GMRT brings together a variety of elevation sources which are delivered as multi-resolutional images and grids of land and ocean elevations. A mask layer is available that highlights the high-resolution data. We also keep track of cruises that we have reviewed but not included in the GMRT synthesis. Please contact us if you would like to contribute data.
Source data in GMRT v3.5 include:
- Ship-based multibeam swath bathymetry data (100-m resolution) from research cruises assessed, cleaned, processed and curated by the MGDS. The current version (GMRT v3.5) was released in February 2018 and includes swath data from 1007 cruises.
- Terrestrial elevation data (10-m resolution) for portions of the US from the USGS National Elevation Dataset (NED)
- Terrestrial elevation data (30-m resolution) from NASA’s Advanced Spaceborne Thermal Emission and Reflection Radiometer global DEM (ASTER)
- Gridded seafloor depth data (variety of scales) contributed by the international science community
- Gridded seafloor depth data (30 arc-second resolution) from the General Bathymetric Char t of the Oceans (GEBCO_2014)
- Gridded seafloor depth data (2-km resolution) from the International Bathymetric Chart of the A rctic Ocean (IBCAO) version 2.23
- Gridded seafloor depth data and ice surface data (500 m resolution) from the International Bathymetric Chart of the Southern Ocean (IBCSO)