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  • Bathymetric Contours and height range polygons of approaches to Casey Station, derived from RAN Fair sheet, Aurora Australis and GEBCO soundings.

  • Metadata record for data from ASAC Project 2385 See the link below for public details on this project. ---- Public Summary from Project ---- Facilities for chemical analysis of environmental samples in Antarctica are limited, with samples frequently shipped at great expense to Australia for analysis. Development of a technique to concentrate metals from environmental samples into a thin film which can be easily transported to a laboratory for analysis is currently underway. DGT stands for Diffusive gradients in thin films, they are a passive sampling technique for trace metals based on Fick's First Law of diffusion. Basically the theory being the method: Zhang, H. and Davison, W., Anal Chem, 1995, 67, 3391-400 and Davison, W. and Zhang, H., Nature (London), 1994, 367, 546-8. Description of spreadsheets: All data were collected using DGT sediment probes or water samplers prepared from polyacrylamide diffusion layer (0.8 mm thickness, covered with a 0.13 mm thick membrane filter) and Chelex 100 binding layer (0.4 mm thick). Metadata 0304 sediment - DGT sediment probes were deployed during the 0304 summer. Samples were deployed in a 3 x 2 back-to-back array at the inner and outer sites in Brown and O'Brien Bay. ie 1.1 and 1.2 are back to back pair. All samplers were deployed for 34 days. More accurate date are on the attached s'sheet. Results shown are nanograms of metals per square centimetre accumulated in the samplers at a resolution of 2 cm. The detection limits of the metals for the samplers are based on 3 x stdev of the field blank probes. Where value = &nd& the value was less than the method detection limit. Metadata 0304 sediment Characterisation - Cores were sampled in Dec 2003 - Jan 2004 from Casey Station region. All characterisation was performed on the same 1 cm slices of core. Cores were sampled and analysed in anoxic conditions. Latitudes and Longitudess Brown Bay inner66.2803 S, 110.5414 E Brown Bay outer66.2802 S, 110.5451 E O'Brien Bay inner66.3122 S, 110.5147 E O'Brien Bay outer66.3113 S, 110.5162 E Metadata 0203 sediment - Results shown are sediment profile in nanograms of metals per square centimetre accumulated in the samplers at a resolution of 1 m. Samples 1.x were deployed for 5 days before the summer melt, 2.x were deployed for 10 days before the melt, 3.x were deployed for 15 days before the melt, 4.x were deployed for 21 days before the melt, 5.x were deployed for 28 days before the melt, 6.x were deployed for 5 days during the melt and 7.x were deployed for 20 days during the melt. The detection limits of the metals for the samplers are based on 3 x stdev of the field blank probes. Where value = 'nd' the value was less than the method detection limit. Metadata 0304 water - Results show metals in DGT water samplers deployed for 28 days. Actual times are on spreadsheet attached. Samplers were deployed in triplicate at three depths in the water column, with the depth from the sed bed meaning metres above the sea bed in the water column. Values in the original spreadsheet is nanograms of metals accumulated in sampler of 3.14cm2 area. The detection limits of the metals for the samplers are based on 3 x stdev of the field blank. Where value = 'nd' the value was less than the method detection limit. Metadata 0203 water - Results show metals in DGT water samplers deployed for 8 days. Samplers were deployed in triplicate at three depths in the water column. Depth from seabed is a measure of distance from the sea bed to the deployment depth in the water column. Values in the original spreadsheet is nanograms of metals accumulated in sampler of 3.14cm2 area. The detection limits of the metals for the samplers are based on 3 x stdev of the field blank. Where value = 'nd' the value was less than the method detection limit. ---- One thing to note, although the metal isotopes are listed, ie Cd111(LR), this is still a measure of the elemental Cd (ie all isotopes), it is just how the ICP-MS analyst presents the data when I get the raw data back. I probably should have corrected this by remove the number to remove any ambiguity involved. A pdf file of supplementary figures created from the raw data are also included as a download file. Explanations of the figures are presented below. Supplementary Data Figure Captions Figure S1. 2002 - 03 DGT water sampling results for Cd, Fe and Ni, before the melt (upper) and during the melt (lower). BB Brown Bay, OBB O'Brien Bay, top top depth, mid middle depth, bot bottom depth. Error bars represent minimum and maximum values based on three replicates and horizontal line is the detection limit based on 3s Figure S2. 2002 - 03 DGT uptake results for Mn, Fe and As in Brown Bay (upper) and O'Brien Bay (lower) for various deployment times Figure S3. 2003 - 04 DGT sediment probes results for Brown Bay outer. Upper axis represents maximum porewater concentration assuming no resupply; symbols are for 6 replicate DGT probes. Detection limit, based on 3s is represented by vertical line Figure S4. 2003 - 04 DGT sediment probes results for O'Brien Bay inner. Upper axis represents maximum porewater concentration assuming no resupply; symbols are for 6 replicate DGT probes. Detection limit, based on 3s is represented by vertical line Figure S5. 2003 - 04 DGT sediment probes results for O'Brien Bay outer. Upper axis represents maximum porewater concentration assuming no resupply; symbols are for 6 replicate DGT probes. Detection limit, based on 3s is represented by vertical line Figure S6. Sediment porewater concentrations from replicate Brown Bay outer cores Figure S7. Sediment porewater concentrations for O'Brien Bay inner (open circles) and outer (closed circles)

  • The concentration of heavy metals in seawater at four sites around Casey was determined via Diffusive Gradients in Thin films (DGT) loggers attached to experimental mesocosms suspended below the sea ice. Data are the concentration of heavy metals in micrograms per litre (ug/l), equivalent to parts per billion (ppb)/litre Two loggers were attached to each mesocosm (perforated 20 litre food buckets) at each site; one at the top and one at the bottom of each mesocosm. Mesocosms were suspended two to three metres below the bottom edge of the sea ice through a 1 metre diameter hole and were periodically raised to the surface for short periods (~1 hour). This experiment was part of the short-term biomonitoring program for the Thala Valley Tip Clean-up at Casey during summer 2003/04. During Runs 1 and 2 of the experiment mesocosms were deployed at Brown Bay Inner (S66 16.811 E110 32.475), Brown Bay Outer (S66 16.811 E110 32.526), McGrady Cove (S66 16.556 E110 34.392) and O'Brien Bay 1 (S66 18.730 E110 30.810). In Run 3 mesocosm were deployed in open water with no sea ice covering at Brown Bay Inner (S66 16.807 E110 32.556), Brown Bay Outer (S66 16.805 E110 32.607), McGrady Cove (S66 16.520 E110 34.257) and O'Brien Bay (S66 17.607 E110 31.247). These data were collected as part of ASAC project 2201 (ASAC_2201 - Natural variability and human induced change in Antarctic nearshore marine benthic communities). See also other metadata records by Glenn Johnstone for related information.

  • The salinity of seawater at four sites around Casey was recorded during summer 2003/04 by a salinity probe (TPS Australia, WP-84 Conductivity Meter) attached to experimental mesocosms suspended below the sea ice. Data are salinity in parts per thousand (ppk) automatically logged every 30 minutes over the two two week long runs of the experiment. The period over which data were recorded varies between sites and is fragmentary within these periods at some sites due to power lose to the loggers caused by faulty batteries and adverse weather conditions. Mesocosms were suspended two to three metres below the bottom edge of the sea ice through a 1 metre diameter hole and were periodically raised to the surface for short periods (~1 hour). Mesocosms were deployed at Brown Bay Inner (S66 16.811 E110 32.475), Brown Bay Outer (S66 16.811 E110 32.526), McGrady Cove (S66 16.556 E110 34.392) and O'Brien Bay 1 (S66 18.730 E110 30.810). This experiment was part of the short-term biomonitoring program for the Thala Valley Tip Clean-up at Casey during summer 2003/04. These data were collected as part of ASAC project 2201 (ASAC_2201 - Natural variability and human induced change in Antarctic nearshore marine benthic communities). See also other metadata records by Glenn Johnstone for related information.

  • Two 16S rDNA clone libraries, one from a Brown Bay sample and one from an O'Brien Bay sample were generated. These samples were originally collected as part of ASAC project 868 and the microbiology of the samples is now being investigated as part of ASAC 1228. Two data files are included in the download. Both are in "fasta" format, a text-based format for representing either nucleotide sequences or peptide sequences, in which base pairs or amino acids are represented using single-letter codes. Further information about the dataset can also be found in the referenced paper.

  • This dataset contains records of ice thickness and snow thickness from Casey, Antarctica. Measurements were attempted on a weekly basis and were recorded between 1979 and 1992. The observations are not continuous however. The dataset is available via the provided URL. This data were also collected as part of ASAC projects 189 and 741. The Casey fast ice thickness data are no longer being collected.

  • Metadata record for data from ASAC Project 2518 See the link below for public details on this project. Global climate change will lead to a reduction in the duration and thickness of sea ice in coastal areas. We will determine whether this will lead to a decrease in primary production and food value to higher predators. Project objectives: Our primary objective is to determine what effect will declining sea ice cover have on Antarctic coastal primary production? Hypotheses to be tested - A decrease in sea ice algal production will lead to a net reduction in total primary production. - A decrease in sea ice will result in less water column stratification which will reduce the significance of phytoplankton blooms. - Less sea ice will lead to a change in phytoplankton bloom composition away from diatoms towards un-nutritious nuisance blooms such as Phaeocystis - Benthic microalgal production will increase - Seaweed production will increase slightly - A decrease in sea ice thickness will increase ice algal production (as they are generally light limited) - Ice algae, benthic microalgae, and phytoplankton will acclimate to an elevated light climates by changing their photosynthetic efficiency and capacity - Ice algae, benthic microalgae, and phytoplankton will acclimate to an altered light quality. To answer these questions we will also need to determine: - What is the total annual primary production at coastal Antarctic sites; this consists of the contributions from the sea ice algal mats, benthic microalgal, seaweed and phytoplankton? - What is the effect of major environmental variables, such as UV, salinity, currents oxygen toxicity, cloud cover, nutrient availability and temperature on production. - What is the inter-annual variability in primary production? A broader scale issue that our data will contribute to providing answers to is the question - What effect will changing primary production have on higher trophic levels? Taken from the 2009-2010 Progress Report: Progress against objectives: The 2009/10 field and laboratory season focused on the second of our primary questions, i.e. 'What is the effect of major environmental variables, such as UV, salinity, currents oxygen toxicity, cloud cover, nutrient availability and temperature on production'. In particular we focused on light and light transmission though the sea ice. The science program AAS2518 was executed at Casey station from 11 Nov to 5 Dec 2009. The project was split into a field and a lab-based component. In situ spectral light transmission data were collected on first year sea ice within the vicinity of Jack's Hut. Ice cores were collected and transported to the laboratory at Casey station for spectral attenuation profiles within sea ice, and for measurements of spectral absorption by particulate and dissolved organic matter. Overall, the program was successful: in situ sea-ice spectral transmission data was collected in combination with vertical profiles of absorption coefficients of particulate (algae and detritus) and dissolved organic matter. Samples for analysis of photosynthetic pigments were collected and shipped to Sydney. Their analysis is underway. Due to logistical issues associated with the collection and transport of sea ice cores, the protocol for vertical profiling of spectral attenuation was modified (see below) and analysis of the data is currently underway. The field component of the program was successful as spectral transmission data was collected for first year sea-ice, and the chosen site contained a thriving sea ice algal community for bio-optical measurements. It was initially planned to sample multiple sites offering a range of varying sea-ice thickness, but this was not possible during this campaign. Many sites in the vicinity of Casey station had already started to melt and break up, so that for logistical and safety reasons the area around Jack's hut was the only workable option. The field period instead spanned ~ 20 days during the melt period at Jack's, during which the porosity of sea ice increased but thickness remained constant. Ice cores destined for spectral transmission profiles were to be collected whole and intact, but due to the presence of fractures in the sea ice, drilling (manual as well as motor powered) resulted in fractured core samples. The protocol was therefore modified: cores were sectioned in 20 cm sections and spectral transmission measured for each section. Spectral transmission profiles across the entire thickness of sea ice are to be re-constructed from the discrete data points. The accuracy of the approach will be assessed against the in situ spectral transmission data. The download file contains three spreadsheets (two of them are csv files), and a readme document which provides detailed information about the three spreadsheets.

  • This metadata record will contain the results of analyses of tissue samples from Antarctic Rock-cod (Trematomus bernacchii) collected at sites around Davis station to determine wastewater exposure and sub-lethal impact. AAS Project 4177. The results of metal analysis, stable isotope analysis and images of histological analysis of fish from Davis Station are in this dataset. Sample sites and fish collection Antarctic Rock-cod were collected at 6 sites from Prydz Bay near Davis Station East Antarctica, during the 2012/13 summer. Approximately twenty fish were collected from each site by line and in box traps from four sites along a (9 km) spatial gradient starting from the Davis Station wastewater outfall, southward 0km (within 250m of the point of discharge), 1km, 4km and 9km, in the direction of the predominant current. Additionally, two reference sites were sampled 9 km and 16 km north of the discharge point. Once collected, fish were immediately returned to the Davis Station laboratories and sacrificed individually by immersion in an Aqui-s solution (~15ml/L). Once no signs of life were present (approximately 5 min), fish length and weight were measured. Tissues were preserved in various ways for a number of analyses to be conducted at a later date. Stable Isotope analysis. Davis Station Laboratory Dorsolateral muscle tissue from the left side of each individual was removed, placed in aluminium foil and frozen at -20 degrees C for later analysis. Tissue processing A section of frozen tissue was removed (approximately 1 x 1 cm cubed), placed into a clean, acid washed glass crucible and cut into small pieces. This was then dried at 80 degrees C for 48 h. Tissue from each fish was carefully removed and placed into separate 2 ml Eppendorf tubes, each containing an washed, dried stainless steel ball bearing and the lids closed tightly to ensure no moisture could enter. Tissue was crushed into a fine powder by shaking in a Tissue II Lyser. Ball bearings were removed from vials and crushed tissue samples were sent to Cornell University Stable Isotope laboratory for d13C (carbon stable isotope) and d15N (nitrogen stable isotope) analysis. Stable isotope ratios are expressed in parts per thousand units using the standard delta (d) notation d13C and d15N. Data Set This data set consists of an Excel spreadsheet containing raw data of Nitrogen and Carbon Stable Isotope analysis from 6 sites in the Prydz Bay area of East Antarctica. It includes site distance and direction from wastewater discharge point. The file name code stable isotope analysis is; Project number_Season_Taxa_analysis type AAS_4177_12_13_Trematomus_Isotopes Project number : AAS_4177 Season : 2012/13 season Taxa: Trematomus Analysis type: Stable Isotope Metal analysis. Davis Station Laboratory Dorsolateral muscle tissue from the right side of each individual was removed, placed in a plastic zip lock bag and frozen at -20 degrees C for later analysis. Tissue processing 10g of frozen muscle tissue was sent to Advanced Analytical Australia for metal analysis of a suite of metals (Cd, Cr, Cu, Hg, Mn, Zn, Al, Ni, Pb). Data Set This data set consists of an Excel spreadsheet containing raw data of metal analysis (mg/kg) from 6 sites in the Prydz Bay area of East Antarctica. It includes site distance and direction from wastewater discharge point. The file name code stable isotope analysis is; Project number_Season_Taxa_analysis type AAS_4177_12_13_Trematomus_Metals Project number : AAS_4177 Season : 2012/13 season Taxa: Trematomus Analysis type: Metal analysis Histological analysis Davis Station Laboratory A small piece of a number of fish tissues (gill, liver, spleen, head kidney, gonad), were collected immediately after death of the fish to ensure no degradation of tissue and preserved in 10% seawater buffered formalin for later analysis Tissue processing Each piece of tissue was dehydrated in ascending grades of ethanol (30-100%), cleared in Histolene and embedded in paraffin wax. Tissue was sectioned using a HM 32 Micron microtome at 4 microns. Standard haematoxylin and eosin (H and E) stain was used to stain all tissue sections. Each section was examined blind (i.e. the examiner did not know the field location of the tissue samples) using a Zeiss AxioPlan microscope at 100-400 x magnification. Histological analysis is ongoing. Data Set This data set consists of a pdf file with images of normal and potential sub-lethal histological alterations. The file name code stable isotope analysis is; Project number_Season_Taxa_analysis type AAS_4177_12_13_Trematomus_Histology Project number : AAS_4177 Season : 2012/13 season Taxa: Trematomus Analysis type: Histopathology

  • Project 565: The database provides a list of species of ciliates and testate amoebae (Protozoa: Ciliophora; Testacea) recorded in various edaphic habitats, e.g., mineral soils (fellfield), ornithogenic soils, terrestrial mosses, from ice-free coastal areas and inshore islands in the area of Casey Station, Wilkes Land, coastal continental Antarctica. 26 ciliate (9 first records for continental Antarctica, 1 undescribed) and 5 testacean species (3 new records) were found. Sea ice study (Weddell Sea): The ciliate biodivesity was studied in several types of sea ice (mainly young pancake ice) from the Weddell Sea, Antarctica, in the austral autumn 1992 (March-May) during the cruise ANT X/3 of RV Polarstern. 49 ciliate species were predominantly found in sea ice and 6 spp. in the pelagial; 20 of these were new to science. A word document containing a list of species that were recorded as part of the project is available for download from the provided URL. These data have also been incorporated into the biodiversity database.

  • This indicator is no longer maintained, and is considered OBSOLETE. INDICATOR DEFINITION Regular measurements of the thickness of the fast ice, and of the snow cover that forms on it, are made through drilled holes at several sites near both Mawson and Davis. TYPE OF INDICATOR There are three types of indicators used in this report: 1.Describes the CONDITION of important elements of a system; 2.Show the extent of the major PRESSURES exerted on a system; 3.Determine RESPONSES to either condition or changes in the condition of a system. This indicator is one of: CONDITION RATIONALE FOR INDICATOR SELECTION Each season around the end of March, the ocean surface around Antarctica freezes to form sea ice. Close to the coast in some regions (e.g. near Mawson and Davis stations) this ice remains fastened to the land throughout the winter and is called fast ice. The thickness and growth rate of fast ice are determined purely by energy exchanges at the air-ice and ice-water interfaces. This contrasts with moving pack ice where deformational processes of rafting and ridging also determine the ice thickness. The maximum thickness that the fast ice reaches, and the date on which it reaches that maximum, represent an integration of the atmospheric and oceanic conditions. Changes in ice thickness represent changes in either oceanic or atmospheric heat transfer. Thicker fast ice reflects either a decrease in air temperature or decreasing oceanic heat flux. These effects can be extrapolated to encompass large-scale ocean-atmosphere processes and potentially, global climate change. DESIGN AND STRATEGY FOR INDICATOR MONITORING PROGRAM Spatial Scale: At sites near Australian Antarctic continental stations: Davis; Mawson. Frequency: at least weekly, reported annually Measurement Technique: Tape measurements through freshly drilled 5 cm diameter holes in the ice at marked sites. RESEARCH ISSUES To more effectively analyse the changes in Antarctic fast ice a detailed long-term dataset of sea ice conditions needs to be established. This would provide a baseline for future comparisons and contribute important data for climate modelling and aid the detection of changes that may occur due to climate or environmental change. LINKS TO OTHER INDICATORS SOE Indicator 1 - Monthly mean air temperatures at Australian Antarctic stations SOE Indicator 40 - Average sea surface temperatures in latitude bands 40-50oS, 50-60oS, 60oS-continent SOE Indicator 41 - Average sea surface salinity in latitude bands: 40-50oS, 50-60oS, 60oS-continent SOE Indicator 42 - Antarctic sea ice extent and concentration The fast ice data are also available as a direct download via the url given below. The data are in word documents, and are divided up by year and site (there are three sites (a,b,c) at each station). Snow thickness data have also been included. A pdf document detailing how the observations are collected is also available for download.