Metadata Report for BODC Series Reference Number 2125376
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
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.
Oxygen measurements for UK SOLAS cruise D338
Originator's Data Acquisition and Analysis
A total of 430 oxygen samples were collected from 46 CTD casts during D338. Samples were drawn from the Niskin bottles using silicone tubing, which was inserted into the bottom of each glass Oxygen bottle (nominal volume 125 ml). The sample bottle was allowed to overflow with several times its volume. The bottle was stoppered immediately, ensuring that no air was trapped inside.
Dissolved oxygen was determined by automated Winkler titration with photometric end-point detection (Carritt and Carpenter, 1966). The concentration of thiosulphate was calibrated every 2 days against potassium iodate standard.
References Cited
Carritt D.E. and Carpenter, J.H., 1966. Comparison and evaluation of currently employed modifications of the Winkler method for determining dissolved oxygen in seawater. A NASCO report. Journal of Marine Research, 24, 286-318.
BODC Data Processing Procedures
Data were received by BODC in a Microsoft Excel spreadsheet (D338_Oxygen_CTD_calibration.xls), which contained oxygen sample concentration and saturation along with the following metadata fields: longitude, latitude, cast and bottle number, depth, and oxygen saturation. The spreadsheet, which was used by the data originator to derive a calibration for the CTD in situ oxygen sensor, also contained coincidental CTD sensor oxygen from the bottle firing depths. CTD in situ sensor data are held separately from discrete sample data by BODC.
Parameter codes defined in the BODC parameter dictionary were mapped to the variables as follows:
Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
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O2W | µmol L-1 | Concentration of dissolved oxygen per unit volume of the water body by Winkler titration | DOXYWITX | µmol L-1 | n/a |
n/a | µmol L-1 | Concentration standard deviation of dissolved oxygen per unit volume of the water body by Winkler titration | SDOXWITX | µmol L-1 | Oxygen standard deviation was computed by BODC for the few samples that were analysed in duplicate and had to be averaged prior to loading in the database. |
The data were banked according to BODC standard procedures for discrete sample data. A few samples from CTD casts 042 and 046 were analysed in duplicate. BODC computed and banked the means and standard deviations of these data.
Data Quality Report
The originator flagged as suspect a small number (21) of the measurements. These flags were translated to the BODC quality control scheme and banked along with the data.
Users should be aware that some of the sampling depths supplied for cast 34 conflicted with those given, for the same bottle numbers, in both the cruise CTD log and the SeaBird files. This affected the top 6 bottles (rosette positions 7, 10, 13, 16, 21 and 24) in the upper 43 m. Variations in dissolved oxygen concentration in that depth range were small and the values could not be used to decide which source to trust. As a result and in consultation with the originators, BODC linked the data to the depth corresponding to the rosette position supplied.
Project Information
UK Surface Ocean Lower Atmosphere Study
The UK Surface Ocean Lower Atmosphere Study (UK SOLAS) is the UK's contribution to the international SOLAS programme.
UK SOLAS formed interdisciplinary teams to address three primary aims
- To determine the mechanisms controlling rates of chemical transfer and improve estimates of chemical exchanges
- To evaluate the impact of these exchanges on the biogeochemistry of the surface ocean and lower atmosphere and on feedbacks between the ocean and atmosphere
- To quantify the impacts of these boundary layer processes on the global climate system
UK SOLAS started in 2003, to run for seven years. The programme was funded by the Natural Environment Research Council.
Funded projects
In total, 19 projects have been funded by UK SOLAS, over four funding rounds.
Project Title | Short Title | Principal Investigator |
---|---|---|
Impact of atmospheric dust derived material and nutrient inputs on near-surface plankton microbiota in the tropical North Atlantic | Dust | Eric Achterberg |
The role and effects of photoprotective compounds in marine plankton | - | Steve Archer |
Field observations of sea spray, gas fluxes and whitecaps | SEASAW | Ian Brooks |
Factors influencing the biogeochemistry of iodine in the marine environment | - | Lucy Carpenter |
Global model of aerosol processes - effects of aerosol in the marine atmospheric boundary layer | GLOMAP | Ken Carslaw |
Ecological controls on fluxes of dimethyl sulphide (DMS) to the atmosphere | - | David Green |
Dust outflow and deposition to the ocean | DODO | Ellie Highwood |
Investigation of near surface production of iodocarbons - rates and exchanges | INSPIRE | Gill Malin |
Reactive halogens in the marine boundary layer | RHaMBLe | Gordon McFiggans |
The role of bacterioneuston in determining trace gas exchange rates | - | Colin Murrell |
Measuring methanol in sea water and investigating its sources and sinks in the marine environment | - | Phil Nightingale |
The impact of coastal upwellings on air-sea exchange of climatically important gases | ICON | Carol Robinson |
The Deep Ocean Gas Exchange Experiment | DOGEE | Rob Upstill-Goddard |
High wind air-sea exchanges | HiWASE | Margaret Yelland |
Aerosol characterisation and modelling in the marine environment | ACMME | James Allan |
3D simulation of dimethyl sulphide (DMS) in the north east Atlantic | - | Icarus Allen |
Processes affecting the chemistry and bioavailability of dust borne iron | - | Michael Krom |
The chemical structure of the lowermost atmosphere | - | Alastair Lewis |
Factors influencing the oxidative chemistry of the marine boundary layer | - | Paul Monks |
UK SOLAS has also supported ten tied studentships, and two CASE studentships.
Fieldwork
UK SOLAS fieldwork has included eight dedicated research cruises in the North Atlantic Ocean. Continuous measurements were made aboard aboard the Norwegian weather ship, Polarfront, until her decommission in 2009. Time series have been established at the SOLAS Cape Verde Observatory, and at the Plymouth Marine Laboratory L4 station. Experiments have taken place at the Bergen mesocosm facility.
A series of collaborative aircraft campaigns have added complementary atmospheric data. These campaigns were funded by UK SOLAS, African Monsoon Multidisciplinary Analyses (AMMA-UK), Dust and Biomass Experiment (DABEX) and the Facility for Airborne Atmospheric Measurements (FAAM).
Weblink: http://www.nerc.ac.uk/research/programmes/solas/
Data Activity or Cruise Information
Data Activity
Start Date (yyyy-mm-dd) | 2009-04-25 |
End Date (yyyy-mm-dd) | 2009-04-25 |
Organization Undertaking Activity | University of East Anglia School of Environmental Sciences |
Country of Organization | United Kingdom |
Originator's Data Activity Identifier | D338_CTD_CTD_031 |
Platform Category | lowered unmanned submersible |
BODC Sample Metadata Report for D338_CTD_CTD_031
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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206040 | 20.00 | 1 | 1 | 364.40 | 364.80 | 362.00 | Niskin bottle | No problem reported | ||
206041 | 10.00 | 2 | 2 | 364.40 | 364.70 | 362.00 | Niskin bottle | No problem reported | ||
206042 | 20.00 | 3 | 3 | 364.40 | 364.70 | 362.00 | Niskin bottle | No problem reported | ||
206043 | 20.00 | 4 | 4 | 203.90 | 204.40 | 202.80 | Niskin bottle | No problem reported | ||
206044 | 20.00 | 5 | 5 | 203.60 | 204.40 | 202.60 | Niskin bottle | No problem reported | ||
206045 | 20.00 | 6 | 6 | 103.30 | 103.90 | 102.90 | Niskin bottle | No problem reported | ||
206046 | 20.00 | 7 | 7 | 82.90 | 83.30 | 82.60 | Niskin bottle | No problem reported | ||
206047 | 20.00 | 8 | 8 | 82.90 | 83.30 | 82.60 | Niskin bottle | No problem reported | ||
206048 | 20.00 | 9 | 9 | 62.80 | 63.40 | 62.70 | Niskin bottle | No problem reported | ||
206049 | 20.00 | 10 | 10 | 62.80 | 63.10 | 62.60 | Niskin bottle | No problem reported | ||
206050 | 20.00 | 11 | 11 | 57.50 | 57.80 | 57.30 | Niskin bottle | No problem reported | ||
206051 | 20.00 | 12 | 12 | 57.40 | 57.80 | 57.20 | Niskin bottle | No problem reported | ||
206052 | 20.00 | 13 | 13 | 52.50 | 52.80 | 52.30 | Niskin bottle | No problem reported | ||
206053 | 20.00 | 14 | 14 | 52.50 | 52.80 | 52.30 | Niskin bottle | No problem reported | ||
206054 | 20.00 | 15 | 15 | 42.60 | 42.90 | 42.50 | Niskin bottle | No problem reported | ||
206055 | 20.00 | 16 | 16 | 42.60 | 42.90 | 42.50 | Niskin bottle | No problem reported | ||
206056 | 20.00 | 17 | 17 | 42.60 | 42.80 | 42.40 | Niskin bottle | No problem reported | ||
206057 | 20.00 | 18 | 18 | 22.40 | 22.90 | 22.50 | Niskin bottle | No problem reported | ||
206058 | 10.00 | 19 | 19 | 22.40 | 22.80 | 22.50 | Niskin bottle | No problem reported | ||
206059 | 20.00 | 20 | 20 | 9.30 | 9.70 | 9.40 | Niskin bottle | No problem reported | ||
206060 | 20.00 | 21 | 21 | 9.50 | 9.60 | 9.50 | Niskin bottle | No problem reported | ||
206061 | 20.00 | 22 | 22 | 3.00 | 3.40 | 3.20 | Niskin bottle | No problem reported | ||
206062 | 20.00 | 23 | 23 | 2.70 | 3.80 | 3.20 | Niskin bottle | No problem reported | ||
206063 | 20.00 | 24 | 24 | 2.80 | 3.50 | 3.10 | 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.
Related Data Activity activities are detailed in Appendix 1
Cruise
Cruise Name | D338 |
Departure Date | 2009-04-15 |
Arrival Date | 2009-05-27 |
Principal Scientist(s) | Carol Robinson (University of East Anglia School of Environmental Sciences) |
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 |
Appendix 1: D338_CTD_CTD_031
Related series for this Data Activity are presented in the table below. Further information can be found by following the appropriate links.
If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.
Series Identifier | Data Category | Start date/time | Start position | Cruise |
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1248121 | Water sample data | 2009-04-25 11:36:00 | 20.82279 N, 17.68272 W | RRS Discovery D338 |