Accurate bathymetry is the foundation for much of ocean science and policy

A bathymetric map of Lake Huron

A bathymetric image of Lake Huron. In the same way that topographic maps represent the three-dimensional features (or relief) of overland terrain, bathymetric maps illustrate the land that lies underwater.

Bathymetric data, which includes information about the depths and shapes of underwater terrain, has a range of uses:

  • Nautical charts are based on data acquired during bathymetric surveys. These charts guide mariners much as road maps guide motorists, ensuring safe and efficient maritime transportation.
  • Bathymetric maps are increasingly important as scientists learn more about the effects of climate change on the environment. Bathymetric surveys can alert scientists to ongoing and potential beach erosion, sea-level rise, and subsidence (land sinking). Scientists also use bathymetric data to create hydrodynamic models.
  • Bathymetry is a key element of biological oceanography. The depth and characteristics of the seabed define the habitat for benthic (bottom-dwelling) organisms, and are fundamental parameters of marine ecosystems. Scientists use high-resolution bathymetry to help determine where fish and other sea life will feed, live, and breed.

For more information:

Office of Coast Survey

National Geophysical Data Center, Bathymetry and Global Relief

Seafloor Mapping, NOS Education