Resources

RRS Discovery D357 (GA10)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74E3)
Cruise identifierD357 (GA10)
Cruise period2010-10-18 — 2010-11-22
StatusCompleted
Port of departureCape Town, South Africa
Port of returnCape Town, South Africa
PurposeResearch
ObjectivesThe three major questions we aim to answer are:

1. A prominent region of high productivity occurs at 40oS in the Atlantic in an ocean basin with low concentrations of micronutrients such as Fe. How are micronutrients supplied to support the productivity in this region, and how does this supply influence the nature of the ecosystem across the basin?

2. Deep-water masses in the South Atlantic upwell to the south and north to supply micronutrients to the Fe-starved Southern Ocean, and to the highly productive Equatorial Atlantic. Which processes control the concentration and distribution of micronutrients in deep waters in the South Atlantic, and therefore ultimately the supply of micronutrients to these surface systems?

3. The sources, sinks, and internal cycling of micronutrients in the global ocean remains poorly understood. What are the fluxes of micronutrients in the global ocean, and what are the dominant processes that control these fluxes?
Chief scientistGideon Henderson (University of Oxford Department of Earth Sciences)
ProjectGEOTRACES
Coordinating bodyNatural Environment Research Council (NERC)
Cruise reportRRS Discovery D357 (GA10) cruise report d357.pdf (7.13 MB) 
Ocean/sea areas 
GeneralSouth East Atlantic Ocean (limit 20W)
Track chartsRRS Discovery D357 (GA10) cruise track — d357trk.pdf (0.16 MB) 
Measurements 
Physical oceanography 
Water bottle stationsDescription: CTD casts - 24 bottle carousel
CTD stationsQuantity: number of profiles = 24
Description: Seabird 911 plus Profiling stainless steel CTD; temperaturex2, conductivityx2, pressure, dissolved oxygen, fluorometer, transmissometer, LADCP, altimeter, pinger
CTD stationsQuantity: number of profiles = 22
Description: Seabird 911 plus Profiling titanium CTD; temperaturex2, conductivityx2, pressure, dissolved oxygen, fluorometer, altimeter, backscatter, transmissometer
Subsurface temperature and salinity measurementsDescription: Ship fitted underway data (surface temperature, sainity, fluorescence and transmissivity). Ship fitted meterological instruments (wind speed/direction, Incident light, PAR etc)
Subsurface temperature and salinity measurementsQuantity: number of samples = 750
Description: Salinity
Geochemical tracers (eg freons)Quantity: number of samples = 150
Description: Dissolved Noble gases/3He and H
Current profiler (eg ADCP)Description: Vessel mounted ADCP
Other physical oceanographic measurementsQuantity: number of profiles = 67
Description: Vertical turbulence profiler
Chemical oceanography 
OxygenQuantity: number of samples = 365
Description: Winkler titrations for calibrating the CTD DO sensors
Carbon dioxideQuantity: number of samples = 70
Description: Underway DOC/DIC/TDN/Alkalinity samples were taken from the non-toxic seawater supply (intake at ~5m depth)
Carbon dioxideQuantity: number of samples = 300
Description: Profiles of DOC/DIC/TDN /Alkalinity were sampled from the Titanium and Stainless Steel CTDs in 250ml borosilicate bottles.
Other dissolved gasesQuantity: number of samples = 103
Description: Dissolved and Particulate 231Pa/230Th analysed using MC-ICP-MS
PhosphateQuantity: number of samples = 854
Description: Discrete water samples collected from CTD bottles to determine inorganic nutrient concentration. Analysed with segmented flow autoanalyser and colourimetric detection.
NitrateQuantity: number of samples = 854
Description: Discrete water samples collected from CTD bottles to determine inorganic nutrient concentration. Analysed with segmented flow autoanalyser and colourimetric detection.
AmmoniaQuantity: number of samples = 854
Description: Discrete water samples collected from CTD bottles to determine inorganic nutrient concentration. Analysed with segmented flow autoanalyser and colourimetric detection.
SilicateQuantity: number of samples = 854
Description: Discrete water samples collected from CTD bottles to determine inorganic nutrient concentration. Analysed with segmented flow autoanalyser and colourimetric detection.
AlkalinityQuantity: number of samples = 70
Description: Underway DOC/DIC/TDN/Alkalinity samples were taken from the non-toxic seawater supply (intake at ~5m depth)
AlkalinityQuantity: number of samples = 300
Description: Profiles of DOC/DIC/TDN /Alkalinity were sampled from the Titanium and Stainless Steel CTDs in 250ml borosilicate bottles.
Trace elementsQuantity: number of samples = 259
Description: Particular trace metals from OTE bottles to be analysed by ICP-MS on shore at Plymouth University
Trace elementsQuantity: number of stations = 15
Description: Dissolved Rare earth elements (REE) to be analysed at Oxford by ICP_MS
Trace elementsDescription: Dissolved Cd concentrations and isotopes
Trace elementsQuantity: number of samples = 247
Description: Total dissolvable metal to be analysed by ICP-MS on shore at NOC
Trace elementsQuantity: number of samples = 118
Description: Total dissolvable, Dissolved (<0.2 μm) Co concentrations, Ti CTD samples
Trace elementsQuantity: number of samples = 247
Description: Total dissolvable, Dissolved (<0.2 μm) Zn concentrations, Ti CTD samples
Trace elementsQuantity: number of samples = 60
Description: Total dissolvable, Dissolved (<0.2 μm) Al concentrations, underway samples
Trace elementsQuantity: number of samples = 271
Description: Total dissolvable, Dissolved (<0.2 μm) Al concentrations, Ti CTD samples
Trace elementsQuantity: number of samples = 271
Description: Total dissolvable, Dissolved (<0.2 μm) Fe concentrations, and Fe speciation, Ti CTD samples
Trace elementsQuantity: number of samples = 60
Description: Total dissolvable, Dissolved (<0.2 μm) Fe concentrations, underway samples
Trace elementsQuantity: number of stations = 9
Description: SAPS (Stand Alone in-situ Pumping System) was used to collect particulate metals, biomarkers and Th234
Trace elementsQuantity: number of stations = 22
Description: The ocean mercury cycle, Total dissolved Hg, dissolved gases Hg, Total Hg samples collected from both rosetts, underway fish
Trace elementsQuantity: number of samples = 15
Description: Particulate aerosol sampled collected on filters using high volume collector on ship
Trace elementsQuantity: number of samples = 2
Description: Rainwater samples collected using funnel on ship
RadioactivityQuantity: number of samples = 74
Description: Th234 samples from rosette, Beta radioactivity on verticale profiles
RadioactivityQuantity: number of samples = 22
Description: Total Pu and Np concentration patterns referred to as Anthropogenic radionuclides
IsotopesDescription: Dissolved Cd concentrations and isotopes
IsotopesQuantity: number of stations = 22
Description: Nitrate 15N and 18O
IsotopesQuantity: number of samples = 48
Description: Si isotopes
IsotopesQuantity: number of samples = 94
Description: 13C OF DIC
IsotopesQuantity: number of samples = 103
Description: Dissolved Nd isotopes
IsotopesQuantity: number of stations = 4
Description: Dissolved Pb, isotopes and Dissolved Pb concentration
IsotopesQuantity: number of samples = 15
Description: Metal isotopes in Aerosol (Pb, Nd, Sr, Zn, and Cd isotopes)
IsotopesQuantity: number of samples = 100
Description: Particulate d15N and POC, PON isotopes
IsotopesQuantity: number of stations = 4
Description: Ge, Ni, Cr, TI, V isotopes
IsotopesQuantity: number of stations = 4
Description: Fe isotopes
IsotopesQuantity: number of stations = 4
Description: Zn and Cu isotopes
IsotopesQuantity: number of samples = 10
Description: 227Ac and 223,224,226,228Ra in deep waters (Isotopes and concentration) using SAPS
IsotopesQuantity: number of samples = 32
Description: 223,224Ra and Ac in surface waters
IsotopesQuantity: number of samples = 230
Description: Oxygen Isotopes
Other chemical oceanographic measurementsQuantity: number of samples = 8
Description: Pore water chemistry
Other chemical oceanographic measurementsQuantity: number of samples = 120
Description: Dissolved Barium will be analaysed at the University of Edinburgh
Other chemical oceanographic measurementsQuantity: number of samples = 49
Description: Metal speciation and Ligands (Fe, Zn, Co) Ti CTD samples to be analysed on shore using CLE-AdSV
Other chemical oceanographic measurementsQuantity: number of stations = 9
Description: SAPS (Stand Alone in-situ Pumping System) was used to collect particulate metals, biomarkers and Th234
Biology and fisheries 
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of samples = 150
Phytoplankton pigs (eg chlorophyll, fluorescence)Quantity: number of samples = 100
Description: HPLC. Analysis for pigments to be analysed at Oxford
Particulate organic matter (inc POC, PON)Quantity: number of samples = 100
Description: Particulate d15N and POC, PON isotopes
Biochemical measurements (eg lipids, amino acids)Quantity: number of samples = 50
Description: DNA and RNA. To be analysed at IFM-GEOMAR
Biochemical measurements (eg lipids, amino acids)Quantity: number of stations = 9
Description: SAPS (Stand Alone in-situ Pumping System) was used to collect particulate metals, biomarkers and Th234
Biochemical measurements (eg lipids, amino acids)Quantity: number of samples = 150
Description: Intact Polar Lipids (IPL) and Biomarkers
PhytoplanktonQuantity: number of samples = 150
Description: ANALYSIS OF PHYTOPLANKTON COMMUNITY STRUCTURE using flow cytometry
Pelagic bacteria/micro-organismsQuantity: number of samples = 78
Description: FAST REPITITION RATE FLUOROMETRY (FRRF) depth profiles collected from the standard CTD
Pelagic bacteria/micro-organismsQuantity: number of samples = 36
Description: Underway FRRF samples were taken from the non-toxic seawater supply (intake at ~5m depth)
Other biological/fisheries measurementQuantity: number of samples = 60
Description: Flow cytometry and qPCR analysis of marine picocynaobacteria. To be analysed at MIT
Other biological/fisheries measurementDescription: CDOM
Meteorology 
Routine standard measurementsDescription: Ship fitted underway data (surface temperature, sainity, fluorescence and transmissivity). Ship fitted meterological instruments (wind speed/direction, Incident light, PAR etc)
Geology and geophysics 
Core - soft bottomQuantity: number of stations = 7
Description: Sediment core samples collected using a multicore or a box core
Data held at BODC Get data
Discrete samples 
77  All plastic clean surface pumped supplyDissolved metal concentrations in the water column
Radioactivity in water bodies
Chlorophyll pigment concentrations in water bodies
Carotenoid and flavenoid pigment concentrations in water bodies
15  Atmospheric air sampling pumpMetal concentrations in the atmosphere
Atmospheric particulates
Concentration of nitrogen species in the atmosphere
Concentration of inorganic halogens in the atmosphere
Sulphur species concentrations in the atmosphere
Stable isotopes in the atmosphere
25  CTD frame plus rosette samplerDissolved total and organic nitrogen concentrations in the water column
Dissolved metal concentrations in the water column
Density of the water column
Visible waveband radiance and irradiance measurements in the water column
Radioactivity in water bodies
Transmittance and attenuance of the water column
Stable isotopes in water bodies
Electrical conductivity of the water column
Chlorophyll pigment concentrations in water bodies
Silicate concentration parameters in the water column
Alkalinity, acidity and pH of the water column
Salinity of the water column
Dissolved organic carbon concentration in the water column
Raw oxygen sensor output
Total dissolved inorganic carbon (TCO2) concentration in the water column
Temperature of the water column
Carotenoid and flavenoid pigment concentrations in water bodies
Nitrate concentration parameters in the water column
Optical backscatter
Phosphate concentration parameters in the water column
Dissolved oxygen parameters in the water column
Nitrite concentration parameters in the water column
4  Rain water collectorPrecipitation chemistry
6  Stand-alone pumpsRadioactivity in water bodies
21  Dissolved metal concentrations in the water column
Particulate metal concentrations in the water column
Density of the water column
Radioactivity in water bodies
Transmittance and attenuance of the water column
Particulate total and organic phosphorus concentrations in the water column
Stable isotopes in water bodies
Electrical conductivity of the water column
Chlorophyll pigment concentrations in water bodies
Silicate concentration parameters in the water column
Salinity of the water column
Raw oxygen sensor output
Temperature of the water column
Nitrate concentration parameters in the water column
Optical backscatter
Phosphate concentration parameters in the water column
Dissolved oxygen parameters in the water column
Nitrite concentration parameters in the water column