ETOPO1 is a 1 arc-minute global relief model of Earth's surface that integrates land topography and ocean bathymetry. It was built from numerous global and regional data sets. This is the 'Ice Surface' version, with the top of the Antarctic and Greenland ice sheets. The horizontal datum is WGS-84, the vertical datum is Mean Sea Level. Keywords: Bathymetry, Digital Elevation. This is the grid/node-registered version: the dataset's latitude and longitude values mark the centers of the cells.

The General Bathymetric Chart of the Oceans (GEBCO) consists of an international group of experts who work on the development of a range of bathymetric data sets and products. GEBCO operates under the joint auspices of the International Hydrographic Organization (IHO) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO. See our web site for more information about GEBCO at http://www.gebco.net/. The layer included in this WMS are based on the GEBCO_2014 Grid. The data set was originally published in 2014, last updated in April 2015. Please note the data set has now been superseded by a later version. Further information about GEBCO's products can be found on GEBCO's web site: www.gebco.net. The bathymetric portion of the GEBCO_2014 Grid was largely generated from a database of ship-track soundings with interpolation between soundings guided by satellite-derived gravity data. However, in areas where they improve on the existing GEBCO Grid, data sets generated by other methods have been included. Further information about the data sets included in the grid can be found in the documentation that accompanies the data set and is available from https://www.gebco.net/data_and_products/historical_data_sets/#gebco_2014. Within the GEBCO_2014 Grid, the area south of 60S is based on the International Bathymetric Chart of the Southern Ocean (IBCSO) v1 www.ibcso.org. The imagery for land areas in this WMS, north of 60 degrees south, is largely taken from the NASA Blue Marble: Next Generation data set, produced by Reto Stockli, NASA Earth Observatory, the NASA Goddard Space Flight Center (http://earthobservatory.nasa.gov/Features/BlueMarble). For land areas south of 60 degrees south, coastline and ice shelf information is taken from the Scientific Committee on Antarctic Research (SCAR) Antarctic Digital Database coastline dataset (www.add.scar.org/Information). Details on how to download the GEBCO Grid can be found at https://www.gebco.net/data_and_products/gridded_bathymetry_data/. This WMS delivers imagery in a polar view centred on the South Pole. Separate WMS's provided global imagery for the GEBCO Grid and imagery centred on the North Pole. Please note that the GEBCO Grid is mainly a deeper water data set and does not contain detailed bathymetry in shallower water areas. This WMS has been developed by the British Oceanographic Data Centre (BODC) on behalf of the GEBCO community. If imagery from this WMS is included in web sites, reports and digital and printed imagery then we request that the source of the dataset is acknowledged and be of the form 'Imagery reproduced from the GEBCO Grid, version xxxxxx, www.gebco.net'. Where 'version xxxxxx' is the appropriate version number of the GEBCO Grid, given in the layer information below. Also included in this WMS is a layer based on the GEBCO_08, Grid gebco_08_grid_south_polar_view.

The General Bathymetric Chart of the Oceans (GEBCO) consists of an international group of experts who work on the development of a range of bathymetric data sets and products. GEBCO operates under the joint auspices of the International Hydrographic Organization (IHO) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO. See our web site for more information about GEBCO at www.gebco.net. This WMS provides access to the GEBCO_2014, in the form of shaded relief imagery as layer 'GEBCO_NORTH_POLAR_VIEW' in a polar stereographic projection for the region north of 50N. The GEBCO_2014 Grid is a global grid of elevation data at 30 arc-second intervals. Please note that this data set has now been superseded by a later GEBCO grid. Please visit GEBCO's web site for further details: www.gebco.net. The bathymetric portion of the grid was largely generated from a database of ship-track soundings with interpolation between soundings guided by satellite-derived gravity data. However, in areas where they improve on the existing GEBCO Grid, data sets generated by other methods have been included. Further information about the data sets included in the grid can be found in the documentation that accompanies the data set and is available from www.gebco.net/data_and_products/gridded_bathymetry_data/gebco_30_second_grid/. For the area north of 64N, the GEBCO_2014 Grid is based on the International Bathymetric Chart of the Arctic Ocean (IBCAO) v3 www.ibcao.org. Within the GEBCO grid land elevation data is largely taken from the 30 arc-second version of the Shuttle Radar Topography Mission data set (SRTM30). Further details can be found in the data set's documentation. Within the IBCAO, land areas are largely based on the Global Multi-resolution Terrain Elevation Data 2010 data set (GMTED2010). Over Greenland the approximately 2000 by 2000 m resolution Digital Elevation Model (DEM) published by Ekholm (1996) is used. Within the WMS, the outlines of glaciers (shown in white) are included from the GLIMS Database: GLIMS, and National Snow and Ice Data Center. 2005, updated 2012. GLIMS Glacier Database, Version 1. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. http://dx.doi.org/10.7265/N5V98602. The coverage of the Greenland Ice Sheet is shown in white and is based on data from the Atlas of the Cryosphere Northern Hemisphere (https://nsidc.org/data/atlas/). Information on how to download the GEBCO's grids can be found at www.gebco.net. This WMS delivers imagery in a polar view centred on the North Pole. Separate WMS's provided global imagery for the GEBCO Grid and imagery centred on the South Pole. Please note that GEBCO's grids are mainly deeper water data sets and do not contain detailed bathymetry in shallower water areas. This WMS has been developed by the British Oceanographic Data Centre (BODC) on behalf of the GEBCO community. If imagery from this WMS is included in web sites, reports and digital and printed imagery then we request that the source of the dataset is acknowledged and be of the form 'Imagery reproduced from the GEBCO Grid, version xxxxxx, www.gebco.net'. Where 'version xxxxxx' is the appropriate version number of the GEBCO Grid, given in the layer information below.

CHS offers 500-metre bathymetric gridded data for users interested in the topography of the seafloor. This data provides seafloor depth in metres and is accessible for download as predefined areas.

ETOPO1 is a 1 arc-minute global relief model of Earth's surface that integrates land topography and ocean bathymetry. It was built from numerous global and regional data sets. This is the 'Ice Surface' version, with the top of the Antarctic and Greenland ice sheets. The horizontal datum is WGS-84, the vertical datum is Mean Sea Level. Keywords: Bathymetry, Digital Elevation. This is the grid/node-registered version: the dataset's latitude and longitude values mark the centers of the cells.

ETOPO1 is a 1 arc-minute global relief model of Earth's surface that integrates land topography and ocean bathymetry. It was built from numerous global and regional data sets. This is the 'Ice Surface' version, with the top of the Antarctic and Greenland ice sheets. The horizontal datum is WGS-84, the vertical datum is Mean Sea Level. Keywords: Bathymetry, Digital Elevation. This is the grid/node-registered version: the dataset's latitude and longitude values mark the centers of the cells.

The General Bathymetric Chart of the Oceans (GEBCO) consists of an international group of experts who work on the development of a range of bathymetric data sets and products. GEBCO operates under the joint auspices of the International Hydrographic Organization (IHO) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO. See our web site for more information about GEBCO at https://www.gebco.net/. This service provides access to GEBCO's latest global bathymetric grid, GEBCO_2014, in the form of shaded relief imagery as layer 'GEBCO_LATEST'. It also provides access to imagery based on the Source Identifier (SID) Grid that accompanies the GEBCO_2014 Grid as GEBCO_LATEST_SID. The GEBCO_2014 Grid is a global grid of elevation data at 30 arc-second intervals. This data set is available as a Web Map Service (WMS) for use as imagery in your applications. The bathymetric portion of the grid was largely generated from a database of ship-track soundings with interpolation between soundings guided by satellite-derived gravity data. However, in areas where they improve on the existing GEBCO Grid, data sets generated by other methods have been included. Further information about the data sets included in the grid can be found in the documentation that accompanies the data set and is available from https://www.gebco.net/data_and_products/gridded_bathymetry_data/ Within the GEBCO grid land elevation data is largely taken from the 30 arc-second version of the Shuttle Radar Topography Mission data set (SRTM30). Further details can be found in the data set's documentation. The imagery for land areas in this WMS, north of 60 degrees south, is largely taken from the NASA Blue Marble: Next Generation data set, produced by Reto Stockli, NASA Earth Observatory, the NASA Goddard Space Flight Center (http://earthobservatory.nasa.gov/Features/BlueMarble). For land areas south of 60 degrees south, coastline and ice shelf information is taken from the Scientific Committee on Antarctic Research (SCAR) Antarctic Digital Database coastline dataset (http://www.add.scar.org). The GEBCO global grid is accompanied by a Source Identifier (SID) grid - this indicates which of the corresponding cells in the GEBCO grid are based on soundings or existing grids and which are interpolated. The SID grid accompanying the GEBCO_2014 Grid is available as a layer in this WMS, GEBCO_LATEST_SID. GEBCO's first gloabl 30 arc-second interval terrain model was the GEBCO_08 Grid, published in January 2009. The WMS layer generated for the 2010 version of the GEBCO_08 Grid is included as a layer, 'GEBCO_08', within this WMS to accommodate users of this existing WMS layer. Information on how to download the GEBCO's grids can be found at https://www.gebco.net/ Please note that GEBCO's grids are mainly deeper water data sets and do not contain detailed bathymetry in shallower water areas. This WMS has been developed by the British Oceanographic Data Centre (BODC) on behalf of the GEBCO community. If imagery from this WMS is included in web sites, reports and digital and printed imagery then we request that the source of the dataset is acknowledged and be of the form 'Imagery reproduced from the GEBCO Grid, version xxxxxx, www.gebco.net'. Where 'version xxxxxx' is the appropriate version number of the GEBCO Grid, given in the layer information below.

**CHS NONNA data has been updated: May 29, 2024 ** The Canadian Hydrographic Service (CHS) offers a complete inventory of bathymetric data free to the general public for non-navigational use called 'CHS NONNA' for the 'NON-NAvigational' purpose of the data. The product is available in a spatial resolution of 10 metres or 100 metres. To directly access the CHS NONNA Data Portal please follow this link - https://data.chs-shc.ca/login (Note: The data portal is NOT compatible with Internet Explorer browser). Terms of Use The Canadian Hydrographic Service (CHS) NONNA Data products are for NON-NAVIGATIONAL USE ONLY. Please see the Open Data Licence below and the CHS NONNA LICENCE viewable on https://data.chs-shc.ca/login and downloadable with the NONNA data, for the full terms and conditions governing the use of this data. ----- PRODUCT DESCRIPTION ----- The CHS NONNA-10 NONNA-100 and NONNA Package Bathymetric Data products represent a consolidation of digital bathymetric sources managed by the CHS in Canadian jurisdiction. The « NONNA » refers to NON-NAvigational. The « 10 » or « 100 » references the approximate resolution (in metres) of the data. NONNA Packages A NONNA Package is a ZIP file containing a collection of NONNAP datasets to ease the download of large amounts of high resolution data. Packages are currently available for data sources of approximately 10 metre resolution. The «P10 » refers to the Packages and approximate resolution (in metres) of the data. The CHS NONNA-10 individual product coverage (resolution) is as follows: • South of 68°N the products = 0.1° latitude X 0.1° longitude (0.0001 degrees) • 68°N-80°N the products = 0.1° latitude X 0.2° longitude (0.0002 degrees) • 80°N and north the products = 0.1° latitude X 0.4° longitude (0.0004 degrees) The CHS NONNA-100 individual product coverage (resolution) is as follows: • South of 68°N the products = 1° latitude X 1° longitude (0.001 degrees) • 68°N-80°N the products = 1° latitude X 2° longitude (0.002 degrees) • 80°N and north the products = 1° latitude X 4° longitude (0.004 degrees) The CHS NONNA-P10 Packages are ZIP files that contain product coverage (resolution) defined as: • South of 68°N the products = 1° latitude X 1° longitude (0.0001 degrees) • 68°N-80°N the products = 1° latitude X 2° longitude (0.0002 degrees) • 80°N and north the products = 1° latitude X 4° longitude (0.0004 degrees) ----- DATUM ----- All CHS NONNA data sources are horizontally referenced to the World Geodetic System 1984 (WGS84) ESPG:4326 and vertically referenced to Chart Datum (CD), a tidal or water level datum that is locally derived and, of which, the depth of water should seldom fall below. For more information on vertical references visit: https://tides.gc.ca/tides/en/vertical-datum-chart-references ----- DATA PRESENTATION ----- CHS NONNA products adhere to the following naming convention: NONNAXXX_SouthwestCorner Example: NONNAP10_4360N07940W • NONNAP10 = the product NONNAP10 • 4360N07940W = the southwest corner of the NONNA cell. These products are available to view, query and download via the CHS NONNA Data Portal. The following formats are available for download: • 32-bit GeoTIFF • ASCII++ (XYZ) • CSAR • BAG These formats can be opened using various GIS applications. Alternatively, the CHS NONNA products can be accessed via Web Map Service (WMS), Web Coverage Service (WCS) or Web Map Tile Service (WMTS) links: WMS https://nonna-geoserver.data.chs-shc.ca/geoserver/wms?request=GetCapabilities WMTS https://nonna-geoserver.data.chs-shc.ca/geoserver/gwc/service/wmts?request=GetCapabilities WCS https://nonna-geoserver.data.chs-shc.ca/geoserver/wcs?request=GetCapabilities *Note* Gaps in the data may be visible where modern surveys have not yet been conducted, the data is not updated to Chart Datum (CD) or where legacy data has not yet been digitized. In addition, there may be data sources removed from the Data Portal for further processing in the CHS’ Bathymetric Database, and will not be available until such work is complete. Data sources included in the NONNA products may not have been subjected to the same level of quality assurance as those in official navigational products. *Help* New users of the CHS NONNA Data Portal are encouraged to fully review the 'CHS NONNA Data Portal Guidance Document' (PDF) which is available below in the RESOURCES section of this page.