Le modèle numérique d'élévation à contraintes hydrologiques (DEM-H) a été dérivé des données SRTM acquises par la NASA en février 2000. Le modèle a été conditionné hydrologiquement et le drainage a été appliqué. Le DEM-H capture les chemins de flux en fonction des altitudes SRTM et des lignes de flux cartographiées, et permet de délimiter les bassins versants et les attributs hydrologiques associés. L'ensemble de données a été dérivé du modèle numérique d'élévation lissé à une seconde (DEM-S ; ANZCW0703014016) en appliquant la connectivité hydrologique avec le logiciel ANUDEM, en utilisant les lignes de cours d'eau AusHydro V1.6 (février 2010) à l'échelle 1:250 000 sélectionnées (ANZCW0503900101) et les lignes dérivées de DEM-S pour définir les cours d'eau. L'application du drainage a permis d'obtenir une représentation cohérente de la connectivité hydrologique, avec quelques artefacts d'altitude résultant de l'application du drainage. Une description complète des méthodes est en préparation (Dowling et al., in prep).
Ce produit fournit un MNT adapté à l'analyse hydrologique, comme la définition du bassin versant et le routage du flux.
Plusieurs zones présentent des valeurs négatives inattendues : près de Canberra, autour de (150.443044, -35.355281) avec des valeurs de -55, et en Australie-Occidentale, autour de (124.84, -16.44) avec -43.
Le modèle numérique d'élévation (DEM-H) à contraintes hydrologiques a été dérivé des données SRTM acquises par la NASA en février 2000. Le modèle a été conditionné hydrologiquement et le drainage a été appliqué. Le DEM-H capture les chemins de flux en fonction des altitudes SRTM et des lignes de flux cartographiées, et permet de délimiter les bassins versants et les attributs hydrologiques associés. …
[null,null,[],[[["\u003cp\u003eThe Hydrologically Enforced Digital Elevation Model (DEM-H) of Australia was derived from NASA's SRTM data and has been hydrologically conditioned for drainage enforcement.\u003c/p\u003e\n"],["\u003cp\u003eDEM-H supports hydrological analysis, such as catchment definition and flow routing, by capturing flow paths based on SRTM elevations and mapped stream lines.\u003c/p\u003e\n"],["\u003cp\u003eThis DEM, with a resolution of 30.92 meters, covers Australia and has a Creative Commons Attribution 4.0 license.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset was produced by Geoscience Australia and is available in Earth Engine with an elevation band ranging from approximately -31 to 2223 meters.\u003c/p\u003e\n"]]],[],null,["# DEM-H: Australian SRTM Hydrologically Enforced Digital Elevation Model\n\nDataset Availability\n: 2010-02-01T00:00:00Z--2010-02-01T00:00:00Z\n\nDataset Provider\n:\n\n\n [Geoscience Australia](https://www.ga.gov.au/metadata-gateway/metadata/record/72759/)\n\nTags\n:\n[australia](/earth-engine/datasets/tags/australia) [dem](/earth-engine/datasets/tags/dem) [elevation](/earth-engine/datasets/tags/elevation) [elevation-topography](/earth-engine/datasets/tags/elevation-topography) [ga](/earth-engine/datasets/tags/ga) [geophysical](/earth-engine/datasets/tags/geophysical) [geoscience-australia](/earth-engine/datasets/tags/geoscience-australia) [smoothed](/earth-engine/datasets/tags/smoothed) [srtm](/earth-engine/datasets/tags/srtm) \n\n#### Description\n\nThe Hydrologically Enforced Digital Elevation Model\n(DEM-H) was derived from the SRTM data acquired by NASA in February\n2000. The model has been hydrologically conditioned and drainage\nenforced. The DEM-H captures flow paths based on SRTM elevations\nand mapped stream lines, and supports delineation of catchments\nand related hydrological attributes. The dataset was derived from\nthe 1 second smoothed Digital Elevation Model (DEM-S; ANZCW0703014016)\nby enforcing hydrological connectivity with the ANUDEM software,\nusing selected AusHydro V1.6 (February 2010) 1:250,000 scale watercourse\nlines (ANZCW0503900101) and lines derived from DEM-S to define\nthe watercourses. The drainage enforcement has produced a consistent\nrepresentation of hydrological connectivity with some elevation\nartifacts resulting from the drainage enforcement. A full description\nof the methods is in preparation (Dowling et al., in prep).\n\nThis product provides a DEM suitable for use in hydrological analysis\nsuch as catchment definition and flow routing.\n\nThere are several areas with unexpected negative values: close to\nCanberra around (150.443044, -35.355281) with values of -55 and in Western\nAustralia around (124.84, -16.44) with -43.\n\n### Bands\n\n\n**Pixel Size**\n\n30.92 meters\n\n**Bands**\n\n| Name | Units | Min | Max | Pixel Size | Description |\n|-------------|-------|----------|-----------|------------|-------------|\n| `elevation` | m | -31.37\\* | 2223.24\\* | meters | Elevation |\n\n\\* estimated min or max value\n\n### Terms of Use\n\n**Terms of Use**\n\n[CC-BY-4.0](https://spdx.org/licenses/CC-BY-4.0.html)\n\n### Citations\n\nCitations:\n\n- Geoscience Australia, 2015. Digital Elevation Model (DEM) of Australia\n derived from LiDAR 5 Metre Grid. Geoscience Australia, Canberra.\n\n### Explore with Earth Engine\n\n| **Important:** Earth Engine is a platform for petabyte-scale scientific analysis and visualization of geospatial datasets, both for public benefit and for business and government users. Earth Engine is free to use for research, education, and nonprofit use. To get started, please [register for Earth Engine access.](https://console.cloud.google.com/earth-engine)\n\n### Code Editor (JavaScript)\n\n```javascript\nvar dataset = ee.Image('AU/GA/DEM_1SEC/v10/DEM-H');\nvar elevation = dataset.select('elevation');\nvar elevationVis = {\n min: -10.0,\n max: 1300.0,\n palette: [\n '3ae237', 'b5e22e', 'd6e21f', 'fff705', 'ffd611', 'ffb613', 'ff8b13',\n 'ff6e08', 'ff500d', 'ff0000', 'de0101', 'c21301', '0602ff', '235cb1',\n '307ef3', '269db1', '30c8e2', '32d3ef', '3be285', '3ff38f', '86e26f'\n ],\n};\nMap.setCenter(133.95, -24.69, 5);\nMap.addLayer(elevation, elevationVis, 'Elevation');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/AU/AU_GA_DEM_1SEC_v10_DEM-H) \n[DEM-H: Australian SRTM Hydrologically Enforced Digital Elevation Model](/earth-engine/datasets/catalog/AU_GA_DEM_1SEC_v10_DEM-H) \nThe Hydrologically Enforced Digital Elevation Model (DEM-H) was derived from the SRTM data acquired by NASA in February 2000. The model 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. ... \nAU/GA/DEM_1SEC/v10/DEM-H, australia,dem,elevation,elevation-topography,ga,geophysical,geoscience-australia,smoothed,srtm \n2010-02-01T00:00:00Z/2010-02-01T00:00:00Z \n-44.06 112.99 -9.99 154 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [](https://doi.org/https://www.ga.gov.au/metadata-gateway/metadata/record/72759/)\n- [](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/AU_GA_DEM_1SEC_v10_DEM-H)"]]