تم استخلاص "نموذج الارتفاع الرقمي" (DEM-S) المعدّل من بيانات SRTM التي حصلت عليها وكالة ناسا في شباط (فبراير) 2000. تمثّل بيانات DEM-S تضاريس سطح الأرض (باستثناء ميزات الغطاء النباتي)، وتمت تسويتها لتقليل الضوضاء وتحسين تمثيل شكل السطح. عملية تكيفية يتم فيها تطبيق تجانس أكبر في المناطق المسطحة مقارنةً بالمناطق الجبلية، وتطبيق تجانس أكبر في المناطق الأكثر ضوضاءً مقارنةً بالمناطق الأقل ضوضاءً.
يدعم نموذج الارتفاع الرقمي هذا احتساب سمات شكل التضاريس المحلية، مثل الانحدار والاتجاه والانحناء، التي لا يمكن استخلاصها بشكل موثوق من نموذج الارتفاع الرقمي غير المُعدَّل الذي تبلغ دقته ثانية واحدة بسبب التشويش.
هناك عدّة مناطق تتضمّن قيمًا سالبة غير متوقّعة: بالقرب من كانبيرا حول (150.443044، -35.355281) بقيم تبلغ -55، وفي غرب أستراليا حول (124.84، -16.44) بقيم تبلغ -43.
تم استخلاص "نموذج الارتفاع الرقمي المعدّل" (DEM-S) من بيانات "مهمة طوبوغرافيا المكوك الفضائي" (SRTM) التي حصلت عليها وكالة ناسا في شباط (فبراير) 2000. تمثّل DEM-S تضاريس سطح الأرض (باستثناء ميزات الغطاء النباتي) وتم تنعيمها لتقليل الضوضاء وتحسين تمثيل شكل السطح. تطبّق عملية التكيّف تجانسًا أكبر في المناطق الأكثر تسطحًا من …
[null,null,[],[[["\u003cp\u003eThe DEM-S is a smoothed digital elevation model of Australia derived from SRTM data acquired in February 2000.\u003c/p\u003e\n"],["\u003cp\u003eIt represents ground surface topography, excluding vegetation, and has been smoothed to reduce noise and improve surface shape representation.\u003c/p\u003e\n"],["\u003cp\u003eThe DEM-S has a resolution of 30.92 meters and includes an elevation band, with potential negative values in specific areas.\u003c/p\u003e\n"],["\u003cp\u003eThis dataset is available under the CC-BY-4.0 license and is provided by Geoscience Australia.\u003c/p\u003e\n"],["\u003cp\u003eIt is suitable for calculating terrain shape attributes like slope, aspect, and curvature.\u003c/p\u003e\n"]]],[],null,["# DEM-S: Australian Smoothed 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 Smoothed Digital Elevation Model (DEM-S) was derived\nfrom the SRTM data acquired by NASA in February 2000. DEM-S represents\nground surface topography (excluding vegetation features) and has\nbeen smoothed to reduce noise and improve the representation of\nsurface shape. An adaptive process applied more smoothing in flatter\nareas than hilly areas, and more smoothing in noisier areas than\nin less noisy areas.\n\nThis DEM-S supports calculation of local terrain shape attributes\nsuch as slope, aspect, and curvature that could not be reliably\nderived from the unsmoothed 1 second DEM because of noise.\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 | -73.31\\* | 2224.32\\* | 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-S');\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-S) \n[DEM-S: Australian Smoothed Digital Elevation Model](/earth-engine/datasets/catalog/AU_GA_DEM_1SEC_v10_DEM-S) \nThe Smoothed Digital Elevation Model (DEM-S) was derived from the SRTM data acquired by NASA in February 2000. DEM-S represents ground surface topography (excluding vegetation features) and has been smoothed to reduce noise and improve the representation of surface shape. An adaptive process applied more smoothing in flatter areas than ... \nAU/GA/DEM_1SEC/v10/DEM-S, 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-S)"]]
