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  • <div>The A1 poster incorporates 4 images of Australia taken from space by Earth observing satellites. The accompanying text briefly introduces sensors and the bands within the electromagnetic spectrum. The images include examples of both true and false colour and the diverse range of applications of satellite images such as tracking visible changes to the Earth’s surface like crop growth, bushfires, coastal changes and floods. Scientists, land and emergency managers use satellite images to analyse vegetation, surface water or human activities as well as evaluate natural&nbsp;hazards.</div>

  • The OzCoasts web-based database and information system draws together a diverse range of data and information on Australia's coasts and its estuaries. Maps, images, reports and data can be downloaded and there are tools to assist with coastal science, monitoring, management and policy. The content is arranged into seven inter-linked modules: Search Data, Conceptual Models, Coastal Indicators, Habitat Mapping, Natural Resource Management, Landform and Stability Maps and Climate Change. The Climate Change module is the newest feature of the website and was developed in partnership with the Australian Government Department of Climate Change and Energy Efficiency. The module provides information and tools to help communicate the risks of sea-level rise and other potential impacts of climate change on coastal areas. It includes an elevation data and a modelling portal for access to existing and new elevation data and derived products, including sea level inundation maps for Perth to Mandurah, Melbourne, Sydney, Hunter and Central Coast & Brisbane and Gold Coast. The inundation footprints illustrate three sea level rise scenarios: a low (0.5m), medium (0.8m) and high (1.1m) scenario for a 2100 time period, with values based on IPCC projections (B1 and A1FI scenarios) and more recent science. OzCoasts will also soon deliver the Coastal Eutrophication Risk Assessment Tool (CERAT) for the NSW Department of Environment, Climate Change and Water, and the Australian Riverscape Classification Service (AURICL) for the Tropical Rivers and Coastal Knowledge (TRaCK) consortium. CERAT will help identify and prioritise land use planning decisions to protect and preserve the health of NSW estuaries. AURICL has a northern tropical focus, and is a dynamic and flexible system for classifying catchments and their rivers based on the similarity, or dissimilarity, of a wide range of parameters.

  • The variability in the inherent optical properties along an estuary-coast-ocean continuum in tropical Australia has been studied. The study area, the Fitzroy Estuary and Keppel Bay system, is a shallow coastal environment (depth < 30 m) with highly turbid waters in the estuary and blue oceanic waters in the bay and subject to macrotides. Biogeochemical and inherent optical properties (IOPs) were sampled in the near-surface layer spatially and across the tidal phase during the dry season. These determinations included continuous measurements of spectral absorption, scattering and backscattering coefficients, together with discrete measurements of spectral absorption coefficients of phytoplankton, nonalgal particles and colored dissolved organic matter, and concentrations of phytoplankton pigments and suspended matter. Because of a large variability in the characteristics of the water components on short spatial and temporal scales, we observe a large variability in the associated optical properties. From the estuary to the bay, particle scattering and dissolved absorption decreased by 2 orders of magnitude, and nonalgal particle absorption decreased by 3 orders of magnitude. We also observed a strong variability in particle single scattering albedo and backscattering efficiency (by a factor of 6) and in specific IOPs (IOPs normalized by the relevant constituent concentration) such as suspended matter-specific particle scattering and chlorophyll-specific phytoplankton absorption. Superimposed on this strong spatial variability is the effect of the semidiurnal tide, which affects the spatial distribution of all measured properties. These results emphasize the need for spatially and temporally adjusted algorithms for remote sensing in complex coastal systems.

  • Note that this Record has now been published as Record 2014/050, GeoCat number 78802

  • Geoscience Australia conducted a survey of lakebed (benthic) nutrient fluxes in St Georges Basin, November 2003. The objectives were to: 1. determine the nature of nutrient cycling between the sediment and overlying water; and 2. determine the implications of benthic nutrient fluxes for water quality in the estuary. The relevance to management of this work is that it gives an indication of the susceptibility of the estuary to eutrophication from increased nutrient loads from the catchment. The key findings of the study were: - St Georges Basin was mesotrophic to eutrophic at the time of the survey (spring) based on relatively high respiration rates and O2 demand in the sediments measured by in situ benthic chambers. - Respiration rates were linked to phytoplankton biomass (mainly diatoms) where local fluvial discharge of dissolved nutrients created enhanced primary productivity in the water column, which in turn enhanced mineralisation rates. - St Georges Basin had comparatively low denitrification efficiencies (less than 60%). - St Georges Basin is likely to be prone to eutrophication and may have little tolerance for increases in nutrient and organic matter from the catchment due to the low denitrification efficiencies.

  • This study examined the geomorphology of the sea bed, the spatial distribution of the various sediment types and the geomorphic evolution of Cockburn Sound.

  • The Australian Government, through the Department of Climate Change and Energy Efficiency, recognises the need for information that allows communities to decide on a strategy for climate change adaptation. A first pass national assessment of vulnerability to Australia's coast identified that considerable sections of the coast could be impacted by sea level rise. This assessment however, did not provide sufficient detail to allow adaptation planning at a local level. Accounting for sea level rise in planning procedures requires knowledge of the future coastline, which is still lacking. Modelling the coastline given sea level rise is complex, however. Erosion will alter the shores in varied ways around Australia's coastline, and extreme events will inundate areas that currently appear to be well above the projected sea level. Moreover, the current planning practice of designating zones with acceptable inundation risk is no longer practical when considering climate change, as this is likely to remain uncertain for some time. Geoscience Australia, with support from the DCCEE, has now conducted a more detailed study for a local area in Western Australia that was identified to be at high risk in the national assessment. The aim of the project was to develop a localised approach so that information could be developed to support adaptation to climate change in planning decisions at the community level. The approach included modelling a historical tropical cyclone and its associated storm surge for a range of sea level rise scenarios. The approach also included a shoreline translation model that forecast changes in coastal sediment transport. Inundation footprints were created and integrated with Geoscience Australia's national exposure information system, NEXIS, to develop impact assessments on building assets, roads and railways. Studies such as this can be a first step towards enabling the planning process to adapt to increased risk.

  • Geoscience Australia conducted a survey to measure the benthic nutrient fluxes in Wallis Lake, during February 2003. The objectives were to: 1. measure the nutrient (and other metabolite) fluxes across the sediment-water interface at sites in Pipers Creek, Muddy Creek, Wallis Creek and in the Central Basin of Wallis Lake; 2. describe key processes controlling the nutrient fluxes across the sediment-water interface at each of the four sites; and 3. determine the trophic state and assess the estuarine condition of the four selected sites in Wallis Lake. The results of this recent summertime survey were compared to the observations made during the winter survey conducted in June, 2000. Pipers Creek and muddy Creek were similar in that they were both poorly flushed and close to nutrient discharges. These sites are at risk of experiencing eutrophic conditions. Wallis Creek had a high carbon loading, however the presence of seagrass and high denitrification efficiencies means this site remains in a 'good condition. Similarly, the Central Basin remains in a 'good' condition despite an increase in the carbon loading between winter and summer.