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Cruise inventory

RRS John Murray JM20/79

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS John Murray (74MJ)
Cruise identifierJM20/79
Cruise period1979-12-05 — 1979-12-17
Port of departureBarry, United Kingdom
Port of returnBarry, United Kingdom
Objectives1) To test the assertion that mean currents in the uppermost few metres of the wave field can be measured adequately using vector-averaging current sensors mounted on a moored surface following bouy

2) To test an experimental mooring designed for this purpose, and to investigate its suitability for mooring arrays of pitch/rool wave bouys

3) to see whether the technique provides sufficient accuracy for shear to be detected in the near surface region

4) to provide further testing for the vector averagineg electromagnetic current meter recently developed at IOS
Chief scientistPeter G Collar (Institute of Oceanographic Sciences Wormley Laboratory)
Cruise reportRRS John Murray JM20/79 cruise report john_murray20_79.pdf — access key 'C' (0.22 MB) 
Ocean/sea areas 
GeneralInner Seas off the West Coast of Scotland
Track chartsRRS John Murray JM20/79 cruise track — trk2396.html
Physical oceanography 
Current metersQuantity: number of stations = 1
Description: 4 current meters, durations various, from 2 to 6 weeks.
Routine standard measurementsDescription: synoptic,usually hourly or 3-hourly.
Other meteorological measurementsDescription: ship-borne wave recorder.3 records of 20 minutes, 1 of 12 minutes.
Other meteorological measurementsDescription: sea and swell