A Digital Elevation Model (DEM) is a digital representation of the elevation of the earth’s surface. DEM data is derived from a wide variety of sources including image stereopairs, digitized paper topographic maps, radar interferometry, and laser scanning technology.
i-cubed has been working closely with the creation and usage of DEMs – in 1999, we were the first organization to produce a complete seamless mosaic of the individual USGS 7.5-minute DEMs. Our work on this project led us to pioneer new techniques in edgematching, artifact removal, and interpolation. The final product, known as eDEM, has been used by multitudes of customers—large and small—for planning, modeling, simulation, and visualization.
We have been actively compiling and reselling NED (National Elevation Dataset – the USGS seamless elevation mosaic) in addition to eDEM. We offer a 30-meter version of eDEM and NED over the conterminous US, Hawaii and Puerto Rico. In addition, a 10-meter version of eDEM and NED is available over the entire conterminous US and Hawaii. Over Alaska, a 2-arc-second (approx. 60-meter) version of NED is available.
Outside the United States, we have several offerings with high levels of coverage and detail:
- A seamless mosaic of Canadian elevation data at 90m, with coverage over southern and western Canada
- A seamless mosaic of Mexican elevation data at 90m, covering the entire country
- ASTER GDEM 1 arc-second (~30m) for all major land areas of the world
- SRTM 3 arc-second (~90m) for global areas between 60° North and South
- GTOPO30 30 arc-second (~1km) for the entire world
- SRTM30 30 arc-second (~1km) for the entire world
High-resolution datasets over various parts of the world are available with our Intermap NEXTMap data. This high-resolution, high-quality, globally-consistent dataset is produced from a proprietary radar interferometry process. Each NEXTMap area can be ordered with any combination of a 5-meter digital surface model, a 5-meter digital terrain model, and a 2.5m, 1.25m, or 0.625m orthorectified image. NEXTMap data is available over the US (including parts of Alaska), Puerto Rico, Jamaica, western Europe, Malaysia, Indonesia, parts of Australia, and parts of Melanesia.
If your area of interest is not currently in our archive, or the resolution of our available data is not suitable for your purposes, we can create a new dataset for you. There are many sources of custom elevation data and many methods for creating new data we are familiar with. We work with our customers to ensure their needs for elevation data are met without unnecessary expense.
Do you have elevation data that needs to be converted into a more useful format? We can do that! LIDAR point clouds, for example, are very useful but difficult to work with. We can convert point cloud data in LAS or other formats to a set of standard raster digital elevation models, one representing bald earth (digital terrain model) and one representing canopy height (digital surface model). We can also convert vector data such as contours and spot heights to raster DEMs, or vice versa.
Do you have your own high-resolution terrain data that you need to access more conveniently? Through DataDoors, we host your custom datasets and offer them back to you with a convenient and intuitive user interface. With DataDoors, it’s easy to define an area of interest, output format, projection and delivery mechanism. DataDoors can also easily generate derivative products, such as hillshades, slope, aspect, curvature, contours and canopy height. We can also stream your elevation data through DataDoors’ WCS mechanism, or render it as a static hillshade or pseudocolor image through WMS.