Metadata Report for BODC Series Reference Number 1334279
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
These data have no specific confidentiality restrictions for users. However, users must acknowledge data sources as it is not ethical to publish data without proper attribution. Any publication or other output resulting from usage of the data should include an acknowledgment.
If the Information Provider does not provide a specific attribution statement, or if you are using Information from several Information Providers and multiple attributions are not practical in your product or application, you may consider using the following:
"Contains public sector information licensed under the Open Government Licence v1.0."
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.
Discrete inorganic nutrient (N, P, Si) samples from CTD bottles during RRS James Cook cruise 32 (JC032)
Originator's Protocol for Data Acquisition and Analysis
Seawater was collected from depth for the analysis of micro-molar concentrations of dissolved inorganic nutrients: nitrate and nitrite (hereafter nitrate), phosphate and silicate. Water was collected from depth using a stainless steel CTD frame fitted with a Sea-Bird SBE 32, twenty-four way carousel (s/n 32-19817-0243) equipped with 20, ten litre OTE external spring water samplers (rosette positions 1-20) and 4, twenty litre OTE external spring water samplers (rosette positions 21-24). All stations occupied during JC032 were sampled for nutrients except stations 22 and 48 (see appendix of the cruise report). Sampling for inorganic nutrients occurred after sampling for chlorofluorocarbons (CFC), dissolved oxygen, argon, carbonate system and salinity. Samples were collected from most CTD bottle depths and spanned the whole water column. Inorganic nutrient concentrations were analysed using a segmented-flow nutrient autoanalyser with colourimetric detection (Skalar SANplus SYSTEM analyser (type 4000) fitted with a Skalar autosampler (type 1000)). The samples were run in analytical triplicates and averaged. The system was calibrated against nitrate (1-40 µmol L-1), phosphate (0.5-4 µmol L-1) and silicate (1-120 µmol L-1) laboratory standards made in artificial seawater (40 g NaCl L-1) for every run. Efficiency of the cadmium column was checked for each run against a 40 µmol L-1 nitrite standard. Sample variability of triplicates was <0.8%. The limits of detection were 0.03 µmol L-1 for phosphate, 0.15 µmol L-1 for nitrate and 0.2 µmol L-1 for silicate. More detailed information on the methods used can be found in the cruise report from page 49.
BODC Data Processing Procedures
Inorganic nutrient measurements were provided to BODC in units of µmol kg-1 and µmol L-1. Data in µmol kg-1 were provided in a Comma Separated Values (.csv) file which conformed to the WHP Exchange format. The file contained CTD upcast sensor readings and numerous discrete bottle measurements at bottle firing depths for all CTD casts. Data in µmol L-1 were provided in MSTAR format NetCDF files, one for each CTD cast. The NetCDF files only contained discrete bottle measurements for nutrients at bottle firing depths. All measurements for nutrients were the average of analytical triplicates. All measurements for nutrients (per kg and per L) were loaded into the BODC database using established BODC data banking procedures. The following changes to the data occurred:
- Absent data: absent data were removed prior to loading.
- Quality control flags: WOCE quality control flags were converted to the corresponding BODC marker.
The data were then loaded to the database without any further changes. The originator's parameters were mapped to appropriate BODC parameter codes as shown below:
Comma Separated Values format file:
Originator's variable | Units | Description | BODC code | Units | Comments |
CTDPRS | db | Pressure (CTD sensor) | loaded separately | ||
CTDTMP | deg C | Temperature (CTD sensor) | loaded separately | ||
CTDSAL | PSS-78 | Salinity (CTD sensor) | loaded separately | ||
SALNTY | PSS-78 | Salinity | loaded separately | ||
CTDOXY | µmol kg-1 | Oxygen (CTD sensor) | loaded separately | ||
OXYGEN | µmol kg-1 | Oxygen | loaded separately | ||
SILCAT | µmol kg-1 | Silicate | SLCAMS01 | µmol kg-1 | |
NO2+NO3 | µmol kg-1 | Nitrate + nitrite | NTRAMS01 | µmol kg-1 | |
PHSPHT | µmol kg-1 | Phosphate | PHOSMS01 | µmol kg-1 | |
CFC-11 | pmol kg-1 | cfc-11 | loaded separately | ||
CFC-12 | pmol kg-1 | cfc-12 | loaded separately | ||
CFC113 | pmol kg-1 | cfc-113 | loaded separately | ||
CCL4 | pmol kg-1 | Carbon tetrachloride | loaded separately | ||
TCARBN | µmol kg-1 | Total carbon | loaded separately | ||
ALKALI | µmol kg-1 | Total alkalinity | loaded separately | ||
THETA | µmol kg-1 | Sigma-theta | Not loaded - derived | ||
SF6 | fmol kg-1 | Sulphur hexafluoride | loaded separately |
MSTAR NetCDF files:
Originator's variable | Units | Description | BODC code | Units | Comments |
no3 | µmol L-1 | Nitrate + nitrite | NTRZAATX | µmol L-1 | |
po4 | µmol L-1 | Phosphate | PHOSAATX | µmol L-1 | |
sio4 | µmol L-1 | Silicate | SLCAAATX | µmol L-1 |
Data Quality Report
A list of data quality and autoanalyser performance observations can be found from page 51 of the cruise report. (Originator's assessment)
Problem Report
None. (BODC assessment)
Project Information
No Project Information held for the Series
Data Activity or Cruise Information
Data Activity
Start Date (yyyy-mm-dd) | 2009-04-13 |
End Date (yyyy-mm-dd) | 2009-04-13 |
Organization Undertaking Activity | National Oceanography Centre, Southampton |
Country of Organization | United Kingdom |
Originator's Data Activity Identifier | JC032_CTD_A09.5/94 |
Platform Category | lowered unmanned submersible |
BODC Sample Metadata Report for JC032_CTD_A09.5/94
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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202703 | 10.00 | 4 | 4565.00 | 4566.00 | 4488.40 | Niskin bottle | No problem reported | 4 | ||
202704 | 10.00 | 16 | 753.30 | 754.30 | 747.60 | Niskin bottle | No problem reported | 16 | ||
202828 | 10.00 | 1 | 5251.70 | 5252.70 | 5155.60 | Niskin bottle | No problem reported | 1 | ||
202829 | 10.00 | 2 | 5199.40 | 5200.40 | 5104.80 | Niskin bottle | No problem reported | 2 | ||
202830 | 10.00 | 3 | 5080.10 | 5081.10 | 4989.00 | Niskin bottle | No problem reported | 3 | ||
202831 | 10.00 | 5 | 4051.40 | 4052.40 | 3988.10 | Niskin bottle | No problem reported | 5 | ||
202832 | 10.00 | 6 | 3540.90 | 3541.90 | 3489.70 | Niskin bottle | No problem reported | 6 | ||
202833 | 10.00 | 7 | 3029.40 | 3030.40 | 2989.10 | Niskin bottle | No problem reported | 7 | ||
202834 | 10.00 | 8 | 2521.30 | 2522.30 | 2490.80 | Niskin bottle | No problem reported | 8 | ||
202835 | 10.00 | 9 | 2268.40 | 2269.40 | 2242.30 | Niskin bottle | No problem reported | 9 | ||
202836 | 10.00 | 10 | 2015.60 | 2016.60 | 1993.70 | Niskin bottle | No problem reported | 10 | ||
202837 | 10.00 | 11 | 1761.40 | 1762.40 | 1743.30 | Niskin bottle | No problem reported | 11 | ||
202838 | 10.00 | 12 | 1509.90 | 1510.90 | 1495.40 | Niskin bottle | No problem reported | 12 | ||
202839 | 10.00 | 13 | 1257.50 | 1258.50 | 1246.20 | Niskin bottle | No problem reported | 13 | ||
202840 | 10.00 | 14 | 1004.60 | 1005.60 | 996.30 | Niskin bottle | No problem reported | 14 | ||
202841 | 10.00 | 15 | 879.70 | 880.70 | 872.70 | Niskin bottle | No problem reported | 15 | ||
202842 | 10.00 | 17 | 627.90 | 628.90 | 623.50 | Niskin bottle | No problem reported | 17 | ||
202843 | 10.00 | 18 | 502.50 | 503.50 | 499.20 | Niskin bottle | No problem reported | 18 | ||
202844 | 10.00 | 19 | 376.90 | 377.90 | 374.70 | Niskin bottle | No problem reported | 19 | ||
202845 | 10.00 | 20 | 252.40 | 253.40 | 251.10 | Niskin bottle | No problem reported | 20 | ||
202846 | 20.00 | 21 | 177.40 | 178.40 | 176.70 | Niskin bottle | No problem reported | 25 | ||
202847 | 20.00 | 22 | 102.10 | 103.10 | 101.90 | Niskin bottle | No problem reported | 22 | ||
202848 | 20.00 | 23 | 51.90 | 52.90 | 52.10 | Niskin bottle | No problem reported | 23 | ||
202849 | 20.00 | 24 | 7.50 | 8.50 | 7.90 | Niskin bottle | No problem reported | 24 |
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 | JC032 |
Departure Date | 2009-03-07 |
Arrival Date | 2009-04-21 |
Principal Scientist(s) | Brian A King (National Oceanography Centre, Southampton) |
Ship | RRS James Cook |
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 |