Metadata Report for BODC Series Reference Number 1869980
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 |
---|---|
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.
AMT17 extracted chlorophyll-a measured fluorometrically from CTD bottle samples
Data Acquisition and Analysis
These data originate from analyses on samples collected from CTD rosette bottles for all successful CTD casts and some samples collected from the ship's non-toxic supply while on station.
Water samples (300-500 ml) from CTD bottles were filtered on 25 mm GF/F filters. At a small number of stations the 1% and 55% of surface light level samples were size-fractionated with 2 µm and 0.2 µm 25 mm polycarbonate filters. Filters were extracted in 90% acetone for 24 hrs and total chlorophyll-a measured with a TD-700 Turner Designs fluorometer following the procedure of Welschmeyer (1994) which minimises interference by chlorophyll-b. The fluorometer was calibrated with dilutions of a solution of pure chlorophyll-a (Sigma, UK) in 90% acetone, the concentration of which was determined spectrophotometrically after the cruise.
References Cited
Welschmeyer N.A., 1994. Fluorometric analysis of chlorophyll-a in the presence of chlorophyll-b and phaeopigments. Limnology and Oceanography, 39, 1985-1992.
Instrumentation Description
Not relevant to this dataset.
BODC Data Processing Procedures
Data were submitted to BODC in an Excel spreadsheet and accessioned under BODC archive SOC060480. Sample metadata were checked against information held in the database. There were a number of discrepancies between combination of depth and bottle number of the samples provided in the file and those recorded on the log sheets and in the Sea-Bird bottle log files. Resolution of these discrepancies are listed in the table below.
CTD cast | Originator's Light Depth (%) | Originator's Depth (m) | Originator's CTD bottle number | Sea-Bird log file bottle depth (m) | Sea-Bird log file CTD bottle number | Comments |
---|---|---|---|---|---|---|
CTD006t | - | 20 | 22 | 10.5 | 22 | database depth link based on originator's CTD bottle number |
CTD006t | - | 40 | 15 | 19 | 15 | database depth link based on originator's CTD bottle number |
CTD015s | - | 85 | 10 | 96 | 10 | database depth link based on originator's CTD bottle number |
CTD017t | 97 | 2 | 24 | 12.4 | 24 | database depth link based on originator's CTD bottle number |
CTD017t | 14 | 46 | 19 | 56 | 19 | database depth link based on originator's CTD bottle number |
CTD017t | 1 | 105 | 14 | 114.9 | 14 | database depth link based on originator's CTD bottle number |
CTD021t | 14 | 54 | 18 | 44.7 | 18 | database depth link based on originator's CTD bottle number |
CTD021t | 1 | 114 | 9 | 102.1 | 9 | database depth link based on originator's CTD bottle number |
CTD043t | 14 | 17 | 19 | 75.5 | 19 | database depth link based on originator's CTD bottle number |
CTD046t | 0.1 | 261 | 4 | 272.1 | 8 | database depth link based on depth provided by originator since CTD bottle 4 was fired at depth ~3500 m and this is unlikely to relate to the 0.1% light depth indicated for this sample |
CTD059s | - | 60 | 12 | 29.7 | 12 | database depth link based on originator's CTD bottle number |
For the size-fractionated samples only the sum of the size-fractions were provided. There were two samples with replicate measurements provided and these were loaded as mean and standard deivation for these samples.
Parameter codes defined in BODC parameter dictionary were assigned to the variable. The units supplied in the spreadsheet were mg l-1, however comparison with data values reported from onboard calibration in the Cruise Report and sensor range of fluorometer (from manufacturer's website) suggests this is an error and the data should be labelled mg m-3(equivalent to µg l-1).
Data values loaded into BODC's database without any changes applied.
A parameter mapping table is provided below;
Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
---|---|---|---|---|---|
Chlorophyll-a | µg l-1 | Concentration of chlorophyll-a {chl-a} per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and fluorometry | CPHLFLP1 | mg m-3 | n/a |
- | - | Concentration standard deviation of chlorophyll-a {chl-a} per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and fluorometry | CLSDFLP1 | mg m-3 | n/a |
Chlorophyll-a >0.2 total | µg l-1 | Concentration of chlorophyll-a {chl-a} per unit volume of the water body [particulate >0.2 um phase] by filtration, acetone extraction and fluorometry | CPHLFLP4 | mg m-3 | n/a |
Data Quality Report
There was no indication that the dataset had been quality controlled prior to submission to BODC.
Problem Report
Not relevant to this dataset.
Project Information
The Atlantic Meridional Transect - Phase 2 (2002-2006)
Who was involved in the project?
The Atlantic Meridional Transect Phase 2 was designed by and implemented by a number of UK research centres and universities. The programme was hosted by Plymouth Marine Laboratory in collaboration with the National Oceanography Centre, Southampton. The universities involved were:
- University of Liverpool
- University of Newcastle
- University of Plymouth
- University of Southampton
- University of East Anglia
What was the project about?
AMT began in 1995, with scientific aims to assess mesoscale to basin scale phytoplankton processes, the functional interpretation of bio-optical signatures and the seasonal, regional and latitudinal variations in mesozooplankton dynamics. In 2002, when the programme restarted, the scientific aims were broadened to address a suite of cross-disciplinary questions concerning ocean plankton ecology and biogeochemistry and the links to atmospheric processes.
The objectives included the determination of:
- how the structure, functional properties and trophic status of the major planktonic ecosystems vary in space and time
- how physical processes control the rates of nutrient supply to the planktonic ecosystem
- how atmosphere-ocean exchange and photo-degradation influence the formation and fate of organic matter
The data were collected with the aim of being distributed for use in the development of models to describe the interactions between the global climate system and ocean biogeochemistry.
When was the project active?
The second phase of funding allowed the project to continue for the period 2002 to 2006 and consisted of six research cruises. The first phase of the AMT programme ran from 1995 to 2000.
Brief summary of the project fieldwork/data
The fieldwork on the first three cruises was carried out along transects from the UK to the Falkland Islands in September and from the Falkland Islands to the UK in April. The last three cruises followed a cruise track between the UK and South Africa, only deviating from the traditional transect in the southern hemisphere. During this phase the research cruises sampled further into the centre of the North and South Atlantic Ocean and also along the north-west coast of Africa where upwelled nutrient rich water is known to provide a significant source of climatically important gases.
Who funded the project?
Natural Environment Research Council (NERC)
Data Activity or Cruise Information
Data Activity
Start Date (yyyy-mm-dd) | 2005-11-21 |
End Date (yyyy-mm-dd) | 2005-11-21 |
Organization Undertaking Activity | Plymouth Marine Laboratory |
Country of Organization | United Kingdom |
Originator's Data Activity Identifier | AMT17_CTD_CTD054t |
Platform Category | lowered unmanned submersible |
BODC Sample Metadata Report for AMT17_CTD_CTD054t
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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184073 | 10.00 | 1 | 1 | 302.60 | 302.90 | 299.70 | Lever Action Niskin Bottle | No problem reported | ||
184074 | 10.00 | 2 | 2 | 303.00 | 304.00 | 300.50 | Lever Action Niskin Bottle | No problem reported | ||
184075 | 10.00 | 3 | 3 | 202.70 | 203.10 | 200.70 | Lever Action Niskin Bottle | No problem reported | ||
184076 | 10.00 | 4 | 4 | 202.60 | 203.20 | 200.70 | Lever Action Niskin Bottle | No problem reported | ||
184077 | 10.00 | 5 | 5 | 193.90 | 194.90 | 192.30 | Lever Action Niskin Bottle | No problem reported | ||
184078 | 10.00 | 6 | 6 | 171.40 | 171.90 | 169.70 | Lever Action Niskin Bottle | No problem reported | ||
184079 | 10.00 | 7 | 7 | 156.90 | 157.70 | 155.40 | Lever Action Niskin Bottle | No problem reported | ||
184080 | 10.00 | 8 | 8 | 146.30 | 146.90 | 144.80 | Lever Action Niskin Bottle | No problem reported | ||
184081 | 10.00 | 9 | 9 | 139.70 | 140.50 | 138.40 | Lever Action Niskin Bottle | No problem reported | ||
184082 | 10.00 | 10 | 10 | 136.30 | 136.60 | 134.70 | Lever Action Niskin Bottle | No problem reported | ||
184083 | 10.00 | 11 | 11 | 132.90 | 133.30 | 131.40 | Lever Action Niskin Bottle | No problem reported | ||
184084 | 10.00 | 12 | 12 | 130.30 | 130.60 | 128.80 | Lever Action Niskin Bottle | No problem reported | ||
184085 | 10.00 | 13 | 13 | 129.70 | 130.30 | 128.30 | Lever Action Niskin Bottle | No problem reported | ||
184086 | 10.00 | 14 | 14 | 127.20 | 128.10 | 126.00 | Lever Action Niskin Bottle | No problem reported | ||
184087 | 10.00 | 15 | 15 | 124.20 | 125.10 | 123.00 | Lever Action Niskin Bottle | No problem reported | ||
184088 | 10.00 | 17 | 16 | 118.80 | 119.30 | 117.50 | Lever Action Niskin Bottle | No problem reported | ||
184089 | 10.00 | 18 | 17 | 111.90 | 112.30 | 110.60 | Lever Action Niskin Bottle | No problem reported | ||
184090 | 10.00 | 19 | 18 | 101.30 | 102.30 | 100.30 | Lever Action Niskin Bottle | No problem reported | ||
184091 | 10.00 | 16 | 19 | 81.30 | 81.80 | 80.20 | Lever Action Niskin Bottle | No problem reported | ||
184092 | 10.00 | 20 | 20 | 57.80 | 58.20 | 56.90 | Lever Action Niskin Bottle | No problem reported | ||
184093 | 10.00 | 21 | 21 | 32.50 | 33.00 | 31.80 | Lever Action Niskin Bottle | No problem reported | ||
184094 | 10.00 | 22 | 22 | 17.70 | 18.10 | 17.00 | Lever Action Niskin Bottle | No problem reported | ||
184095 | 10.00 | 23 | 23 | 2.70 | 3.50 | 2.30 | Lever Action Niskin Bottle | No problem reported | ||
184096 | 10.00 | 24 | 24 | 3.30 | 3.70 | 2.70 | Lever Action 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 | D299 (AMT17) |
Departure Date | 2005-10-15 |
Arrival Date | 2005-11-28 |
Principal Scientist(s) | Patrick M Holligan (University of Southampton School of Ocean and Earth Science) |
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: AMT17_CTD_CTD054t
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 |
---|---|---|---|---|
1127164 | Water sample data | 2005-11-21 10:03:00 | 29.3196 S, 3.57947 W | RRS Discovery D299 (AMT17) |
1631642 | Water sample data | 2005-11-21 10:03:00 | 29.3196 S, 3.57947 W | RRS Discovery D299 (AMT17) |