Resources

RRS Discovery DY103

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74EQ)
Cruise identifierDY103
Cruise period2019-06-21 — 2019-07-09
StatusCompleted
Port of departureSouthampton, United Kingdom
Port of returnSouthampton, United Kingdom
PurposeResearch
ObjectivesTo study the oceanic water column and the underlying seabed change, on a variety of temporal and spatial scales. The objective of the Porcupine Abyssal Plain Sustained observatory is to provide high temporal resolution (hours) of an increasing number of variables which are relevant from the perspective of the biology, physics and chemistry over a relatively small spatial scale (30 km). The site has been under examination since 1985 and during that time, substantial changes have been observed in the benthic environment. The intention is to sustain and enhance these observations in order that a deeper understanding is obtained of the processes which operate; in particular the responses to the changes which are currently taking place in the global environment. The objective of the cruise was primarily to service the infrastructure required for continuous sustained observation, and to put these into context using observations from the ship which as yet cannot be carried out autonomously. In parallel to maintaining and extending exisiting measurements, the over view was enhanced by parallel research into the abundance and distribution of seafloor life in relation to incoming food flux. These investigations were carried out using a multi-instrument observational approach combined with direct sampling. The cruise achieved sampling of the abyssal plain seabed and its fauna via coring, trawling, and baited traps, and left in place a time-lapse camera system for extended (1-year) seafloor observation. In addition, we deployed an ADCP and sediment trap mooring in a central branch of Whittard Canyon on behalf of a partner NOC NERC-funded CLASS project component (NOC lead Drs V. Huvenne & M. Clare).
Chief scientistSusan E Hartman (National Oceanography Centre, Southampton)
ProjectPorcupine Abyssal Plain deep ocean observatory
Coordinating bodyNatural Environment Research Council (NERC)
Cruise reportRRS Discovery DY103 cruise report dy103.pdf (13.01 MB) 
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
SpecificPorcupine Abyssal Plain, Whittard Canyon.
Track chartsRRS Discovery DY103 cruise track — dy103trk.pdf (0.18 MB) 
Measurements 
Physical oceanography 
CTD stationsQuantity: number of profiles = 12
Description: CTD measurements of pressure, salinity, temperature, oxygen, chlorophyll, plus water samples from some CTDs for chlorophyll, oxygen, salinity, DIC and pH
Biology and fisheries 
Particulate organic matter (inc POC, PON)Quantity: number of stations = 4
Description: HyBIS towed camera, seafloor photography
ZooplanktonQuantity: number of stations = 6
Description: WP2, plankton net, 200 µm, to 200 m, 3 x midnight, 3 x noon
ZoobenthosQuantity: number of hauls = 2
Description: Otter trawl samples of megabenthos
ZoobenthosQuantity: number of stations = 8
Description: Megacore sediment samples for various analyses
Demersal fishQuantity: number of hauls = 2
Description: Otter trawl samples of megabenthos
MolluscsQuantity: number of hauls = 2
Description: Otter trawl samples of megabenthos
CrustaceansQuantity: number of hauls = 2
Description: Otter trawl samples of megabenthos
Moorings, landers, buoys 
Physical oceanography 
Optics (eg underwater light levels)48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Recovery
Optics (eg underwater light levels)48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Deployment
Current meters49° 1' 0" N  16° 30' 0" W — PAP3 deep-water sediment traps Recovery
Current meters48° 58' 0" N  16° 28' 0" W — PAP3 deep-water sediment traps Deployment
Current profiler (eg ADCP)48° 37' 59" N  10° 0' 0" W — ADCPs and sediment trap
Chemical oceanography 
Oxygen49° 1' 0" N  16° 30' 0" W — PAP3 deep-water sediment traps Recovery
Oxygen48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Recovery
Oxygen48° 58' 0" N  16° 28' 0" W — PAP3 deep-water sediment traps Deployment
Oxygen48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Deployment
Carbon dioxide48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Deployment
Carbon dioxide48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Recovery
Nitrate48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Deployment
Nitrate48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Recovery
pH48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Deployment
pH48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Recovery
Contamination 
Other contaminant measurements48° 37' 59" N  10° 0' 0" W — ADCPs and sediment trap
Biology and fisheries 
Primary productivity48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Recovery
Primary productivity48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Deployment
Sediment traps49° 1' 0" N  16° 30' 0" W — PAP3 deep-water sediment traps Recovery
Sediment traps48° 58' 0" N  16° 28' 0" W — PAP3 deep-water sediment traps Deployment
Sediment traps48° 37' 59" N  10° 0' 0" W — ADCPs and sediment trap
Zooplankton48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Deployment
Zooplankton48° 58' 0" N  16° 22' 0" W — PAP1 Longterm Observatory Recovery
Zoobenthos48° 57' 0" N  16° 28' 59" W — 2 x amphipod trap deployment / recovery
Zoobenthos49° 0' 0" N  16° 26' 59" W — Time-lapse camera deployment
Crustaceans48° 57' 0" N  16° 28' 59" W — 2 x amphipod trap deployment / recovery
Geology and geophysics 
Bottom photography49° 0' 0" N  16° 26' 59" W — Time-lapse camera deployment
Data held at BODC Get data
Discrete samples 
12  CTD frame plus rosette sampler