Cruise inventory

RRS Discovery DY018 (GApr04 Leg1)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74EQ)
Cruise identifierDY018 (GApr04 Leg1)
Cruise period2014-11-09 — 2014-12-02
StatusCompleted
Port of departureFalmouth, United Kingdom
Port of returnSouthampton, United Kingdom
PurposeResearch
ObjectivesCruise DY018 was the autumn/winter cruise associated with the NERC/Defra-funded Shelf Sea Biogeochemistry research programme. The work was largely focused on pelagic biogeochemical processes on the Celtic Sea shelf and the adjacent shelf slope, deliberately targeting the time of year when the surface mixed layer is deepening convectively towards winter. There were 5 main objectives:
1. Carry out 2 process stations, one on the shelf and one at the shelf edge, to measure biogeochemical rates through the water column.
2. Carry out 2 transects of stations over the shelf slope to the shelf edge, measuring biogeochemical states and also iron chemistry.
3. Carry out a broader survey of biogeochemical states and iron chemistry across the wider shelf.
4. Service an array of moored instrumentation in the central Celtic Sea.
5. Deploy both long-term and short-term gliders in the Celtic Sea and at the shelf edge. The short-term gliders were recovered before the end of the cruise.
The cruise has highly successful, largely because of remarkably good weather considering the expectations for the time of year. Process stations were carried out in the central Celtic Sea (CCS) and at the shelf edge (CS2), each lasting about 3 days. Work on these stations typically comprised CTDs for water sample collection and autotrophic and bacterial rate measurements; use of the Marine Snowcatcher and Standalone Pumps for particle characterisation and remineralisation rates; WP2 zooplankton net hauls for biomass, species and grazing rates; and cores for very-near-bed water sampling and ammonia release experiments. Two cross-slope transects, each consisting of 7 stations between depths of 2500m and 200m, were carried out to measure iron chemistry and radium. A line of CTD stations was run from the shelf edge, through the central Celtic Sea mooring site and up into the Celtic Deep (A). Measurements at these stations were made for basic iron chemistry and biogeochemical states. An array or moorings in the central Celtic Sea was recovered and redeployed. A separate wirewalker mooring was deployed at the start of the cruise, recovered/redeployed partway through the cruise (because it had come adrift from its bottom anchor) and recovered towards the end of the cruise. 5 gliders were deployed, Two were recovered towards the end of the cruise, as planned. One of the long-term gliders running along a line over the shelf slope appears to have been lost already.
Chief scientistJonathan Sharples (University of Liverpool Department of Earth, Ocean and Ecological Sciences)
ProjectShelf Sea Biogeochemistry
Coordinating bodyNatural Environment Research Council (NERC)
Cruise reportRRS Discovery DY018 (GApr04 Leg1) cruise report dy018.pdf — access key 'C' (3.90 MB) 
Ocean/sea areas 
GeneralCeltic Sea
Track chartsRRS Discovery DY018 (GApr04 Leg1) cruise track — dy018trk.pdf (00 MB) 
Measurements 
Physical oceanography 
Surface measurements underway (T,S)Description: Underway TS, fluorescence, transmittance, met
CTD stationsQuantity: number of profiles = 96
Description: CTD with additional sensors for: chl fluorescence, turbidity, transmittance, dissolved oxygen, PAR
Subsurface temperature measurementsQuantity: activity duration in hours = 31
Description: Ship-deployed temperature logger chain
Transparency (eg transmissometer)Description: Underway TS, fluorescence, transmittance, met
Transparency (eg transmissometer)Quantity: number of profiles = 96
Description: CTD with additional sensors for: chl fluorescence, turbidity, transmittance, dissolved oxygen, PAR
Optics (eg underwater light levels)Quantity: number of profiles = 96
Description: CTD with additional sensors for: chl fluorescence, turbidity, transmittance, dissolved oxygen, PAR
Current profiler (eg ADCP)Quantity: number of profiles = 96
Description: LADCP on CTD
Current profiler (eg ADCP)Description: Ship's ADCPs
Chemical oceanography 
OxygenQuantity: number of profiles = 96
Description: DO on CTD
OxygenQuantity: number of measurements = 20
Description: Oxygen-Argon measurements of net primary production
Other dissolved gasesQuantity: number of measurements = 20
Description: Oxygen-Argon measurements of net primary production
Other dissolved gasesQuantity: number of profiles = 60
Description: N2 and methane
PhosphateQuantity: number of profiles = 80
Description: Inorganic nutrients on CTD
NitrateQuantity: number of profiles = 80
Description: Inorganic nutrients on CTD
NitriteQuantity: number of profiles = 80
Description: Inorganic nutrients on CTD
AmmoniaQuantity: number of profiles = 80
Description: Inorganic nutrients on CTD
SilicateQuantity: number of profiles = 80
Description: Inorganic nutrients on CTD
AlkalinityQuantity: number of profiles = 81
Description: DIC and alkalinity on CTD
pHQuantity: number of profiles = 81
Description: DIC and alkalinity on CTD
Trace elementsQuantity: number of measurements = 5
Description: Standalone pumps
Trace elementsQuantity: number of profiles = 29
Description: Iron measurements on CTD
RadioactivityQuantity: number of profiles = 29
Description: Radium measurements on CTD
IsotopesQuantity: number of measurements = 20
Description: Oxygen-Argon measurements of net primary production
Biology and fisheries 
Primary productivityQuantity: number of profiles = 4
Description: CTD-based sampling for incubation rate measurements of phytoplankton
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of profiles = 60
Description: Chlorophyll on CTD
Phytoplankton pigs (eg chlorophyll, fluorescence)Description: Underway TS, fluorescence, transmittance, met
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of profiles = 96
Description: CTD with additional sensors for: chl fluorescence, turbidity, transmittance, dissolved oxygen, PAR
Particulate organic matter (inc POC, PON)Quantity: number of profiles = 60
Description: POM and DOM on CTD
Particulate organic matter (inc POC, PON)Quantity: number of measurements = 5
Description: Standalone pumps
Dissolved organic matter (inc DOC)Quantity: number of profiles = 60
Description: POM and DOM on CTD
Biochemical measurements (eg lipids, amino acids)Quantity: number of measurements = 5
Description: Standalone pumps
PhytoplanktonQuantity: number of profiles = 60
Description: Phytoplankton and flow cytometer asmples on CTD
ZooplanktonQuantity: number of hauls = 91
Description: Zooplankton nets (WP2) for zooplankton biomass and grazing/excretion rates
SestonQuantity: number of measurements = 18
Description: Marine Snowcatcher particle characterisation
Pelagic bacteria/micro-organismsQuantity: number of measurements = 18
Description: Marine Snowcatcher remineralisation rates
Pelagic bacteria/micro-organismsQuantity: number of measurements = 18
Description: Marine Snowcatcher remineralisation rates
Pelagic bacteria/micro-organismsQuantity: number of profiles = 4
Description: CTD-based sampling for remineralisation rates
Pelagic bacteria/micro-organismsQuantity: number of profiles = 4
Description: CTD-based sampling for incubation rate measurements of bacteria
Meteorology 
Routine standard measurementsDescription: Underway TS, fluorescence, transmittance, met
Geology and geophysics 
Core - soft bottomQuantity: number of cores = 17
Description: Ammonia release from sediments (NIOZ box cores)
Moorings, landers, buoys 
Physical oceanography 
CTD stations49° 23' 59" N  8° 35' 59" W — 1 x wirewalker profiling CTD mooring, with a CTD profiling through the upper 100m of water. Mooring was deployed on 11 Nov. The mooring came adrift from its bottom weight about 15 Nov. It was recovered close to the deployment site (and still profiling correctly) on 21 Nov, redeployed on 22 Nov and finally recovered on 26 Nov.
Subsurface temperature measurements49° 23' 59" N  8° 35' 59" W — Main project mooring array, depoyed originally in March 2014. Depth=150m. 1 x seabed frame with 2 ADCPs. 1 x In-line mooring with 4 ADCPs. 1 x mooring string with temperature, temperature-depth and CTD loggers every 10 to 5 metres from the seabed to about 15m from the sea surface. Moorings were recovered on 20 Nov and redeployed on 21 Nov.
Current profiler (eg ADCP)49° 23' 59" N  8° 35' 59" W — Main project mooring array, depoyed originally in March 2014. Depth=150m. 1 x seabed frame with 2 ADCPs. 1 x In-line mooring with 4 ADCPs. 1 x mooring string with temperature, temperature-depth and CTD loggers every 10 to 5 metres from the seabed to about 15m from the sea surface. Moorings were recovered on 20 Nov and redeployed on 21 Nov.
Other physical oceanographic measurements49° 23' 59" N  8° 35' 59" W — Glider (Slocum) with CTD and turbulence (microrider), profiling in the vicinity of the moorings (above) for the duration of the cruise. Deployed 11 Nov, recovered 26 Nov.
Other physical oceanographic measurements48° 21' 0" N  9° 41' 59" W — 2 gliders (Slocums) deployed Nov 15. These gliders were to stay patrolling over the shelf slope until March 2015. One of them appeared to have become stuck on the seabed before the end of the cruise.
Other physical oceanographic measurements48° 34' 0" N  9° 31' 59" W — Glider (slocum) deployed 18 Nov. This glider will patrol between the shelf edge and the moorings (above) until March 2015.
Other physical oceanographic measurements49° 23' 59" N  8° 35' 59" W — Glider (seaglider) with CTD and nitrate sensor, profiling in the vicinity of the moorings (above). Deployed 11 Nov, but failed. Recovered 21 Nov and redeployed 22 Nov, recovered 26 Nov.
Chemical oceanography 
Nitrate49° 23' 59" N  8° 35' 59" W — Glider (seaglider) with CTD and nitrate sensor, profiling in the vicinity of the moorings (above). Deployed 11 Nov, but failed. Recovered 21 Nov and redeployed 22 Nov, recovered 26 Nov.
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)49° 23' 59" N  8° 35' 59" W — 1 x wirewalker profiling CTD mooring, with a CTD profiling through the upper 100m of water. Mooring was deployed on 11 Nov. The mooring came adrift from its bottom weight about 15 Nov. It was recovered close to the deployment site (and still profiling correctly) on 21 Nov, redeployed on 22 Nov and finally recovered on 26 Nov.
Data held at BODC 
Series/Profiles 
93  CTD/STD cast
Density of the water column
Transmittance and attenuance of the water column
Visible waveband radiance and irradiance measurements in the water column
Electrical conductivity of the water column
Chlorophyll pigment concentrations in water bodies
Vertical spatial coordinates
Salinity of the water column
Optical backscatter
Temperature of the water column
Reference numbers
Dissolved oxygen parameters in the water column
Density of the water column
Transmittance and attenuance of the water column
Visible waveband radiance and irradiance measurements in the water column
Electrical conductivity of the water column
Chlorophyll pigment concentrations in water bodies
Vertical spatial coordinates
Salinity of the water column
Optical backscatter
Temperature of the water column
Reference numbers
Dissolved oxygen parameters in the water column

BODC idDate/TimeLocationDoc.
13720912014-11-21 08:43 49° 24' 23" N  8° 35' 57" W  View metadata report for BODC series reference number 1372091
13721092014-11-21 18:18 49° 23' 56" N  8° 35' 3" W  View metadata report for BODC series reference number 1372109
13721102014-11-22 05:05 49° 23' 15" N  8° 35' 13" W  View metadata report for BODC series reference number 1372110
13721222014-11-22 06:52 49° 23' 36" N  8° 35' 13" W  View metadata report for BODC series reference number 1372122
13721342014-11-22 08:05 49° 23' 36" N  8° 35' 13" W  View metadata report for BODC series reference number 1372134
13721462014-11-23 01:00 48° 23' 58" N  9° 54' 3" W  View metadata report for BODC series reference number 1372146
13721582014-11-23 05:03 48° 23' 58" N  9° 54' 3" W  View metadata report for BODC series reference number 1372158
13721712014-11-23 06:30 48° 23' 58" N  9° 54' 4" W  View metadata report for BODC series reference number 1372171
13721832014-11-23 10:26 48° 24' 36" N  9° 53' 22" W  View metadata report for BODC series reference number 1372183
13721952014-11-23 21:35 48° 25' 19" N  9° 52' 43" W  View metadata report for BODC series reference number 1372195
13722022014-11-24 02:25 48° 25' 46" N  9° 52' 15" W  View metadata report for BODC series reference number 1372202
13722142014-11-24 06:09 48° 26' 14" N  9° 51' 46" W  View metadata report for BODC series reference number 1372214
13722262014-11-24 09:00 48° 29' 29" N  9° 48' 30" W  View metadata report for BODC series reference number 1372226
13722382014-11-24 13:17 48° 34' 15" N  9° 30' 34" W  View metadata report for BODC series reference number 1372238
13722512014-11-24 14:09 48° 34' 15" N  9° 30' 34" W  View metadata report for BODC series reference number 1372251
13722632014-11-25 05:11 49° 24' 4" N  8° 35' 0" W  View metadata report for BODC series reference number 1372263
13722752014-11-25 12:17 49° 23' 57" N  8° 34' 55" W  View metadata report for BODC series reference number 1372275
13722872014-11-25 15:41 49° 24' 52" N  8° 35' 35" W  View metadata report for BODC series reference number 1372287
13722992014-11-26 08:05 49° 24' 20" N  8° 35' 44" W  View metadata report for BODC series reference number 1372299
13723062014-11-26 12:32 49° 23' 39" N  8° 25' 52" W  View metadata report for BODC series reference number 1372306
13723182014-11-27 18:16 50° 12' 28" N  7° 27' 46" W  View metadata report for BODC series reference number 1372318
13723312014-11-28 11:46 50° 37' 30" N  6° 56' 33" W  View metadata report for BODC series reference number 1372331
13723432014-11-28 14:52 50° 49' 41" N  6° 40' 1" W  View metadata report for BODC series reference number 1372343
13723552014-11-10 16:35 49° 23' 59" N  8° 34' 20" W  View metadata report for BODC series reference number 1372355
13723672014-11-11 10:55 49° 23' 54" N  8° 34' 43" W  View metadata report for BODC series reference number 1372367
13723792014-11-12 10:56 49° 23' 57" N  8° 34' 28" W  View metadata report for BODC series reference number 1372379
13723802014-11-14 23:30 48° 12' 22" N  10° 3' 15" W  View metadata report for BODC series reference number 1372380
13723922014-11-15 06:46 48° 14' 21" N  9° 57' 54" W  View metadata report for BODC series reference number 1372392
13724112014-11-15 20:16 48° 20' 23" N  9° 42' 24" W  View metadata report for BODC series reference number 1372411
13724232014-11-16 06:39 48° 22' 12" N  9° 37' 42" W  View metadata report for BODC series reference number 1372423
13724352014-11-16 13:10 48° 22' 41" N  9° 36' 29" W  View metadata report for BODC series reference number 1372435
13724472014-11-16 18:55 48° 24' 31" N  9° 31' 33" W  View metadata report for BODC series reference number 1372447
13724592014-11-16 22:43 48° 25' 42" N  9° 28' 1" W  View metadata report for BODC series reference number 1372459
13724602014-11-18 09:15 48° 34' 16" N  9° 30' 39" W  View metadata report for BODC series reference number 1372460
13724722014-11-19 10:02 48° 34' 16" N  9° 30' 34" W  View metadata report for BODC series reference number 1372472
13724842014-11-22 21:35 48° 22' 6" N  9° 55' 3" W  View metadata report for BODC series reference number 1372484
13724962014-11-23 03:27 48° 23' 58" N  9° 54' 3" W  View metadata report for BODC series reference number 1372496
13725032014-11-23 08:43 48° 24' 36" N  9° 53' 22" W  View metadata report for BODC series reference number 1372503
13725152014-11-23 19:52 48° 25' 19" N  9° 52' 43" W  View metadata report for BODC series reference number 1372515
13725272014-11-24 00:44 48° 25' 46" N  9° 52' 15" W  View metadata report for BODC series reference number 1372527
13725392014-11-24 04:59 48° 26' 14" N  9° 51' 46" W  View metadata report for BODC series reference number 1372539
13725402014-11-24 08:05 48° 29' 29" N  9° 48' 30" W  View metadata report for BODC series reference number 1372540
13725522014-11-27 08:26 49° 36' 18" N  8° 19' 47" W  View metadata report for BODC series reference number 1372552
13725642014-11-27 11:27 49° 47' 40" N  8° 3' 46" W  View metadata report for BODC series reference number 1372564
13725762014-11-27 14:24 50° 0' 47" N  7° 47' 43" W  View metadata report for BODC series reference number 1372576
13725882014-11-27 17:15 50° 12' 28" N  7° 27' 46" W  View metadata report for BODC series reference number 1372588
13726072014-11-28 20:02 51° 12' 46" N  6° 7' 54" W  View metadata report for BODC series reference number 1372607
13726192014-11-29 14:13 49° 24' 15" N  8° 35' 7" W  View metadata report for BODC series reference number 1372619
13726202014-11-30 10:07 49° 24' 18" N  8° 34' 35" W  View metadata report for BODC series reference number 1372620
13726322014-12-01 06:47 50° 2' 2" N  4° 22' 14" W  View metadata report for BODC series reference number 1372632
13716282014-11-10 05:12 49° 24' 4" N  8° 34' 48" W  View metadata report for BODC series reference number 1371628
13716412014-11-10 09:11 49° 24' 0" N  8° 34' 33" W  View metadata report for BODC series reference number 1371641
13716532014-11-10 12:28 49° 23' 54" N  8° 34' 35" W  View metadata report for BODC series reference number 1371653
13716652014-11-11 09:18 49° 23' 53" N  8° 34' 43" W  View metadata report for BODC series reference number 1371665
13716772014-11-11 12:14 49° 23' 53" N  8° 34' 43" W  View metadata report for BODC series reference number 1371677
13716892014-11-11 14:08 49° 23' 53" N  8° 34' 45" W  View metadata report for BODC series reference number 1371689
13716902014-11-11 18:12 49° 23' 57" N  8° 34' 38" W  View metadata report for BODC series reference number 1371690
13717082014-11-12 05:15 49° 23' 55" N  8° 34' 35" W  View metadata report for BODC series reference number 1371708
13717212014-11-12 09:11 49° 23' 56" N  8° 34' 35" W  View metadata report for BODC series reference number 1371721
13717332014-11-12 12:30 49° 23' 57" N  8° 34' 26" W  View metadata report for BODC series reference number 1371733
13717452014-11-13 08:18 49° 16' 0" N  8° 44' 59" W  View metadata report for BODC series reference number 1371745
13717572014-11-13 11:40 49° 7' 33" N  8° 54' 20" W  View metadata report for BODC series reference number 1371757
13717692014-11-13 13:16 49° 7' 41" N  8° 54' 17" W  View metadata report for BODC series reference number 1371769
13717702014-11-13 15:03 49° 7' 41" N  8° 54' 17" W  View metadata report for BODC series reference number 1371770
13717822014-11-13 17:39 49° 0' 0" N  9° 2' 45" W  View metadata report for BODC series reference number 1371782
13717942014-11-13 18:45 49° 0' 0" N  9° 2' 45" W  View metadata report for BODC series reference number 1371794
13718012014-11-13 21:18 48° 51' 14" N  9° 11' 56" W  View metadata report for BODC series reference number 1371801
13718132014-11-13 22:52 48° 51' 14" N  9° 11' 56" W  View metadata report for BODC series reference number 1371813
13718252014-11-14 00:18 48° 51' 14" N  9° 11' 56" W  View metadata report for BODC series reference number 1371825
13718372014-11-14 02:35 48° 43' 6" N  9° 21' 4" W  View metadata report for BODC series reference number 1371837
13718492014-11-14 13:15 48° 34' 15" N  9° 30' 34" W  View metadata report for BODC series reference number 1371849
13718502014-11-14 19:56 48° 12' 21" N  10° 3' 14" W  View metadata report for BODC series reference number 1371850
13718622014-11-15 01:50 48° 12' 22" N  10° 3' 15" W  View metadata report for BODC series reference number 1371862
13718742014-11-15 04:15 48° 14' 22" N  9° 57' 54" W  View metadata report for BODC series reference number 1371874
13718862014-11-15 09:25 48° 20' 26" N  9° 42' 14" W  View metadata report for BODC series reference number 1371886
13718982014-11-15 18:29 48° 20' 24" N  9° 42' 24" W  View metadata report for BODC series reference number 1371898
13719052014-11-15 22:46 48° 20' 23" N  9° 42' 24" W  View metadata report for BODC series reference number 1371905
13719172014-11-16 02:13 48° 22' 12" N  9° 37' 42" W  View metadata report for BODC series reference number 1371917
13719292014-11-16 04:56 48° 22' 12" N  9° 37' 42" W  View metadata report for BODC series reference number 1371929
13719302014-11-16 11:36 48° 22' 41" N  9° 36' 29" W  View metadata report for BODC series reference number 1371930
13719422014-11-16 14:35 48° 22' 41" N  9° 36' 29" W  View metadata report for BODC series reference number 1371942
13719542014-11-16 17:39 48° 24' 31" N  9° 31' 33" W  View metadata report for BODC series reference number 1371954
13719662014-11-16 23:39 48° 25' 42" N  9° 28' 1" W  View metadata report for BODC series reference number 1371966
13719782014-11-17 12:25 48° 34' 15" N  9° 30' 34" W  View metadata report for BODC series reference number 1371978
13719912014-11-17 15:42 48° 34' 15" N  9° 30' 34" W  View metadata report for BODC series reference number 1371991
13720052014-11-18 05:16 48° 34' 15" N  9° 30' 37" W  View metadata report for BODC series reference number 1372005
13720172014-11-18 08:10 48° 34' 16" N  9° 30' 39" W  View metadata report for BODC series reference number 1372017
13720292014-11-18 10:02 48° 34' 16" N  9° 30' 39" W  View metadata report for BODC series reference number 1372029
13720302014-11-18 12:11 48° 34' 16" N  9° 30' 39" W  View metadata report for BODC series reference number 1372030
13720422014-11-19 12:17 48° 34' 16" N  9° 30' 34" W  View metadata report for BODC series reference number 1372042
13720542014-11-19 13:58 48° 34' 16" N  9° 30' 34" W  View metadata report for BODC series reference number 1372054
13720662014-11-20 02:11 48° 34' 24" N  9° 30' 22" W  View metadata report for BODC series reference number 1372066
13720782014-11-20 09:32 49° 23' 33" N  8° 35' 33" W  View metadata report for BODC series reference number 1372078
Discrete samples 
24  CTD frame plus rosette samplerAmmonium and ammonia concentration parameters in water bodies
Chlorophyll pigment concentrations in water bodies
Silicate concentration parameters in the water column
Salinity of the water column
Nitrate concentration parameters in the water column
Nitrite concentration parameters in the water column
Phosphate concentration parameters in the water column
81  Sample taken from ship's non-toxic supplySalinity of the water column
25  Ammonium and ammonia concentration parameters in water bodies
Chlorophyll pigment concentrations in water bodies
Silicate concentration parameters in the water column
Salinity of the water column
Nitrate concentration parameters in the water column
Nitrite concentration parameters in the water column
Phosphate concentration parameters in the water column