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  • The combination of anthropogenic activity and climate variability has resulted in changes to hydrologic regimes across the globe. Changes in water availability impact on vegetation structure and function, particularly in semi-arid landscapes. Riparian and floodplain vegetation communities are sensitive to changes to surface-water and groundwater availability in these water-limited landscapes. Remote-sensing multi-temporal methods can be used to detect changes in vegetation at a regional to local scale. In this study, a `best-available pixel' approach was used to represent dry-season, woody-vegetation-canopy characteristics inferred from Normalised Difference Vegetation Index (NDVI). This paper describes a method in which Landsat 5 TM and Landsat 7 ETM+ data from 1987 to 2011 were processed using object-based image-analysis techniques to generate annual minimum NDVI values for vegetation communities in the Lower-Darling floodplain The changes detected in riparian and floodplain canopies over time can then be integrated with other spatial data to identify water-source dependence and infer a relationship between changes to the hydrologic characteristics of specific water sources and vegetation dynamics.

  • Completion of a pilot study over the Namoi and Murrumbidgee catchments was part of the 2012-13 project schedule between Bureau of Meteorology (Bureau) and Geoscience Australia. The purpose of the pilot was to consolidate four years of research and development of the 1 second SRTM DEM, ANUDEM Streams, and National Catchment Boundaries to enable GA operational capacity to recreate the foundation datasets for Geofabric Phase 3 deliverables. This report is aimed to highlight how successfully the process has worked, issues that have arisen and identify and develop future modifications of the methodology to enable the production of Phase 3 Geofabric products. This professional opinion has been created for the Bureau and the Geofabric Steering Committees for review of Phase 3 of the Geofabric.

  • Fresh groundwater resources are a highly valuable commodity, particularly in semi-arid to arid landscapes where annual precipitation is low and surface water is scarce. Water security, often achieved through the development of groundwater resources, is a high priority for rural communities within these water-limited landscapes. However this is often at the expense of the environment when alterations to the groundwater system, often in conjunction with drought conditions, can detrimentally impact floodplain and riparian vegetation structure and function. Remote-sensing methods can be used to detect such changes in vegetation. In this study, a multi-temporal Landsat Normalised Difference Vegetation Index (NDVI) approach was used to detect changes in riparian and floodplain vegetation in the Lower-Darling floodplain, NSW, Australia. When integrated with surface and subsurface data, these changes provided insight into how surface water availability and subsurface geological and hydrogeological characteristics influenced vegetation distribution and behaviour at multiple scales. It was found that while the availability of water resources was the primary driver of changes in vegetation canopy dynamics, this availability was strongly influenced by both tectonic and hydrogeological processes. These findings were of particular importance when considering the suitability of groundwater development options and they have implications for future groundwater assessment studies.

  • Geoscience Australia's entry to the ASC2014 SPECTRUM science-art exhibition Title: Seeing Water Through Time Author: Norman Mueller Type: Science Communication image Description: The WOfS, Water Observations from Space, image is a colour-scale of how many times water was detected from the Landsat 5 and 7 satellites over central Australia from 1998 to 2012. The colours range from very low number of times (red) to very high number of times (blue), using a standard rainbow colour scheme (red-orange-yellow-green-blue). This means that red areas are hardly ever wet while blue areas are more permanent water features like lakes. The area covered includes Lake Eyre (at left) Cooper Creek (right of centre) to the Paroo River (bottom right).

  • Summary XML files complying with the Australian Flood Study Data Model including one file for each Jurisdiction and on All-in-one file.

  • The Surface Hydrology Points (National) dataset presents the spatial locations of surface hydrology point features and its attributes. The dataset represents the Australia's surface hydrology at a national scale. It includes natural and man-made geographic features such as: lake, soak, pool, spring, waterfall, bore, etc. This product presents small hydrology features over the entire continental of Australia.

  • The Surface Hydrology Points (Regional) dataset provides a set of related features classes to be used as the basis of the production of consistent hydrological information. This dataset contains a geometric representation of major hydrographic point elements - both natural and artificial. This dataset is the best available data supplied by Jurisdictions and aggregated by Geoscience Australia it is intended for defining hydrological features.

  • The Surface Hydrology Lines (National) dataset presents the spatial locations of surface hydrology line features and its attributes. The dataset represents the Australia's surface hydrology at a national scale. It includes natural and man-made geographic features such as: watercourses, canals, pipelines, etc. This product presents line hydrology features with full topological connectivity and flow paths for the entire continental of Australia.

  • Subtitle: Behind the Scenes of Geofabric Version 3 Pilot & the Future of Geospatial Surface Water Information The Bureau of Meteorology's Australian Hydrological Geospatial Fabric (Geofabric) was established in 2008 as the spatial information database to support water accounting and resource assessment mandated under the Water Act 2007. Foundation layers for Geofabric versions 1 and 2 were developed from 1:250K streamline data and the 9 second resolution national DEM. The uses of the Geofabric data have expanded to new disciplines and have resulted in increased demand for finer national resolution. Version 3 of the Geofabric is now under development in a collaborative project between Geoscience Australia, CSIRO, Australian National University (ANU) and the Bureau of Meteorology. The foundation inputs for Geofabric version 3 are based on the integrated national surface hydrology dataset which uses the best available scale data from the jurisdictions and the 1 second resolution SRTM DEM. This significant enhancement presents both challenges and opportunities. This presentation at the Surveying & Spatial Sciences Institute (SSSI) ACT Region conference on 16 August 2013 aims to show the work being undertaken in the pilot areas of the Namoi and Murrumbidgee River Regions.

  • <b>This record was retired 01/04/2022 with approval from M.Wilson as it has been superseded by eCat 146091 Geoscience Australia Landsat Water Observation Statistics Collection 3</b> WOfS is a gridded dataset indicating areas where surface water has been observed using the Geoscience Australia (GA) Earth observation satellite data holdings. The WOfS product version 1.5 includes observations taken between 1987 to November 2014 from the Landsat 5 and 7 satellites. WOfS version 1.5 includes observations from 1987 to March 2014. Future versions of the product will extend the temporal range and diversify the data sources. WOfS covers all of mainland Australia and Tasmania but excludes off-shore Territories.