RRS Discovery D203A
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS Discovery (74E3) |
| Cruise identifier | D203A |
| Cruise period | 1993-07-02 — 1993-07-15 |
| Status | Completed |
| Port of departure | Gibraltar, Gibraltar |
| Port of return | Nice, France |
| Purpose | Research |
| Objectives | 1) To investigate the exchange fluxes of nutrients, trace metals, and organic matter between the Western Mediterranean basin and Atlantic at the Straits of Gibraltar, and with the Eastern Mediterranean along the Straits of Sicily
2) The concentrations and speciations of dissolved metals include: Fe, Ni, Co, Cd, Pb, Zn, Cu, Al, were determined from surface to deep (2660 m) waters along a track from Gibraltar to Sicily. The particulate from these metals were sampled using the Stand Alone Pumps (SAPS). 3) The distribution of nutrients (nitrite, nitrate, silicate, ammonium, phosphate) were determined at their nanomolar levels in order to map the severe biological depletion in these oligotrophic waters. 4) An undulating oceanographic recorder (UOR) was towed between all stations to obtain upper ocean sections of salinity, temperature, fluorescence and bio-optics. 5) The photosynthetic status (production rates, nutrient limitation, light limitation, etc) of the phytoplankton was assessed using a novel US submersible Fast Flash Fluorometer |
| Chief scientist | R Fauzi C Mantoura (Plymouth Marine Laboratory) |
| Project | EROS 2000 MAST |
| Coordinating body | DG XII, European Community, Environment Programme |
| Cruise report |  (11.93 MB) |
| Ocean/sea areas | |
| General | Mediterranean Sea - Western basin |
| Specific | West and north west Mediterranean Sea, Gibraltar Straits, Sicily Straits, Gulf du Lions |
| Track charts | (0.07 MB) |
| Measurements | |
| Physical oceanography | |
| CTD stations | Quantity: number of profiles = 46 Description: CTD frame with fluorometer, transmissometer and light meters |
| Subsurface temperature and salinity measurements | Quantity: number of deployments = 50 Description: UOR tows |
| Transparency (eg transmissometer) | Quantity: number of profiles = 46 Description: CTD frame with fluorometer, transmissometer and light meters |
| Optics (eg underwater light levels) | Quantity: number of deployments = 50 Description: UOR tows |
| Optics (eg underwater light levels) | Quantity: number of profiles = 46 Description: CTD frame with fluorometer, transmissometer and light meters |
| Chemical oceanography | |
| Oxygen | Quantity: number of profiles = 46 Description: CTD frame with fluorometer, transmissometer and light meters |
| Other dissolved gases | Quantity: number of samples = 31 Description: analysis of 26 H2O2 & 5 Methylammonia samples |
| Phosphate | Quantity: number of profiles = 26 Description: 12 depths |
| Phosphate | Quantity: number of measurements = 24 Description: nutrient structures for inflow and export of water |
| Nitrate | Quantity: number of measurements = 24 Description: nutrient structures for inflow and export of water |
| Nitrate | Quantity: number of profiles = 26 Description: 12 depths |
| Nitrite | Quantity: number of measurements = 24 Description: nutrient structures for inflow and export of water |
| Nitrite | Quantity: number of profiles = 26 Description: 12 depths |
| Ammonia | Quantity: number of measurements = 24 Description: nutrient structures for inflow and export of water |
| Silicate | Quantity: number of profiles = 26 Description: 12 depths |
| Silicate | Quantity: number of measurements = 24 Description: nutrient structures for inflow and export of water |
| Other chemical oceanographic measurements | Quantity: number of samples = 160 Description: unfiltered seawater (100-150ml), distribution of organic fluorophores |
| Contamination | |
| Suspended matter | Quantity: number of stations = 17 Description: deep pumping of particles - 60 samples |
| Trace metals | Quantity: number of stations = 13 Description: trace metal fluxes |
| Trace metals | Quantity: number of stations = 8 Description: electroactive trace metals |
| Trace metals | Description: Trace metal speciation |
| Biology and fisheries | |
| Primary productivity | Quantity: number of experiments = 2 Description: fluorescence used to assess primary productivity in two methods |
| Primary productivity | Quantity: number of samples = 40 Description: production |
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of profiles = 46 Description: CTD frame with fluorometer, transmissometer and light meters |
| Dissolved organic matter (inc DOC) | Quantity: number of samples = 40 Description: DOC |
| Moorings, landers, buoys | |
| Biology and fisheries | |
| Primary productivity | 42° 10' 0" N 5° 22' 0" E — prim. prod. in situ rig, 6 depths to 95m, 24 Jul, 14C, 15N, O2 |
| Primary productivity | 43° 47' 59" N 3° 43' 59" E — prim. prod. in situ rig, 6 depths to 95m, 14C, 15N, O2 |
| Primary productivity | 40° 58' 59" N 6° 1' 59" E — prim. prod. in situ rig, 6 depths to 95m, 18 Jul, 14C, 15N, O2 |
| Primary productivity | 40° 45' 0" N 6° 4' 59" E — prim. prod. in situ rig, 6 depths to 95m, 20 Jul, 14C, 15N, O2 |
| Primary productivity | 43° 17' 59" N 4° 49' 0" E — prim. prod. in situ rig, 6 depths to 95m, 22 Jul, 14C, 15N, O2 |
| Primary productivity | 42° 43' 59" N 5° 4' 59" E — prim. prod. in situ rig, 6 depths to 95m, 26 Jul, 14C, 15N, O2 |
| Primary productivity | 43° 6' 0" N 4° 55' 59" E — prim. prod. in situ rig, 6 depths to 95m, 28 Jul, 14C, 15N, O2 |
| Sediment traps | 43° 47' 59" N 3° 43' 59" E — sediment trap, 3 Jul 1993 |
| Sediment traps | 41° 0' 0" N 6° 0' 0" E — sediment trap, 18 Jul 1993 |
| Data held at BODC | |
| Discrete samples | |
| 46 CTD frame plus rosette sampler | Transmittance and attenuance of the water column Dissolved oxygen parameters in the water column Salinity of the water column Temperature of the water column Visible waveband radiance and irradiance measurements in the water column Raw light meter output Density of the water column Raw fluorometer output Chlorophyll pigment concentrations in water bodies |
