Cruise inventory

RRS Discovery DY026A

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74EQ)
Cruise identifierDY026A
Cruise period2014-08-03 — 2014-08-14
StatusCompleted
Port of departureSouthampton, United Kingdom
Port of returnSouthampton, United Kingdom
PurposeResearch
ObjectivesDY26A formed part of the NERC shelf sea biogeochemistry programme. It had four principal objectives
1. To continue the seasonal time series sampling at three key sites in the Celtic Sea (Shelf break, Candyfloss, Celtic Deep).
2. To provide sampling opportunities for the Shelf sea biogeochemistry students
3. To obtain samples of sinking particulate organic matter at differing stages of the tidal cycle to examine the role of tidal resuspension on elemental cycling beneath the thermocline.
4. To trial autonomous nitrate sensors CTDs and gliders as part of the Sensors on Gliders programme

Objective 1: We conducted CTD casts at each key site, sampling for DIC and nitrate concentrations to evaluate the differential uptake and remineralisation of these tracers which is key to the operation of the shelf sea pump. In addition we made at each site many of the rate measurements the programme needs to make to understand the differential elemental cycling.
Objective 2: Each SSB student got a good range of sampling opportunities at various sites in varying weather conditions.
Objective 3: Following the standard SSB observations outlined in objective 1 we undertook a highly temporally resolved timeseries of observations at the Celtic Deep. This comprised hourly CTDs with very high resolution sampling near the bed coupled to hourly snowcatcher deployments and near bottom respiration, bacterial production and nitrification measurements. Following this we revisited the same site over a tidal cycle and collected near bed suspended material for similar biological rate measurements.
Objective 4: The Sensors on gliders programme has integrated a nitrate sensor into a glider. This combination was trialled at the shelf break and on one further occasion during the cruise. Both deployments produced useful data. In addition the nitrate sensor itself was deployed on the CTD in standalone mode on two occasions with extended bottle stops to allow reliable measurements to be made.
Chief scientistRichard Sanders (National Oceanography Centre, Southampton)
ProjectShelf Sea Biogeochemistry
Coordinating bodyNatural Environment Research Council (NERC)
Ocean/sea areas 
GeneralCeltic Sea
Measurements 
Physical oceanography 
CTD stationsQuantity: number of stations = 33
Description: Temperature and Salinity were measured continuously on 33 CTD stations
Chemical oceanography 
OxygenQuantity: number of stations = 33
Description: Dissolved oxygen, total nitrogen and phosphorus and a range of organic tracers such as amino acids were sampled from 6-10 bottles on 33 CTD casts
Carbon dioxideQuantity: number of samples = 10
Description: Samples for Alkalinity and TCO2 were taken on 10 CTD stations at 6 depths in the vertical.
Other dissolved gasesQuantity: number of stations = 10
Description: Oxygen/ Argon ratios were measured on water from 10 CTD stations.
PhosphateQuantity: number of stations = 33
Description: Inorganic nutrients were measured at 6-10 depths on CTD casts and on experiments undertaken to examine zooplankton metabolism
Total - PQuantity: number of stations = 33
Description: Dissolved oxygen, total nitrogen and phosphorus and a range of organic tracers such as amino acids were sampled from 6-10 bottles on 33 CTD casts
NitrateQuantity: number of stations = 33
Description: Inorganic nutrients were measured at 6-10 depths on CTD casts and on experiments undertaken to examine zooplankton metabolism
NitriteQuantity: number of stations = 33
Description: Inorganic nutrients were measured at 6-10 depths on CTD casts and on experiments undertaken to examine zooplankton metabolism
Total - NQuantity: number of stations = 33
Description: Dissolved oxygen, total nitrogen and phosphorus and a range of organic tracers such as amino acids were sampled from 6-10 bottles on 33 CTD casts
AmmoniaQuantity: number of stations = 33
Description: Inorganic nutrients were measured at 6-10 depths on CTD casts and on experiments undertaken to examine zooplankton metabolism
SilicateQuantity: number of stations = 33
Description: Inorganic nutrients were measured at 6-10 depths on CTD casts and on experiments undertaken to examine zooplankton metabolism
AlkalinityQuantity: number of samples = 10
Description: Samples for Alkalinity and TCO2 were taken on 10 CTD stations at 6 depths in the vertical.
Biology and fisheries 
Primary productivityQuantity: number of stations = 10
Description: Size fractionated Phytoplankton Productivity and Chlorophyll Concentrations were measured on water from 10 CTD stations.
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of stations = 10
Description: Size fractionated Phytoplankton Productivity and Chlorophyll Concentrations were measured on water from 10 CTD stations.
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of samples = 10
Description: HPLC and Lugols samples were taken from CTD bottles fired in the deep Chlorophyll maxima. Similar observations and samples were made using samples from Marine snowcatchers triggered above and below the thermocline.
Particulate organic matter (inc POC, PON)Quantity: number of stations = 33
Description: Dissolved oxygen, total nitrogen and phosphorus and a range of organic tracers such as amino acids were sampled from 6-10 bottles on 33 CTD casts
Dissolved organic matter (inc DOC)Quantity: number of stations = 33
Description: Dissolved oxygen, total nitrogen and phosphorus and a range of organic tracers such as amino acids were sampled from 6-10 bottles on 33 CTD casts
Biochemical measurements (eg lipids, amino acids)Quantity: number of stations = 33
Description: Dissolved oxygen, total nitrogen and phosphorus and a range of organic tracers such as amino acids were sampled from 6-10 bottles on 33 CTD casts
ZooplanktonQuantity: number of hauls = 52
Description: Net hauls were undertaken on 52 Occasions. Samples were vertically resolved, collected at day and night and size segregated (>63 microns and >200 microns)
ZooplanktonQuantity: number of samples = 10
Description: HPLC and Lugols samples were taken from CTD bottles fired in the deep Chlorophyll maxima. Similar observations and samples were made using samples from Marine snowcatchers triggered above and below the thermocline.
Pelagic bacteria/micro-organismsQuantity: number of measurements = 10
Description: Bacterial Production measurements were made on water collected using CTD samplers and Marine Snowcatchers.
Other biological/fisheries measurementQuantity: number of measurements = 10
Description: Respiration measurements were made on water collected using CTD samplers and Marine Snowcatchers.
Other biological/fisheries measurementQuantity: number of deployments = 43
Description: 43 deployments of marine snowcatchers were undertaken
Other biological/fisheries measurementQuantity: number of measurements = 10
Description: Ammonification and Nitrification measurements were made on water collected using CTD samplers and Marine Snowcatchers.
Geology and geophysics 
Core - soft bottomQuantity: number of cores = 15
Description: A NIOZ box corer was used on 15 occasions. Experimental work on ammonium release was undertaken and samples preserved.
Moorings, landers, buoys 
Physical oceanography 
Other physical oceanographic measurements51° 12' 34" N  6° 8' 31" W — Deployment and recovery of glider with nitrate sensor
Other physical oceanographic measurements48° 20' 27" N  9° 43' 8" W — Deployment and recovery of glider with nitrate sensor
Data held at BODC 
Series/Profiles 
33  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.
13729942014-08-04 11:21 49° 48' 47" N  5° 28' 39" W  View metadata report for BODC series reference number 1372994
13730082014-08-05 05:10 49° 23' 10" N  8° 37' 7" W  View metadata report for BODC series reference number 1373008
13730212014-08-05 11:03 49° 22' 59" N  8° 36' 42" W  View metadata report for BODC series reference number 1373021
13730332014-08-05 16:10 49° 22' 18" N  8° 36' 28" W  View metadata report for BODC series reference number 1373033
13730452014-08-06 08:23 48° 20' 17" N  9° 43' 37" W  View metadata report for BODC series reference number 1373045
13730572014-08-07 06:04 48° 34' 12" N  9° 30' 35" W  View metadata report for BODC series reference number 1373057
13730692014-08-07 11:10 48° 34' 34" N  9° 30' 58" W  View metadata report for BODC series reference number 1373069
13730702014-08-07 15:00 48° 34' 18" N  9° 30' 18" W  View metadata report for BODC series reference number 1373070
13730822014-08-08 11:05 50° 15' 28" N  7° 44' 37" W  View metadata report for BODC series reference number 1373082
13730942014-08-09 06:08 51° 8' 15" N  6° 35' 9" W  View metadata report for BODC series reference number 1373094
13731012014-08-09 10:40 51° 7' 14" N  6° 37' 18" W  View metadata report for BODC series reference number 1373101
13731132014-08-09 13:30 51° 7' 5" N  6° 37' 31" W  View metadata report for BODC series reference number 1373113
13731252014-08-09 16:04 51° 7' 5" N  6° 37' 31" W  View metadata report for BODC series reference number 1373125
13731372014-08-10 06:58 51° 9' 25" N  6° 34' 16" W  View metadata report for BODC series reference number 1373137
13731492014-08-10 08:00 51° 9' 22" N  6° 34' 31" W  View metadata report for BODC series reference number 1373149
13731502014-08-10 08:59 51° 9' 20" N  6° 34' 38" W  View metadata report for BODC series reference number 1373150
13731622014-08-10 10:00 51° 9' 10" N  6° 35' 22" W  View metadata report for BODC series reference number 1373162
13731742014-08-10 11:03 51° 8' 58" N  6° 35' 54" W  View metadata report for BODC series reference number 1373174
13731862014-08-10 12:04 51° 8' 51" N  6° 36' 11" W  View metadata report for BODC series reference number 1373186
13731982014-08-10 12:59 51° 8' 48" N  6° 36' 19" W  View metadata report for BODC series reference number 1373198
13732052014-08-10 13:59 51° 8' 44" N  6° 36' 24" W  View metadata report for BODC series reference number 1373205
13732172014-08-10 15:08 51° 8' 44" N  6° 36' 24" W  View metadata report for BODC series reference number 1373217
13732292014-08-10 16:10 51° 8' 44" N  6° 36' 19" W  View metadata report for BODC series reference number 1373229
13732302014-08-10 17:00 51° 8' 44" N  6° 36' 15" W  View metadata report for BODC series reference number 1373230
13732422014-08-10 17:57 51° 8' 44" N  6° 36' 15" W  View metadata report for BODC series reference number 1373242
13732542014-08-10 19:06 51° 8' 44" N  6° 36' 15" W  View metadata report for BODC series reference number 1373254
13732662014-08-11 10:58 51° 12' 42" N  6° 8' 30" W  View metadata report for BODC series reference number 1373266
13732782014-08-11 14:01 51° 12' 19" N  6° 8' 30" W  View metadata report for BODC series reference number 1373278
13732912014-08-12 07:00 51° 8' 54" N  6° 36' 15" W  View metadata report for BODC series reference number 1373291
13733092014-08-12 11:00 51° 8' 23" N  6° 37' 19" W  View metadata report for BODC series reference number 1373309
13733102014-08-12 13:26 51° 8' 13" N  6° 37' 46" W  View metadata report for BODC series reference number 1373310
13733222014-08-12 18:00 51° 8' 5" N  6° 37' 59" W  View metadata report for BODC series reference number 1373322
13733342014-08-13 11:00 51° 12' 34" N  6° 3' 21" W  View metadata report for BODC series reference number 1373334
Discrete samples 
30  CTD frame plus rosette samplerAmmonium and ammonia concentration parameters 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