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  2. List of GIS data sources - Wikipedia

    en.wikipedia.org/wiki/List_of_GIS_data_sources

    Global Roads Open Access Data Set (gROADS) Well documented global dataset from NASA's Socioeconomic Data and Applications Center of roads between settlements using a consistent data model (UNSDI-T v.2) which is, to the extent possible, topologically integrated, and accurate to approximately 50m. Only roads between settlements are included, not ...

  3. DTED - Wikipedia

    en.wikipedia.org/wiki/DTED

    DTED (or Digital Terrain Elevation Data) is a standard of digital datasets which consists of a matrix of terrain elevation values, i.e., a Digital Elevation Model.This standard was originally developed in the 1970s to support aircraft radar simulation and prediction.

  4. GIS file format - Wikipedia

    en.wikipedia.org/wiki/GIS_file_format

    USGS DEM – The USGS' Digital Elevation Model GTOPO30 – Large complete Earth elevation model at 30 arc seconds, delivered in the USGS DEM format; DTED – National Geospatial-Intelligence Agency (NGA)'s Digital Terrain Elevation Data, the military standard for elevation data; World file – Georeferencing a raster image file (e.g. JPEG, BMP)

  5. Generic Mapping Tools - Wikipedia

    en.wikipedia.org/wiki/Generic_Mapping_Tools

    The software stores 2-D grids as COARDS-compliant netCDF files and comes with a comprehensive collection of free GIS data, such as coast lines, rivers, political borders and coordinates of other geographic objects. Users convert further data (like satellite imagery and digital elevation models) from other sources and

  6. National Elevation Dataset - Wikipedia

    en.wikipedia.org/wiki/National_Elevation_Dataset

    The National Elevation Dataset (NED) consists of high precision topography or ground surface elevation data (digital elevation model) for the United States. It was maintained by the USGS and all the data is in the public domain. Since the 3D Elevation Program came online, the NED was subsumed [1] into The National Map as one of its layers of ...

  7. List of free geology software - Wikipedia

    en.wikipedia.org/wiki/List_of_free_geology_software

    This is a list of free and open-source software for geological data handling and interpretation. The list is split into broad categories, depending on the intended use of the software and its scope of functionality. Notice that 'free and open-source' requires that the source code is available and users are given a free software license.

  8. Digital elevation model - Wikipedia

    en.wikipedia.org/wiki/Digital_elevation_model

    Submarine elevation (known as bathymetry) data is generated using ship-mounted depth soundings. When land topography and bathymetry is combined, a truly global relief model is obtained. The SRTM30Plus dataset (used in NASA World Wind) attempts to combine GTOPO30, SRTM and bathymetric data to produce a truly global elevation model. [32]

  9. National lidar dataset - Wikipedia

    en.wikipedia.org/wiki/National_lidar_dataset

    A national lidar dataset refers to a high-resolution lidar dataset comprising most—and ideally all—of a nation's terrain. Datasets of this type typically meet specified quality standards and are publicly available for free (or at nominal cost) in one or more uniform formats from government or academic sources.