As a Public Authority, the UKHO makes relevant data sets available in compliance with the ‘Infrastructure for Spatial Information in Europe’ (INSPIRE) initiative.
We have been accredited by the Marine Environmental Data and Information Network (MEDIN) as the national Data Archive Centre for bathymetric surveys. We have therefore included access to relevant bathymetric surveys held in our Data Archive Centre as part of our INSPIRE portal.
Currently the following data sets which are held by the UKHO are within the scope of the Directive:
- Limits around the UK as maintained by the UKHO’s ‘Law of the Sea’ department.
- Ships’ Routeing Measures as approved by the International Maritime Organisation (IMO), and/or the Maritime and Coastguard Agency (MCA) (as National Competent Authority).
- Bathymetric surveys from various sources, including a large number funded by the MCA, an executive agency sponsored by the Department for Transport, under the Civil Hydrography Programme
The data sets are available under the Open Government Licence. The terms of the Licence can be accessed here
- The data sets are not suitable for use in marine navigation or in the creation of navigational products.
- If you reuse any of the data, you must acknowledge the source by including the following attribution statement: “Contains public sector information, licensed under the Open Government Licence v3.0, from [the Owner/Originator of the data as indicated in the metadata]”.
Bathymetric Surveys - File Formats
- High density gridded data on the portal is available for download in a variety of formats:-
- tiff – a geo-referenced tiff image of the data. This can be easily displayed in all GIS systems to give an accurate representation of data coverage. A visual representation of comparative depths within the dataset is given by the colour range of the image, and individual depth values can be interrogated, but the data cannot be manipulated in any way. Tiff files are limited in size to 4Gb. Any files larger than 4Gb will automatically download as a ‘BigTiff’, which has similar functionality, provided the user’s software supports the format. If downloaded tiff files are larger than 4Gb, please check whether your software is compatible with BigTiff.
- BAG – a generic surface format which can be viewed in a wide range of GIS systems. Gives a visual representation of depths by colour range, and allows interrogation of individual depths, and manipulation to create required outputs. If your software does not support the BAG format, it may be helpful to view examples of the format using CARIS Easy View, which is available as a free download from Caris
- image/png – a standard image file suitable for high-resolution or print-quality reproduction.
- image/jpeg – a standard image file suitable for on-screen use.
- csv– a point by point listing of all depths in ‘Latitude; Longitude; Depth’ format. These files can be widely used in GIS systems to create a range of outputs. However, high-resolution datasets contain millions of data points, and the csv file produced may be too large for many systems to deal with. They may also be problematic to download, and in some cases will fail due to the time required to transfer such high volumes of data. We would therefore recommend use of BAG or BigTiff files for larger datasets.
- Please note that ungridded datasets are available only as .csv. These are all lower density data, and will produce files of a manageable size, which will download without difficulty.
- The viewer allows you to discover which individual data sets are available, preview them, and download the data itself. Use the drop-down menu in the ‘Themes’ box to select the data sets you wish to access and download.
- A link within the viewer is available to provide help on its use. Note that the section on logging in is not relevant.
- When a data set has been selected, a box will appear at the bottom of the screen displaying associated metadata. In the case of the surveys, three of the field names are not very intuitive. Specifically: “OBJNAM”=Title; “SUREND”=Survey end date; “hcosys”=Horizontal coordinate system
- The following browsers are currently supported: Google Chrome™, Windows® Internet Explorer 9, Windows® Internet Explorer 10, Mozilla Firefox
- Some INSPIRE data specifications are still in draft, so the formats may change in future.
- Some multi-beam surveys are archived at varying resolutions according to depth range. Where this is the case (eg, where 2m, 4m and 8m surfaces are available for a single survey) it will be necessary to download each surface as a separate file in order to obtain the full dataset.
- The base map for land areas is Open Street Map. The UKHO is not responsible for the content of this data. For example, the Territorial Sea limit shown on the base map differs from the downloadable UKHO version, which correctly takes into account relevant offshore features.
- The bathymetric surveys are observational data sets. A deconflicted, ‘best picture’ Digital Elevation Model of the seabed around the UK is not available here but can be obtained from UKHO licensees.
Published: 29 August 2014
From: UK Hydrographic Office