Resources

RRS Discovery DY081

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74EQ)
Cruise identifierDY081
Cruise period2017-07-05 — 2017-08-08
StatusCompleted
Port of departureSt. John's, Canada
Port of returnSouthampton, United Kingdom
PurposeResearch
ObjectivesThe high-latitude regions are experiencing some of the most rapid changes observed in recent decades. Arctic temperatures are rising twice as fast as the global mean, Greenland's glaciers are experiencing significant mass loss, multi-year Arctic sea-ice is declining, and the Nordic Seas are warming at an accelerated rate. These processes are important locally, but their effects are likely to have a global impact: for example, the North Atlantic receives freshwater from the Arctic, Greenland and Canada and is a formation locus of the deep-water masses, which represent a major component of ocean circulation that drives global heat and nutrient fluxes. Concurrently to the recently observed changes in ice dynamics and accessibility, there has been a significant increase in commercial interest of the natural resources in the ecosystems of the Arctic, surrounding seas and high-latitude North Atlantic. An understanding how natural resources - including fisheries, bird and mammal stocks that are essential for food and tourism - will respond in the future to increasing anthropogenic stress on a regional and global scale relies on an understanding of marine biogeochemistry and the sources and sinks of essential nutrients. The overall aim of ICY-LAB is to understand nutrient and isotope cycling in the climatically critical but understudied regions of the Labrador Sea and Greenland fjords, and the impact of cryosphere, biosphere and hydrosphere on the biogeochemistry of the region and the global oceans. The approach of ICY-LAB will be to capture the whole biogeochemical system in areas of marked environmental change using careful field sampling strategies, with research expeditions to coastal Greenland and the open ocean Labrador Sea. DY081 represents the key oceanic component of this sampling campaign, focusing on the influence of meltwater on nutrient cycling in the Labrador Sea.
Chief scientistKatharine R Hendry (University of Bristol School of Earth Sciences)
ProjectICY-LAB: Isotope Cycling In The Labrador Sea
Coordinating bodyEuropean Research Council (ERC)
Cruise reportRRS Discovery DY081 cruise report dy081.pdf (8.90 MB) 
Ocean/sea areas 
GeneralLabrador Sea (Davis Strait)
SpecificOrphan Knoll, Southwest Greenland.
Track chartsRRS Discovery DY081 cruise track — dy081trk.pdf (1.30 MB) 
Measurements 
Physical oceanography 
CTD stationsQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Optics (eg underwater light levels)Quantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Geochemical tracers (eg freons)Quantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Current metersQuantity: activity duration in days = 35
Description: HULL MOUNTED ADCP. Teledyne OS075 ADCP and Teledyne OS150 ADCP.
Current profiler (eg ADCP)Quantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Current profiler (eg ADCP)Quantity: activity duration in days = 35
Description: HULL MOUNTED ADCP. Teledyne OS075 ADCP and Teledyne OS150 ADCP.
Chemical oceanography 
OxygenQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
PhosphateQuantity: number of samples = 66
Description: WATER BOTTLES COLLECTED BY REMOTELY OPERATED VEHICLE. Discrete water samples taken for nutrients and their isotopes. All analyses will be carried out on shore. The samples were taken for biogeochemical investigations.
PhosphateQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
PhosphateQuantity: activity duration in days = 22
Description: UNDERWAY TOWFISH WATER SAMPLING. Discrete water samples taken (near surface) for nutrients, trace metals, trace metal isotopes. Radium isotope samples processed on board, other isotope systems will be processed on shore to determine hydrographic and biogeochemical cycling regime of the study locations.
NitrateQuantity: activity duration in days = 22
Description: UNDERWAY TOWFISH WATER SAMPLING. Discrete water samples taken (near surface) for nutrients, trace metals, trace metal isotopes. Radium isotope samples processed on board, other isotope systems will be processed on shore to determine hydrographic and biogeochemical cycling regime of the study locations.
NitrateQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
NitrateQuantity: number of samples = 66
Description: WATER BOTTLES COLLECTED BY REMOTELY OPERATED VEHICLE. Discrete water samples taken for nutrients and their isotopes. All analyses will be carried out on shore. The samples were taken for biogeochemical investigations.
NitriteQuantity: number of samples = 66
Description: WATER BOTTLES COLLECTED BY REMOTELY OPERATED VEHICLE. Discrete water samples taken for nutrients and their isotopes. All analyses will be carried out on shore. The samples were taken for biogeochemical investigations.
NitriteQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
NitriteQuantity: activity duration in days = 22
Description: UNDERWAY TOWFISH WATER SAMPLING. Discrete water samples taken (near surface) for nutrients, trace metals, trace metal isotopes. Radium isotope samples processed on board, other isotope systems will be processed on shore to determine hydrographic and biogeochemical cycling regime of the study locations.
SilicateQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
AlkalinityQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Trace elementsQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Trace elementsQuantity: activity duration in days = 22
Description: UNDERWAY TOWFISH WATER SAMPLING. Discrete water samples taken (near surface) for nutrients, trace metals, trace metal isotopes. Radium isotope samples processed on board, other isotope systems will be processed on shore to determine hydrographic and biogeochemical cycling regime of the study locations.
Trace elementsQuantity: number of samples = 66
Description: WATER BOTTLES COLLECTED BY REMOTELY OPERATED VEHICLE. Discrete water samples taken for nutrients and their isotopes. All analyses will be carried out on shore. The samples were taken for biogeochemical investigations.
RadioactivityQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
IsotopesQuantity: activity duration in days = 22
Description: UNDERWAY TOWFISH WATER SAMPLING. Discrete water samples taken (near surface) for nutrients, trace metals, trace metal isotopes. Radium isotope samples processed on board, other isotope systems will be processed on shore to determine hydrographic and biogeochemical cycling regime of the study locations.
IsotopesQuantity: number of samples = 66
Description: WATER BOTTLES COLLECTED BY REMOTELY OPERATED VEHICLE. Discrete water samples taken for nutrients and their isotopes. All analyses will be carried out on shore. The samples were taken for biogeochemical investigations.
IsotopesQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Other chemical oceanographic measurementsQuantity: number of samples = 23
Description: STAND ALONE PUMP DEPLOYMENTS. Pancake filters housings were fitted with either plastic or glass-fibre filters for biogenic silica and trace metal analysis, and organic geochemistry respectively. Pumps were lowered to between 200-2400 m. Pumps were on for 1.5 hours before recovery. All saSmples will be analysed on shore. Samples were taken for biogeochemical investigations.
Contamination 
Other contaminant measurementsQuantity: number of cores = 52
Description: MEGACORES. Sediment cores ranging from 10-40 cm long in water depths of 500 to 3700 m. Cores were: 1) Sectioned on board. Samples will be sent to University of Bristol and Lamont-Doherty Earth Observatory, Columbia University (USA). The sediments were taken for biogeochemical and palaeoceanographic investigations. Sediments will be analysed for e.g. amorphous silica, foraminiferal stable isotopes, radiocarbon and lead-201 dating, analysis of ice core debris, diatom assemblages and isotopes, and organic geochemistry. Sediments will analysed for plastic debris; 2) Sampled for porefluids on board. Porefluids were extracted for nutrients and nutrient isotopes. All analyses will be carried out on shore. The porefluids were taken for biogeochmeical investigations; 3) Used for core incubation experiments on board. Core top waters were taken at time intervals for for nutrients and nutrient isotopes. All analyses will be carried out on shore. The porefluids were taken for biogeochmeical investigations.
Other contaminant measurementsQuantity: number of cores = 90
Description: PUSH CORES COLLECTED BY REMOTELY OPERATED VEHICLE. Sediment cores ranging from 5 to 30 cm. Cores were: 1) Sectioned on board. Samples will be sent to University of Bristol and Lamont-Doherty Earth Observatory, Columbia University (USA). The sediments were taken for biogeochemical and palaeoceanographic investigations. Sediments will be analysed for e.g. amorphous silica, foraminiferal stable isotopes, radiocarbon and lead-201 dating, analysis of ice core debris, diatom assemblages and isotopes, and organic geochemistry. Sediments will analysed for plastic debris. 2) Sampled for porefluids on board. Porefluids were extracted for nutrients and nutrient isotopes. All analyses will be carried out on shore. The porefluids were taken for biogeochmeical investigations.
Biology and fisheries 
Primary productivityQuantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Particulate organic matter (inc POC, PON)Quantity: number of profiles = 24
Description: Vertical profiles (from 50-3800m) for 1) continuous reading physical measurements: pressure, temperature, conductivity, fluorescence, backscatter, oxygen, currents (LADCP); 2) discrete water samples: oxygen, carbonate chemistry*, natural radiocarbon*, nutrients*, pigments, trace elements and isotopes*, oxygen isotopes*, POC/PON*, biogenic silica*. Samples also taken for silicon-32 uptake incubations. *On shore analyses, to determine hydrographic and biogeochemical cycling regime of the study locations.
Particulate organic matter (inc POC, PON)Quantity: number of samples = 23
Description: STAND ALONE PUMP DEPLOYMENTS. Pancake filters housings were fitted with either plastic or glass-fibre filters for biogenic silica and trace metal analysis, and organic geochemistry respectively. Pumps were lowered to between 200-2400 m. Pumps were on for 1.5 hours before recovery. All saSmples will be analysed on shore. Samples were taken for biogeochemical investigations.
Benthic bacteria/micro-organismsQuantity: number of specimens = 1116
Description: BIOLOGY COLLECTED BY REMOTELY OPERATED VEHICLE. Zoobenthos were collected for taxonomic, genetics, microbial and geochemical investigations.
ZoobenthosQuantity: number of specimens = 1116
Description: BIOLOGY COLLECTED BY REMOTELY OPERATED VEHICLE. Zoobenthos were collected for taxonomic, genetics, microbial and geochemical investigations.
MolluscsQuantity: number of specimens = 1116
Description: BIOLOGY COLLECTED BY REMOTELY OPERATED VEHICLE. Zoobenthos were collected for taxonomic, genetics, microbial and geochemical investigations.
CrustaceansQuantity: number of specimens = 1116
Description: BIOLOGY COLLECTED BY REMOTELY OPERATED VEHICLE. Zoobenthos were collected for taxonomic, genetics, microbial and geochemical investigations.
Geology and geophysics 
Core - soft bottomQuantity: number of cores = 52
Description: MEGACORES. Sediment cores ranging from 10-40 cm long in water depths of 500 to 3700 m. Cores were: 1) Sectioned on board. Samples will be sent to University of Bristol and Lamont-Doherty Earth Observatory, Columbia University (USA). The sediments were taken for biogeochemical and palaeoceanographic investigations. Sediments will be analysed for e.g. amorphous silica, foraminiferal stable isotopes, radiocarbon and lead-201 dating, analysis of ice core debris, diatom assemblages and isotopes, and organic geochemistry. Sediments will analysed for plastic debris; 2) Sampled for porefluids on board. Porefluids were extracted for nutrients and nutrient isotopes. All analyses will be carried out on shore. The porefluids were taken for biogeochmeical investigations; 3) Used for core incubation experiments on board. Core top waters were taken at time intervals for for nutrients and nutrient isotopes. All analyses will be carried out on shore. The porefluids were taken for biogeochmeical investigations.
Core - soft bottomQuantity: number of cores = 5
Description: GRAVITY CORES. Sediment cores ranging from 0.82 to 5.15 m long in water depths of 1600 to 3700 m. Split and sectioned on board. Archive halves will be kept at BOSCORF; sampled halves will be sent to University of Bristol and Lamont-Doherty Earth Observatory, Columbia University (USA). The sediments were taken for palaeoceanographic investigations. Sediments will be analysed for e.g. foraminiferal stable isotopes, radiocarbon dating, analysis of ice core debris, diatom assemblages and isotopes and organic geochemistry.
Core - soft bottomQuantity: number of cores = 90
Description: PUSH CORES COLLECTED BY REMOTELY OPERATED VEHICLE. Sediment cores ranging from 5 to 30 cm. Cores were: 1) Sectioned on board. Samples will be sent to University of Bristol and Lamont-Doherty Earth Observatory, Columbia University (USA). The sediments were taken for biogeochemical and palaeoceanographic investigations. Sediments will be analysed for e.g. amorphous silica, foraminiferal stable isotopes, radiocarbon and lead-201 dating, analysis of ice core debris, diatom assemblages and isotopes, and organic geochemistry. Sediments will analysed for plastic debris. 2) Sampled for porefluids on board. Porefluids were extracted for nutrients and nutrient isotopes. All analyses will be carried out on shore. The porefluids were taken for biogeochmeical investigations.
Bottom photographyQuantity: activity duration in days = 2
Description: Photogrammatry and multibeam reson surveys by remotely operated vehicle.
In-situ seafloor measurement/samplingQuantity: number of cores = 90
Description: PUSH CORES COLLECTED BY REMOTELY OPERATED VEHICLE. Sediment cores ranging from 5 to 30 cm. Cores were: 1) Sectioned on board. Samples will be sent to University of Bristol and Lamont-Doherty Earth Observatory, Columbia University (USA). The sediments were taken for biogeochemical and palaeoceanographic investigations. Sediments will be analysed for e.g. amorphous silica, foraminiferal stable isotopes, radiocarbon and lead-201 dating, analysis of ice core debris, diatom assemblages and isotopes, and organic geochemistry. Sediments will analysed for plastic debris. 2) Sampled for porefluids on board. Porefluids were extracted for nutrients and nutrient isotopes. All analyses will be carried out on shore. The porefluids were taken for biogeochmeical investigations.
Single-beam echosoundingQuantity: activity duration in days = 35
Description: SINGLE BEAM ACOUSTICS. An EK60 profiler was used to determine the nature of the water column. A sub-bottom profiler SBP120 was used to determine the nature of the seafloor for identification of coring sites. Acoustics recorded in study region and on transit back to UK.
Multi-beam echosoundingQuantity: activity duration in days = 35
Description: MULTIBEAM ACOUSTICS. EM122, EM720 and Reson 7125 multibeam echosounder systems were used to map the bathymetry of the seafloor. Acoustics recorded in study region and on transit back to UK.
Multi-beam echosoundingQuantity: activity duration in days = 2
Description: Photogrammatry and multibeam reson surveys by remotely operated vehicle.
Moorings, landers, buoys 
Physical oceanography 
CTD stations62° 53' 59" N  52° 37' 59" W — Two Slocum gliders (units 331 and 439) deployed to measure pressure, temperature, conductivity, fluorescense, backscatter at highest resolution; diving from surface to 1000m; deployed on 17/07/2017 and recovered 24/07/2017 at Nuuk site.
Subsurface temperature and salinity measurements62° 53' 59" N  52° 37' 59" W — Two Slocum gliders (units 331 and 439) deployed to measure pressure, temperature, conductivity, fluorescense, backscatter at highest resolution; diving from surface to 1000m; deployed on 17/07/2017 and recovered 24/07/2017 at Nuuk site.
Optics (eg underwater light levels)62° 53' 59" N  52° 37' 59" W — Two Slocum gliders (units 331 and 439) deployed to measure pressure, temperature, conductivity, fluorescense, backscatter at highest resolution; diving from surface to 1000m; deployed on 17/07/2017 and recovered 24/07/2017 at Nuuk site.
Current meters62° 53' 59" N  52° 37' 59" W — Two Slocum gliders (units 331 and 439) deployed to measure pressure, temperature, conductivity, fluorescense, backscatter at highest resolution; diving from surface to 1000m; deployed on 17/07/2017 and recovered 24/07/2017 at Nuuk site.