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  • Abstract: Land Surface Temperature (Ts) is an important boundary condition in many land surface modelling schemes. It is also important in other application areas such as, hydrology, urban environmental monitoring, agriculture, ecological and bushfire monitoring. Many studies have shown that it is possible to retrieve Ts on a global scale using thermal infrared data from satellites. Development of standard methodologies that generate Ts products routinely would be of broad benefit to the application of remote sensing data in areas such as hydrology and urban monitoring. AVHRR and MODIS datasets are routinely used to deliver Ts products. However, these data have 1km spatial resolution, which is too coarse to detect the detailed variation of land surface change of concern in many applications, especially in heterogeneous areas. Higher resolution thermal data from Landsat is a possible option in such cases. To derive Ts, two scientific problems need to be resolved: to remove the atmospheric effects and derive surface brightness temperature (TB) and to separate the emissivity and Ts effects in the surface brightness temperature (TB). To derive TB, for single thermal band sensors such as, Landsat 5, 7 and (due to a faulty dual-band thermal instrument) on Landsat-8, the split window methods, such as those used for NOAAAVHRR data (Becker & Li, 1990), and the day/night pairs of thermal infrared data in several bands, as used for MODIS (Wan et al., 2002) are not available for correcting atmospheric effects. The retrieval of surface brightness temperature TB from Landsat data therefore needs more care, as the accuracy of the TB retrieval depends critically on the ancillary data, such as atmospheric water vapour data (precipitable water). In this paper, a feasible operational method to remove the atmospheric effects and retrieve surface brightness temperature from Landsat data is presented. The method uses the MODTRAN 5 radiative transfer model and global atmospheric profile data sets, such as NASA MERRA (The Modern Era Retrospective-Analysis for Research and Applications) atmospheric profiles, NOAA NCEP (National Center for Environmental Prediction) reanalysis product and ECMWF (The European Centre for Medium-Range Weather Forecasts) to correct for the atmospheric effects. The results derived from the global atmospheric profiles are assessed against the TB product estimated by using (accurate) ground based radiosonde data (balloon data). The results from this study have found: The global data sets NCEP1, NCEP2, MERRA and ECMWF can all generally give satisfactory TB products and can meet the levels of accuracy demanded by many practitioners, such as 1º K. Among global data sets, ECMWF data set performs best. The root mean square difference (RMSD) for the 9 days and 3 test sites are all within 0.4º K when compared with the TB products estimated using ground radiosonde measurements.

  • Imagine you are an incident controller viewing a computer screen which depicts the likely spread of a bushfire that's just started. The display shows houses and other structures in the fire's path, and even the demographics of the people living in the area, such as the number of people, their age spread, whether households have independent transport, and whether English is their second language. In addition, imagine that you can quantify and display the uncertainty in both the fire weather and also the type and state of the vegetation, visualising the sensitivity of the expected fire spread and impact to these uncertainties. It will be possible to consider 'what if' scenarios as the event unfolds, and reject those scenarios that are no longer plausible. The advantages of such a simulation system in making speedy, well-informed decisions has been considered by a group of Bushfire CRC researchers who have collaborated to produce a 'proof of concept' for such a system, demonstrated initially on three case studies. The 'proof of concept' system has the working name FireDST (Fire Impact and Risk Evaluation Decision Support Tool). FireDST links various databases and models, including the Phoenix RapidFire fire prediction model and building vulnerability assessment models, as well as infrastructure and demographic databases. The information is assembled into an integrated simulation framework through a geographical information system (GIS) interface. Pre-processed information, such as factors that determine the local and regional wind, and also the typical response of buildings to fire, are linked through a database, along with census-derived social and economic information. This presentation provides an overview of the FireDST simulation 'proof of concept' tool and walks through a sample probabilistic simulation constructed using the tool. Handbook MODSIM2013 Conference

  • An integrated analysis of geoscience information and benthos data has been used to identify benthic biotopes (seafloor habitats and associated communities) in the nearshore marine environment of the Vestfold Hills, East Antarctica. High-resolution bathymetry and backscatter data were collected over 42km2 to depths of 215 m using a multibeam sonar system. Epibenthic community data and in situ observations of seafloor morphology, substrate composition and bedforms were obtained from towed underwater video. Analysis of the datasets was used to identify statistically distinct benthic assemblages and describe the physical habitat characteristics related to each assemblage, with seven discrete biotopes identified. The biotopes include a range of habitat types including shallow coastal embayments and rocky outcrops which are dominated by dense macroalgae communities, and deep muddy basins which are dominated by mixed invertebrate communities. Transition zones comprising steep slopes provide habitat for sessile invertebrate communities. Areas of flat sandy plains are relatively barren. The relationship between benthic community composition and environmental parameters is complex with many variables (e.g. depth, substrate type, longitude, latitude and slope) contributing to differences in community composition. Depth and substrate type were identified as the main drivers of benthic community composition, however, depth is likely a proxy for other unmeasured depth-dependent parameters such as light availability, frequency of disturbance by ice, currents and/or food availability. Sea ice cover is also an important driver and the benthic community in areas of extended sea ice cover is comprised of sessile invertebrates and devoid of macroalgae. This is the first study that has used an integrated sampling approach based on multibeam sonar and towed underwater video to investigate benthic assemblages across a range of habitats in a nearshore marine environment in East Antarctica. This study demonstrates the efficacy of using multibeam sonar and towed video systems to survey large areas of the seafloor and to collect non-destructive high-resolution data in the sensitive Antarctic marine environment. The multibeam data provide a physical framework for understanding benthic habitats and the distribution of benthic communities. This research provides a baseline for assessing natural variability and human induced change on nearshore marine benthic communities (Australian Antarctic Science Project AAS-2201), contributes to Geoscience Australia's Marine Environmental Baseline Program, and supports Australian Government objectives to manage and protect the Antarctic marine environment.

  • As part of the controlled release experiments at the Ginninderra test site, geophysical surveys have been acquired using electromagnetic techniques at a range of frequencies. The primary objective was to assess whether these could provide insight into the soil structure at the site, give guidance as to where to monitor for leakage, and provide additional information that may explain the observed sub-surface and surface CO2 migration behavior. A secondary objective was to assess whether CO2 leaks could be located based on secondary impacts such as drying of the soil profile. Ground penetrating radar surveys were taken during the second release experiment (October - December 2012). Different frequency shielded antennas were trialled in order to optimize the signal. Two surveys were conducted: one baseline survey prior to CO2 release and another during the release experiment. The GPR results show a reduction in range and clear reflections to the west indicating that clay was present. To the east we see clearer reflections from sand layers and the water table. These observations corresponded with larger scale sub-surface soil features determined from EM31 and EM38 electromagnetic surveys. Application of these geophysical surveys for CO2 leak detection and monitoring design are discussed. Paper for CO2CRC Research Symposium 2013

  • Geoscience Australia defines a sample as a feature observed, measured or collected in the field. A specimen is a physical individual sample collected during the field work. This data set represents a subset of all Sampling data held by Geoscience Australia that have been collected as part of drilling activities (ie relate to Australian Boreholes). The data will be utilised by other data domains by providing Sampling context to various Observation & Measurement data.

  • As a participating organisation in the Global Mapping Project, and following discussions held at the 22nd meeting of the International Steering Committee for Global Mapping (ISCGM), the Secretariat of the ISCGM has requested the assistance of Geoscience Australia in the validation of intermediate products of global land cover, the Global Land Cover by National Mapping Organisation (GLCNMO) version 3. The request sent to Geoscience Australia involves the use of existing maps and other materials, based on expertise and knowledge to report the validation of the GLCNMO version 3 datasets.

  • Monitoring is a regulatory requirement for all carbon dioxide capture and geological storage (CCS) projects to verify containment of injected carbon dioxide (CO2) within a licensed geological storage complex. Carbon markets require CO2 storage to be verified. The public wants assurances CCS projects will not cause any harm to themselves, the environment or other natural resources. In the unlikely event that CO2 leaks from a storage complex, and into groundwater, to the surface, atmosphere or ocean, then monitoring methods will be required to locate, assess and quantify the leak, and to inform the community about the risks and impacts on health, safety and the environment. This paper considers strategies to improve the efficiency of monitoring the large surface area overlying onshore storage complexes. We provide a synthesis of findings from monitoring for CO2 leakage at geological storage sites both natural and engineered, and from monitoring controlled releases of CO2 at four shallow release facilities - ZERT (USA), Ginninderra (Australia), Ressacada (Brazil) and CO2 field lab (Norway).

  • <b>IMPORTANT NOTICE:</b> This web service has been deprecated. The Hydrochemistry Service OGC service at https://services.ga.gov.au/gis/hydrogeochemistry/ows should now be used for accessing Geoscience Australia hydrochemistry analyses data. This is an Open Geospatial Consortium (OGC) web service providing access to hydrochemistry data (groundwater analyses) obtained from water samples collected from Australian water bores.

  • This web service contains marine geospatial data held by Geoscience Australia. It includes bathymetry and backscatter gridded data plus derived layers, bathymetry coverage information, bathmetry collection priority and planning areas, marine sediment data and other derived products. It also contains the 150 m and optimal resolution bathymetry, 5 m sidescan sonar (SSS) and synthetic aperture sonar (SAS) data collected during phase 1 and 2 marine surveys conducted by the Governments of Australia, Malaysia and the People's Republic of China for the search of Malaysian Airlines Flight MH370 in the Indian Ocean. This web service allows exploration of the seafloor topography through the compilation of multibeam sonar and other marine datasets acquired.

  • This web service contains marine geospatial data held by Geoscience Australia. It includes bathymetry and backscatter gridded data plus derived layers, bathymetry coverage information, bathmetry collection priority and planning areas, marine sediment data and other derived products. It also contains the 150 m and optimal resolution bathymetry, 5 m sidescan sonar (SSS) and synthetic aperture sonar (SAS) data collected during phase 1 and 2 marine surveys conducted by the Governments of Australia, Malaysia and the People's Republic of China for the search of Malaysian Airlines Flight MH370 in the Indian Ocean. This web service allows exploration of the seafloor topography through the compilation of multibeam sonar and other marine datasets acquired.