and carbon. As well, filtered samples were taken for macro-nutrient analysis in the lab (2 small vials per Niskin, frozen). Regular sampling depths were as follows: 1000m, 750m, 500m, 300m, 200m, 150m, 125m, 100m, 75m, 50m, 30m, 15m. At a subset of the SIPEX II ice stations, filtered samples were also collected for Iron(II) analysis aboard the ship by Christina Schallenberg (in the trace-metal-clean laboratory container), and unfiltered samples were collected for analysis of mercury and methyl-mercury by Caitlin Gionfriddo (caitlingio@gmail.com).

  • Instrument description: Gaseous elemental mercury (GEM) was measured at five minute intervals. GEM was collected and analysed on two parallel gold traps. While GEM was collected on one gold trap, the mercury on the other traps was simultaneously being thermally desorbed and detected by a cold vapour atomic fluorescence spectrometer. The Tekran was calibrated approximately every 24 - 48 hours using an internal Hg permeation source. The internal calibration source was checked prior to shipping the instrument to Australia using an external Hg source. The internal calibration source will be verified upon return of the instrument. Instrument Setup: This instrument was sampling from a weather protected inlet positioned ~3 m off the front port side of the Monkey Deck of the Aurora Australis, directly above the bridge. The 35m heated Teflon sample line end and filter is contained within the "Ned Kelly", a large (~30 cm diameter) stainless steel can which protects against rain, snow, sea spray and major impacts. This sample line ran 25m down to the Tekran instrument which was located in a the Met-Lab. Ar (99.999% purity) was fed into the MetLab via quarter inch Teflon tubing from the oxygen store on the Monkey deck. A 2D R.M. Young (model 5305-AQ) anemometer was also deployed at the same elevation on the aft side of the sample inlet. The anemometer was oriented with zero degrees pointed directly forward of the ship. Mean Wind speed and direction were captured using Campbell Scientific CR1000 datalogger at five-minute intervals. The files included in this dataset are the raw outputs from the Tekran 2537. They include headers, though not always at the top of the file, because headers are only written when the instrument is started or after recalibration. Also included are scanned log books containing meteorological observations, maintenance notes, and when adjustments were made to the sample line (which alters anemometer data).

  • This dataset is a climatological summer chlorophyll-a layer for the Southern Ocean south of 40S, following the OC3M algorithm of Johnson et al. (2013). The climatology was calculated from level-3 binned MODISA RRS products spanning the 2002/03 to 2015/16 austral summer seasons (summer taken as day 355 to day 80).

  • This dataset contains data resulting from the measurement of brine samples extracted from the sea-ice during the 2012 SIPEX 2 (Sea Ice Physics and Ecosystems Experiment) marine science voyage. The Brine was collected from partially drilled holes in the ice using suction. In some of these cases the brine analysed came from holes which correspond to permeability measurements. In these cases a core number is associated with the brine data which will correspond to the core number in the permeability data set found in the master core list Excel file. The purpose of this data set was to act as a first step to quantify the effect that extra cellular carbon may have on the physical properties of brine and sea ice. At least 1 litre of brine was collected from each partial hole for analysis. The total sample was split for the following analyses. Viscosity of the brine was measured before and after filtering out any biological components that may have been in solution or otherwise in order to assess whether or not extracellular carbon has an effect on fluid flow in sea ice. What was not used for viscosity measurements was used for chlorophyll, extra-cellular carbon and bacterial analysis to gain a sense of the level and type of biology and biological compounds in the brine to then be compared to the measured physical properties. The biological analysis will be carried out at the university of Tasmania by Sarah Ugalde. On many of these samples the complex permittivity of the brine was also measured and the data can be found in the Relative_Permitivity_of_Brine folder with each sample corresponding in core number. For info on the permittivity measurements please see the metadata in that folder.