Cruise inventory

RRS James Clark Ross JR20051205 (JR138, JR139)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS James Clark Ross (74JC)
Cruise identifierJR20051205 (JR138, JR139)
Cruise period2005-12-05 — 2005-12-17
Port of departureStanley, Falkland Islands (Malvinas)
Port of returnRothera, Antarctica
ObjectivesEleventh occupation of the Drake Passage section (Burdwood Bank to Elephant Island), established during the World Ocean Circulation Experiment as repeat section SR1b, first occupied by Southampton Oceanography Centre (now the National Oceanography Centre) in collaboration with the British Antarctic Survey in 1993, and re-occupied most years since then.

The main objectives are:
1. To determine the interannual variability of the position, structure and transport of the Antarctic Circumpolar Current (ACC) in Drake Passage
2. To examine the fronts associated with the ACC, and to determine their positions and strengths
3. By comparing geostrophic velocities with those measured directly (by the lowered ADCP), to determine the size of ageostrophic motions, and to attempt to estimate the barotropic components
4. To examine the temperature and salinity structure of the water flowing through Drake Passage, and to identify thereby the significant water masses
5. To calculate the total flux of water through Drake Passage by combining all available measurements

This cruise was run in conjunction with JR138
Chief scientistKate Stansfield (University of Southampton School of Ocean and Earth Science)
ProjectDrake Passage repeats
Coordinating bodyNOCS
Cruise reportRRS James Clark Ross JR20051205 (JR138, JR139) cruise report jr139.pdf — access key 'C' (3.54 MB) 
Ocean/sea areas 
GeneralSouth West Atlantic Ocean (limit 20W)
SpecificSouth Atlantic Ocean, Drake Passage
Track chartsRRS James Clark Ross JR20051205 (JR138, JR139) cruise track — jr139trk.pdf (0.60 MB) 
Physical oceanography 
Surface measurements underway (T,S)Quantity: activity duration in days = 9
Description: Oceanlogger: SBE45 Conductivity, temperature, depth. Turner Designs 10-AU Fluorometer. Continuous sampling. Intake ~ 6-m depth.
CTD stationsQuantity: number of samples = 328
Description: Water samples for salinometer salinity determinations at the 30 CTD stations
CTD stationsQuantity: number of stations = 30
Description: Vertical profiles, continuous recording. Temperature, conductivity, pressure, oxygen, transmissivity, fluorescence.
CTD stationsQuantity: number of samples = 328
Description: SBE35 High Precision Thermometer. 11 seconds of data recorded every time a water sample was collected
Current profiler (eg ADCP)Quantity: activity duration in days = 9
Description: Velocity profiles. Vessel-mounted Acoustic Doppler Current Profiler (VM-ADCP) 75 kHz RD Instruments Ocean Surveyor (OS75) 8-m vertical bins, 120 second averages
Current profiler (eg ADCP)Quantity: number of stations = 30
Description: Lowered ADCP measurements, single downward looking 300kHz RDI. Full-depth profiles.
Routine standard measurementsQuantity: activity duration in days = 9
Description: Standard meterological measurements by automated sensor package on JCR