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  • 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.

  • The data set consists of bathymetric contours, at 100m intervals, from a depth of 100m to 5000m. The data were digitised from two charts of the Northeast Atlantic compiled by geoscientists at the Institute of Oceanographic Sciences (IOS), Wormley, Surrey and published by the UK Hydrographic Office, Taunton. Admiralty Chart C6566: Bathymetry of the northeast Atlantic (IOS Sheet 1) - 'Reykjanes Ridge and Rockall Plateau' by A.S. Laughton, D.G. Roberts & P.M. Hunter published in February 1982 and covering the area (47° to 64°N, 13° to 37°W). Admiralty Chart C6567: Bathymetry of the northeast Atlantic (IOS Sheet 2) - 'Continental Margin around the British Isles' by D.G. Roberts, P.M. Hunter & A.S. Laughton published in February 1977 and covering the area (47° to 64°N, 6°E to 18°W). The data set is included in the Centenary Edition of the GEBCO Digital Atlas (GDA) as sheet G.02. Please note that within the GDA data set some areas covered by sheets IOS sheets 1 and 2 have been replaced by higher resolution data sets. Through the GDA software interface the data may be exported in ASCII or shapefile format.

  • The International Bathymetric Chart of the Arctic Ocean (IBCAO) Version 4.0 is a gridded continuous terrain model covering ocean and land of the Arctic region. The grid has been compiled from data covering approximately 14.2 percent of the Arctic seafloor with multibeam bathymetry and about 5.5 percent with other sources, excluding digitized depth contours. The grid-cell size (resolution) is 200x200 m on a Polar Stereographic projection, with the true scale set at a latitude of 75 deg N and a central meridian of 0 deg. The horizontal datum is WGS 84 and the vertical datum is assumed Mean Sea Level. IBCAO Version 4.0 has been compiled with support from the Nippon Foundation-GEBCO-Seabed 2030 Project, an international effort whose goal it is to see the entire world ocean mapped by 2030. A geographic version of the Polar Stereographic grid serves as input to the General Bathymetric Chart of Oceans (GEBCO) global gridded terrain model.

  • The General Bathymetric Chart of the Oceans (GEBCO) Digital Atlas (GDA) contains global bathymetric data sets, consisting of the latest versions of GEBCO’s global gridded bathymetric data sets; global bathymetric contour and accompanying trackline control data sets; bathymetric contours and coastlines from the First Edition of the International Bathymetric Chart of the Mediterranean (IBCM); a set of digital global coastlines based on the World Vector Shoreline data set (coastlines south of 60S have been removed) at a range of scales from 1:43 million to 1:250,000; the SCAR coastline of Antarctica (version 3.0) at a range of scales from 1:30 million to 1:250,000; and a digital set of geographically referenced feature names including the International Hydrographic Organization (IHO)/Intergovernmental Oceanographic Commission (IOC) Gazetteer of Geographic Names of Undersea Features. The GEBCO dataset has global coverage and was first released in 1994. The contents of the GDA are updated periodically to include new versions of GEBCO’s bathymetric grids. The GDA is distributed on DVD and includes full documentation and a software interface for viewing and accessing the data sets.

  • This dataset includes two cruises of data collected to investigate Arctic hydrate dissociation as a consequence of climate change and to determine vulnerable methane reservoir and gas escape mechanisms. Work during both JR269A and JR269B was focused on two separate geographical areas. The first of these was west of Prins Karls Forland, in water depths of between 150 and 1200 m. At its landward end, this survey area crosses a region at water depths up to 400 m where a dense concentration of methane escape bubble plumes occur. The second survey area straddles the summit of the Vestnesa Ridge, in water depths of 1180 to 1400 m, and is also the site of methane escape bubble plumes within the water column and of fluid escape chimneys and pockmarks previously imaged at and beneath the sea bed. This area lies approximately 100 km west of the mouth of Kongsfjorden. Data collection took place between August 2011 and July 2012. The research expedition used a deep-towed, very high resolution seismic system to image the small-scale structures that convey gas to the seabed and to detect the presence of gas in the sediments. This was done in conjunction with an electromagnetic exploration system that uses a deep-towed transmitter and receivers on the seabed to derive the variations in electrical resistivity in the sediments beneath the seabed. The observations carried out on the two cruises included; underway, meteorological observations and echo sounder data, multichannel seismic reflection profiling data, wide angle seismic survey data, and ocean bottom seismometer (OBS) data, ocean bottom electro-magnetometer data and controlled source electromagnetic surveys (CSEM). The overall objectives of the project were to determine the spatial distribution of gas and hydrate accumulations beneath the sea bed; to investigate and understand gas transport and escape mechanisms, their spatial distribution, and the controls on these; and to quantify gas and hydrate saturation values in situ within the pore spaces of the shallow sediment reservoirs. The research is focused on specific areas where significant accumulations of methane hydrate and active methane venting through the sea floor were observed and documented during the earlier JR211 cruise in 2008. This is a NERC funded project hosted by University of Southampton. The data held at BODC include multichannel seismic reflection, TOPAS sub-bottom profiler and 2D seismic reflection data in SEG-Y format. No further data are expected.

  • 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.

  • A collection of raw water temperature-depth-time profiles were recorded from a selection of dive computers, underwater cameras and baseline Castaway microCTD devices. Data were collected at Oban recompression chamber (owned and managed by Tritonia Scientific), as well as during sea dives local to 56.42 N, 5.47W, over a two-week period between 08/01/2020 and 07/02/2020. A number of different devices and models were tested during the study. Chamber dives were undertaken to test and compare device response time (29 devices over 11 dives) and accuracy (6 replicate dives). This was followed by local sea dives to further compare device accuracy. During each pair of sea dives (6 total), half of the devices were mounted on a frame with the remainder worn by two divers. For the subsequent dives in each pair, each device was switched to the alternate mounting position. Dive profiles were exported from individual dive computers into Subsurface open source software, then exported in ssrf (XML) format for each week of data collection. Profiles from all dive computers were combined for analysis. Castaway microCTDs and Paralenz Dive Camera+ profiles were exported as individual CSV files per dive. Data were collected as part of Celia Marlowe’s PhD project at the University of East Anglia, which aimed to assess the precision, accuracy and uncertainty in water temperature profiles collected from devices commonly carried by Scuba divers. The PhD project is part of the Next Generation Unmanned Systems Science (NEXUSS) Centre for Doctoral Training, funded by the Natural Environment Research Council (NERC) and the Engineering and Physical Science Research Council (EPSRC) (NE/N012070/1), and is additionally supported by Cefas Seedcorn (DP901D). The diving and chamber tests were supported through a NERC National Facility for Scientific Diving grant (NFSD/17/02).

  • 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.

  • This data set consists of a bathymetric grid derived from multibeam bathymetry data from cruise JC071. The bathymetric grid was created by gridding the cleaned raw multibeam data from JC071 at 1/64 arc-minute intervals using a nearneighbour gridding algorithm from the Generic Mapping Tools (GMT) software system. The data set covers an approximate one degree square with the minimum and maximum longitude and latitude co-ordinates: 17.016667W-16.216667W; 48.78333N-49.28333N. This is located in the Northeast Atlantic Ocean area. The data were collected from 7th-8th May 2012 using an EM120 Multibeam Echo-sounder. The cruise was part of the Porcupine Abyssal Plain (PAP): sustained ocean observation project. The bathymetry data were collected on an opportunistic basis during the cruise. The cruise was operated by the National Oceanography Centre (NOC), equipment operated by National Marine Facilities Sea Systems. The bathymetric grid was created by BODC for contributing to the EMODnet High Resolution Seafloor Mapping (HRSM) Project.

  • 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.