This Digital Elevation Model (DEM) is constructed from a combination of ASTER and SPOT-5 DEM's for the ice sheet periphery and margin (i.e. below the equilbrium line elevation) south of approximately 82.5°N, and AVHRR photoclinometry in the ice sheet interior and far north (Scambos and Haran, 2002).
SPOT-5 DEM's were produced and distributed as part of the Spot5 stereoscopic survey of Polar Ice: Reference Images & Topographies (SPIRIT) project (Korona et al., 2009). Ocean surfaces were masked using the GIMP Land Classification mask and replased with the CNES CLS11 mean sea surface height (Schaeffer et al., 2012).
Note
- All land elevation data is horizontally and vertically registered to average ICESat elevations for the 2003-2009 time period, and therefore the DEM has a nominal date of 2007, although care must be taken when using the DEM in areas of rapid change, such as major outlet glaciers south of 70°N.
- The DEM has a resolution of 30 m, although the "true" resolution of the DEM will vary from 40 m in areas of SPOT-5 coverage (see Korona et al. 2009) to 500 m in areas of photoclinometry.
- The ice-sheet-wide root-mean-squared validation error relative to ICESat is +/-10 m, rangining from close to +/- 1 m over most ice surfaces to +/- 30 m in areas of high relief.
该数字高程模型 (DEM) 由 ASTER 和 SPOT-5 DEM 的组合构建而成,用于冰盖外围和边缘(即平衡线高程以下)以南约 82.5°N,以及冰盖内部和远北(Scambos 和 Haran,2002 年)。
SPOT-5 DEM 是作为极地冰的 Spot5 立体测量:参考图像和地形 (SPIRIT) 项目(Korona 等人,2009 年)的一部分制作和分发的。海洋表面使用 GIMP 陆地分类掩码进行掩蔽,并使用 CNES CLS11 平均海面高度进行替换(Schaeffer 等人,2012 年)。
笔记
2003-2009 年期间,所有土地高程数据都被水平和垂直注册到平均 ICESat 高程,因此 DEM 的名义日期为 2007 年,但在快速变化的地区使用 DEM 时必须小心,例如主要70°N 以南的出口冰川。
DEM 的分辨率为 30 m,尽管 DEM 的“真实”分辨率将在 SPOT-5 覆盖区域(见 Korona 等人,2009)的 40 m 到光度测量区域的 500 m 之间变化。
相对于 ICESat 的冰盖范围均方根验证误差为 +/-10 m,范围从大多数冰面的接近 +/- 1 m 到高起伏区域的 +/- 30 m。
一般文件
Dataset Availability
1999-06-30T00:00:00 - 2002-09-04T00:00:00
Dataset Provider
Collection Snippet
ee.Image("OSU/GIMP/DEM")
Bands Table
Name | Description | Resolution | Units |
elevation | Elevation | 30 meters | Meters |
数据引用:
Howat, I.M., A. Negrete, B.E. Smith, 2014, The Greenland Ice Mapping Project (GIMP) land classification and surface elevation datasets, The Cryosphere, 8, 1509-1518, doi:10.5194/tc-8-1509-2014article pdf
代码:
var dataset = ee.Image('OSU/GIMP/DEM'); var elevation = dataset.select('elevation'); var elevationVis = { min: 0.0, max: 2000.0, }; Map.setCenter(-41.0, 76.0, 4); Map.addLayer(elevation, elevationVis, 'Elevation');