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.

This service has been created specifically for display in the National Map and the symbology displayed may not suit other mapping applications. Information included within the service includes the point locations for surface hydrology, including natural and man-made features such as water courses (including directional flow paths), lakes, dams and other water bodies and marine themes. The data is sourced from Geoscience Australia 250K Topographic data and Surface Hydrology data. The service contains layer scale dependencies.

Digital elevation models (DEMs) reflect the morphology of landscape surfaces and attributes derived from these models, including slope, aspect, relief and topographic wetness index. DEMs have broad application in geomorphology, geology, hydrology, ecology and climatology. Here, we consider two important terrain attributes: topographic position index and topographic ruggedness. Topographic position index measures the topographic slope position of landforms. It compares the mean elevation of a specific neighbourhood area with the elevation value of a central cell. This is done for every cell or pixel in the DEM to derive the relative topographic position (e.g. upper, middle, lower landscape elements). Ruggedness refers to the roughness of the surface and is calculated as the standard deviation of elevations. Both these terrain attributes are scale dependent and will vary according to the size of the analysis window. Here, we generated a multiscale topographic position model over the Australian continent using a 3-second resolution (~90 m) DEM derived from the Shuttle Radar Topography Mission. The algorithm calculates topographic position scaled by the corresponding ruggedness across three spatial scales (window sizes): 0.2–8.1 km, 8.2–65.2 km and 65.6–147.6 km. The derived ternary image captures variations in topographic position across these spatial scales, giving a rich representation of nested landform features, with broad application to understanding geomorphological and hydrological processes, and mapping regolith and soils. <b>Citation:</b> Wilford, J., Basak, S. and Lindsay, J., 2020. Multiscale topographic position image of the Australian continent. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

CEOS Analysis Ready Data for Land (CARD4L) are satellite data that have been processed to a minimum set of requirements and organized into a form that allows immediate analysis with a minimum of additional user effort and interoperability both through time and with other datasets [1]. In this paper, key input data (e.g. aerosol optical depth, precipitable water, BRDF parameters) needed for atmospheric and BRDF corrections of Landsat data are identified and a sensitivity analysis is conducted using outputs of a physics based atmospheric and BRDF model. The results show that aerosol impacts more on the visible bands where the average variation of reflectance could reach 0.05 of reflectance unit. The variation over dark targets can be much higher so that it is a critical parameter for aquatic applications. By contrast, precipitable water (water vapor in the rest of the paper) only impacts the near-infrared (NIR) and shortwave (SWIR) bands and the extent of change is much smaller. BRDF parameters impact time series most on winter and summer images of highly anisotropic areas and when they are normalized to 45º solar angle. Different BRDF levels for different spectrum ranges not only impact the magnitude of reflectance, but also the signature for these areas. It seems that it is necessary to normalize surface BRDF to ensure time series consistency of the Landsat ARD product. Abstract presented at 2019 IEEE International Geoscience and Remote Sensing Symposium (IGARSS)

This service provides access to hydrochemistry data (groundwater and surface water analyses) obtained from water samples collected from Australian water bores or field sites.

This service has been created specifically for display in the National Map and the symbology displayed may not suit other mapping applications. Information included within the service includes the polygon/area locations for surface hydrology, including natural and man-made features such as water courses (including directional flow paths), lakes, dams and other water bodies and marine themes. The data is sourced from Geoscience Australia 250K Topographic data and Surface Hydrology data. The service contains layer scale dependencies.

Background It is important to know where water is normally present in a landscape, where water is rarely observed, and where inundation has occasionally occurred. These observations tell us where flooding has occurred in the past, and allows us to understand wetlands, water connectivity and surface-groundwater relationships. This can lead to more effective emergency management and risk assessment. This is the principal Digital Earth Australia (DEA) Water product (previously known as Water Observations from Space (WOfS)), providing the individual water observations per satellite image that are subsequently used in the following DEA Watersuite and related water bodies products: DEA Waterbodies (Landsat), DEA Water Observations Statistics (Landsat), DEA Water Observations Filtered Statistics (Landsat). This product shows where surface water was observed by the Landsat satellites on any particular day since mid 1986. These daily data layers are termed Water Observations (WOs). What this product offers DEA Water Observations provides surface water observations derived from Landsat satellite imagery for all of Australia from 1986 to present. The Water Observationsshow the extent of water in a corresponding Landsat scene, along with the degree to which the scene was obscured by clouds, shadows or where sensor problems cause parts of a scene to not be observable.

<p>The outcrop extent of the Nulla Basalt Province, selected from the Queensland Detailed Surface Geology vector polygon mapping, March 2017. <p>© State of Queensland (Department of Natural Resources and Mines) 2017 Creative Commons Attribution

We present a multifaceted hydrogeological investigation of the McBride and Nulla basalt provinces in the Upper Burdekin region, north Queensland. The project aims to better understand their key groundwater system processes to inform future development and water management decisions. This work, carried out as part of the Exploring for the Future Upper Burdekin Groundwater Project, has shown that basalt aquifers in each province are typically unconfined where monitored. Groundwater recharge is widespread but highly variable, largely occurring within the boundaries of the basalt provinces. Groundwater salinity based on electrical conductivity is <1000 μS/cm in the McBride Basalt Province (MBP) and up to 2000 μS/cm in the Nulla Basalt Province (NBP). Groundwater levels have been declining since 2011 (following major flooding in Queensland), showing that the study period covers a small fraction of a longer-functioning dynamic groundwater system. The basalt provinces contain distinct lava flows, and the degree of hydraulic connectivity between them is unclear. Despite similarities in their rock properties, the geometry of lava emplacement leads to different groundwater flow regimes within the two basalt provinces. Radial flow away from the central high elevations towards the edges is characteristic of the MBP, while regional flow from west to east dominates the NBP. Basalt aquifers in both provinces support a range of groundwater-dependent ecosystems, such as springs, some of which sustain flow in tributaries of the Burdekin River. Where streams intersect basalt aquifers, this also results in direct groundwater discharge. Springs and perennial tributaries, particularly emanating from the MBP, provide important inflows to the Burdekin River, especially in the dry season. This work has highlighted that management of MBP and NBP groundwater sources is crucial for maintaining a range of environmental assets in the region and for ensuring access for existing and future users. <b>Citation:</b> Ransley, T.R., Dixon-Jain, P., Cook, S.B., Lai, E.C.S., Kilgour, P., Wallace, L., Dunn, B., Hansen, J.W.L. and Herbert, G., 2020. Hydrogeology of the McBride and Nulla basalt provinces in the Upper Burdekin region, north Queensland. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

The WOfS summary statistic represents, for each pixel, the percentage of time that water is detected at the surface relative to the total number of clear observations. Due to the 25-m by 25-m pixel size of Landsat data, only features greater than 25m by 25m are detected and only features covering multiple pixels are consistently detected. The WOfS summary statistic was produced over the McBride and Nulla Basalt provinces for the entire period of available data (1987 to 2018). Pixels were polygonised and classified in order to visually enhance key data in the imagery. Areas depicted in the dataset have been exaggerated to enable visibility.