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  • 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 purpose of this paper is to investigate and quantify the accuracy with which hydrological signals in the Murray-Darling Basin, southeast Australia can be estimated from GRACE. We assessed the extent to which the Earth's major geophysical processes contaminate the gravitational signals in the Basin. Eighteen of the world's largest geophysical processes which generate major gravitational signals (e.g. melting of the Greenland icesheet, hydrology in the Amazon Basin) were simulated and the proportion of the simulated signal detected in the Murray - Darling Basin was calculated. The sum of the cumulative effects revealed a maximum of ~4 mm (equivalent water height) of spurious signal was detected within the Murray - Darling Basin; a magnitude smaller than the uncertainty of the basin-scale estimates of changes in total water storage. Thus, GRACE products can be used to monitor broad scale hydrologic trends and variability in the Murray-Darling Basin without the need to account for contamination of the estimates from external geophysical sources.

  • In many areas of the world, vegetation dynamics in semi-arid floodplain environments have been seriously impacted by increased river regulation and groundwater use. In this study, the condition of two of Australia's iconic riparian and floodplain vegetation elements, River Red Gums (Eucalyptus camaldulensis) and Black Box (E. largiflorens) are examined in relation to differing hydraulic regimes. With increases in regulation along Murray-Darling Basin rivers, flood volume, seasonality and frequency have changed which has in turn affected the condition and distribution of vegetation. Rather than undertaking a field based assessment of tree health in response to current water regimes, this paper documents a remote sensing study that assessed historic response of vegetation to a range of different climatic and hydraulic regimes at a floodplain scale. This methodology innovatively combined high-resolution vegetation structural mapping derived from LiDAR data (Canopy Digital Elevation Model and Foliage Projected Cover) with 23 years of Landsat time-series data. Statistical summaries of Normalised Difference Vegetation Index values were generated for each spatially continuous vegetation structural class (e.g. stand of closed forest) for each Landsat scene. Consequently long-term temporal change in vegetation condition was assessed against different water regimes (drought, local rainfall, river bank full, overbank flow, and lake filling). Results provide insight into vegetation response to different water sources and overall water availability. Additionally, some inferences can be made about lag times associated with vegetation response and the duration of the response once water availability has declined (e.g. after floodwaters recede). This methodology should enable water managers to better assess the adequacy of environmental flows.

  • The purpose of this paper is to investigate and quantify the accuracy with which hydrological signals in the Murray-Darling Basin, southeast Australia can be estimated from GRACE. We assessed the extent to which the Earth's major geophysical processes contaminate the gravitational signals in the Basin. Eighteen of the world's largest geophysical processes which generate major gravitational signals (e.g. melting of the Greenland icesheet, hydrology in the Amazon Basin) were simulated and the proportion of the simulated signal detected in the Murray - Darling Basin was calculated. The sum of the cumulative effects revealed a maximum of ~4 mm (equivalent water height) of spurious signal was detected within the Murray - Darling Basin; a magnitude smaller than the uncertainty of the basin-scale estimates of changes in total water storage. Thus, GRACE products can be used to monitor broad scale hydrologic trends and variability in the Murray-Darling Basin without the need to account for contamination of the estimates from external geophysical sources.

  • The 1 second Shuttle Radar Topographic Mission (SRTM) derived smoothed Digital Elevation Model (DEM-S) Version 1.0 is a 1 arc second (~30m) gridded smoothed version of the DEM (ANZCW0703013355). The DEM-S represents ground surface topography, excluding vegetation features, and has been smoothed to reduce noise and improve the representation of surface shape. The dataset was derived from the 1 second Digital Elevation Model Version 1.0 (DSM; ANZCW0703013336) by an adaptive smoothing process that applies more smoothing in flatter areas than hilly areas, and more smoothing in noisier areas than in less noisy areas. This DEM-S supports calculation of local terrain shape attributes such as slope, aspect and curvatures that could not be reliably derived from the unsmoothed DEM because of noise. A full description of the methods is in progress (Gallant et al., in prep) and in the User Guide (Geoscience Australia & CSIRO, 2010).

  • The 1 second SRTM derived DEM-H Version 1.0 is a 1 arc second (~30 m) gridded digital elevation model (DEM) that has been hydrologically conditioned and drainage enforced. The DEM-H captures flow paths based on SRTM elevations and mapped stream lines, and supports delineation of catchments and related hydrological attributes. The dataset was derived from the 1 second smoothed Digital Elevation Model (DEM-S; ANZCW0703014016) by enforcing hydrological connectivity with the ANUDEM software, using selected AusHydro V1.6 (February 2010) 1:250,000 scale watercourse lines (ANZCW0503900101) and lines derived from DEM-S to define the watercourses. The drainage enforcement has produced a consistent representation of hydrological connectivity with some elevation artefacts resulting from the drainage enforcement. A full description of the methods is in preparation (Dowling et al., in prep). This product is the last of the Version 1.0 series derived from the 1 second SRTM (DSM, DEM, DEM-S and DEM-H) and provides a DEM suitable for use in hydrological analysis such as catchment definition and flow routing.

  • Contains a medium scale vector representation of the topography of Australia. The data include the following themes: Hydrography - drainage networks including watercourses, lakes, wetlands, bores and offshore features; Infrastructure - constructed features to support road, rail and air transportation as well as built-up areas, localities and homesteads. Utilities, pipelines, fences and powerlines are also included; Relief - features depicting the terrain of the earth including 50 metre contours, spot heights, sand dunes, craters and cliffs; Vegetation - depicting forested areas, orchards, mangroves, pine plantations and rainforests; and Reserved Areas - areas reserved for special purposes including nature conservation reserves, aboriginal reserves, prohibited areas and water supply reserves.

  • <p>The GEODATA 9 Second Digital Elevation Model (DEM-9S) Version 3 is a grid of ground level elevation points covering the whole of Australia with a grid spacing of 9 seconds in longitude and latitude (approximately 250 metres) in the GDA94 coordinate system. <p>Version 3 of the DEM-9S was calculated by Version 5.2.2 of the ANUDEM procedure (Hutchinson 2007) from comprehensively revised and augmented national GEODATA-250K topographic source data (AUSLIG 1992, Geoscience Australia 2003, Geoscience Australia 2006) using Version 5.2.2 of the ANUDEM elevation gridding procedure. The source data included revised versions of GEODATA-250K elevation points, streamlines, cliff lines and waterbodies, trigonometric points from the National Geodetic Database and additional elevation and sink point data digitised by the Fenner School from 1:100K source material. Version 5.2.2 of the ANUDEM procedure incorporates major upgrades to the modelling of streamlines, lakes, cliff lines and the coastline. <p>GEODATA 9 Second Flow Direction Grid (D8-9S) has been released for the first time with Version 3. The D8-9S is a corresponding grid describing the principal directions of surface drainage across the whole of Australia. This grid was calculated by the ANUDEM procedure as it derived the DEM-9S. It incorporates the data streamline structure and describes the drainage structure continent-wide. It can be used to delineate streamlines and associated catchment boundaries for the DEM-9S. This is particularly useful in low relief areas where drainage structure is not reliably defined by the DEM-9S elevations alone. <p>The product can be used for applications requiring accurate representation of absolute elevation values. The elevation of source data high points (hills or mountains) is well represented in Version 3. The 1:250,000 source scale of the elevation grid makes the product useful for national, State-wide and regional applications. <p>For more detailed information please refer to the User Guide below. <p>Product Information <p>Coverage: Australia, excluding external territories <p>Currency: 2008 <p>Coordinates: Geographical <p>Datum: Horizontal: GDA94; Vertical: AHD71 <p>Available Formats: GeoTIFF

  • 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.

  • 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.