What is topography data?
Topographic data describes the three-dimensional characteristics of the Earth’s surface, including elevation, slope, terrain features, vegetation height, and human-made structures.
How we use it
In our case, we are primarily interested in ground elevation both without and with above-ground features: the bare-earth elevation (Terrain Model) and the elevation including buildings and vegetation (Surface Model).
Our sources
We use Digital Elevation Models (DEMs) derived either from LiDAR point clouds or from satellite-based data, depending on data quality and coverage in the area where we train our model.
DEM1 refers to Digital Elevation Models with 1-meter spatial resolution. These datasets are generated from airborne LiDAR surveys and processed into gridded raster products, providing both Terrain Models (bare earth) and Surface Models (including buildings and vegetation).
DEM10/30 datasets are primarily derived from satellite based radar interferometry. Because radar signals reflect from the uppermost surfaces, these datasets represent Digital Surface Models (DSM) rather than bare-earth terrain.