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Metadata record for data from ASAC Project 545 See the link below for public details on this project. From the abstract of the referenced paper: Blood was collected for haematological, red cell enzyme and red cell metabolic intermediate studies from 20 Southern elephant seals Mirounga leonina. Mean haematological values were: haemoglobin (Hb) 22.4 plus or minus 1.4 g/dl, packed cell volume (PCV) 54.2 plus or minus 3.8%, mean cell volume (MCV) 213 plus or minus 5 fl and red cell count (RCC) 2.5 x 10 to power 12 / l. Red cell morphology was unremarkable. Most of the red cell enzymes showed low activity in comparison with human red cells. Haemoglobin electrophoresis showed a typical pinniped pattern, ie two major components. Total leucocyte counts, platelet counts, and coagulation studies were within expected mammalian limits. Eosinophil counts varied from 0.5 x 10 to power 9 / l (5%-49%), and there was a very wide variation in erythrocyte sedimentation rates, from 3 to 60mm/h.
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Metadata record for data from ASAC Project 1119 See the link below for public details on this project. A marked bend in the Hawaiian-Emperor seamount chain supposedly resulted from a recent major reorganization of the plate-mantle system there 50 million years ago. Although alternative mantle-driven and plate-shifting hypotheses have been proposed, no contemporaneous circum-Pacific plate events have been identified. We report reconstructions for Australia and Antarctica that reveal a major plate reorganization between 50 and 53 million years ago. Revised Pacific Ocean sea-floor reconstructions suggest that subduction of the Pacific-Izanagi spreading ridge and subsequent Marianas/Tonga-Kermadec subduction initiation may have been the ultimate causes of these events. Thus, these plate reconstructions solve long-standing continental fit problems and improve constraints on the motion between East and West Antarctica and global plate circuit closure.
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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
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A geomorphology map of the Australasian seafloor was created as a Geographic Information System layer for the study described in Torres, Leigh G., et al. "From exploitation to conservation: habitat models using whaling data predict distribution patterns and threat exposure of an endangered whale." Diversity and Distributions 19.9 (2013): 1138-1152. The geomorphology map was generated using parameters derived from the General Bathymetric Chart of the World (GEBCO 2008, http://www.gebco.net/), with 30 arc-second grid resolution. Geomorphology features were delineated manually with a consistent spatial resolution. Each feature was assigned a primary attribute of depth zone and a secondary attribute of morphological feature. The following feature classes are defined: shelf, slope, rise, plain, valley, trench, trough, basin, hills(s), mountains(s), ridges(s), plateau, seamount. Further information (methods, definitions and an illustration of the geomorphology map) is provided in Appendix S2 of the paper which is available for download (see related URLs).
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Bathymetric Contours and height range polygons of approaches to Davis Station, derived from RAN Fair sheet, Aurora Australis and GEBCO soundings.
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This metadata record was created in error and a DOI assigned to it before the error was noticed. The correct metadata record is available here: https://data.aad.gov.au/metadata/records/AAS_4015_Krill_Gonad_Transcriptome with the DOI doi:10.26179/5cd3c8fec9ad8.
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In this project a simplified computer model was developed to reflect the variation and influences of sea ice on the atmosphere. The model was incorporated into a global general circulation model. The data set resulting from the project consists of simulated sea ice characteristics (concentration etc.) available on a regular global grid. From the abstracts of some of the referenced papers: An observed ocean-drift data set is used as the basis of a wind-driven coupled ocean-sea-ice-atmosphere model including interaction and feedback. The observed characteristics of the Antarctic sea ice are described including the ice thickness, ice concentration and horizontal advection. The atmospheric model computes heat fluxes, sea-ice growth, changes in concentration and advection. Sensitivity studies show reasonable and stable simulations of the observed sea-ice characteristics for the present mean Antarctic winter climate. The response times and feedbacks of the ice-atmosphere system as represented by the model appear to allow scope for the development of some persistence of anomalies. To assess the sensitivity of the southern hemisphere circulation to changes in the fraction of open water in the sea ice we have conducted four experiments with a July 21-wave General Circulation Model (GCM) with this fraction set to 5, 50, 80 and 100%. The mean surface temperatures and the surface atmospheric temperatures over the sea ice increased as the water fraction increased and the largest changes were simulated adjacent to the coast. Significant anomalies in the surface heat fluxes, particularly those of sensible heat, accompanied the decrease in the sea ice concentration. Substantial atmospheric warming was simulated over and in the vicinity of areas in which leads were considered. In all but one experiment there were anomalous easterlies between about 40 and 60S with westerly anomalies further to the south. The surface pressure at high latitudes appears to change in a consistent fashion with the fraction of open water, with the largest changes occurring in the Weddell and near the Ross Seas. Some of the feedbacks which may enhance the responses here, but which are not included in our model are discussed. We present a simple parameterisation of the effect of open leads in a general circulation model of the atmosphere. We consider only the case where the sea ice distribution is prescribed (ie not alternative) and the fraction of open water in the ice is also prescribed and set at the same value at all points in the Southern Hemisphere and a different value in the Northern Hemisphere. We approximate the distribution of sea ice over a model 'grid box' as a part of the box being covered by solid ice of uniform thickness and the complement of the box consisting of open water at a fixed -1.8 degrees C. Because of the nonlinearity in the flux computations, separate calculations are performed over the solid sea ice and over the open leads. The net fluxes conveyed to the atmosphere over the grid box are determined by performing the appropriate area-weighted average over the two surface types. We report on an experiment designed to assess the sensitivity of the modelled climate to the imposition of a 50% concentration in the winter Antarctic sea ice. Significant warming of up to 6 degrees C takes place in the vicinity of and above the Antarctic sea ice and is associated with significant changes in the zonal wind structure. Pressure reductions are simulated over the sea ice, being particularly marked in the Weddell Sea region, and an anomalous east-west aligned ridge is simulated at about 60S. Very large changes in the sensible heat flux (in excess of 200 W per square metre) are simulated near the coast of Antarctica. Increasingly, many aspects of the study of Antarctica and the high southern latitudes are being aided by various types of numerical models. Among these are the General Circulation Models (GCMs), which are powerful tools that can be used to understand the maintenance of present atmospheric climate and determine its sensitivity to proposed changes. The changes in the ability of GCMSs used over the last two decades to simulate aspects of atmospheric climate at high southern latitudes are traced and it is concluded there has been a steady improvement in model products. The task of assessing model climates in high southern latitudes is made difficult by the uncertainties in the data used for the climatological statistics. It is suggested that the quality of the climates produced by most modern GCMs in many aspects cannot be said to be poor, especially considering the uncertainties in 'observed' climate. There is obviously need for improvements in both modelling and observations. Finally, some topics are highlighted in which the formulation of models could be improved, with special reference to better treatment of physical processes at high southern latitudes.
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From December 2014 to February 2015, Geoscience Australia conducted a multibeam sonar survey (GA-0348) of the coastal waters around Casey station and the adjacent Windmill Islands. The survey utilised GA's Kongsberg EM3002D multibeam echosounder, motion reference unit and C-Nav differential GPS system mounted on the Australian Antarctic Division's (AAD) science workboat the Howard Burton. The survey was a collaborative project between GA, the AAD and the Royal Australian Navy (RAN). During the survey a total of approximately 27.3 square kilometres of multibeam bathymetry, backscatter and water-column data were collected, extending coverage of a RAN multibeam survey (survey number HI545) conducted the previous season (approximately 7 square kilometres). The regions covered extended seaward of Newcomb Bay and Clark Peninsula northwest of Casey Station, and seaward of Shirley and Beall Islands to the southwest. Complimentary datasets were also collected, including 18 drop video deployments to assess the benthic ecosystem composition and 39 sediment samples to ground-truth the seafloor substrate. Macroalgae spectral analyses were also collected to develop a spectral library for possible future satellite bathymetry investigations. The new high-resolution bathymetric grid (1 metre resolution) reveals seafloor features in the Casey area in unprecedented detail.
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This dataset covers the area of the Australian Exclusive Economic Zone (EEZ) around Heard Island and McDonald Islands (HIMI). The Fisheries sector areas were originally created by Dick Williams, former Fisheries biologist at the Australian Antarctic Division for the HIMI fishery, to define areas of research fishing for the first longline vessels to fish at HIMI in 2003 and 2004. This dataset consists of a polygon shapefile representing the sector areas and a map displaying the sector areas. Each polygon has the attributes polygon number and area in square kilometres. The dataset was created in December 2015 using current boundaries as listed in the Quality section of this record.
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In January 2005 a multi-parametric international experiment was conducted that encompassed both Deception Island and its surrounding waters. This experiment used as main platforms the Spanish Oceanographic vessel 'Hesperides', the Spanish Scientific Antarctic base 'Gabriel de Castilla' at Deception Island and four temporary camps deployed on the volcanic island. This experiment allowed us to record active seismic signals on a large network of seismic stations that were deployed both on land and on the seafloor. In addition other geophysical data were acquired, such as: bathymetric high precision multi-beam data, and gravimetric and magnetic profiles. The gravimeter BELL AEROSPACE-TEXTRON BGM-3 (at the present Lockheed Martin Federal Systems) is an acquisition system that can be used both in aerial and marine vehicles. The system has a sensor mounted in a gyro-stabilized platform. This system is composed of a gravimeter sensor, the stabilized platform and an acquisition system. Raw data are recorded and processed in a computer HP-486/50 using the own BGM software providing two types of data, raw and previously analyzed data. Acquired raw data are presented in the following format: $PRAWGRV, Day, Hour, Flag, Mean Value,. However, the analyzed data are transformed into: $PHESGRV, Day, Hour, Flag, Mean Value, Value GRS67, Eotvos Correction, sinv, sinv. Potential 'flag' values associated to the sensor status are: 0: normal, 2: error, 5: starting.