The data set consists of digital bathymetric contours taken from the International Bathymetric Chart of the Mediterranean (IBCM) chart series. Most of the IBCM sheets depict contours at depths at 0m (coastline), 20m, 50m, 100m, and 200m, and at 200m intervals thereafter, although the actual contours displayed vary slightly from sheet to sheet. The data set is included in the GEBCO Digital Atlas (GDA). Through the GDA software interface the IBCM bathymetric contours can be exported in ASCII or shapefile format. The 10 sheets of the IBCM chart series are on a Mercator Projection at a scale of 1:1 million (at 38 N). The Black Sea is included at a scale of 1:2 million. The IBCM (1st Edition) chart series was published by the Head Department of Navigation and Oceanography of the USSR Ministry of Defence, St. Petersburg, under the auspices of the Intergovernmental Oceanographic Commission (IOC) of UNESCO 1981. The bathymetric contours and coastlines from the IBCM sheets were digitised. Error checking and quality control work on the data set was carried out at BODC. The digital data set was first made available in 1988.

Sea surface temperature and salinity data have been collected around British coastal waters and in the North Atlantic between 1963 and 1990. The data were collected by ships regularly plying routes between ports in the British Isles and the Continent, and along routes to the North Atlantic Ocean Weather Stations (OWS). Thirty individual shipping routes have been involved, approximately weekly measurements being taken at intervals ranging from 10 to 50 miles depending on the route. The following list details shipping routes and dates of data collection: Bristol - Finistere (Jan 1963 - Nov 1968); Clyde - OWS Alpha (May 1963 - Feb 1974); Clyde - OWS India (Jan 1963 - Jul 1975); Clyde - OWS Juliet (Jan 1963 - Jul 1975); Clyde - OWS Kilo (Mar 1963 - Dec 1972); Clyde - OWS Lima (Mar 1963 - May 1965, Jul 1975 - Dec 1990); Felixstowe - Rotterdam (Aug 1970 - Dec 1990); Fishguard - Cork (Jan 1963 - Oct 1968); Fishguard - Waterford (Jan 1963 - Dec 1966); Folkstone - Boulogne (Jan 1963 - Aug 1966); Heysham - Belfast (Feb 1965 - May 1977); Holyhead - Kish (Jan 1963 - Feb 1966); Hull - Kristiansand (Jan 1963 - May 1976); Larne - Stranraer (Jan 1963 - Feb 1966, Jan 1971 - Dec 1986); Leith - Bremen (Jan 1963 - Apr 1972); Leith - Copenhagen (Jan 1963 - Mar 1968); Liverpool - Belfast (Dec 1970 - Nov 1978); Liverpool - Douglas (Mar 1965 - Nov 1968); Liverpool - Dublin (Mar 1965 - Aug 1979); Liverpool - Larne (Jan 1987 - Dec 1988); Newhaven - Dieppe (Apr 1963 - Feb 1990); Scilly - Shamrock (May 1967 - Mar 1974); Southampton - Le Havre (Jan 1963 - May 1964); Southampton - St. Malo (May 1963 - Sep 1964); Swansea - Cork (May 1970 - Mar 1979); Weymouth - Channel Islands (Nov 1970 - Nov 1985); Weymouth - Cherbourg (Apr 1986 - Sep 1986); Whitehaven - Anglesey (Feb 1965 - Jan 1969). These observations provide useful information on the seasonal and short-term variability of temperature off-shore, and may enhance our knowledge regarding extreme values. The data were collected on behalf of the Ministry of Agriculture, Fisheries and Food, Lowestoft Fisheries Laboratory and are stored at the British Oceanographic Data Centre.

The General Bathymetric Chart of the Oceans (GEBCO) One Minute Grid is a global terrain model for land and sea at one arc-minute intervals. The grid is largely based on the bathymetric contours contained in the Centenary Edition of the GEBCO Digital Atlas, existing grids are used in some areas. The land areas are based on the Global Land One-km Base Elevation (GLOBE) Project data set. The grid was originally released in 2003 and updated in 2008 to include data from the International Bathymetric Chart of the Arctic Ocean (IBCAO), for the region north of 64N and also updates for shallower water regions off India, the Korean Peninsula and around South Afriaca, using data extracted from Electronic Navigation Charts (ENCs). The grid is available to download, in netCDF format, for free from the internet. Free software is available for viewing and accessing data from the grid in netCDF and ASCII. This includes an option to export the grid in an ASCII form suitable for conversion to an ESRI raster. The grid is also included in the GEBCO Digital Atlas DVD. It is not intended to make any further updates to this data set. In 2009, GEBCO released a new bathymetric grid, the GEBCO_08 Grid. This is a global terrain model at 30 arc-second intervals. It is largely based on a database of ship-track soundings with interpolation between soundings guided by satellite derived-gravity data.

This dataset consists of image mosaics of submarine canyons off Morocco collected using TOBI side-scan sonar on RV Maria S. Merian cruise MSM32, which occurred between 25 September and 30 October 2013. Imaging was conducted using a TOBI deep tow sidescan sonar, a high-resolution 2D seismic system consisting of a 150m long 88 channel digital streamer and a standard GI-gun. This cruise formed the field component of NERC Discovery Science project ‘How do submarine landslides disintegrate and form long run-out turbidity currents in the deep ocean, and how erosive are these flows?’ The study aimed to generate the first ever field dataset tracing a large-scale submarine landslide and its associated sediment-gravity flow from source-to-sink. This resulting dataset will aim to answer three important science questions: 1) How quickly do large submarine landslides disintegrate into long run-out sediment flows, and how is this process influenced by shape of the slope? 2) How efficiently do landslides remove failed material, i.e. what proportion of landslide debris is deposited on the slope and how much transforms into a flow that is transported distally? 3) How much sediment is incorporated into the flow through seafloor erosion, and where does most of this erosion take place? The Discovery Science project was composed of Standard Grant reference NE/J012955/1 and was led by Professor Russell Barry Wynn (National Oceanography Centre, Science and Technology). Funding ran from 07 June 2013 to 06 June 2014. Data have been received by BODC as raw files from the RRS James Cook and are available on request from BODC enquiries.

A set of historical tide gauge sea level records from Alicante (Spanish Mediterranean coast) have been recovered from logbooks stored at the Spanish National Geographical Institute (IGN). Sea level measurements have been digitised, quality-controlled and merged into two consistent sea level time series. Vertical references among instruments benchmarks have been derived from high precision vertical levelling surveys. Earlier observations are daily averages and more recent data are hourly values. The observations are from 7 different tide gauge records in Alicante outer harbour (Alicante I) and five tide gauge series in Alicante inner harbour (Alicante II). The sea level record in Alicante starts in 1870 with daily averaged values until the 1920s and hourly afterwards, and is still in operation, thus representing the longest tide gauge sea level time series in the Mediterranean Sea. The sea level at Alicante I has been measured by tide pole, floating gauge, mechanical recorder, digital recorder and since 2014 by radar gauge. The sea level at Alicante II has been measured by floating gauge, digital recorder and from 2014 onwards by radar gauge. This scarcity of long-term sea-level observations, as well as their uneven geographical distribution is a major challenge for climate studies that address, for example, the quantification of mean sea-level rise at centennial time scales, the accurate assessment of sea-level acceleration or the long-term changes in sea-level extremes that are vital for coastal risk assessments. This dataset represents an additional effort of sea-level data archaeology and aims at preserving the historical scientific heritage that has been up to now stored in old archives in non-electronic format. The research was partially funded by the Spanish Ministry of Science, Innovation and Universities. A further series was rescued from Santander under the same initiative.

The GEBCO_2021 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 2.2 of the SRTM15+ data set between latitudes of 50 degrees South and 60 degrees North. This data set is a fusion of land topography with measured and estimated seafloor topography. This version of SRTM15+ is similar to version 2.1 [Tozer et al., 2020] with minor updates. Version 2.2 uses predicted depths based on the V29 gravity model [Sandwell et al., 2019] and approximately 400 small areas containing suspect data were visually identified and removed from the grid. 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_2021 Grid represents all data within the 2021 compilation. The compilation of the GEBCO_2021 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 gridded bathymetric data sets are supplied by the Regional Centers as sparse grids, i.e. only grid cells that contain data were populated, were included on to the base grid without any blending. 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 primary GEBCO_2021 grid contains land and ice surface elevation information - as provided for previous GEBCO grid releases. In addition, for the 2021 release a version with under-ice topography/bathymetry information for Greenland and Antarctica is also available. The GEBCO_2021 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 data set comprises 2193 profiles of turbidity from an area of the Severn Estuary (UK) between the Shoots and Bridgwater Bay between 1974 and 1978. The data were collected as analogue records of continuous vertical profiles on a time series cross-section basis, where possible, over 13.5 hours from a drifting ship. All measurements were collected between 0 m and 39 m depth. The data coverage is derived from 172 stations along 17 survey lines, the density of coverage varying between 1 and 99 records per station. Each analogue record was digitised as approximately 200 pairs of XY coordinates. The X ordinates were then converted to depth (in metres) using a depth calibration and the Y ordinates to parts per million (PPM) of sediment using siltmeter calibration data. The Fluid Mud data bank was designed by the (former) Institute of Oceanographic Sciences (IOS) Taunton, UK, and the data were originally stored at IOS on a PDP 11 computer. They were then moved to an Oracle RDBMS at the British Oceanographic Data Centre (BODC) and stored as the Bristol Channel Suspended Sediments Data Bank.

This dataset consists of depth-averaged eastward and northward current components. Also present is the sea surface height above sea level. The dataset is a gridded dataset, with grid resolution of 1.85 km. It covers the entire Irish Sea area, with a precise range from -2.7 degrees longitude to -7 degrees longitude and from 51 degrees latitude to 56 degrees latitude. The data are 30 minute averages and cover the period from 01 January 1996 to 01 January 2007. The dataset was generated by the Proudman Oceanographic Laboratory Coastal Ocean Modelling System coupled with the Wave Modelling model (POLCOMS-WAM) as part of the Natural Environment Research Council (NERC) CoFEE project which ran from April 2007 to September 2010. The depth-averaged eastward and northward current components and sea surface height were used as input conditions into a coastal processes and sediment transport model which looked at the response of the north Liverpool coastline to extreme flooding events. The dataset was generated by the Proudman Oceanographic Laboratory (since April 2010, part of the UK National Oceanography Centre). The dataset consists of 264 data files in Climate and Forecast (CF) compliant NetCDF format.

The dataset consists of northward and eastward baroclinic and barotropic current vectors derived from a 40 year run of the Proudman Oceanographic Laboratory Coastal Ocean Modelling System (POLCOMS) numerical model, run from 01 January 1964 to 31 December 2004. The dataset consists of 41 data files in Climate and Forecast (CF) compliant NetCDF format. The data are supplied as a gridded dataset covering the entire northwest European continental shelf and extending out into the Atlantic Ocean. The grid resolution varies from 7.8 km to 14.2 km along the longitudinal axis and is at 12.3 km on the latitudinal axis. The model contains 40 depth layers. The model run was from 01 January 1964 to 31 December 2004. The barotropic currents were generated every 20 seconds, while the baroclinic currents were generated every 300 seconds. These generated currents were then averaged over a 25 hour tidal cycle to remove tidal current influence from the data. The dataset consists of 41 data files in Climate and Forecast (CF) compliant NetCDF format. The model simulations were run on the HECTOR supercomputer managed by the University of Edinburgh. The data were generated by the National Oceanography Centre (NOC) Liverpool as part of Natural Environment Research Council (NERC) National Capability (NC) funding looking at multi-decadal variability and trends in temperature of the northwest European continental shelf.

The data set comprises time series of wave height and period data from in-situ wave recorders at fixed locations. Principal parameters are significant/characteristic wave height and mean zero crossing period - usually derived from the analysis of 20 or 30 minute recordings taken at intervals of the order of 3 hours. Data holdings include over 1500 recording months of data from some 60 sites across the continental shelf areas around the British Isles and the NE Atlantic between 1954 and 1995. Recording periods vary from 2 months at some sites to over 15 years. The longer series are noted here: Channel Lightvessel (49 54.4N, 002 53.7W; 01 Sep 1979 - 31 Dec 1985); Dowsing Lightvessel (53 34.0N, 000 50.2W; 01 May 1970 - 30 Apr 1971; 01 Nov 1975 - 30 Jun 1981; 01 Jan 1982 - 31 Dec 1982; 01 Jan 1984 - 31 Dec 1984); Ocean Weather Ship Lima (57 00.0N, 020 00.0W; 01 Jan 1975 - 31 Dec 1983); Saint Gowan Lightvessel (51 30.0N, 004 59.8W; 01 Aug 1975 - 31 Jul 1976; 01 Dec 1976 - 31 Dec 1983); Seven Stones Lightvessel (50 03.8N, 006 04.4W; 31 Jan 1962 - 31 Jan 1963; 01 Jan 1968 - 31 Dec 1969; 01 Jul 1971 - 30 Jun 1974; 01 Apr 1975 - 31 Dec 1985). The data originate primarily from UK and Irish laboratories and are managed by the British Oceanographic Data Centre. Data collection is ongoing at some sites (for example, Seven Stones Lighvessel) but these data are not managed by BODC. They are part of the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) wavenet network.