The Marine Environment Monitoring and Assessment National database (MERMAN) is a national database which holds and provides access to data collected under the Clean Safe Seas Environmental Monitoring Programme (CSEMP) formerly the National Marine Monitoring Programme (NMMP). The data collected are the responsibility of the Competent Monitoring Authorities (CMAs) who collect the samples from stations in UK waters using water sampling techniques, trawls, nets or grabs. The CMAs then send the collected samples to accredited laboratories where they are analysed. A weighting is calculated, based on the quality of the analysis. The weighting score incorporates the laboratory accreditation, reference material, inter-laboratory comparisons, detection limits, uncertainties and standard deviations. Where data do not meet a threshold score they are given a status of ‘FAIL’ and although they are stored they are not made available to external users. The MERMAN contaminants and biological effects in sediment data start in 1987 with greater use of the database occurring from 1997 onwards. Data are submitted by the CMAs annually and an annual submission may include updates to legacy data to provide additional data or improve data/metadata. The data held in MERMAN fulfils the UK's mandatory monitoring requirements under the Oslo and Paris Convention (OSPAR) Joint Assessments and Monitoring Programme (JAMP). These data are used in support of European Commission (EC) directives and national assessments, such as Charting Progress 2 and are also supplied to the European Marine Observation and Data Network (EMODNET).

The dataset contains hydrographic, biogeochemical and biological measurements of ocean and seabed sediment properties. Hydrographic profiles provided measurements of temperature, salinity, dissolved oxygen and fluorescence to accompany biogeochemical and biological samples, including concentrations of nutrients, particulate organic carbon (POC) and particulate organic nitrogen (PON). Emphasis was placed on the collection of benthic data, with numerous core samples being collected and analysed for pigments, biomarkers, lipids and other organic compounds. Samples were also collected and analysed for Holothurian species, while a large volume in situ filtration system was used to measure biogeochemical variables including POC and PON, and particulate iron. Station data were supplemented by continuous underway measurements of bathymetry, current velocities, sea surface salinity, temperature, fluorescence and beam attenuation across the survey area. These were accompanied by underway measurements of surface meteorological parameters including irradiance, air temperature, humidity, sea level pressure and wind velocities. The data were collected across the Crozet Plateau in the Southern Indian Ocean between 1st December 2005 and 14th January 2006 on RRS Discovery cruise D300. Data collection focused on four sites, with repeated hydrographic profiles, water and sediment samples collected at each location. In total, 89 instrumentation deployments were carried out at the four stations, including a conductivity-temperature-depth (CTD) package and a Megacorer (for sediment sampling). The underway system utilised a hull-mounted acoustic Doppler current profiler (ADCP) as well as a thermosalinograph and other standard surface hydrographic and meteorological instruments. Further data were collected using a variety of equipment including an otter trawl (net) and submersible cameras but these data are currently held by the data originators and are undergoing processing so are not included in the parameter and instrument lists above. The principal objective of Benthic CROZEX was to assess the manner in which biogeochemical composition and flux of organic matter to the deep-sea floor drives benthic community structure, dynamics and diversity at sites with contrasting primary production regimes. Investigators from British Antarctic Survey (BAS), Natural History Museum (NHM), National Oceanographic Centre (NOC) and the National University of Ireland, Galway (NUIG) were involved. Data management is being undertaken by the British Oceanographic Data Centre (BODC) but data processing is ongoing and various data are yet to be submitted to BODC.

The dataset comprises physical, biogeochemical and biological oceanographic, surface meteorological and benthic measurements. Hydrographic profiles including temperature, salinity, fluorescence, transmissance and suspended sediment concentration were collected at numerous stations, while surface hydrographic (fluorescence, transmissance, sea surface temperature, salinity) and meteorological (irradiance, air temperature, humidity, wind speed/direction) data were collected across the survey areas. Sediment, pore water and water column samples were also collected for biogeochemical analysis, as were biological samples for the purposes of species classification and abundance analyses. The data were collected across the Indian Ocean, Arabian Sea and Pakistan margin areas between March and October 2003. Data collection was undertaken by the RRS Charles Darwin during four cruises: CD145 (12 March 2003 to 9 April 2003), CD146 (12 April 2003 to 30 May 2003), CD150 (22 August 2003 to 15 September 2003) and CD151 (17 September 2003 to 20 October 2003). Conductivity-temperature-depth (CTD) profilers with auxiliary sensors, benthic samplers and nets were deployed from the ship, while underway sensors provided continuous surface ocean, meteorological and bathymetric data. The study was designed to investigate an oxygen-minimum zone (OMZ) in the northern Arabian Sea. Chief Investigators include Gregory L Cowie (University of Edinburgh School of GeoSciences) and Brian J Bett (Southampton Oceanography Centre), while other institutions including the Dunstaffnage Marine Laboratory, University of Liverpool and Netherlands Institute of Ecology were also involved in the research. Data management is being undertaken by BODC. Some of the data are still undergoing processing at BODC and further data are expected from originators in the future.