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    Temperature loggers have been deployed at a range of sites statewide in waters ranging between 6 and 22m depth. From 2012, 27 sites around Tasmania are being monitored. This record shows data collected from 2004 up to December 2020. Data is still being collected (April 2023) and will be added to this collection as it becomes available.

  • This parameter set was developed to provide a plausible implementation for the ecological model described in Bates, M., S Bengtson Nash, D.W. Hawker, J. Norbury, J.S. Stark and R. A. Cropp. 2015. Construction of a trophically complex near-shore Antarctic food web model using the Conservative Normal framework with structural coexistence. Journal of Marine Systems. 145: 1-14. The ecosystem model used in this paper was designed to have the property of structural coexistence. This means that the functional forms used to describe population interactions in the equations were chosen to ensure that the boundary eigenvalues of every population were all always positive, ensuring that no population in the model can ever become extinct. This property is appropriate for models such as this that are implemented to model typical seasonal variations rather than changes over time. The actual parameter values were determined by searching a parameter space for parameter sets that resulted in a plausible distribution of biomass among the trophic levels. The search was implemented using the Boundary Eigenvalue Nudging - Genetic Algorithm (BENGA) method and was constrained by measured values where these were available. This parameter set is provided as an indicative set that is appropriate for studying the partitioning of Persistent Organic Pollutants in coastal Antarctic ecosystems. It should not be used for predictive population modelling without independent calibration and validation.

  • This dataset contains albedo data for several varieties of sea ice and snow from 300-2500 nm measured during the SIPEX II voyage (2012). An Analytical Spectral Device (ASD) spectrophotometer records the amount of radiation impingent on a cosine collector, which contains a spectralon diffuser plate. The radiation that hits the diffuser plate is scattered equally in all directions (isotropically). A portion of the radiation incident on the plate is scattered in the direction of a fiber optic cable, which is connected to the ASD. The ASD separates the incoming radiation into 3-10 nm wavelength bins, thus creating a radiation spectrum spanning 300-2500 nm. The cosine collector can be oriented both upwards towards the sky and downward towards the snow and/or sea ice to measure the spectral signature of both the downwelling (from the sky) and upwelling (from the snow/ice) radiation. For each site, we record 5 upwelling and 5 downwelling spectral signatures. MATLAB or a similar analysis package is required to open the spectrum files that are created by the ASD. The ASD files are raw files and named in a sequence, starting with 'spectrum.000'. MATLAB or similar scripts can been written to convert the ASD spectrum data to .mat files. The spectra in the processed files are used to calculate the albedos for various snow and ice types when the ratio of upwelling to downwelling radiation is computed. We use two upwelling scans per one downwelling scan to compute the albedo. Also included is some photography of frost flowers and other examples of ice that was observed.

  • This project monitored plastics at the four-bays area on Heard Island and at Sandell Bay on Macquarie Island. It characterised plastics by infra-red spectroscopy both from the beach collection and small pieces from fur-seal stomachs and cormorant boluses. The aim was to assess human impact on the ocean by measuring plastic abundance and type.

  • This work was completed as part of the SIPEX - Sea Ice Physics and Ecosystem eXperiment - voyage. Adapted from the SIPEX website: During SIPEX we investigated the biogeochemistry of iron (Fe), including a comprehensive examination of its distribution, speciation (i.e. the different forms of Fe), cycling and its role in fuelling sea ice-based and pelagic algal communities. A major part of this research concentrated on the influence of organic exopolysaccharides (EPS) on Fe solubility and its bio-availability. The distribution of other bioactive trace elements was also examined as a means of fingerprinting the source(s) of Fe, as well as indicating their biological requirements. ######### Data on the small- to medium scale (0.1-1000 m) spatial and temporal distribution of Fe and EPS in sea ice cores, surface snow, brine and underlying seawater were determined in each sampled medium by the interdisciplinary team working on the SIPEX project (AAS 3026) in the East Antarctic sector in September/October 2007. Data include Chlorophyll a, salinity, temperature, sea-ice thickness, ice texture analysis, macro-nutrients (nitrate, phosphate, silicate), oxygen stable isotopes, POC and DOC, EPS, iron. This work was completed as part of AAS (ASAC) project 3026. See the parent metadata record (ASAC_3026) for more information.

  • Untreated, macerated wastewater effluent has been discharged to the sea at Davis Station since 2005, when the old wastewater treatment infrastructure was removed. This environmental assessment was instigated to guide the choice of the most suitable wastewater treatment facility at Davis. The assessment will support decisions that enable Australia to meet the standards set for the discharge of wastewaters in Antarctica in national legislation (Waste Management Regulations of the Antarctic Treaty Environmental Protection Act - ATEP) and to meet international commitments (the Madrid Protocol) and to meet Australia's aspirations to be a leader in Antarctic environmental protection. The overall objective was to provide environmental information in support of an operational infrastructure project to upgrade wastewater treatment at Davis. This information is required to ensure that the upgrade satisfies national legislation (ATEP/Waste Management Regulations), international commitments (the Madrid Protocol) and maintain the AAD's status as an international leader in environmental management. The specific objectives were to: 1. Wastewater properties: Determine the properties of discharged wastewater (contaminant levels, toxicity, microbiological hazards) as the basis for recommendations on the required level of treatment and provide further consideration of what might constitute adequate dilution and dispersal for discharge to the nearshore marine environment 2. Dispersal and dilution characteristics of marine environment: Assess the dispersing characteristics of the immediate nearshore marine environment in the vicinity of Davis Station to determine whether conditions at the existing site of effluent discharge are adequate to meet the ATEP requirement of initial dilution and rapid dispersal. 3. Environmental impacts: Describe the nature and extent of impacts to the marine environment associated with present wastewater discharge practices at Davis and determine whether wastewater discharge practices have adversely affected the local environment. 4. Evaluate treatment options: Evaluate the different levels of treatment required to mitigate and/or prevent various environmental impacts and reduce environmental risks.

  • Direct Numerical Simulations are carried out at the ice ocean interface of 1.8 m long, inclined at angles, 50 degree, 65 degree and 90 degree from the horizontal where external source buoyancy is added as a boundary conditions with relative buoyancy B* 5, 7 and 10 times the wall buoyancy. The data set contains 1. Time averaged temperature, salinity and velocity fields of the flow at steady state where averaging windows are several times the respective buoyancy frequency for 90 degree, B* =1, 5,7,10; 50 degree, B*=1, 5, 7 respectively. 2. Tabulated, time averaged along-slope profiles of a) temperature, b) salinity, c) meltrate, d) plume velocity for 90 degree, B* =1, 5,7,10; 65 degree, B* =1, 5,7,10 and 50 degree, B*=1, 5, 7 respectively. 3. Tabulated, domain averaged meltrate, plume velocity for 90 degree, B* =1,3, 5,7,10; 65 degree, B* =1,3, 5,7,10 and 50 degree, B*=1,3, 5, 7 respectively.

  • Gas Flux over Sea Ice ------------- We observed amount of gas exchange between sea ice and atmosphere. At the ice station, semi-automated chambers developed in Japan, were used for measurement of air-sea ice CO2 flux. These chambers could be used to examine spatial variability and also temporal variability of gas flux over sea ice. Samples were also taken from the snow and ice in order to measure CH4 and VOC, however these analyses will be conducted post-voyage. This metadata record will be updated in future to reflect the analysis. The chambers are designed to be placed over a snow and sea ice. When the lid is closed, CO2 concentration was measured. The opening and closing functions of the chambers are automated and were set to a 30 minutes interval. CO2 concentration (as voltage) were recorded in the data logger (CR10X, Campbell Scientific Inc.) and downloaded after the experiments. Raw data are contained in the excel files. During the CO2 flux measurement, we collected the snow, sea ice, brine/slush and under-ice water. Snow and sea ice samples were melted after sampling in PVDF film bags (like Tedlar bags in order to avoid gas exchange with ambient air) in 4C temperature and treated for analysis. A chemical analysis for carbonate systems and VOC (water), salinity, nutrient, pigment and oxygen isotopic ratio samples will take place in Japan after the voyage for analysis. During the cruise, to examine ice growth processes, we made sea ice thin-section to classify the ice cores into granular ice, columnar ice or mixed granular and columnar ice (Eicken and Lange, 1989). The CO2 data are contained in Excel spreadsheets. These use Japanese column headings. Calcium Carbonate (CACO3.6H20) as Ikaite in Sea Ice and Snow ----------- At each listed ice station we collected sea-ice cores using a Kovacs 9cm ice corer. Cores were sectioned into 10-20cm and melted at 4 degrees C, filtered and dried for later analysis of Calcium Carbonate in a home laboratory using an ICP, which produces text file outputs (included). Also included is a spreadsheet listing the cores, and the calcium carbonate measurements.

  • This data set provides the organochlorine content found in four sea-ice samples collected in the vicinity of Davis station over a three week period in 2014/15. Sea-ice is thought to serve as a reservoir for organochlorine pesticides during the winter. The aim of the study was to investigate the movement of organochlorine pesticides in the seasonal sea-ice during ice melt. A custom made, closed-system, ice melting unit, coupled to an in-situ water filter, was implemented for sampling. Minimal ice-melt or change in organchlorine content was found over the three week period. Changes were attributed to high ventilation of the sea-ice surface caused by high wind speeds found in the Antarctic compared to the Arctic. 4 sea-ice samples were collected in the vicinity of Davis station and contaminant profiles extracted and analysed. Caution should be taken in interpretation of data as the ice/water extraction unit failed during operation.

  • Metadata record for data from ASAC Project 2665 See the link below for public details on this project. The Antarctic environment with its harsh climatic conditions, minimal human activity and its unique ecosystems is unlike any of the World's other environments. As such, it is important that an understanding of the Antarctic environment is developed in order to gain a full appreciation of the impacts of human activities in Antarctica and to determine the most effective means to remediate and protect the Antarctic environment. To achieve these goals, new sensitive and selective techniques for sampling metal contaminant levels in marine sediments are being developed. The project is not an environmental study of the Antarctic environment (ie no metal concentrations in water or sediments), but rather the development of an analytical technique for use in Antarctica. We are still in the process of developing this technique and much of the development phase has involved qualitative assessment rather than generating quantitative data. We are currently trialling the technique in the lab and will conduct field trials in the Derwent Estuary. Taken from the abstract of the referenced paper: A novel binding phase was developed for use in diffusive gradients in thin-film (DGT) sampling for Cu(II) by employing methylthymol blue as a chelating and chromogenic agent. Methylthymol blue was adsorbed onto beads of Dowex 1x8 resin (200-400 mesh) and the resin beads were then immobilised onto an adhesive disc. Analysis of exposed binding discs by either UV-vis spectrophotometry or computer imaging densitometry provided robust quantification of adsorbed Cu(II) in the 0.2-1 micro gcm-2 range, allowing detection at micro gL-1 concentrations in the test solution (ca. 17 micro gL-1 for a 24 h deployment), and in good agreement with established DGT theory. The method was shown to be a potential replacement for binding phases based on Chelex 100 where a colorimetric response to a specific metal is desired.