Metadata Report for BODC Series Reference Number 1116535
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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Parameters |
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Problem Reports
No Problem Report Found in the Database
Data Quality Report - see processing documentation
Data quality information is included in the general documentation for this series. Please read.
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
SPX Bran+Luebbe Autoanalyser 3
The instrument uses continuous flow analysis (CFA) with a continuous stream of material divided by air bubbles into discrete segments in which chemical reactions occur. The continuous stream of liquid samples and reagents are combined and transported in tubing and mixing coils. The tubing passes the samples from one apparatus to the other with each apparatus performing different functions, such as distillation, dialysis, extraction, ion exchange, heating, incubation, and subsequent recording of a signal.
An essential principle of the system is the introduction of air bubbles. The air bubbles segment each sample into discrete packets and act as a barrier between packets to prevent cross contamination as they travel down the length of the tubing. The air bubbles also assist mixing by creating turbulent flow (bolus flow), and provide operators with a quick and easy check of the flow characteristics of the liquid.
Samples and standards are treated in an exactly identical manner as they travel the length of the tubing, eliminating the necessity of a steady state signal, however, since the presence of bubbles create an almost square wave profile, bringing the system to steady state does not significantly decrease throughput and is desirable in that steady state signals (chemical equilibrium) are more accurate and reproducible.
The autoanalyzer can consist of different modules including a sampler, pump, mixing coils, optional sample treatments (dialysis, distillation, heating, etc), a detector, and data generator. Most continuous flow analyzers depend on color reactions using a flow through colorimeter, however other methods have been developed that use ISE, flame photometry, ICAP, fluorometry, and so forth.
More details can be found in the manufacturer's introduction to autoanalysers and instrument description .
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 have a capacity between 1.7 and 30 L, while Lever Action bottles have a capacity between 1.7 and 12 L. Reversing thermometers may be attached to a spring-loaded disk that rotates through 180° on bottle closure.
AMT19 (JC039) Micro-molar nutrient measurements from CTD bottle samples
Originator's Protocol for Data Acquisition and Analysis
Water samples were taken from the Sea-Bird CTD rosette system. They were sub-sampled into acid-clean 60 ml HDPE (nalgene) sample bottles. Analysis for nutrients was completed within 3-4 hours of sampling in all cases. Clean handling techniques were employed to avoid contamination of the samples.
The main nutrient analyser was a 5-channel Bran and Luebbe AAIII segmented flow autoanalyser. The analytical chemical methodologies used were according to Brewer and Riley (1965) for nitrate, Grasshoff (1976) for nitrite and Kirkwood (1989) for phosphate and silicate.
References Cited
Brewer P.G. and Riley J.P., 1965. The automatic determination of nitrate in sea water. Deep-Sea Research, 12, 765-772.
Grasshoff K., 1976. Methods of seawater analysis. Verlag Chemie, Weiheim: 317 pp.
Kirkwood D.S., 1989. Simultaneous determination of selected nutrients in seawater. ICES CM1989/C:29, 12pp.
Instrumentation Description
Not relevant to this data set.
BODC Data Processing Procedures
Data were submitted to BODC in Microsoft Excel spreadsheet format and saved to the BODC archive with reference PML100283. Sample metadata were checked against information held in the database, there were a few minor discrepancies. Cast 2 had a depth of 200m provided for bottle 2 where this bottle was fired at 100m and no bottle was fired at 200m for this cast. Casts 26 and 47 had typos for two sample depths where a 1 had been prefixed onto the correct depth, these were corrected based on the rosette bottle number. Cast 69 had a depth of 175m provided for bottle 3 when this bottle was fired at 150m and no bottle sampled at 175m for this cast. For cast 54 there were a number of discrepancies between the log sheet and spreadsheet depth/rosette position combinations, from the logsheets the wrong rosette bottle sequence had been entered but the depths were correct.
No unit conversions were necessary as the units the data were supplied in the files matched the units for the parameter codes in the BODC Parameter Dictionary. The dataset was loaded to the database following BODC protocols.
A parameter mapping table is provided below;
| Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
|---|---|---|---|---|---|
| Nitrate+Nitrite (AAIII) | µmol l -1 | Concentration of nitrate+nitrite {NO 3 +NO 2 } per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis | NTRZAATX | µmol l -1 | - |
| Nitrite (AAIII) | µmol l -1 | Concentration of nitrite {NO 2 } per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis | NTRIAATX | µmol l -1 | - |
| Phosphate (AAIII) | µmol l -1 | Concentration of phosphate {PO 4 } per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis | PHOSAATX | µmol l -1 | - |
| Silicate (AAIII) | µmol l -1 | Concentration of silicate {SiO 4 } per unit volume of the water body [dissolved plus reactive particulate phase] by colorimetric autoanalysis | SLCAAATX | µmol l -1 | - |
Data Quality Report
Data provided were quality checked by originator and flagged accordingly. There were a number of data points flagged suspect by the originator due excessive noise in the values.
Measurement precision information from data originators: Samples in the database with a flag of "<" had concentrations below the specified detection limits.
Problem Report
Not applicable for this dataset.
Project Information
Oceans 2025 Theme 10, Sustained Observation Activity 1: The Atlantic Meridional Transect (AMT)
The Atlantic Meridional Transect has been operational since 1995 and through the Oceans 2025 programme secures funding for a further five cruises during the period 2007-2012. The AMT programme began in 1995 utilising the passage of the RRS James Clark Ross between the UK and the Falkland Islands southwards in September and northwards in April each year. Prior to Oceans 2025 the AMT programme has completed 18 cruises following this transect in the Atlantic Ocean. This sustained observing system aims to provide basin-scale understanding of the distribution of planktonic communities, their nutrient turnover and biogenic export in the context of hydrographic and biogeochemical provinces of the North and South Atlantic Oceans.
The Atlantic Meridional Transect Programme is an open ocean in situ observing system that will:
- give early warning of any fundamental change in Atlantic ecosystem functionng
- improve forecasts of the future ocean state and associated socio-economic impacts
- provide a "contextual" logistical and scientific infrastructure for independently-funded national and international open ocean biogeochemical and ecological research.
The specific objectives are:
- To collect hydrographic, chemical, ecological and optical data on transects between the UK and the Falkland Islands
- To quantify the nature and causes of ecological and biogeochemical variability in planktonic ecosystems
- To assess the effects of variability in planktonic ecosystems on biogenic export and on air-sea exchange of radiatively active gases
The measurements taken and experiments carried out on the AMT cruises will be closely linked to Themes 2 and 5. The planned cruise track also allows for the AMT data to be used in providing spatial context to the Sustained Observation Activities at the Porcupine Abyssal Plain Ocean Observatory (SO2) and the Western Channel Observatory (SO10).
More detailed information on this Work Package is available at pages 6 - 9 of the official Oceans 2025 Theme 10 document: Oceans 2025 Theme 10
Weblink: http://www.oceans2025.org/
Data Activity or Cruise Information
Data Activity
| Start Date (yyyy-mm-dd) | 2009-10-27 |
| End Date (yyyy-mm-dd) | 2009-10-27 |
| Organization Undertaking Activity | Plymouth Marine Laboratory |
| Country of Organization | Germany |
| Originator's Data Activity Identifier | JC039_CTD_CTD039T |
| Platform Category | lowered unmanned submersible |
BODC Sample Metadata Report for JC039_CTD_CTD039T
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 228673 | 10.00 | 1 | 1 | 394.10 | 395.10 | 391.00 | Lever Action Niskin Bottle | No problem reported | ||
| 228674 | 10.00 | 2 | 2 | 343.20 | 344.20 | 340.50 | Lever Action Niskin Bottle | No problem reported | ||
| 228675 | 10.00 | 3 | 3 | 302.60 | 303.60 | 300.30 | Lever Action Niskin Bottle | No problem reported | ||
| 228676 | 10.00 | 4 | 4 | 262.20 | 263.20 | 260.20 | Lever Action Niskin Bottle | No problem reported | ||
| 228677 | 10.00 | 5 | 5 | 202.30 | 203.30 | 200.70 | Lever Action Niskin Bottle | No problem reported | ||
| 228678 | 10.00 | 6 | 6 | 176.90 | 177.90 | 175.50 | Lever Action Niskin Bottle | No problem reported | ||
| 228679 | 10.00 | 7 | 7 | 151.50 | 152.50 | 150.30 | Lever Action Niskin Bottle | No problem reported | ||
| 228680 | 10.00 | 8 | 8 | 131.60 | 132.60 | 130.50 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 1% | |
| 228681 | 10.00 | 19 | 9 | 131.40 | 132.40 | 130.30 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 1% | |
| 228682 | 10.00 | 20 | 10 | 131.50 | 132.50 | 130.40 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 1% | |
| 228683 | 10.00 | 21 | 11 | 131.20 | 132.20 | 130.10 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 1% | |
| 228684 | 10.00 | 9 | 12 | 100.90 | 101.90 | 100.10 | Lever Action Niskin Bottle | No problem reported | ||
| 228685 | 10.00 | 10 | 13 | 81.20 | 82.20 | 80.50 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 7% | |
| 228686 | 10.00 | 22 | 14 | 80.70 | 81.70 | 80.00 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 7% | |
| 228687 | 10.00 | 11 | 15 | 60.60 | 61.60 | 60.00 | Lever Action Niskin Bottle | No problem reported | ||
| 228688 | 10.00 | 12 | 16 | 40.70 | 41.70 | 40.30 | Lever Action Niskin Bottle | No problem reported | ||
| 228689 | 10.00 | 13 | 17 | 20.60 | 21.60 | 20.30 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 55% | |
| 228690 | 10.00 | 23 | 18 | 20.80 | 21.80 | 20.50 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 55% | |
| 228691 | 10.00 | 14 | 19 | 10.30 | 11.30 | 10.10 | Lever Action Niskin Bottle | No problem reported | ||
| 228692 | 10.00 | 15 | 20 | 2.10 | 3.10 | 1.90 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 97% | |
| 228693 | 10.00 | 16 | 21 | 2.20 | 3.20 | 2.00 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 97% | |
| 228694 | 10.00 | 17 | 22 | 2.10 | 3.10 | 1.90 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 97% | |
| 228695 | 10.00 | 18 | 23 | 2.20 | 3.20 | 2.00 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 97% | |
| 229639 | 10.00 | 24 | 24 | 2.10 | 3.10 | 1.90 | Lever Action Niskin Bottle | No problem reported | Nominal light depth: 97% |
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.
Other Series linked to this Data Activity - 1630337
Cruise
| Cruise Name | JC039 (AMT19, JC040) |
| Departure Date | 2009-10-13 |
| Arrival Date | 2009-12-01 |
| Principal Scientist(s) | Andrew Rees (Plymouth Marine Laboratory) |
| 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 |
| Q | value below limit of quantification |
