The data set comprises time series measurements from offshore pressure gauges mounted on the sea floor. The data holdings are approximately 250 observation months from 100 sites. The data have mainly been collected in the continental shelf seas around the British Isles. Data records contain date/time, total pressure and, occasionally, temperature. The sampling interval is typically 15 minutes or hourly, over deployment periods ranging from 1 to 6 months. Data were collected mainly by the Proudman Oceanographic Laboratory (POL), now the National Oceanography Centre (NOC) at Liverpool, and are managed by the British Oceanographic Data Centre (BODC).

The World Ocean Circulation Experiment (WOCE) sea level data set comprises data collected from approximately 160 tide gauge sites distributed around the world. The data are usually hourly heights of sea surface elevation, although some were collected and supplied at higher frequencies (i.e. 6 or 15 minute intervals) or as pressure values rather than elevations. The data are primarily from 1990 to 1998 (the WOCE period), but the dataset also includes historical data as a number of the tide gauges had been operating for many years. The total volume of data held is 3550 site years. A few sites have data extending back over 50 years and many over 20 years. The British Oceanographic Data Centre (BODC) was responsible, as a WOCE Data Assembly Centre (DAC), for assembling, quality controlling and disseminating this comprehensive sea level data set. Data were supplied by Argentina, Australia, Canada, Chile, China, Cuba, Denmark, Ecuador, France, Iceland, Japan, New Zealand, Peru, Philippines, Portugal, Russia, South Africa, Spain, Ukraine, the UK and the USA. Data quality control was carried out with the aid of sophisticated screening software which allows rapid inspection of the data. The sea level data were tidally analyzed and the residuals inspected. Parameters other than sea level, for example atmospheric pressure and sea surface temperature, were also visually inspected. This quality control identified spikes and gaps in the data in addition to timing problems and datum shifts. Any problems identified were resolved with the data supplier. Qualifying information accompanying the data was also checked and data documentation assembled. The data can be downloaded from the BODC web site, or made available on CD-ROM.

The dataset comprises scanned images of historical analogue charts and data ledgers from eight tide gauge sites around the UK. The sites include: Sheerness, Belfast, and several sites around Liverpool managed by the Mersey Docks and Harbour Company namely, Eastham, Gladstone, Hilbre, Princes Pier, Tranmere and Waterloo. The Sheerness ledger data represents some of the earliest records of sea level data in the UK and cover the periods - January 1870 to December 1881, July 1882 to October 1894 and December 1929 to April 1941. Data availability for the other sites are: Belfast analogue charts - 27 November 1901 to 24 May 1902; Princes Pier ledgers: - 1941 to 1950, 1951 to 1960 and 1961 to 1970; Eastham, Gladstone, Hilbre, Princes Pier, Tranmere and Waterloo ledgers: - 1982 to 1988. The data recorded in some of the ledgers also describe meteorological measurements for example, air pressure, air temperature, wind speed and direction, and precipitation and evaporation. Funding to rescue these historical sea level data came from the Marine Environmental Data and Information Network (MEDIN) and the British Oceanographic Data Centre (BODC).These images have now been added to the National Oceanographic Database and are freely available to registered users (subject to licence agreement).

The Global Sea Level Observing System (GLOSS) 'Delayed-mode' Data Assembly Centre at the British Oceanographic Data Centre (BODC) quality controls and archives high frequency (i.e. hourly or more frequent) global sea level data and any ancillary measurements (e.g. temperature, wind speed/direction, atmospheric pressure) that are included with the data. The tide gauges are situated on most coastlines, and data cover the Arctic to the Antarctic, and the Atlantic, Indian and Pacific oceans. The main component of GLOSS is the 'Global Core Network' (GCN) of 290 sea level stations around the world for long term climate change and oceanographic sea level monitoring. The Core Network is designed to provide an approximately evenly-distributed sampling. The GLOSS Long Term Trends (LTT) set of gauge sites (some, but not all, of which are in the GCN) are used for monitoring long term trends and accelerations in global sea level. The GLOSS altimeter calibration (ALT) set consists mostly of island stations, and provides a facility for mission intercalibrations. A GLOSS ocean circulation (OC) set, including in particular gauge pairs at straits and in polar area, complements altimetric coverage of the open deep ocean. Data exist from the mid 1800s up to the present day, with particularly long records from Newlyn, U.K.; Brest, France; Prince Rupert, Canada and Honolulu, San Diego and San Francisco, U.S.A.; Sea level has been measured by a variety of different instruments with the historical data mainly coming from mechanical float gauges. More recent technologies include acoustic, pressure, and radar instruments. GLOSS aims at the establishment of high quality global and regional sea level networks to create long‐term sea level records. These records, as well as being used in climate studies (sea level rise), are also used in oceanography (ocean currents, tides, surges), geodesy (national datum), geophysics and geology (coastal land movements) as well as various other disciplines. The programme became known as GLOSS as it provides data for deriving the 'Global Level of the Sea Surface'. GLOSS is an international programme conducted under the auspices of the Joint Technical Commission for Oceanography and Marine Meteorology (JCOMM) of the World Meteorological Organisation (WMO) and the Intergovernmental Oceanographic Commission (IOC). Data are collected by local agencies such as port authorities, universities and navies and sent to or downloaded by the data centre.

The Marine Autonomous Systems in Support of Marine Observations (MASSMO) campaign 4 dataset includes data collected by 8 submarine gliders, 2 wavegliders and one autonomous surface vehicle. The dataset comprises recovery version data. i.e. the data downloaded from a vehicle at the end of its mission. The data obtained from gliders operated by the University of East Anglia (UEA) is fully quality controlled. No quality control procedures have been applied to the data obtained from all other autonomous vehicles. Parameters observed include, temperature, salinity, chlorophyll fluorescence, optical backscatter, oxygen, acoustic noise and video data. The dataset was collected within the UK sector of the Faroe-Shetland Channel, focussing on the outer shelf and upper shelf. The work area had a bounding box of 58-62 degrees north and 2-9 degrees west. The MASSMO 4 campaign was run between 1st June 2017 until 7th June 2017 while platforms were deployed they were collecting data continuously. The dataset was collected using a mixture of three autonomous surface vehicles and eight submarine gliders. Glider sensor suites included CTD, bio-optics, oxygen optodes, and passive acoustic sensors. Additionally the surface vehicles were equipped with meteorological sensors and cameras. The campaign comprised a range of oceanographic data collection, but had a particular focus on passive acoustic monitoring of marine mammals and oceanographic features, and included development of near-real-time data delivery to operational data users. MASSMO 4 was co-ordinated by the National Oceanography Centre (NOC) in partnership with University of East Anglia (UEA), Plymouth Marine Laboratory (PML) and Scottish Association for Marine Science (SAMS). The mission was sponsored by Defence Science and Technology Laboratory (Dstl) and involved close co-operation with the NATO Centre for Maritime Research and Experimentation (CMRE) and UK Royal Navy, and was supported by several additional commercial, government and research partners.

The MASSMO 5 dataset includes the near real time transmitted EGO (Everyone’s Gliding Observatories) NetCDF versions of glider data collected by five submarine gliders across three deployment campaigns. Recovery versions of data downloaded from the all gliders with no quality assurance are also available on request. Glider sensor suites included CTD, bio-optics, and oxygen optodes. Parameters observed include, temperature, salinity, chlorophyll fluorescence, optical backscatter, and oxygen data. The MASSMO 5a mission focused on the period 23 Jun 2018 to 06 Jul 2018 and included three submarine glider deployments (UK glider deployments only are included in this dataset). All assets were deployed from NRV Alliance in partnership with NATO-CMRE, but were recovered prematurely due to vessel technical issues. The primary geographic focus of MASSMO 5 was the outer shelf and upper slope off northern Norway, in the region between Bear Island and southern Spitsbergen, but outside the 12 mile territorial limits of these islands. The MASSMO 5b mission occurred within the period 17-24 Oct 2018, a total of three ocean gliders were deployed. The primary geographic focus of MASSMO5b was the northern North Sea to the east of the Orkney archipelago. The MASSMO 5c mission was aborted and no data were collected. The MASSMO 5d mission occurred within period 26 Apr 2019 to 6 May 2019, there was deployment of a single ocean glider. The primary geographic focus of MASSMO 5d was the Faroe Shetland Channel. MASSMO 5 was co-ordinated by the National Oceanography Centre (NOC) in partnership with University of East Anglia (UEA), Plymouth Marine Laboratory (PML) and Scottish Association for Marine Science (SAMS). The mission was sponsored by Defence Science and Technology Laboratory (DSTL) and involved close co-operation with the NATO Centre for Maritime Research and Experimentation (CMRE) and UK Royal Navy, and was supported by several additional commercial, government and research partners.

A time series of ocean circulation in the North Atlantic from 1900-2018 was calculated using a number of gridded data products. These comprise the EN4.2.1 gridded temperature and salinity dataset (Good et al. 2013), using Gouretski and Reseghetti (2010) corrections (https://www.metoffice.gov.uk/hadobs/en4/download-en4-2-1.html), gridded satellite altimetry from the Copernicus Marine Environment Monitoring Service (CMEMS, http://marine.copernicus.eu) and gridded wind stress fields from the European Centre for Medium-Range Weather Forecasts (ECMWF, https://www.ecmwf.int). Both ERA-20C and ERA-Interim products were obtained to cover the periods 1900-1978 and 1979-2018 respectively.

This Met/Ocean data bank comprises wave, current, water temperature and surface meteorology (air temperature, humidity and wind) data collected at 11 off-shore sites on the UK continental shelf, between 1973 and 1988. Three hourly wave data (short term statistics) and hourly wind observations together with atmospheric pressure, air temperature and, occasionally, sea surface temperature were measured at weather ships (W.S.) Stevenson (61 20.0N, 000 00.0E from 1973 - 1976), Fitzroy (60 00.0N, 004 00.0W from 1973 - 1976) and Boyle (50 40.0N, 007 30.0W from 1974 - 1977). Moored current meter measurements were also made at 2 to 4 depths at each site. Three-hourly measurements of sea temperature, air temperature, barometric pressure, relative humidity, wind speed and wind direction were collected at the National Data Buoy DB/1 site (48 43.0N, 008 58.0W) between 1978 and 1982. Directional spectra of the wave field were also derived from measurements of heave, pitch and roll of the buoy, while surface currents were measured hourly. DB/1 was succeeded by DB/2 (located at 48 44.0N, 008 50.0W from 1984 - 1986 and at 58 59.0N, 007 13.0W from 1986 - 1988) and DB/3 (60 30.9N, 002 52.0W from 1984 - 1988). Met/Ocean data and directional wave spectra are available from these sites, comprising hourly recordings of wind speed and direction, maximum wind gust speed, air temperature, relative humidity, barometric pressure (and pressure trend over three hours), sea temperature, significant wave height and period, maximum wave height, swell wave height, period and direction, wind wave height and period, current speed and direction. The directional wave spectra consist of the 9 co- and quad- spectral densities for 51 frequency slots, plus derived height, period, direction and directional spread of all waves, wind waves, swell waves and spectral peak wave period. The UKOOA dataset also includes measurements from four platforms, with short term wave statistics, hourly wind observations, atmospheric pressure, air temperature and occasionally sea surface temperature data available from Forties (57 45.0N, 001 00.0E) between 1974 and 1980; Brent (61 04.0N, 001 43.0E) between 1975 and 1980; and Beryl/Frigg (59 35.0N, 001 40.0E) between 1979 and 1982. One dimensional wave spectra and meteorological data are available from Foula (60 08.0N, 002 59.0W) between 1977 and 1979. All data were collected by the UK Offshore Operators Association (UKOOA) and are stored at the British Oceanographic Data Centre (BODC).

This dataset consists of observations from two autonomous underwater gliders deployed by the University of East Anglia, UK and Sultan Qaboos University, Oman. The two Seagliders, Humpback (serial number SG579) and Orca (serial number SG510), collected data to investigate physical-biological interactions in the water column. The gliders were deployed in the Gulf of Oman approximately 10 km from Muscat, at the 120 m isobath. Both gliders repeatedly surveyed a 76 km section across the shelf, continental slope and open ocean between 24°15' N, 59° E and 23°39.5' N, 58°39' E. Humpback, SG579, obtained 1,424 vertical profiles over a 91 day period (04 March 2015 to 03 June 2015), repeating the section 24 times. Orca, SG510, obtained 1,646 vertical profiles over a 109 day period (09 December 2015 to 27 March 2016), repeating the section 28 times. The glider data were processed using the UEA Seaglider Toolbox and standard techniques were used for calibration of the data. The data are held at BODC as a series of netCDF, .eng and .log files alongside a .mat file containing all processed data.