Digital Earth
Type of resources
Keywords
Publication year
Service types
Topics
-
Analysis Ready Data (ARD) takes medium resolution satellite imagery captured over the Australian continent and corrects for inconsistencies across land and coastal fringes. The result is accurate and standardised surface reflectance data, which is instrumental in identifying and quantifying environmental change. This product is a single, cohesive ARD package, which allows you to analyse surface reflectance data as is, without the need to apply additional corrections. ARD consists of sub products, including : 1) NBAR Surface Reflectance which produces standardised optical surface reflectance data using robust physical models which correct for variations and inconsistencies in image radiance values. Corrections are performed using Nadir corrected Bi-directional reflectance distribution function Adjusted Reflectance (NBAR). 2) NBART Surface Reflectance which performs the same function as NBAR Surface Reflectance, but also applies terrain illumination correction. 3) OA Observation Attributes product which provides accurate and reliable contextual information about the data. This 'data provenance' provides a chain of information which allows the data to be replicated or utilised by derivative applications. It takes a number of different forms, including satellite, solar and surface geometry and classification attribution labels. ARD enables generation of Derivative Data and information products that represent biophysical parameters, either summarised as statistics, or as observations, which underpin an understanding of environmental dynamics. The development of derivative products to monitor land, inland waterways and coastal features, such as: - urban growth - coastal habitats - mining activities - agricultural activity (e.g. pastoral, irrigated cropping, rain-fed cropping) - water extent Derivative products include: - Water Observations from Space (WOfS) - National Intertidal Digital Elevation Model (NIDEM) - Fractional Cover (FC) - Geomedian ARD and Derivative products are reproduced through a period collection upgrade process for each sensor platform. This process applied improvements to the algorithms and techniques and benefits from improvements applied to the baseline data that feeds into the ARD production processes. <b>Value: </b>These data are used to understand distributions of and changes in surface character, environmental systems, land use. <b>Scope: </b>Australian mainland and some part of adjacent nations. Access data via the DEA web page - <a href="https://www.dea.ga.gov.au/products/baseline-data">https://www.dea.ga.gov.au/products/baseline-data</a>
-
Title: Earth observations for water resources management - Crawford Fund Derek Tribe Address Overview: During the Derek Tribe Address, Dr Lisa-Maria Rebelo will discuss the critical role which new applications and tools, based on earth observation data and ICT technologies, have to play in transforming agricultural systems and ensuring the sustainable management of natural resources under current and future climate conditions. The address will highlight from many examples in Africa and Asia how these tools are currently being used to inform policy and investment decisions. This suite of data tools and databases for improved land and water management, have typically used innovative approaches to address data gaps and provide critically needed information to assess water availability and use. These developments have kept apace and harnessed rapidly developing advances in satellite and other sources of imagery as well as data modeling and analytical techniques. Applicable at global to regional scales, these data tools have included an earth observation-based approach to understanding just how much water is available and where/how this is being used on an operational basis in data scarce areas. This information is invaluable to water and agriculture planners and decision-makers, as they grapple with decreasing water availability and the growing impacts of climate change which is undermining the historical records they have relied on to date, to support their work. In recent advances, climate change scenarios have been used to develop an understanding of future trajectories of water accounts in a river basin and helps to answer the critical question of “Will there be water?” In many agricultural and natural resources management arenas, lack of data is cited as the major impediment to effective and realistic decision-making. Lisa’s drive to innovate approaches to filling that data gap has led to evidence-based informed strategic policy developments and day-to-day management of critical water resources across sectors in many African and Asian countries. Background: Dr Lisa-Maria Rebelo has been awarded the Derek Tribe Award for 2022 by the Crawford Fund. She has been recognized for her work across the African continent, and in South and Southeast Asia, in water productivity, remote sensing, natural resource management, wetland monitoring and assessment, basin water accounting, water productivity. The Derek Tribe Award was inaugurated in 2001 to mark the outstanding contributions of Emeritus Professor Derek Tribe AO OBE FTSE, Foundation Director of the Crawford Fund, to the promotion of international agricultural research. The Derek Tribe Award is made biennially to a citizen of a developing country in recognition of their distinguished contributions to the application of research in agriculture or natural resource management in a developing country or countries. The Crawford Fund is pleased to partner with Geosciences Australia to support Lisa-Maria to visit Australia to share her experiences and to deliver the 2022 Derek Tribe Address. Title: Digital Earth Africa: empowering African led solutions for climate action with Australian innovation - Geoscience Australia Distinguished Lecture Award Overview: Digital Earth Africa (DE Africa) is a flagship investment for the Australian aid program in Africa, deploying world-class Australian innovation at unprecedented scales to deliver development outcomes across the African continent. Since 2019, DE Africa has been delivered through successful African - Australian partnerships, with Australian innovation supporting African leadership to support sustainable development, as well as build resilience and adapt to climate change. By providing access to freely available, decision ready earth observation information, Digital Earth Africa is now supporting a diverse range of governments, communities and industry partners to make more informed decisions on topics of national significance, such as supporting community-led climate action through mangrove conservation in Tanzania, high-level government decision-making on unregulated mining in Ghana and giraffe conservation in Kenya. The new DE Africa Coastline monitoring tool enables users to analyse coastal erosion and growth trends on an annual basis, and is now being used by partners in Senegal to support climate adaptation and mitigation efforts. Leveraging innovation from DE Australia, DE Africa Coastlines exemplifies how global to regional scale earth observation-based tools can successfully empower locally led decision making. Other continent wide, earth observation based services available through DE Africa, include Water Observations from Space, a provisional Crop Extent map and Vegetation Fractional cover. These innovative tools have immense potential to fill key data gaps needed to improve assessments of water use and availability and to support agricultural and natural resources management across the African continent. Background: Cedric will be presenting this talk on behalf of the Digital Earth Africa establishment team as part of Geoscience Australia’s Distinguished Geoscience Australia Lecture series
-
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.
-
Combining observations of open water, wet vegetation, and vegetation fractional cover allows us to observe the spatiotemporal behaviour of wetlands. We developed a Wetlands Insight Tool (WIT) using Analysis-Ready Data available through Digital Earth Australia that combines Water Observations from Space (WOfS), the Tasseled Cap Wetness Transform (TCW) and Fractional Cover into an asset drill. We demonstrate the tool on three Australian wetlands, showing changes in water and vegetation from bush fires, sand mining and planned recovery. This paper was submitted to/presented at the 2019 IEEE International Geoscience and Remote Sensing Symposium (IGARSS 2019) - https://igarss2019.org/
-
Digital Earth Australia (DEA) is a key piece of public data infrastructure that uses images and information recorded by satellites orbiting our planet to detect physical changes across Australia in unprecedented detail. Landsat 5, 7 and 8 ‘analysis-ready’ data are currently available within DEA, where the raw satellite data have been corrected and orthorectified to enable easy interrogation of data across sensors. Geoscience Australia is developing techniques for analysing the data within DEA to identify wetlands and groundwater dependent ecosystems across northern Australia. These techniques include summarising observations of ‘wetness’ acquired over 30 years and linking these observations to gridded rainfall measurements to identity waterbodies and wetlands that persist during periods of low rainfall. These wetness summaries have been shown to correspond with known spring complexes in the Carmichael River catchment in Queensland, and have been used to improve the understanding of groundwater discharge processes within basalt provinces in the Upper Burdekin region in Queensland. This poster was submitted/presented to the 2018 Australian Geoscience Council Convention (AGCC) 14-18 October (https://www.agcc.org.au/)
-
60 second video announcing Digital Earth Australia - a world first analysis platform for satellite imagery and other Earth observations.
-
Groundwater-dependent ecosystems (GDEs) rely on access to groundwater on a permanent or intermittent basis for some or all of their water requirements (Queensland Government, 2018). Remotely sensed data from Digital Earth Australia (DEA) (Geoscience Australia, 2018) were used to map potential aquatic and other GDEs and enhance understanding of surface water – groundwater interactions in the Upper Burdekin region. Two Landsat TM satellite products (Water Observations from Space (WOfS; Mueller et al. 2016) summary statistic and Tasselled Cap Index (TCI) wetness summary)) were used to investigate the persistence of surface water and soil moisture in the landscape to identify perennial streams, springs and other parts of the landscape that may rely on groundwater discharge. 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 at least 25 m wide 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, such as the identification of standing water for at least 80% of the time. The TCI is a method of reducing six surface reflectance bands of satellite data to three bands (Brightness, Greenness, Wetness) using a Principal Components Analysis (PCA) and Procrustes' Rotation (Roberts et al., 2018). The published coefficients of Crist (1985) are applied to DEA's Landsat data to generate a TCI composite. The resulting Tasselled Cap bands are a linear combination of the original surface reflectance bands that correlate with the Brightness (bare earth), Greenness and Wetness of the landscape. The TCI wetness summary (or Tasselled Cap Wetness (TCW) percentage exceedance composite), derived from the Wetness band, represents the behaviour of water in the landscape, as defined by the presence of water, moist soil or wet vegetation at each pixel through time. The summary shows the percentage of observed scenes where the Wetness layer of the Tasselled Cap transform is above the threshold, i.e. where each pixel has been observed as ‘wet’ according to the TCI. Areas that retain surface water or wetness in the landscape during the dry season are potential areas of groundwater discharge and associated GDEs. The TCW threshold is set at -600 to calculate the percentage exceedance. This threshold is based on scientific judgment and is currently in the research/testing phase. It is based on Australian conditions and conservative in nature. The dry season, when surface runoff to streams and rainfall are minimal, is particularly useful for identifying and mapping groundwater-fed streams, springs and other ecosystems that rely on access to groundwater during periods of limited rainfall. The Upper Burdekin region was especially dry between May and October 2013, with low rainfall totals in the months preceding this dry season and overall below-average rainfall conditions (i.e. decline in rainfall residual mass). The TCW exceedance composite was classified into percentage intervals to distinguish areas that were wet for different proportions of time during the 2013 dry season. Field validation of the remote sensing data products would be required to confirm the preliminary identification of parts of the landscape where groundwater discharges to the surface and potentially supports GDEs. This release includes the classified WOfS summary statistic and classified TCW percentage exceedance composite (May-October 2013) data products for the McBride and Nulla basalt provinces in the Upper Burdekin region, North Queensland. <b>References: </b> Crist EP (1985) A TM Tasseled Cap equivalent transformation for reflectance factor data. Remote Sensing of Environment 17(3), 301–306. Doi: 10.1016/0034-4257(85)90102-6. Geoscience Australia (2018) Digital Earth Australia. Geoscience Australia, http://www.ga.gov.au/dea. Mueller, N., Lewis, A., Roberts, D., Ring, S., Melrose, R., Sixsmith, J., Lymburner, L., McIntyre, A., Tan, P., Curnow, S. and Ip, A. (2016) Water observations from space: Mapping surface water from 25 years of Landsat imagery across Australia. Remote Sensing of Environment 174, 341-352, ISSN 0034-4257. Queensland Government (2018) Groundwater dependent ecosystems, WetlandInfo 2014. Queensland Government, Brisbane, https://wetlandinfo.des.qld.gov.au/wetlands/ecology/aquatic-ecosystems-natural/groundwater-dependent/. Roberts D, Dunn B and Mueller N (2018) Open Data Cube Products Using High-Dimensional Statistics of Time Series. International Geoscience and Remote Sensing Symposium. Valencia, Spain: IEEE Geoscience and Remote Sensing Society.
-
Record for source data - Calibration & Validation Surface Reflectance Measurements for the National Spectral Database (NSD). This is a collection of Phase 1 & Phase 2 datasets from Geoscience Australia Analysis Ready Data (ARD) Calibration & Validation's field program. The data is intended to serve the GA ARD surface reflectance validation pipeline. Phase 1 field campaigns are summarised in the technical report: Byrne, G., Walsh, A., Thankappan, M., Broomhall, M., Hay, E. 2021. DEA Analysis Ready Data Phase 1 Validation Project : Data Summary. Geoscience Australia, Canberra. doi.org/10.26186/145101
-
Digital Earth Australia (DEA) is a world-class digital infrastructure that uses satellite data, in the form of images and information, to detect physical changes across Australia in unprecedented detail. It identifies soil and coastal erosion, crop growth, water quality and changes to cities and regions. DEA provides government, industry, and individuals with the high-quality data and tools required for policy and investment decision-making. DEA will support industry productivity and innovation and the development of new digital products and services. These capabilities will improve decision-making, increase business efficiency, bolster profits and create jobs. For more information visit www.ga.gov.au/dea
-
Factsheet for DEA with information relevant to stakeholders from the Australian Government