korkeusdatoihin

korkeusdata refers to the set of numerical and descriptive information that represents the vertical position of geographic features above a reference level, usually mean sea level. The term is most widely used in geographic information system (GIS) and surveying contexts where precise elevation values are required for mapping, engineering, or environmental analysis. Elevation data can be obtained through various methods, including ground-based surveying with GNSS receivers, photogrammetric analysis of aerial imagery, radar altimetry, satellite-derived digital elevation models (DEMs), and airborne LiDAR scanning. Each source offers different spatial resolution, accuracy, and coverage; for example, LiDAR typically delivers sub-meter precision at point densities exceeding 10 points per square meter, while satellite DEMs such as SRTM provide one arc-second (~30 m) resolution worldwide.

In many countries the collection, storage and dissemination of korkeusdata are governed by national agencies that maintain standardized data formats (e.g., GeoTIFF, Shapefile) and coordinate reference systems. In Finland, for instance, the National Land Survey provides high-resolution elevation layers that are used for hydrological modelling, floodplain mapping, and infrastructure planning. Accuracy metrics such as vertical root mean square error (VRMSE) and systematic bias are routinely reported so that end users can assess suitability for specific tasks. Integration of korkeusdata with other cartographic layers allows creation of slope, aspect, and prominence maps, which are essential tools for forestry management, urban growth analysis, and recreational route design.