Metadata Report for BODC Series Reference Number 2079613
Metadata Summary
Problem Reports
Data Access Policy
Narrative Documents
Project Information
Data Activity or Cruise Information
Fixed Station Information
BODC Quality Flags
SeaDataNet Quality Flags
Metadata Summary
Data Description |
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Data Identifiers |
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Time Co-ordinates(UT) |
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Spatial Co-ordinates | |||||||||||||||||||||||||||||||||
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Parameters |
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Definition of BOTTFLAG | |||||||||||||||||||||||||||||||||
BOTTFLAG | Definition |
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0 | The sampling event occurred without any incident being reported to BODC. |
1 | The filter in an in-situ sampling pump physically ruptured during sample resulting in an unquantifiable loss of sampled material. |
2 | Analytical evidence (e.g. surface water salinity measured on a sample collected at depth) indicates that the water sample has been contaminated by water from depths other than the depths of sampling. |
3 | The feedback indicator on the deck unit reported that the bottle closure command had failed. General Oceanics deck units used on NERC vessels in the 80s and 90s were renowned for reporting misfires when the bottle had been closed. This flag is also suitable for when a trigger command is mistakenly sent to a bottle that has previously been fired. |
4 | During the sampling deployment the bottle was fired in an order other than incrementing rosette position. Indicative of the potential for errors in the assignment of bottle firing depth, especially with General Oceanics rosettes. |
5 | Water was reported to be escaping from the bottle as the rosette was being recovered. |
6 | The bottle seals were observed to be incorrectly seated and the bottle was only part full of water on recovery. |
7 | Either the bottle was found to contain no sample on recovery or there was no bottle fitted to the rosette position fired (but SBE35 record may exist). |
8 | There is reason to doubt the accuracy of the sampling depth associated with the sample. |
9 | The bottle air vent had not been closed prior to deployment giving rise to a risk of sample contamination through leakage. |
Definition of Rank |
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Problem Reports
No Problem Report Found in the Database
Data Access Policy
Open Data supplied by Natural Environment Research Council (NERC)
You must always use the following attribution statement to acknowledge the source of the information: "Contains data supplied by Natural Environment Research Council."
Narrative Documents
Metrohm 716 DMS Titrino titrator
The Metrohm 716 DMS Titrino is a titrator used for five basic methods of titrations. These include DET (Dynamic Equivalence-point Titration), MET (Monotonic Equivalence-point Titration), SET (end-point titration), MEAS (measuring instrument for pH, voltage and temperature) and CAL (pH calibrations) titrations.
The instrument consists of an exchange unit, magnetic swing out stirrer, display, indicator lamps, control keys and a separate keypad. Exchange units are available in brown or clear glass with light protection. The models with light protection or brown glass should be used for light sensitive reagents. The Metrohm 716 has a built-in RS232C interface for communication with a PC and printers. Optional accessories for the Metrohm 716 include Ti stands for rinsing and addition of fresh solvent, balances, analog recorders and sample changers.
Specifications
Measuring input | 2 high-impedance measuring inputs for pH, redox and ISE electrodes; 1 reference input for a separate reference electrode; 1 measuring input for polarized electrodes; 1 measuring input for temperature sensor Pt100 or Pt1000 |
Measuring range | pH value 0 ±20; Voltage 0 ±2000 mV; current 0 ±200 µA; temperature -150 + 450 °C |
Error of measurement of instrument (without sensors) at 25 °C | pH ±0.02; voltage ± 2 mV; temperature as a function of the ambient temperature <0.2 °C in the range of 0 +100 °C; pH value typical 40 µV/K; voltage temperature 0.04 °C/K |
Measuring amplifier input resistance | >1013Ohm; offset current <3x10-13 A |
Measuring amplifier deviation of offset voltage as a function of the ambient temperature | 15 µV/K |
Polarizer | Lpol: 0 ±127µA; Upol: 0±1270 mV, in 10 mV steps |
Dosification, Volume of burette cylinder | 1, 5, 10, 20 or 50 ml |
Dosification, Resolution | 10000 steps per burette cylinder |
Analog output signal | -2000 to 2000 mV |
Analog output resolution | 1 mV (12 bit) |
Nominal operational temperature | 5 to 40 °C |
Nominal operational temperature | 5 to 40 °C |
Further details can be found in the manufacturer's specification sheet.
Niskin Bottle
The Niskin bottle is a device used by oceanographers to collect subsurface seawater samples. It is a plastic bottle with caps and rubber seals at each end and is deployed with the caps held open, allowing free-flushing of the bottle as it moves through the water column.
Standard Niskin
The standard version of the bottle includes a plastic-coated metal spring or elastic cord running through the interior of the bottle that joins the two caps, and the caps are held open against the spring by plastic lanyards. When the bottle reaches the desired depth the lanyards are released by a pressure-actuated switch, command signal or messenger weight and the caps are forced shut and sealed, trapping the seawater sample.
Lever Action Niskin
The Lever Action Niskin Bottle differs from the standard version, in that the caps are held open during deployment by externally mounted stainless steel springs rather than an internal spring or cord. Lever Action Niskins are recommended for applications where a completely clear sample chamber is critical or for use in deep cold water.
Clean Sampling
A modified version of the standard Niskin bottle has been developed for clean sampling. This is teflon-coated and uses a latex cord to close the caps rather than a metal spring. The clean version of the Levered Action Niskin bottle is also teflon-coated and uses epoxy covered springs in place of the stainless steel springs. These bottles are specifically designed to minimise metal contamination when sampling trace metals.
Deployment
Bottles may be deployed singly clamped to a wire or in groups of up to 48 on a rosette. Standard bottles and Lever Action bottles have a capacity between 1.7 and 30 L. Reversing thermometers may be attached to a spring-loaded disk that rotates through 180° on bottle closure.
D381A and D381B Discrete CTD Oxygen Sampling Document
The following contains extracts from the D381A/B cruise report.
Originator's Protocol For Data Acquisition And Analysis
Water samples were collected from 21 CTD casts during cruise D381. The samples were obtained using an SBE 911plus CTD unit with 24 Niskin bottles (10 litre) fitted to the rosette. All seawater samples were drawn through silicone tubing from the Niskin bottles into clear, pre-calibrated borosilicate glass bottles. The temperature of the samples was measured using a hand-held digital thermometer. 1 mL of manganous chloride and 1 mL alkaline iodide was added to the sample bottles before inserting a glass stopper to be bottles and shaking vigorously for 30 seconds. The samples were then left for 1 hour before being shaken again and then left for a further hour.
The method used for analysis was the Winkler whole bottle titration method with spectrophotometric end point. 1 mL of dilute sulphuric acid was added to the sample bottles (280 mL of H2SO4 per 1 litre of milli-Q water) before inserting a small magnetic stirrer bar to each sample bottle whilst standing the bottles on a magnetic stirring plate to facilitate dissolution. Each bottle was titrated with sodium thiosulphate until it was clear. The volume of the titration was recorded for use in the oxygen concentration calculation.
Cast 15 and 21 were submitted to BODC without a cast end time. Therefore this has been taken as the time the last bottles were fired.
BODC Data Processing Procedures
Discrete oxygen concentration data were supplied to BODC in a single .mat file. The values were extracted and loaded into BODC's ORACLE database. No data were considered improbable, therefore no flags were added.
Parameter details of the data are displayed in the table below:
Originator's Variable | Units | Description | BODC Parameter Code | BODC Units | Comments |
---|---|---|---|---|---|
Oxygen concentration by Winkler titration | µmol per litre | Concentration of oxygen {O2 CAS 7782-44-7} per unit volume of the water body [dissolved plus reactive particulate phase] by Winkler titration | DOXYWITX | µmol per litre | - |
- | - | Concentration standard deviation of oxygen {O2 CAS 7782-44-7} per unit volume of the water body [dissolved plus reactive particulate phase] by Winkler titration | SDOXWITX | µmol per litre | - |
Data Quality Issues
In some instances the CTD casts had bottles fired whilst the CTD was moving upwards through the water column, this was done to reduce overall deployment time. For specific information, please see the cruise report.
Two CTD packages were deployed during cruise D381 as the entire CTD package was lost on cast 13 when the wire parted.
For each Niskin bottle, two oxygen samples were submitted. BODC averaged duplicate values and from the duplicate values calculated the standard deviation.
References Cited
Naveira-Garabato A.C. et al.(2012). 'Ocean Surface Mixing, Ocean Sub-mesoscale Interaction Study'. Cruise Report National Oceanography Centre, Southampton.
Project Information
Ocean Surface Mixing, Ocean Sub-mesoscale Interaction Study (OSMOSIS)
Background
The Ocean Surface Mixing, Ocean Sub-mesoscale Interaction Study (OSMOSIS) consortium was funded to deliver NERC's Ocean Surface Boundary Layer (OSBL) programme. Commencing in 2011, this multiple year study will combine traditional observational techniques, such as moorings and CTDs, with the latest autonomous sampling technologies (including ocean gliders), capable of delivering near real-time scientific measurements through the water column.
The OSMOSIS consortium aims to improve understanding of the OSBL, the interface between the atmosphere and the deeper ocean. This layer of the water column is thought to play a pivotal role in global climate and the productivity of our oceans.
OSMOSIS involves collaborations between scientists at various universities (Reading, Oxford, Bangor, Southampton and East Anglia) together with researchers at the National Oceanography Centre (NOC), Scottish Association for Marine Science (SAMS) and Plymouth Marine Laboratory (PML). In addition, there are a number of project partners linked to the consortium.
Scientific Objectives
- The primary goal of the fieldwork component of OSMOSIS is to obtain a year-long time series of the properties of the OSBL and its controlling 3D physical processes. This is achieved with an array of moorings (two nested clusters of 4 moorings, each centred around a central mooring) and gliders deployed near the Porcupine Abyssal Plain (PAP) observatory. Data obtained from this campaign will help with the understanding of these processes and subsequent development of associated parameterisations.
- OSMOSIS will attempt to create parameterisations for the processes which determine the evolving stratification and potential vorticity budgets of the OSBL.
- The overall legacy of OSMOSIS will be to develop new (physically based and observationally supported) parameterisations of processes that deepen and shoal the OSBL, and to implement and evaluate these parameterisations in a state-of-the-art global coupled climate model, facilitating improved weather and climate predictions.
Fieldwork
Three cruises are directly associated with the OSMOSIS consortium. Preliminary exploratory work in the Clyde Sea (September 2011) to hone techniques and strategies, followed by a mooring deployment and recovery cruise in the vicinity of the Porcupine Abyssal Plain (PAP) observatory (in late Summer 2012 and 2013 respectively). Additional opportunist ship time being factored in to support the ambitious glider operations associated with OSMOSIS.
Instrumentation
Types of instrumentation and measurements associated with the OSMOSIS observational campaign:
- Ocean gliders
- Wave rider buoys
- Towed SeaSoar surveys
- Microshear measurements
- Moored current meters, conductivity-temperature sensors and ADCPs
- Traditional shipboard measurements (including CTD, underway, discrete nutrients, LADCP, ADCP).
Contacts
Collaborator | Organisation |
---|---|
Prof. Stephen Belcher | University of Reading, U.K |
Dr. Alberto C Naveira Garabato | University of Southampton, U.K |
Data Activity or Cruise Information
Data Activity
Start Date (yyyy-mm-dd) | 2012-09-21 |
End Date (yyyy-mm-dd) | 2012-09-21 |
Organization Undertaking Activity | National Oceanography Centre, Southampton |
Country of Organization | United Kingdom |
Originator's Data Activity Identifier | D381B_CTD_C010 |
Platform Category | lowered unmanned submersible |
BODC Sample Metadata Report for D381B_CTD_C010
Sample reference number | Nominal collection volume(l) | Bottle rosette position | Bottle firing sequence number | Minimum pressure sampled (dbar) | Maximum pressure sampled (dbar) | Depth of sampling point (m) | Bottle type | Sample quality flag | Bottle reference | Comments |
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919703 | 10.00 | 1 | 1 | 505.90 | 506.60 | 500.60 | Niskin bottle | No problem reported | ||
919706 | 10.00 | 2 | 2 | 505.70 | 506.70 | 500.60 | Niskin bottle | No problem reported | ||
919709 | 10.00 | 3 | 3 | 353.80 | 354.60 | 350.20 | Niskin bottle | Bottle leak | ||
919712 | 10.00 | 4 | 4 | 354.20 | 354.60 | 350.40 | Niskin bottle | Vent left open | ||
919715 | 10.00 | 5 | 5 | 303.70 | 304.50 | 300.60 | Niskin bottle | No problem reported | ||
919718 | 10.00 | 6 | 6 | 303.20 | 305.20 | 300.70 | Niskin bottle | No problem reported | ||
919721 | 10.00 | 7 | 7 | 203.60 | 204.00 | 201.30 | Niskin bottle | No problem reported | ||
919724 | 10.00 | 8 | 8 | 203.10 | 204.30 | 201.20 | Niskin bottle | No problem reported | ||
919727 | 10.00 | 9 | 9 | 152.70 | 153.00 | 150.80 | Niskin bottle | No problem reported | ||
919730 | 10.00 | 10 | 10 | 152.20 | 153.10 | 150.60 | Niskin bottle | No problem reported | ||
919733 | 10.00 | 11 | 11 | 102.50 | 103.70 | 101.50 | Niskin bottle | No problem reported | ||
919736 | 10.00 | 12 | 12 | 102.70 | 103.20 | 101.30 | Niskin bottle | No problem reported | ||
919739 | 10.00 | 13 | 13 | 77.30 | 77.80 | 76.20 | Niskin bottle | No problem reported | ||
919742 | 10.00 | 14 | 14 | 76.90 | 77.90 | 76.00 | Niskin bottle | Bottle leak | ||
919745 | 10.00 | 15 | 15 | 51.80 | 52.30 | 50.90 | Niskin bottle | No problem reported | ||
919748 | 10.00 | 16 | 16 | 51.30 | 52.70 | 50.80 | Niskin bottle | No problem reported | ||
919751 | 10.00 | 17 | 17 | 40.10 | 40.80 | 39.40 | Niskin bottle | No problem reported | ||
919754 | 10.00 | 18 | 18 | 40.00 | 40.80 | 39.30 | Niskin bottle | Bottle leak | ||
919757 | 10.00 | 19 | 19 | 26.90 | 27.20 | 26.10 | Niskin bottle | No problem reported | ||
919760 | 10.00 | 20 | 20 | 26.90 | 27.40 | 26.20 | Niskin bottle | No problem reported | ||
919763 | 10.00 | 21 | 21 | 11.70 | 12.60 | 11.30 | Niskin bottle | No problem reported | ||
919766 | 10.00 | 22 | 22 | 11.60 | 12.60 | 11.30 | Niskin bottle | No problem reported | ||
919769 | 10.00 | 23 | 23 | 5.60 | 6.10 | 5.10 | Niskin bottle | Bottle leak | ||
919772 | 10.00 | 24 | 24 | 5.30 | 5.90 | 4.80 | Niskin bottle | No problem reported |
Please note:the supplied parameters may not have been sampled from all the bottle firings described in the table above. Cross-match the Sample Reference Number above against the SAMPRFNM value in the data file to identify the relevant metadata.
Cruise
Cruise Name | D381B |
Departure Date | 2012-09-14 |
Arrival Date | 2012-10-03 |
Principal Scientist(s) | John T Allen (National Oceanography Centre, Southampton) |
Ship | RRS Discovery |
Complete Cruise Metadata Report is available here
Fixed Station Information
No Fixed Station Information held for the Series
BODC Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
Flag | Description |
---|---|
Blank | Unqualified |
< | Below detection limit |
> | In excess of quoted value |
A | Taxonomic flag for affinis (aff.) |
B | Beginning of CTD Down/Up Cast |
C | Taxonomic flag for confer (cf.) |
D | Thermometric depth |
E | End of CTD Down/Up Cast |
G | Non-taxonomic biological characteristic uncertainty |
H | Extrapolated value |
I | Taxonomic flag for single species (sp.) |
K | Improbable value - unknown quality control source |
L | Improbable value - originator's quality control |
M | Improbable value - BODC quality control |
N | Null value |
O | Improbable value - user quality control |
P | Trace/calm |
Q | Indeterminate |
R | Replacement value |
S | Estimated value |
T | Interpolated value |
U | Uncalibrated |
W | Control value |
X | Excessive difference |
SeaDataNet Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
Flag | Description |
---|---|
0 | no quality control |
1 | good value |
2 | probably good value |
3 | probably bad value |
4 | bad value |
5 | changed value |
6 | value below detection |
7 | value in excess |
8 | interpolated value |
9 | missing value |
A | value phenomenon uncertain |
B | nominal value |
Q | value below limit of quantification |