From 1 - 6 / 6
  • Categories    

    Turbidity is a measure of water clarity that quantifies the amount of small particles suspended in the water, and is a fundamental environmental parameter influencing coastal marine ecosystems. Turbidity reduces the light needed for photosynthesis by corals and seagrasses, and suspended particles also transport nutrients, pollutants and diseases. Previous research based on 3 years of turbidity data collected from 15 inshore reefs by the Reef Rescue Marine Monitoring Program has shown that it can take several months for water clarity to improve after river floods. This project will analyse a 12-year data set to demonstrate the explicit link between variations in discharge (sediments and nutrients) from the major rivers in each Natural Resource Management (NRM) region adjacent to the Great Barrier Reef (GBR) and seasonal and annual variations in water clarity in the inshore GBR. This project will: 1. Determine quantitative relationships between river discharges and seasonal and annual variation in inshore water clarity on the GBR adjacent to each NRM region. This is achieved by processing MODIS/Aqua remote sensing (since July 2002) to calculate euphotic depth (water clarity) for the whole GBR and analysing this against predicted and observed tides, observed waves, wind, rain, river flow data (BOM and DERM daily data) and tidal forcing (Slim model). 2. Strengthen scientific basis for Reef Rescue and Reef Plan and the refinement of water quality targets. 3. Provide data to assist validation and calibration of the Receiving Waters Model and a WQ Risk Analysis. This project is now complete.

  • Categories    

    Natural Earth is a public domain map dataset available at 1:10m, 1:50m, and 1:110 million scales. Featuring tightly integrated vector and raster data, with Natural Earth you can make a variety of visually pleasing, well-crafted maps with cartography or GIS software. Natural Earth was built through a collaboration of many volunteers and is supported by NACIS (North American Cartographic Information Society). Natural Earth Vector comes in ESRI shapefile format, the de facto standard for vector geodata. Character encoding is Windows-1252. Natural Earth Vector includes features corresponding to the following: Cultural Vector Data Thremes: - Countries: matched boundary lines and polygons with names attributes for countries and sovereign states. Includes dependencies (French Polynesia), map units (U.S. Pacific Island Territories) and sub-national map subunits (Corsica versus mainland Metropolitan France). - Disputed areas and breakaway regions - From Kashmir to the Elemi Triangle, Northern Cyprus to Western Sahara. - First order admin (provinces, departments, states, etc.): internal boundaries and polygons for all but a few tiny island nations. Includes names attributes and some statistical groupings of the same for smaller countries. - Populated places: point symbols with name attributes. Includes capitals, major cities and towns, plus significant smaller towns in sparsely inhabited regions. We favor regional significance over population census in determining rankings. - Urban polygons: derived from 2002-2003 MODIS satellite data. - Parks and protected areas: US National Park Service units. - Pacific nation groupings: boxes for keeping these far-flung islands tidy. - Water boundary indicators: partial selection of key 200-mile nautical limits, plus some disputed, treaty, and median lines. Physical Vector Data Themes: - Coastline: ocean coastline, including major islands. Coastline is matched to land and water polygons. - Land: Land polygons including major islands - Ocean: Ocean polygon split into contiguous pieces. - Minor Islands: additional small ocean islands ranked to two levels of relative importance. - Reefs: major coral reefs from WDB2. - Physical region features: polygon and point labels of major physical features. - Rivers and Lake Centerlines: ranked by relative importance. Includes name and line width attributes. Don’t want minor lakes? Turn on their centerlines to avoid unseemly data gaps. - Lakes: ranked by relative importance, coordinating with river ranking. Includes name attributes. - Glaciated areas: polygons derived from DCW, except for Antarctica derived from MOA. Includes name attributes for major polar glaciers. - Antarctic ice shelves: derived from 2003-2004 MOA. Reflects recent ice shelf collapses. - Bathymetry: nested polygons at 0, -200, -1,000, -2,000, -3,000, -4,000, -5,000, -6,000, -7,000, -8,000, -9,000,and -10,000 meters. Created from SRTM Plus. - Geographic lines: Polar circles, tropical circles, equator, and International Date Line. - Graticules: 1-, 5-, 10-, 15-, 20-, and 30-degree increments. Includes WGS84 bounding box.

  • Categories    

    The Wet Tropics World Heritage Area (WTWHA) is famous for its wildlife, biodiversity and natural beauty, but none of these important assets are bought or sold in the market place, so none are explicitly ‘valued’ with a price. Recognising that absence of price does not mean absence of value, this project seeks to improve our understanding of the importance of these non-market ‘values’ to a variety of different stakeholders. How important is a beautiful view or a cassowary to the community, to tourists and to the tourism industry? How would people feel if there fewer (or more) opportunities to enjoy those beautiful views or to observe these charismatic birds? The project will provide environmental managers throughout the world with an illustrated, easy to understand, means of assessing the importance of these types of non-market values to a variety of different stakeholder groups in World Heritage listed forests and other scenic environments. This project will: 1. Develop a survey to assess the relative importance of core 'values' of the WTWHA (e.g. cassowaries, mahogany sugar gliders, waterfalls, aesthetics) with other ‘values’ (e.g. development of roads, employment, or income) so that managers are able to assess trade-offs between core WTWHA attributes and other ‘values’. 2. Distribute the questionaire to residents (householders) throughout the WTWHA and to tourists at the Cairns airport at different times of the year (to control for seasonality of data) in the form of an exit survey; 3. To analyse the results using multivariate analysis to measure the satisfaction and relative value across different stakeholder groups and to use insights from this analysis to identify priorities for conservation and marketing.

  • Categories    

    This project focuses on relationships between socio-economic systems and the Great Barrier Reef (GBR). It comprises three interrelated activities to investigate: 1. Resident and tourist views about the relative ‘value’ of key ecosystem services that are provided by the reef. Researchers will design, distribute and analyse the results of a survey instrument to assess the relative value of different goods and services produced by the GBR to stakeholder groups using both traditional money-based valuation techniques and Larson’s non-monetary based technique. 2. Tourist views about the relative value of key attributes of reef health, and the likely consequence if reef health deteriorates such as fewer visits and less expenditure. 3. Researchers will develop proxies for rainfall, water quality, land use and economy at the catchment scale. Analyses of these data will be used to determine the extent to which variations in beef prices, the exchange rate and other socio-economic variables (in conjunction with biophysical variables) influence water quality in the GBR lagoon.

  • Categories    

    This phase of Project 3DGBR involved manual digitising of geomorphic map boundaries for the key seafloor features identified in the gbr100 grid, particularly for the inter-reefal area on the GBR shelf and in the Coral Sea Conservation Zone (CSCZ). See map for CSCZ boundary at: https://www.environment.gov.au/topics/marine/marine-reserves/coral-sea/conservation-zone Methods: GIS spatial analysis of the gbr100 grid was conducted in order to derive a number of useful background datasets for assisting in the digitising process, such as slope, aspect, hillshading, and dense contour lines. The digitising initially focused on the deep-water (>100 m) environment to develop geomorphic maps for the continental slope, Queensland and Townsville Troughs lying within the Great Barrier Reef World Heritage Area (GBRWHA), and for the Queensland Plateau, Coral Sea Basin, Tasman Basin, and Lord Howe Rise area lying within the adjoining Coral Sea Conservation Zone (CSCZ). The project lastly focuses on the shallow-water (<100 m) environment to develop geomorphic maps for the GBR shelf to complement the shallow reef feature maps provided by GBRMPA. These shallow-water geomorphic features will be added to the project as they come available. Format: This dataset consists of 21 shapefiles and a GeoTiff raster file containing hillshading. Each of the shapefiles is described below. Group Layer 1. Boundaries: gbrwha_outer.shp This Great Barrier Reef World Heritage Area (GBRWHA) layer was initially provided by GBRMPA using a GDA94 datum. The shapefile was reprojected to the WGS84 datum, and then the western coastline boundaries deleted to derive a line shapefile showing only the outer boundary of the GBRWHA where it extends away from the mainland. qld_gbrwha_cscz.shp This line shapefile combines both the GBRWHA and Coral Sea Conservation Zone (CSCZ) areas, with a western boundary limit at the Queensland mainland coastline. This area was used to clip all geomorphic features created in this project. Group Layer 2. GBRMPA features: gbr_dryreef.shp The GBR shelf dryreefs shapefile was initially provided by GBRMPA for this project using a GD94 datum. The shapefile was reprojected to the WGS84 datum and not modified in any other way. It is provided here only for completeness but and products using this shapefile should also acknowledge GBRMPA (see under licensing). gbr_features.shp The GBR shelf features were initially provided by GBRMPA for this project using a GDA94 datum. The shapefile was reprojected to the WGS84 datum, and then the Ashmore Reef polygon deleted due to a grossly incorrect position. The shapefile comprises Cay, Island, Mainland, Reef, Rock and Sand features. Users may contact GBRMPA to obtain details for the creation of these features. Any products using this shapefile should also acknowledge GBRMPA (see under licensing). Group Layer 3. Finer-scale features: coralsea_cay.shp Cay is a sand island elevated above Australian Height Datum (AHD), and located on offshore coral reefs and seamounts. Cays were mapped initially using a shapefile provided by Geoscience Australia for this project, and then their boundaries checked or remapped using Landsat imagery as background source data to help delineate the white sand areas against the surrounding ocean. coralsea_dryreef.shp Dryreef is rock/coral lying at or near the sea surface that may constitute a hazard to surface navigation. Dryreefs were mapped initially using a shapefile provided by Geoscience Australia for this project, which identified those reef areas lying above approximately Lowest Astronomic Tide (LAT). Landsat imagery was used as background source data to check or remap their boundaries. coralsea_reef.shp Reef is rock/coral lying at or near the sea surface that may constitute a hazard to surface navigation. For this project, the boundaries of reef areas were mapped to show the outer-most extent of each coral reef that could be observed in Landsat imagery, thus identifying the greatest area of each reef observed in the Coral Sea. This methodology is consistent with the methodology used to map the outer-most extents of reefs on the GBR shelf conducted by GBRMPA. coralsea_ridge.shp Ridge is a long, narrow elevation with steep sides. In this project, ridges were mapped as widely-scattered and uncommon, finer-scale features identified in the gbr100 grid. These elongate ridges are distinct from the smaller knolls or hills which have a more rounded shape. They are usually found on the plateaus of the Lord Howe Rise. coralsea_bank.shp Bank is an elevation over which the depth of water is relatively shallow but normally sufficient for safe surface navigation. In this project, banks were mapped as the base or pedestal boundaries of the coral reefs found in the Coral Sea. For example, the coral atolls and reefs on the Queensland Plateau are considered banks and their bases digitised where they emerge from the surrounding flat seafloor. coralsea_knoll.shp Knoll is a relatively small isolated elevation of a rounded shape. This shapefile also includes Abyssal hill, a low (100 – 500 m) elevation on the deep seafloor. For this project, knolls and abyssal hills were mapped using background datasets that showed relatively steep changes in elevation contours and variations in slope gradients. Knolls are numerous throughout the Coral Sea area and are greatly underestimated. coralsea_canyon.shp Canyon is a relatively narrow, deep depression with steep sides, the bottom of which generally has a continuous slope, developed characteristically on continental slopes. Canyons were mapped by closely following the narrow sides of canyon axes, digitising from the foot of the canyon where they merge with the surrounding basin floor, and up to the canyon head and into any connecting side gullies. This project identified numerous canyons on any slope gradient >1° and are also greatly underestimated across the area. coralsea_seamount.shp Seamount is a large isolated elevation >1000 m in relief above the seafloor, characteristically of conical form. This shapefile also includes Guyot, a seamount having a comparatively smooth flat top. Seamounts and guyots were mapped mostly within the Tasmantid Seamount Chain with elevations >1000 m. This project identified several large knolls and hills close to 1000 m in height within this chain that may also be seamounts but currently lack detailed bathymetry data. Group Layer 4. Broader-scale features: gbr_shelf.shp Shelf is a zone adjacent to a continent (or around an island) extending from the low water line to a depth at which there is usually a marked increase of slope towards oceanic depths. The eastern boundary of the Queensland continental shelf was mapped by closely following the change in gradient along the shelf edge. The shelf break in the north was at approximately 80 m and became deeper at about 110 m towards the south. The western boundary was clipped at the Queensland mainland coastline. coralsea_slope.shp Slope lies seaward from the shelf edge to the upper edge of a continental rise or the point where there is a general reduction in slope. The continental slope was mapped lying adjacent to the shelf and extending into the adjacent deep basins and troughs. The shelf feature was used to erase the western boundary of the slope and the various basins and troughs erased the eastern slope border. The slope has extensive canyons incising its surface. coralsea_terrace.shp Terrace is a relatively flat horizontal or gently inclined surface, sometimes long and narrow, which is bounded by a steeper ascending slope on one side and by a steeper descending slope on the opposite side. In this project, one broad-scale terrace feature was mapped lying on the slope between the Swains Reefs and Capricorn-Bunker Group of reefs, and near the Capricorn Trough. coralsea_plateau.shp Plateau is a flat or nearly flat area of considerable extent, dropping off abruptly on one or more sides. Extensive areas of plateaus were mapped across the Coral Sea with the largest being the Queensland Plateau. Lord Howe Rise consists of a series of plateaus separated by broad-scale valleys linking adjacent basins and troughs. Plateau boundaries were mapped around their bases where the gradient first becomes steeper. The exceptions are the Marion and Saumarez Plateaus on the Queensland continental slope, where the boundaries were mapped as the slope gradient becomes flat or nearly flat. coralsea_valley.shp Valley is a relatively shallow, wide depression, the bottom of which usually has a continuous gradient. This term is generally not used for features that have canyon-like characteristics for a significant portion of their extent. The shapefile includes Hole, a local depression, often steep sided, of the seafloor. Valleys and holes were mapped as long shallow depressions that often separated the numerous plateaus. These features link the basins and troughs that surround these plateaus, and in some cases can be incised with finer-scale canyons. coralsea_trough.shp Trough is a long depression of the seafloor characteristically flat bottomed and steep sided and normally shallower than a trench. In this project, two trough features were mapped that are essentially long basins. The larger feature is a combined Queensland and Townsville Trough lying between the continental slope and the Queensland Plateau. The smaller feature is the Bligh Trough separating the northern slope and Eastern Plateau. Both trough features feed into the Osprey Embayment and huge Bligh Canyon. coralsea_rise.shp Rise is a gentle slope rising from the oceanic depths towards the foot of a continental slope. For this project, an elongate rise is mapped between the Queensland Plateau and the adjacent Coral Sea Basin. The Queensland Plateau is remnant continental crust from the Gondwana breakup and so its seaward edge provides a geomorphic extension of the Australian margin, albeit at a much deeper depth than the present mainland margin. The rise was mapped where the gradient angle of the Queensland Plateau seaward edge first becomes less steep and finishes at the Coral Sea Basin abyssal plain. Another rise feature was mapped between the southern continental slope and the Tasman Basin abyssal plain. coralsea_basin.shp Basin is a depression, characteristically in the deep seafloor, more or less equidimensional in plan and of variable extent. Basins were mapped where their boundaries changed from generally flat to more steep gradients. Plateau or slope features were used to erase and limit the boundaries of the basin features. In the north lies the large Osprey Embayment which has smaller plateaus lying within its area. The Cato Trough is a large basin separating the southern continental slope and plateaus of the Lord Howe Rise area. On the Lord Howe Rise are shallow basins that surround the series of plateaus that lie on the Lord Howe Rise. coralsea_abyssalplain.shp Abyssal plain is an extensive, flat, gently sloping or nearly level region at abyssal depths. Three abyssal plains were mapped where their gradients became generally flat and at depths greater than about 4000 m. In the north are the abyssal plains of the Coral Sea Basin and Louisiade Basin, the latter being a failed arm of a rift triple junction. In the south, lies the abyssal plain of the Tasman Basin. Group Layer 5. Background image: gbr100_geo3.tif This hillshade geotif image was derived from the gbr100 grid using Fledermaus 3D visualization software with a depth colour scheme configured to highlight the physiographic relief of the shallow shelf and the deeper seabed features. It is provided here to give geomorphic context to the seabed areas lying outside of the GBRWHA and CSCZ. Funding: Queensland Government Smart Futures Fellowship Reef and Rainforest Research Centre James Cook University References: Heap, A.D., Harris, P.T., 2008. Geomorphology of the Australian margin and adjacent seafloor. Australian Journal of Earth Sciences 55(4), 555-585. doi: 10.1080/08120090801888669 IHO, 2008. Standardization of Undersea Feature Names: Guidelines, Proposal Form, Terminology. Bathymetric Publication No.6, 4th Edition, International Hydrographic Bureau/Intergovernmental Oceanographic Commission, Monaco, pp. 32. Change log: 2023-01-10 - Updated the dataset download link from the original JCU link that is broken (http://ftt.jcu.edu.au/deepreef/3dgbr/geo/3dgbr_geomorph.zip) to a cached version hosted by the eAtlas.

  • Categories    

    This dataset corresponds to a reformatting of the SRTM30_PLUS digital elevation dataset from 33 NetCDF files into a single GeoTiff for use in GIS applications. No other modifications to the data were done. The rest of this metadata describes the original SRTM30_PLUS dataset itself. Note: The SRTM15_plus dataset is a similar more recent, higher resolution bathymetry dataset https://topex.ucsd.edu/WWW_html/srtm15_plus.html. This dataset is a 30-arc second resolution global topography/bathymetry grid (SRTM30_PLUS) developed from a wide variety of data sources. Land and ice topography comes from the SRTM30 and ICESat topography, respectively. Ocean bathymetry is based on a new satellite-gravity model where the gravity-to-topography ratio is calibrated using 298 million edited soundings. The main contribution of this dataset is the compilation and editing of the raw soundings, which come from NOAA, individual scientists, SIO, NGA, JAMSTEC, IFREMER, GEBCO, and NAVOCEANO. The SRTM30_PLUS dataset developed by Scripps Institute Of Oceanography, University of California San Diego (UCSD). Land data are based on the 1-km averages of topography derived from the USGS SRTM30 grided DEM data product created with data from the NASA Shuttle Radar Topography Mission. GTOPO30 data are used for high latitudes where SRTM data are not available. Ocean data are based on the Smith and Sandwell global 1-minute grid between latitudes +/- 81 degrees. Higher resolution grids have been added from the LDEO Ridge Multibeam Synthesis Project, the JAMSTEC Data Site for Research Cruises, and the NGDC Coastal Relief Model. Arctic bathymetry is from the International Bathymetric Chart of the Oceans (IBCAO) [Jakobsson et al., 2003]. This data consists of 33 files of global topography in the same format as the SRTM30 products distributed by the USGS EROS data center. The grid resolution is 30 second which is roughly one kilometer. In addition the global data are also available in a single large file ready for GMT and as 33 NetCDF files. The eAtlas has also merged and formatted the data as a single GeoTiff file with overviews (1.6 GB). The pixel-registered data are stored in 33 files with names corresponding to the upper left corner of the array shown below. The data are also merged into a single large (1.9 Gbyte, 2-byte integer) file as well as smaller 1-minute and 2-minute netcdf versions. Matching files of source identification number are available for determining the data source for every pixel. This new version (v8.0) includes all of the multibeam bathymetry data collected by U.S. research vessels over the past three decades including 287 Scripps expeditions from research vessels Washington, Melville and Revelle. UCSD undergraduate student Alexis Shakas processed all the U.S. multibeam data and then worked with Google researchers on the global integration. The data is available from UCSD FTP server as 33 NetCDF files and from the eAtlas as a merged GeoTiff. If you are after high resolution bathymetry/elevation data for regional areas please check the related links. Reference, sounding data: Becker, J. J., D. T. Sandwell, W. H. F. Smith, J. Braud, B. Binder, J. Depner, D. Fabre, J. Factor, S. Ingalls, S-H. Kim, R. Ladner, K. Marks, S. Nelson, A. Pharaoh, R. Trimmer, J. Von Rosenberg, G. Wallace, P. Weatherall., Global Bathymetry and Elevation Data at 30 Arc Seconds Resolution: SRTM30_PLUS, Marine Geodesy, 32:4, 355-371, 2009. http://topex.ucsd.edu/sandwell/publications/124_MG_Becker.pdf Reference, gravity data: Sandwell, D. T., and W. H. F. Smith, Global marine gravity from retracked Geosat and ERS-1 altimetry: Ridge Segmentation versus spreading rate, J. Geophys. Res., 114, B01411, doi:10.1029/2008JB006008, 2009. http://dx.doi.org/10.1029/2008JB006008 eAtlas Processing: A set of Batch scripts were developed to perform the conversion of the data from NetCDF to GeoTiff and the generation of the hillshading. This processing was based on the GDAL command line tools. Full details of the processing can be found in the downloadable Scripts associated with this dataset. Data Location: This dataset is filed in the eAtlas enduring data repository at: data\NERP-TE\13.1_eAtlas\World_UCSD_SRTM30-plus