hydrografiska

Hydrografiska, commonly translated as hydrography, is the science and practice of measuring and describing the physical features of bodies of water and their surrounding environments. It covers oceans, seas, rivers, lakes, and coastal zones, and includes depth (bathymetry), seabed topography, shoreline configuration, tides, and currents. In a broader sense, it may also document salinity and water quality data when relevant to navigation and coastal management. The primary outputs are navigational products such as nautical charts and digital bathymetric models, but hydrography also supports coastal planning, flood risk assessment, offshore development, and environmental monitoring.

Survey methods combine acoustical, optical, and geodetic techniques. Bathymetric mapping uses single‑beam and multibeam echosounders, sub-bottom profiling, and, in shallow waters, LiDAR. Remote sensing from aircraft and satellites complements shipborne surveys. Tide gauges, current meters, and fixed reference stations provide temporal data, while geodetic control ensures consistent positioning for charts and databases.

Hydrographic information is essential for safe navigation, port and harbor operations, and the design and maintenance of offshore structures. It also informs maritime safety, search and rescue, and climate-related studies such as sea-level rise and coastal erosion. National hydrographic offices and institutes maintain data and respond to surveying requests from the shipping industry, coastal authorities, and researchers.

Standards and coordination are overseen internationally by the International Hydrographic Organization (IHO). Many countries publish official nautical charts and electronic navigational charts, following IHO specifications (for example S-57 and the newer S-101 standard for ENC data).