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BODC Cruise Metadata Report for RRS Discovery (74E3) cruise D308

Introduction

This report collates information from the BODC cruise inventory and oceanographic databases. It presents

Cruise Inventory Information

Long name RRS Discovery (74E3) cruise D308
Short name D308
Objectives and Narrative RRS Discovery cruise 308 was the fourth field campaign of the project RAPID-WAVE (West Atlantic Variability Experiment), funded by the NERC Rapid Climate Change thematic programme (RAPID).

RAPID-WAVE aims at investigating how signals associated with changes in the Atlantic meridional overturning circulation propagate along the Atlantic deep western boundary current. As part of the project, two cruises took place in 2004. In the first one, a line of 6 Bottom Pressure Recorders (BPR) was deployed in an operation area approximately located at 36.5 N 67.5 W. In the second one, two additional lines of 6 BPRs and 5 CTD moorings each were deployed on the continental shelf break approximately south of St. Johns and southeast of Halifax, respectively.

The aim of D308 was to recover and redeploy the BPRs and moorings deployed in 2004 along the St. Johns and Halifax lines. In conjunction with the recovery/redeployment operations, CTD casts were planned to be carried out and to include helium, tritium and oxygen sampling (for calibration of the CTD oxygen sensor). Measurement of tritium-helium ratios provides estimates of ventilation age up to about 20 year and is therefore very useful for inferring timescales of water-mass age and tracer transport by the Atlantic deep western boundary current.

The cruise encountered mixed success as regards the recovery of instruments: only 50% of the BPRs and 20% of the moorings could be retreived. All planned CTD casts and sampling operations were completed.
Ship RRS Discovery
Departure Port St. John's, Canada
Departure Date 2006-07-24
Arrival Port St. John's, Canada
Arrival Date 2006-08-15
Principal Scientist(s) Miguel Angel Morales Maqueda (Proudman Oceanographic Laboratory)
Responsible Organisation Dunstaffnage Marine Laboratory
Associated Project(s) Rapid Climate Change (RAPID)
IHB Sea Areas Visited North West Atlantic Ocean (limit 40W)
Marsden Squares Visited 150/151
Work Area Description Continental slope southwest of Grand Banks, and continental slope southeast of Nova Scotia
Work Area Bounding Polygon 40N,70W; 50N,70W; 50N,50W; 40N,50W; 40N,70W
Southern Limit 40N
Northern Limit 50N
Western Limit 70W
Eastern Limit 50W

Cruise Inventory Datasets

Physical oceanography  
CTD stations Quantity: number of stations = 3
Description: CTD stations conducted with UKORS SeaBird 911+ instrument:- Site C1: 09/8/06, 21:52Z, 4560m depth, 41 48.0 N, 60 00.0 W Site C2: 10/8/06, 18:08Z, 4760m depth, 41 57.3 N, 56 34.0 W Site C3: 11/8/06, 11:37Z, 4910m depth, 42 06.0 N, 53 09.3 W  
CTD stations Quantity: number of stations = 6
Description: CTD stations conducted with UKORS SeaBird 911+ instrument:- Site A0: 29/7/06, 03:53Z, 1770m depth, 43 15.7 N, 52 11.2 W Site A1: 28/7/06, 22:59Z, 2205m depth, 43 13.4 N, 52 16.5 W Site A2: 28/7/06, 18:08Z, 2785m depth, 43 07.9 N, 52 23.6 W Site A3: 11/8/06, 21:52Z, 3150m depth, 42 55.7 N, 52 28.5 W Site A4: 12/8/06, 14:57Z, 3630m depth, 42 39.9 N, 52 38.7 W Site A5: 12/8/06, 09:35Z, 4080m depth, 42 29.1 N, 52 50.2 W For each of these stations, two 300kHz LADCPs (downward and upward-looking), an oxygen sensor, a fluorometer, a transmissometer, a back scatter sensor and an altimeter were fitted on the CTD frame  
CTD stations Quantity: number of stations = 8
Description: CTD stations conducted with UKORS SeaBird 911+ instrument:- Site B0: 01/8/06, 06:40Z, 1710m depth, 43 00.3 N, 60 55.4 W Site B1: 06/8/06, 14:38Z, 2180m depth, 42 55.4 N, 60 51.9 W Site B2: 01/8/06, 23:09Z, 2680m depth, 42 49.4 N, 60 46.3 W Site B2, 06/8/06, 11:47Z, 2660m depth, 42 50.0 N, 60 46.7 W Site B3: 04/8/06, 22:42Z, 3310m depth, 42 38.4 N, 60 41.0 W Site B4: 06/8/06, 21:49Z, 3660m depth, 42 25.7 N, 60 26.2 W Site B5: 04/8/06, 02:23Z, 4100m depth, 42 13.1 N, 60 16.6 W Site B5: 08/8/06, 00:36Z, 4020m depth, 42 15.1 N, 60 18.0 W For each of these stations, two 300kHz LADCPs (downward and upward-looking), an oxygen sensor, a fluorometer, a transmissometer, a back scatter sensor and an altimeter were fitted on the CTD frame Note that two CTD casts were carried out on site B2. The second one was needed to collect a near bottom sample that was omitted in the first cast. No other bottle samples were taken in this second cast. Note that two CTD casts were carried out on site B5. The second cast was made in order to calibrate the SBE37 instruments to be deployed in the UKORS moorings. No water samples were taken in this second cast.  
CTD stations Quantity: number of stations = 2
Description: CTD stations conducted with UKORS SeaBird 911+ instrument:- Test site: 25/7/06, 20:33Z, to 550 m, 43 43.1N 052 14.0W Test site: 27/7/06, 22:03Z, 3150m depth, 42 54.3N 52 28.8W For each of these stations, two 300kHz LADCPs (downward and upward-looking), an oxygen sensor, a fluorometer, a transmissometer, a back scatter sensor and an altimeter were fitted on the CTD frame  
Geochemical tracers (eg freons) Quantity: number of stations = 19
Description: Helium and tritium tracer samples were drawn from Niskin bottles on above CTD casts. Samples will be shipped back to UK. Between 11 and 16 helium/tritium samples were drawn from each cast. Six oxygen samples were also taken per cast for calibration of the oxygen sensor.  
Surface measurements underway (T,S) Quantity: activity duration in days = 21
Description: The Discovery "surfmet" package was switched on for the duration of the cruise, providing thermosalinograph measurements (sea surface temperature, conductivity, fluorescence, beam transmission) and meteorology measurements (barometric pressure, wind speed & direction, air temperature, humidity, photosynthetically-active radiation and total incidence radiation). True wind speed and direction (rather than relative to ship) were derived, and uncalibrated sea surface salinity.  
Chemical oceanography  
Oxygen Quantity: number of stations = 19
Description: Helium and tritium tracer samples were drawn from Niskin bottles on above CTD casts. Samples will be shipped back to UK. Between 11 and 16 helium/tritium samples were drawn from each cast. Six oxygen samples were also taken per cast for calibration of the oxygen sensor.  
Meteorology  
Incident radiation Quantity: activity duration in days = 21
Description: The Discovery "surfmet" package was switched on for the duration of the cruise, providing thermosalinograph measurements (sea surface temperature, conductivity, fluorescence, beam transmission) and meteorology measurements (barometric pressure, wind speed & direction, air temperature, humidity, photosynthetically-active radiation and total incidence radiation). True wind speed and direction (rather than relative to ship) were derived, and uncalibrated sea surface salinity.  
Routine standard measurements Quantity: activity duration in days = 21
Description: The Discovery "surfmet" package was switched on for the duration of the cruise, providing thermosalinograph measurements (sea surface temperature, conductivity, fluorescence, beam transmission) and meteorology measurements (barometric pressure, wind speed & direction, air temperature, humidity, photosynthetically-active radiation and total incidence radiation). True wind speed and direction (rather than relative to ship) were derived, and uncalibrated sea surface salinity.  
Geology and geophysics  
Single-beam echosounding Quantity: activity duration in days = 21
Description: The Simrad EA500 single-beam echosounder was switched on for the duration of the cruise. Corrected depth was calculated using Carter tables. Some manual cleaning of this data was done routinely.  

Cruise Inventory Mooring/Buoy Operations

Latitude Longitude Data type Description
42° 55' N 52° 30' W Other physical oceanographic measurements Site A3: Temporary current meter mooring deployed into 3220m, 11/8/06 (Jday 223), 21:24Z Heights of instruments above seafloor: 50, 500
42° 55' N 52° 29' W Other physical oceanographic measurements Site A3: Temporary current meter mooring recovered from 3220m, 12/8/06 (Jday 224), 21:51Z Heights of instruments above seafloor: 50, 500
42° 55' N 60° 51' W Other physical oceanographic measurements Site B1: CTD mooring, recovered from 2213m, 1/8/06 (Jday 213), 14:19Z Heights of instruments above seafloor: 100, 200*, 300, 400* (where * denotes CTD [Microcat with pressure sensor], and absence of * denotes CT logger)
42° 36' N 60° 37' W Other physical oceanographic measurements Site B3: CTD mooring, deployed into 3200m, 9/8/06 (Jday 221), 13:06Z Heights of instruments above seafloor: 0**, 250, 500*, 505***, 730, 980* (where ** denotes BPR, *** denotes current meter, * denotes CTD [Microcat with pressure sensor], and absence of * denotes CT logger)
42° 27' N 60° 25' W Other physical oceanographic measurements Site B4: Temporary current meter mooring deployed into 3650m, 5/8/06 (Jday 217), 22:30Z Heights of instruments above seafloor: 50, 500
42° 27' N 60° 25' W Other physical oceanographic measurements Site B4: Temporary current meter mooring recovered from 3650 m, 7/8/06 (Jday 219), 11:09 Heights of instruments above seafloor: 50, 500
42° 12' N 60° 18' W Other physical oceanographic measurements Site B5: CTD mooring, deployed into 4100m, 8/8/06 (Jday 220); 14:35Z Heights of instruments above seafloor: 0**, 250, 500*, 625, 775, 925* (where ** denotes BPR, * denotes CTD [Microcat with pressure sensor], and absence of * denotes CT logger)
43° 16' N 52° 11' W Sea level (inc. bot. press., inverted echosounder) Site A0: Bottom Pressure Recorder, recovered from 1807m, 26/7/06 (Jday 207), 12:25Z
43° 12' N 52° 15' W Sea level (inc. bot. press., inverted echosounder) Site A1: Bottom Pressure Recorder, recovered from 2227m, 26/7/06 (Jday 207), 16:12Z
43° 0' N 60° 54' W Sea level (inc. bot. press., inverted echosounder) Site B0: Bottom Pressure Recorder, deployed into 1822m, 1/8/06 (Jday 213), 12:00Z
43° 0' N 60° 54' W Sea level (inc. bot. press., inverted echosounder) Site B0: Bottom Pressure Recorder, recovered from 1838m, 1/8/06 (Jday 213), 11:36Z
42° 55' N 60° 51' W Sea level (inc. bot. press., inverted echosounder) Site B1: Bottom Pressure Recorder, deployed into 2212m, 1/8/06 (Jday 213), 16:46Z
42° 55' N 60° 51' W Sea level (inc. bot. press., inverted echosounder) Site B1: Bottom Pressure Recorder, recovered from 2217m, 1/8/06 (Jday 213), 16:15Z
42° 49' N 60° 46' W Sea level (inc. bot. press., inverted echosounder) Site B2: Bottom Pressure Recorder, deployed into 2704m, 6/8/06 (Jday 218), 10:45Z
42° 49' N 60° 46' W Sea level (inc. bot. press., inverted echosounder) Site B2: Bottom Pressure Recorder, recovered from 2714m, 1/8/06 (Jday 213), 22:47Z
42° 36' N 60° 37' W Sea level (inc. bot. press., inverted echosounder) Site B3: Bottom Pressure Recorder, deployed into 3255m (as part of UKORS mooring), 9/8/06 (jday 221), 13:06Z
42° 37' N 60° 36' W Sea level (inc. bot. press., inverted echosounder) Site B3: Bottom Pressure Recorder, recovered from 3221m, 2/8/06 (Jday 214), 16:10Z
42° 26' N 60° 28' W Sea level (inc. bot. press., inverted echosounder) Site B4: Bottom Pressure Recorder, deployed into 3655m, 8/8/06 (Jday 220), 19:19Z
42° 12' N 60° 18' W Sea level (inc. bot. press., inverted echosounder) Site B5: Bottom Pressure Recorder deployed into 4102m (as part of UKORS mooring), 8/8/06 (Jday 220), 14:35Z

Summary of BODC Data Holdings for the Cruise

National Oceanographic Database

Summary

# Series Instrument Description Parameters
5 Bottom pressure sensor tide gauge Date and time
Reference numbers
Sea level
Temperature of the water column
20 CTD/STD cast Chlorophyll pigment concentrations in water bodies
Density of the water column
Dissolved oxygen parameters in the water column
Salinity of the water column
Temperature of the water column
Vertical spatial coordinates
5 Moored CTD Date and time
Electrical conductivity of the water column
Reference numbers
Salinity of the water column
Temperature of the water column
4 Moored CTD Date and time
Electrical conductivity of the water column
Moored instrument depth
Reference numbers
Salinity of the water column
Temperature of the water column

Note: Parameter terms are taken from the BODC Parameter Discovery Vocabulary XML (SKOS)

Full List

BODC Reference Instrument Description Date/Time Location  
938401 Moored CTD 2006-08-09 14:04Z to 2007-10-06 12:34Z 42° 36' N, 60° 37' W Click for more
938413 Moored CTD 2006-08-09 14:02Z to 2007-10-06 12:32Z 42° 36' N, 60° 37' W Click for more
938425 Moored CTD 2006-08-08 15:24Z to 2007-10-06 16:24Z 42° 12' N, 60° 18' W Click for more
938437 Moored CTD 2006-08-08 15:23Z to 2007-10-06 16:23Z 42° 12' N, 60° 18' W Click for more
938449 Moored CTD 2006-08-08 15:58Z to 2007-10-06 16:28Z 42° 12' N, 60° 18' W Click for more
938505 Moored CTD 2006-08-09 14:05Z to 2007-10-06 12:36Z 42° 36' N, 60° 37' W Click for more
938517 Moored CTD 2006-08-09 14:03Z to 2007-10-06 12:33Z 42° 36' N, 60° 37' W Click for more
938529 Moored CTD 2006-08-08 15:26Z to 2007-10-06 16:26Z 42° 12' N, 60° 18' W Click for more
938530 Moored CTD 2006-08-08 15:18Z to 2007-10-06 16:48Z 42° 12' N, 60° 18' W Click for more
1040731 Bottom pressure sensor tide gauge 2006-08-01 20:07Z to 2008-02-06 17:52Z 43° 0' N, 60° 54' W Click for more
1040767 Bottom pressure sensor tide gauge 2006-08-06 16:07Z to 2007-10-07 12:36Z 42° 49' N, 60° 46' W Click for more
1040792 Bottom pressure sensor tide gauge 2006-08-09 17:52Z to 2007-10-06 12:06Z 42° 36' N, 60° 37' W Click for more
1040823 Bottom pressure sensor tide gauge 2006-08-08 21:07Z to 2007-09-29 19:05Z 42° 26' N, 60° 28' W Click for more
1040847 Bottom pressure sensor tide gauge 2006-08-08 18:52Z to 2007-10-06 16:36Z 42° 12' N, 60° 18' W Click for more
1069995 CTD/STD cast 2006-07-25 20:26Z 43° 43' N, 52° 13' W Click for more
1070007 CTD/STD cast 2006-07-27 21:59Z 42° 54' N, 52° 28' W Click for more
1070019 CTD/STD cast 2006-07-29 03:45Z 43° 15' N, 52° 11' W Click for more
1070020 CTD/STD cast 2006-07-28 22:57Z 43° 13' N, 52° 16' W Click for more
1070032 CTD/STD cast 2006-07-28 18:00Z 43° 7' N, 52° 23' W Click for more
1070044 CTD/STD cast 2006-08-11 21:45Z 42° 55' N, 52° 28' W Click for more
1070056 CTD/STD cast 2006-08-12 14:55Z 42° 40' N, 52° 39' W Click for more
1070068 CTD/STD cast 2006-08-12 09:27Z 42° 29' N, 52° 50' W Click for more
1070081 CTD/STD cast 2006-08-01 06:30Z 43° 0' N, 60° 55' W Click for more
1070093 CTD/STD cast 2006-08-06 15:03Z 42° 55' N, 60° 52' W Click for more
1070100 CTD/STD cast 2006-08-01 22:58Z 42° 49' N, 60° 46' W Click for more
1070112 CTD/STD cast 2006-08-06 11:44Z 42° 49' N, 60° 46' W Click for more
1070124 CTD/STD cast 2006-08-04 22:35Z 42° 38' N, 60° 40' W Click for more
1070136 CTD/STD cast 2006-08-06 21:45Z 42° 25' N, 60° 26' W Click for more
1070148 CTD/STD cast 2006-08-04 02:17Z 42° 13' N, 60° 16' W Click for more
1070161 CTD/STD cast 2006-08-08 01:24Z 42° 15' N, 60° 18' W Click for more
1070173 CTD/STD cast 2006-08-09 21:47Z 41° 48' N, 60° 0' W Click for more
1070185 CTD/STD cast 2006-08-10 18:03Z 41° 57' N, 56° 34' W Click for more
1070197 CTD/STD cast 2006-08-11 11:33Z 42° 6' N, 53° 9' W Click for more
1070204 CTD/STD cast 2006-08-02 22:50Z 42° 13' N, 60° 16' W Click for more

Project Database

# Events Gear Type Parameters Held
20 CTD frame plus rosette sampler Density of the water column
Chlorophyll pigment concentrations in water bodies
Salinity of the water column
Temperature of the water column
Dissolved oxygen parameters in the water column
8 Instrument mooring

Note: Parameter terms are taken from the BODC Parameter Discovery Vocabulary XML (SKOS)

References

Track Charts

Track Chart

Reports

Cruise Report