Carmarthen Bay, Bristol Channel

Mineralogical composition; Electrical conductivity of the water column; Vertical velocity of the water column (currents); Sediment grain size parameters; Salinity of the water column; Horizontal velocity of the water column (currents); Temperature of the water column; Concentration of suspended particulate material in the water column; Spectral wave data parameters; Transmittance and attenuance of the water column; Bathymetry and Elevation

Sea level recorders; current meters; radar altimeters; discrete water samplers; particulates samplers; sediment grabs; unconsolidated sediment corers; transmissometers; CTD; current profilers; sidescan sonars; single-beam echosounders; sediment settling tubes; wave recorders

The data set comprises the data collected during RRS Challenger cruise 74B (1 - 10 February 1991). The cruise was designed to study wave and current dissipation and sediment transport in a high energy environment. The study took place off Carmarthen Bay in the Bristol Channel, which is an area of strong tidal currents, frequently experiencing large waves including long period swell from the Atlantic. Eleven moorings were deployed and recovered during the cruise, at two stations separated by about 10 nautical miles. The instruments included two STABLE rigs to measure bottom boundary layer structure (these failed to record any data), two ADCP rigs with pressure recorders, two near surface and two near bottom S4 current meters, A WAVEC buoy, a waverider buoy and a meteorological buoy (which failed to record any data). Limited data were obtained from the moored ADCPs and S4s. In addition, the area around the two stations were surveyed using a sidescan sonar and an echosounder. 68 CTD casts (temperature, salinity, transmittance), 48 grab samples and 3 sediment cores were also taken. Suspended sediment samples were obtained on four occasions, from five heights, using an array of sediment streamer traps. Ten water bottle samples were taken during CTD dips to determine suspended sediment load to calibrate the transmissometers. The ship's radar was used to obtain wave spectra. Continuous surface underway measurements of temperature, salinity and transmittance were recorded, together with current profiles from the shipborne ADCP.

Wolf, J. (1991) Wave and current dissipation and sand transport in the Bristol Channel, RRS Challenger Cruise 74B, 1-10 February 1991., Proudman Oceanographic Laboratory Cruise Report No. 11, 29pp.

Proudman Oceanographic Laboratory
Joseph Proudman Building 6 Brownlow Street
Liverpool
Merseyside
L3 5DA
United Kingdom