HydroSHEDS, bölgesel ve küresel ölçekli uygulamalar için tutarlı bir biçimde hidrografik bilgiler sağlayan bir harita çıkarma ürünüdür. Nehir ağları, su havzası sınırları, drenaj yönleri ve akış birikimleri dahil olmak üzere çeşitli ölçeklerde coğrafi referanslı veri kümeleri (vektör ve raster) sunar. HydroSHEDS, NASA'nın 2000 yılında Shuttle Radar Topography Mission (SRTM) tarafından elde edilen yükseklik verilerine dayanmaktadır.
Bu drenaj yönü veri kümesi, koşullandırılmış DEM'deki her hücreden en dik aşağı eğimli komşusuna doğru akış yönünü tanımlar. Drenaj yönü değerleri 1 ile 128 arasında değişir. Okyanusa giden tüm son çıkış hücreleri 0 değeriyle işaretlenir. Kapalı bir havzanın (iç kısımda kalan çöküntü) en düşük noktasını işaretleyen tüm hücreler -1 değeriyle işaretlenir. Drenaj yönü değerleri, ESRI'nın akış yönü uygulaması tarafından benimsenen kurala uyar: 1=E, 2=SE, 4=S, 8=SW, 16=W, 32=NW, 64=N, 128=NE.
Bu veri kümesi, 30 yay saniyesi çözünürlüğe sahiptir.
30 yay saniyesi çözünürlükte kullanılabilen veri kümeleri; Hidrolojik Olarak Koşullandırılmış DEM, Drenaj (Akış) Yönü ve Akış Birikimi'dir.
HydroSHEDS verilerinin kalitesinin, 60 derece kuzey enleminin üzerindeki bölgelerde önemli ölçüde daha düşük olduğunu unutmayın. Bunun nedeni, temel SRTM yükseklik verilerinin olmaması ve bu nedenle daha kaba çözünürlüklü bir DEM'in (USGS tarafından sağlanan HYDRO1k) kullanılmasıdır.
HydroSHEDS, Dünya Doğayı Koruma Vakfı (WWF) Koruma Bilimi Programı tarafından ABD Jeoloji Araştırmaları Kurumu, Uluslararası Tropikal Tarım Merkezi, The Nature Conservancy ve Almanya'daki Kassel Üniversitesi Çevre Sistemleri Araştırma Merkezi iş ortaklığıyla geliştirilmiştir.
Bantlar
Piksel Boyutu 927,67 metre
Bantlar
Ad
Min.
Maks.
Piksel Boyutu
Açıklama
b1
0*
255*
metre
Drenaj yönü için olası değerler: 1=E, 2=SE, 4=S,
8=SW, 16=W, 32=NW, 64=N, 128=NE; okyanusa giden son çıkış hücreleri
0 değeriyle, endoreik havzanın (iç kısımda kalan çöküntü) en düşük noktasını işaretleyen hücreler ise
255 değeriyle (orijinal değer -1) işaretlenir.
* tahmini minimum veya maksimum değer
Kullanım Şartları
Kullanım Şartları
HydroSHEDS verileri, ticari olmayan ve ticari kullanım için ücretsizdir. Daha fazla bilgi için lütfen Lisans Sözleşmesi'ni inceleyin.
Alıntılar
Alıntılar:
Lehner, B., Verdin, K., Jarvis, A. (2008): New global hydrography
derived from spaceborne elevation data. Eos, Transactions, AGU,
89(10): 93-94.
HydroSHEDS, bölgesel ve küresel ölçekli uygulamalar için tutarlı bir biçimde hidrografik bilgiler sağlayan bir harita çıkarma ürünüdür. Nehir ağları, su havzası sınırları, drenaj yönleri ve akış birikimleri dahil olmak üzere çeşitli ölçeklerde coğrafi referanslı veri kümeleri (vektör ve raster) sunar. HydroSHEDS, 2000 yılında elde edilen yükseklik verilerine dayanmaktadır.
[null,null,[],[[["\u003cp\u003eHydroSHEDS provides hydrographic information like river networks and watershed boundaries at various scales, using a conditioned DEM based on SRTM elevation data.\u003c/p\u003e\n"],["\u003cp\u003eThis dataset depicts drainage direction using values 1-128, representing flow direction to the steepest downslope neighbor, with 0 indicating ocean outlets and 255 (originally -1) marking endorheic basins.\u003c/p\u003e\n"],["\u003cp\u003eOffered at a 30 arc-second resolution (approximately 927 meters), it is freely available for both commercial and non-commercial use under the specified license.\u003c/p\u003e\n"],["\u003cp\u003eData quality is reduced above 60 degrees northern latitude due to the reliance on coarser-resolution DEM in the absence of SRTM data for those regions.\u003c/p\u003e\n"],["\u003cp\u003eDeveloped by WWF in partnership with USGS and other organizations, it is ideal for applications needing consistent and comprehensive hydrographic data.\u003c/p\u003e\n"]]],["The HydroSHEDS dataset, provided by WWF, offers hydrographic data, including drainage direction, based on 2000 SRTM elevation data. It defines flow direction from each cell to its steepest downslope neighbor, using values from 1 to 128, with 0 indicating ocean outlets and -1 inland sinks. This dataset, available at 30 arc-second resolution (927.67 meters per pixel), is freely available for both commercial and non-commercial use and can be accessed via Google Earth Engine.\n"],null,["# WWF HydroSHEDS Drainage Direction, 30 Arc-Seconds\n\nDataset Availability\n: 2000-02-11T00:00:00Z--2000-02-22T00:00:00Z\n\nDataset Provider\n:\n\n\n [WWF](https://www.hydrosheds.org/)\n\nTags\n:\n[direction](/earth-engine/datasets/tags/direction) [drainage](/earth-engine/datasets/tags/drainage) [flow](/earth-engine/datasets/tags/flow) [geophysical](/earth-engine/datasets/tags/geophysical) [hydrography](/earth-engine/datasets/tags/hydrography) [hydrology](/earth-engine/datasets/tags/hydrology) [hydrosheds](/earth-engine/datasets/tags/hydrosheds) [srtm](/earth-engine/datasets/tags/srtm) [surface-ground-water](/earth-engine/datasets/tags/surface-ground-water) [water](/earth-engine/datasets/tags/water) [wwf](/earth-engine/datasets/tags/wwf) \n\n#### Description\n\nHydroSHEDS is a mapping product that provides hydrographic\ninformation for regional and global-scale applications in a consistent\nformat. It offers a suite of geo-referenced datasets (vector and\nraster) at various scales, including river networks, watershed\nboundaries, drainage directions, and flow accumulations. HydroSHEDS\nis based on elevation data obtained in 2000 by NASA's Shuttle Radar\nTopography Mission (SRTM).\n\nThis drainage direction dataset defines the direction\nof flow from each cell in the conditioned DEM to its steepest\ndown-slope neighbor. Values of drainage direction vary from 1\nto 128. All final outlet cells to the ocean are flagged with\na value of 0. All cells that mark the lowest point of an endorheic\nbasin (inland sink) are flagged with a value of -1. The drainage\ndirection values follow the convention adopted by ESRI's flow\ndirection implementation: 1=E, 2=SE, 4=S, 8=SW, 16=W, 32=NW,\n64=N, 128=NE. \n\n\u003cbr /\u003e\n\n\nThis dataset is at 30 arc-second resolution.\nThe datasets available at 30 arc-seconds are the Hydrologically\nConditioned DEM, Drainage (Flow) Direction, and Flow Accumulation.\n\nNote that the quality of the HydroSHEDS data is significantly lower for regions above\n60 degrees northern latitude as there is no underlying SRTM elevation data available\nand thus a coarser-resolution DEM was (HYDRO1k provided by USGS).\n\nHydroSHEDS was developed by the World Wildlife Fund (WWF)\nConservation Science Program in partnership with the U.S. Geological\nSurvey, the International Centre for Tropical Agriculture, The\nNature Conservancy, and the Center for Environmental Systems Research\nof the University of Kassel, Germany.\n\n### Bands\n\n\n**Pixel Size**\n\n927.67 meters\n\n**Bands**\n\n| Name | Min | Max | Pixel Size | Description |\n|------|-----|-------|------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| `b1` | 0\\* | 255\\* | meters | Drainage direction possible values: 1=E, 2=SE, 4=S, 8=SW, 16=W, 32=NW, 64=N, 128=NE; final outlet cells to the ocean are flagged with a value of 0 and cells that mark the lowest point of an endorheic basin (inland sink) are flagged with a value of 255 (original value of -1) |\n\n\\* estimated min or max value\n\n### Terms of Use\n\n**Terms of Use**\n\nHydroSHEDS data are free for non-commercial and commercial\nuse. For more information, please refer to the [License Agreement](https://www.hydrosheds.org/page/license).\n\n### Citations\n\nCitations:\n\n- Lehner, B., Verdin, K., Jarvis, A. (2008): New global hydrography\n derived from spaceborne elevation data. Eos, Transactions, AGU,\n 89(10): 93-94.\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('WWF/HydroSHEDS/30DIR');\nvar drainageDirection = dataset.select('b1');\nvar drainageDirectionVis = {\n min: 1.0,\n max: 128.0,\n palette: [\n '000000', '023858', '006837', '1a9850', '66bd63', 'a6d96a', 'd9ef8b',\n 'ffffbf', 'fee08b', 'fdae61', 'f46d43', 'd73027'\n ],\n};\nMap.setCenter(-121.652, 38.022, 8);\nMap.addLayer(drainageDirection, drainageDirectionVis, 'Drainage Direction');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/WWF/WWF_HydroSHEDS_30DIR) \n[WWF HydroSHEDS Drainage Direction, 30 Arc-Seconds](/earth-engine/datasets/catalog/WWF_HydroSHEDS_30DIR) \nHydroSHEDS is a mapping product that provides hydrographic information for regional and global-scale applications in a consistent format. It offers a suite of geo-referenced datasets (vector and raster) at various scales, including river networks, watershed boundaries, drainage directions, and flow accumulations. HydroSHEDS is based on elevation data obtained in 2000 ... \nWWF/HydroSHEDS/30DIR, direction,drainage,flow,geophysical,hydrography,hydrology,hydrosheds,srtm,surface-ground-water,water,wwf \n2000-02-11T00:00:00Z/2000-02-22T00:00:00Z \n-67.3 -180 62 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [](https://doi.org/https://www.hydrosheds.org/)\n- [](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/WWF_HydroSHEDS_30DIR)"]]
