Cruise inventory

RRS James Clark Ross JR20061206 (JR155, JR163, JR164)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS James Clark Ross (74JC)
Cruise identifierJR20061206 (JR155, JR163, JR164)
Cruise period2006-12-06 — 2006-12-17
StatusCompleted
Port of departureStanley, Falkland Islands (Malvinas)
Port of returnRothera, Antarctica
PurposeResearch
ObjectivesTwelfth occupation of the Drake Passage section, 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:
(i) to determine the interannual variability of the position, structure and transport of the Antarctic Circumpolar Current (ACC) in Drake Passage;
(ii) to examine the fronts associated with the ACC, and to determine their positions and strengths;
(iii) 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;
(iv) to examine the temperature and salinity structure of the water flowing through Drake Passage, and to identify thereby the significant water masses;
(v) to calculate the total flux of water through Drake Passage by combining all available measurements.
ACCLAIM Bottom Pressure Recorders have been used for making measurements of the Antarctic Circumpolar Current (ACC) since 1988, initially in the Scotia Sea and then later across the Drake Passage between the Falkland Islands and the Antarctic peninsula. Some of the Bottom Pressure Recorders (BPRs) are combined with Inverted Echo Sounders (IES). During this cruise, one BPR and one BPR/IES were recovered and re-deployed in the Drake Passage. The Sea Level Recorders at Stanley, Falkland Islands, Vernadsky and Rothera Research Stations in Antarctica, were also serviced.

JR155 was part of a continuing series as part of an AFI project (NERC NER/G/S/2002/00024 Biogeochemical Particle Flux Study in Marguerite Bay Antarctic Peninsula AFI4/13 PIs Jickells, Clarke, Brandon and Meredith) to study the physical and chemical properties, primary productivity processes and sedimentation processes in Marguerite Bay. The work is designed to augment the ongoing BAS Rothera Biogeochemical Times Series (RaTS) programme in Ryder Bay in northern Marguerite Bay, and to extend the programme into the open waters of Marguerite Bay. The sampling is therefore undertaken at two sites, the RaTS station in Ryder Bay and in the deeper water within Marguerite Bay itself. The cruise also contributed to another AFI project (NERC AFI4/02) PIs Elderfield, Ganeshram, Rickerby and de la Rocha "Behaviour of trace elements and isotope ratios of sea-ice brine and microaalgae: reconstructing the Antarctic sea-ice environment." In this second season (2006/7), moorings deployed earlier in the project were continued through a further full season and additional sediment sampling was undertaken. Hence the aims of JR155 were:
1. recover, service and redeploy the moorings previously deployed on JR136/7 in 2006,
2. conduct CTD casts to describe the physical structure of the water column and to provide water samples for nutrient and particulate matter analyses,
3. take box cores at both sites.

The locations were, as on previous cruises for this project, one 'deep' mooring 22 miles from Rothera research station with a ~840m water column depth and one 'shallow' mooring at the Ryder Bay site (RaTS) 2 miles from Rothera with a ~500 m water column depth.
Chief scientistAdam P Williams (National Oceanography Centre, Southampton), Rachel Hadfield (National Oceanography Centre, Southampton), Tim Jickells (University of East Anglia School of Environmental Sciences)
ProjectDrake Passage repeats
Cruise reportRRS James Clark Ross JR20061206 (JR155, JR163, JR164) cruise report jr155.pdf — access key 'C' (1.02 MB)  RRS James Clark Ross JR20061206 (JR155, JR163, JR164) cruise report jr163.pdf (1.57 MB)  RRS James Clark Ross JR20061206 (JR155, JR163, JR164) cruise report jr164.pdf (0.19 MB) 
Ocean/sea areas 
GeneralSouth West Atlantic Ocean (limit 20W)
Southern Ocean
SpecificDrake Passage. Marguerite Bay.
Track chartsRRS James Clark Ross JR20061206 (JR155, JR163, JR164) cruise track — jr155trk.pdf (00 MB) 
Measurements 
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.
Water bottle stationsQuantity: number of samples = 368
Description: Water samples for salinometer salinity determinations at the 30 CTD stations
Water bottle stationsQuantity: number of stations = 2
Description: 2 CTD stations with water samples collected for nutrient analysis
CTD stationsQuantity: number of stations = 31
Description: Vertical profiles, continuous recording. Temperature, conductivity, pressure, oxygen, transmissivity, fluorescence.
CTD stationsQuantity: number of stations = 2
Description: 2 CTD stations with water samples collected for nutrient analysis
CTD stationsQuantity: number of samples = 368
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)
Chemical oceanography 
SilicateQuantity: number of samples = 56
Description: Biogenic Silica
Other chemical oceanographic measurementsQuantity: number of samples = 56
Description: Particulate Inorganic Matter
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of samples = 131
Description: Chlorophyll
Particulate organic matter (inc POC, PON)Quantity: number of samples = 53
Description: Particulate Organic Matter
Meteorology 
Routine standard measurementsQuantity: activity duration in days = 9
Description: Standard meterological measurements by automated sensor package on JCR
Geology and geophysics 
Core - soft bottomQuantity: number of stations = 2
Description: 2 box core stations
Moorings, landers, buoys 
Physical oceanography 
Current meters67° 56' 35" S  68° 22' 51" W — Sediment traps and current meters recovered and deployed
Sea level (inc. bot. press., inverted echosounder)60° 51' 0" S  54° 42' 46" W — bottom pressure recorder and inverted echo sounder. Deployed Dec 2005, recovered Dec 2006. Drake South.
Sea level (inc. bot. press., inverted echosounder)54° 56' 35" S  58° 21' 18" W — bottom pressure recorder deployed Dec 2006. Drake North
Sea level (inc. bot. press., inverted echosounder)54° 56' 35" S  58° 21' 24" W — Bottom pressure recorder deployed 2005, recovered Dec 2006. Drake North
Sea level (inc. bot. press., inverted echosounder)60° 51' 1" S  54° 42' 47" W —
Biology and fisheries 
Sediment traps67° 56' 35" S  68° 22' 51" W — Sediment traps and current meters recovered and deployed
Data held at BODC 
Series/Profiles 
1  Acoustic doppler current profiler
Platform or instrument orientation
Acoustic backscatter in the water column
Metadata parameters
Vertical spatial coordinates
Horizontal velocity of the water column (currents)
Reference numbers
Date and time
Platform or instrument orientation
Acoustic backscatter in the water column
Metadata parameters
Vertical spatial coordinates
Horizontal velocity of the water column (currents)
Reference numbers
Date and time

BODC idDate/TimeLocationDoc.
7706682006-12-17 13:57:37  — 2007-04-13 10:57:37 67° 34' 0" S  68° 14' 0" W  View metadata report for BODC series reference number 770668
3  Moored CTD
Moored instrument depth
Density of the water column
Electrical conductivity of the water column
Salinity of the water column
Temperature of the water column
Reference numbers
Date and time
Moored instrument depth
Density of the water column
Electrical conductivity of the water column
Salinity of the water column
Temperature of the water column
Reference numbers
Date and time

BODC idDate/TimeLocationDoc.
7761662006-12-17 19:00:02  — 2007-04-09 08:00:02 67° 34' 0" S  68° 14' 0" W  View metadata report for BODC series reference number 776166
7762092006-12-17 19:00:02  — 2007-04-09 08:00:02 67° 34' 0" S  68° 14' 0" W  View metadata report for BODC series reference number 776209
7762342006-12-17 19:00:02  — 2007-04-09 08:00:02 67° 34' 0" S  68° 14' 0" W  View metadata report for BODC series reference number 776234
2  Water temperature and/or salinity monitor
Sea level
Temperature of the water column
Reference numbers
Date and time
Sea level
Temperature of the water column
Reference numbers
Date and time

BODC idDate/TimeLocationDoc.
7759742006-12-17 19:00:02  — 2007-04-09 08:00:02 67° 34' 0" S  68° 14' 0" W  View metadata report for BODC series reference number 775974
7773172006-12-17 19:00:02  — 2007-04-09 08:00:02 67° 34' 0" S  68° 14' 0" W  View metadata report for BODC series reference number 777317