In August 2008, the National Geophysical Data Center (NGDC), an office of the National Oceanic and Atmospheric Administration (NOAA), developed the ETOPO1 Global Relief Model as an improvement to the ETOPO2v2 Global Relief Model. ETOPO1 is available in "Ice Surface" (top of Antarctic and Greenland ice sheets) and "Bedrock" (base of the ice sheets) versions. Both versions of ETOPO1 were generated from diverse global and regional digital data sets, which were shifted to common horizontal and vertical datums, and then evaluated and edited as needed. Bathymetric, topographic, and shoreline data used in ETOPO1 were obtained from NGDC, Antarctic Digital Database (ADD), European Ice Sheet Modeling Initiative (EISMINT), Scientific Committee on Antarctic Research (SCAR), Japan Oceanographic Data Center (JODC), Caspian Environment Programme (CEP), Mediterranean Science Commission (CIESM), National Aeronautics and Space Administration (NASA), National Snow and Ice Data Center (NSIDC), Scripps Institute of Oceanography (SIO), and Leibniz Institute for Baltic Sea Research (LIBSR). ETOPO1 is vertically referenced to sea level, and horizontally referenced to the World Geodetic System of 1984 (WGS 84). Cell size for ETOPO1 is 1 arc-minute.

NASA's Physical Oceanography Distributed Active Archive Center (PO.DAAC) is located at NASA's Jet Propulsion Laboratory in Pasadena, California. PO.DAAC manages and provides tools and services for NASA's oceanographic and hydrologic data (satellite, airborne, and in-situ) to enable a greater understanding of the physical processes and conditions of the global ocean. Measurements include gravity, ocean winds, sea surface temperature, ocean surface topography, sea surface salinity, and circulation. The data support a wide range of applications including climate research, weather prediction, resource management, policy, and the stewardship of ocean data resources.

The EuroMapApp task of the AtlantOS project aims to integrate Europe’s existing and future bathymetric data sets from the Atlantic Ocean into a seamless whole and put these results into a widely accessible format allowing immediate visualization of the seafloor for the specialist and non-specialist user alike. The partner institutions are GEOMAR, Ifremer, NIOZ, and NERC-BODC.

The EMODnet Bathymetry portal is operated and further developed by a European partnership. This comprises members of the SeaDataNet consortium together with organisations from marine science, the hydrographic survey community, and industry. The partners combine expertises and experiences of collecting, processing, and managing of bathymetric data together with expertises in distributed data infrastructure development and operation and providing OGC services (WMS, WFS, and WCS) for viewing and distribution. SeaDataNet is a leading infrastructure in Europe for marine & ocean data management, initiated and managed by the National Oceanographic Data Centres (NODC's). It is actively operating and further developing a Pan-European infrastructure for managing, indexing and providing access to ocean and marine data sets and data products, acquired via research cruises and other in-situ observational activities. The basis of SeaDataNet is interconnecting Data Centres into a distributed network of data resources with common standards for metadata, vocabularies, data transport formats, quality control methods and flags, and access. SeaDataNet is aiming for an extensive coverage of available data sets for the various marine environmental disciplines, such as physical oceanography, marine chemistry, biology, biodiversity, geology, geophysics and bathymetry. This is implemented by seeking active cooperation at a national scale with institutes and at a European scale with communities, that are engaged in data management for these disciplines, and by seeking opportunities for including their data centres and data collections in the SeaDataNet metadata and data provision.

The GEBCO_2022 Grid is a global continuous terrain model for ocean and land with a spatial resolution of 15 arc seconds. In regions outside of the Arctic Ocean area, the grid uses as a base Version 2.4 of the SRTM15_plus data set (Tozer, B. et al, 2019). This data set is a fusion of land topography with measured and estimated seafloor topography. Included on top of this base grid are gridded bathymetric data sets developed by the four Regional Centers of The Nippon Foundation-GEBCO Seabed 2030 Project. The GEBCO_2022 Grid represents all data within the 2022 compilation. The compilation of the GEBCO_2022 Grid was carried out at the Seabed 2030 Global Center, hosted at the National Oceanography Centre, UK, with the aim of producing a seamless global terrain model. Outside of Polar regions, the Regional Centers provide their data sets as sparse grids i.e. only grid cells that contain data are populated. These data sets were included on to the base using a remove-restore blending procedure. This is a two-stage process of computing the difference between the new data and the base grid and then gridding the difference and adding the difference back to the existing base grid. The aim is to achieve a smooth transition between the new and base data sets with the minimum of perturbation of the existing base data set. The data sets supplied in the form of complete grids (primarily areas north of 60N and south of 50S) were included using feather blending techniques from GlobalMapper software. The GEBCO_2022 Grid has been developed through the Nippon Foundation-GEBCO Seabed 2030 Project. This is a collaborative project between the Nippon Foundation of Japan and the General Bathymetric Chart of the Oceans (GEBCO). It aims to bring together all available bathymetric data to produce the definitive map of the world ocean floor by 2030 and make it available to all. Funded by the Nippon Foundation, the four Seabed 2030 Regional Centers include the Southern Ocean - hosted at the Alfred Wegener Institute, Germany; South and West Pacific Ocean - hosted at the National Institute of Water and Atmospheric Research, New Zealand; Atlantic and Indian Oceans - hosted at the Lamont-Doherty Earth Observatory, Columbia University, USA; Arctic and North Pacific Oceans - hosted at Stockholm University, Sweden and the Center for Coastal and Ocean Mapping at the University of New Hampshire, USA.

The GEBCO_2020 Grid was released in May 2020 and is the second global bathymetric product released by the General Bathymetric Chart of the Oceans (GEBCO) and has been developed through the Nippon Foundation-GEBCO Seabed 2030 Project. The GEBCO_2020 Grid provides global coverage of elevation data in meters on a 15 arc-second grid of 43200 rows x 86400 columns, giving 3,732,480,000 data points. Grid Development The GEBCO_2020 Grid is a continuous, global terrain model for ocean and land with a spatial resolution of 15 arc seconds. The grid uses as a ‘base’ Version 2 of the SRTM15+ data set (Tozer et al, 2019). This data set is a fusion of land topography with measured and estimated seafloor topography. It is augmented with the gridded bathymetric data sets developed by the four Seabed 2030 Regional Centers. The Regional Centers have compiled gridded bathymetric data sets, largely based on multibeam data, for their areas of responsibility. These regional grids were then provided to the Global Center. For areas outside of the polar regions (primarily south of 60°N and north of 50°S), these data sets are in the form of 'sparse grids', i.e. only grid cells that contain data were populated. For the polar regions, complete grids were provided due to the complexities of incorporating data held in polar coordinates. The compilation of the GEBCO_2020 Grid from these regional data grids was carried out at the Global Center, with the aim of producing a seamless global terrain model. In contrast to the development of the previous GEBCO grid, GEBCO_2019, the data sets provided as sparse grids by the Regional Centers were included on to the base grid without any blending, i.e. grid cells in the base grid were replaced with data from the sparse grids. This was with aim of avoiding creating edge effects, 'ridges and ripples', at the boundaries between the sparse grids and base grid during the blending process used previously. In addition, this allows a clear identification of the data source within the grid, with no cells being 'blended' values. Routines from Generic Mapping Tools (GMT) system were used to do the merging of the data sets. For the polar data sets, and the adjoining North Sea area, supplied in the form of complete grids these data sets were included using feather blending techniques from GlobalMapper software version 11.0, made available by Blue Marble Geographic. The GEBCO_2020 Grid includes data sets from a number of international and national data repositories and regional mapping initiatives. For information on the data sets included in the GEBCO_2020 Grid, please see the list of contributions included in this release of the grid (https://www.gebco.net/data_and_products/gridded_bathymetry_data/gebco_2020/#compilations).