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Metadata Report for BODC Series Reference Number 1650977


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
Niskin bottle  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Dr Naomi Greenwood
Originating Organization Centre for Environment, Fisheries and Aquaculture Science Lowestoft Laboratory
Processing Status banked
Online delivery of data Download available - Ocean Data View (ODV) format
Project(s) Oceans 2025 Theme 3 WP3.3
 

Data Identifiers

Originator's Identifier PD06_07_CTD_PIGX_533:C001
BODC Series Reference 1650977
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2007-04-16 11:01
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 53.44896 N ( 53° 26.9' N )
Longitude 3.64662 W ( 3° 38.8' W )
Positional Uncertainty Unspecified
Minimum Sensor or Sampling Depth 2.8 m
Maximum Sensor or Sampling Depth 2.8 m
Minimum Sensor or Sampling Height 22.9 m
Maximum Sensor or Sampling Height 22.9 m
Sea Floor Depth 25.7 m
Sea Floor Depth Source -
Sensor or Sampling Distribution Unspecified -
Sensor or Sampling Depth Datum Unspecified -
Sea Floor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODERankUnitsTitle
ADEPZZ011MetresDepth (spatial coordinate) relative to water surface in the water body
BOTTFLAG1Not applicableSampling process quality flag (BODC C22)
CLSDFLP11Milligrams per cubic metreConcentration standard deviation of chlorophyll-a {chl-a CAS 479-61-8} per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and fluorometry
CPHLFLP11Milligrams per cubic metreConcentration of chlorophyll-a {chl-a CAS 479-61-8} per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and fluorometry
FIRSEQID1DimensionlessBottle firing sequence number
PHAEFLP11Milligrams per cubic metreConcentration of phaeopigments {pheopigments} per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and fluorometry
PHSDFLP11Milligrams per cubic metreConcentration standard deviation of phaeopigments {pheopigments} per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and fluorometry
ROSPOSID1DimensionlessBottle rosette position identifier
SAMPRFNM1DimensionlessSample reference number

Definition of BOTTFLAG

BOTTFLAGDefinition
0The sampling event occurred without any incident being reported to BODC.
1The filter in an in-situ sampling pump physically ruptured during sample resulting in an unquantifiable loss of sampled material.
2Analytical 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.
3The 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.
4During 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.
5Water was reported to be escaping from the bottle as the rosette was being recovered.
6The bottle seals were observed to be incorrectly seated and the bottle was only part full of water on recovery.
7Either 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).
8There is reason to doubt the accuracy of the sampling depth associated with the sample.
9The bottle air vent had not been closed prior to deployment giving rise to a risk of sample contamination through leakage.

Definition of Rank

  • Rank 1 is a one-dimensional parameter
  • Rank 2 is a two-dimensional parameter
  • Rank 0 is a one-dimensional parameter describing the second dimension of a two-dimensional parameter (e.g. bin depths for moored ADCP data)

Problem Reports

No Problem Report Found in the Database


Data Access Policy

Centre for Environment, Fisheries and Aquaculture Science (Cefas) data access conditions

The Centre for Environment, Fisheries and Aquaculture Science (Cefas) is an Executive Agency of the Department of Environment, Food and Rural Affairs (Defra), formerly the Ministry of Agriculture, Fisheries and Food (MAFF). It was also known previously as the Directorate of Fisheries Research (DFR). This data policy refers to data collected by the organisation under all titles.

  • These data have no specific confidentiality restrictions for academic users. However data are restricted for commercial requests and clearance must be obtained by BODC from Cefas before they are released.
  • 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 acknowledgement.
  • The recommended acknowledgement is: "This study uses data from the Centre for Environment, Fisheries and Aquaculture Science (Cefas), provided by the British Oceanographic Data Centre."

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 chlorophyll and phaeopigment series measured on RV Prince Madog cruise PD06_07

Data Originator

Naomi Greenwood, CEFAS, Lowestoft

Content of data series

Parameter Units Parameter code CTD Samples
Chlorophyll-a concentration mg m-3 CPHLFLP1 2
Chlorophyll-a concentration standard deviation mg m-3 CLSDFLP1 2
Phaeopigment concentration mg m-3 PHAEFLP1 2
Phaeopigment concentration standard deviation mg m-3 PHSDFLP1 2

Originator's Protocol

Samples for chlorophyll-a and associated phaeopigments were collected by CEFAS from water bottle rosette sampling systems mounted on the lowered CTD on POL Coastal Observatory cruise 43. Samples were collected near-surface from a total of 2 CTD stations.

For each sample, a 250ml sample is passed through a Whatman GF/F filter under low vacuum. The filter paper is folded in half, loosely wrapped in aluminium foil and placed in a plastic bag. Samples are stored in this way in a box containing desiccant at -18° C until analysis. Filters are extracted using 8ml 90% acetone and measured fluorometrically according to Tett (1987) for chlorophyll-a and phaeopigments. CEFAS use a Turner 10AU field fluorometer, which has been calibrated using a pure solution of chlorophyll-a.

BODC Processing

The data were supplied to BODC as an Excel spreadsheet. This was converted to an ASCII format file for loading into the BODC archive. Methodology and units were checked against information held in the BODC parameter dictionary and an appropriate parameter code was attributed to each variable. The file's data and metadata fields were then checked prior to loading into a database.

The data were loaded into the database under the Oracle Relational Database Management System by matching the sample's station identifier and depth with the information already held in the database for this cruise. Where the data supplied included multiple replicates for each station, the mean value and standard deviation were loaded into the database. For single samples, the data were loaded without further modification.

Comments

There is an 'M' flag on the mean phaeopigment concentration value for Station 1. This flag was applied because the 3 values used to calculate the mean were excessively variable, as evidenced by the very high standard deviation.

References

Tett , P. 1987. Plankton. In: Baker, J. M., Wolff, J. W. (Eds.), Biological surveys of estuaries and coasts. Cambridge University Press, Cambridge, pp 280-341.

Conditions of Use

  • The Data Originator must be informed that the supply has occurred.
  • Due acknowledgement of the Originator and the Originator's Institute is made by the receiver in any product using the data.
  • No commercial gain ensues from usage of the data.

CEFAS Disclaimer:
"Reproduction of this material is limited to academic and educational uses only and not for any commercial purposes without permission from CEFAS. The data are provided "as is" and in no event shall CEFAS be liable for any damages, including, without limitation, any disruption, damage and/or loss to your data or computer system that may occur while using this site or data. CEFAS makes no warranty, express or implied, including the warranties of merchantability and fitness for a particular purpose; nor assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any data, information, apparatus, product, or process disclosed; nor represents that its use would not infringe the rights of any third party."

BODC Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters within 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
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

Project Information

Oceans 2025 Theme 3, Work Package 3.3: Bottom Boundary Layer, Optics and Suspended Sediments Processes

This Work Package (WP) is a combination of Work Package 3.3 and 3.4 as proposed in the original Oceans 2025 proposal. It continues and expands the research undertaken in the Proudman Oceanographic Laboratory Dee Experiment project.

Sediment transport process models underpin scientific ability to predict the entrainment of sediments into the water column and the transport of sediments for forecasting seabed and coastal morphodynamic evolution. The difficulty in achieving accurate process models lies with the complex inter-dependence of sediment processes in the bottom boundary layer. Near the bed, the fundamentals of sediment transport are governed by interactions between the sediment transport triad; the bed, the hydrodynamics and the mobile sediments. These three components interrelate, being mutually interactive and interdependent.

POL aim to use a combination of high-frequency underwater acoustics and laser optical measurements to make co-located simultaneous measurements of the triad. These measurements provide an observational framework capable of assessing and advancing the latest sediment transport models available. These measurements will be made in a range of environments, with the objective of achieving significant advances in understanding and modelling capability in coastal sediment transport. POL will also address the dynamics of suspended sediment behaviour in the context of sediment supply to the coastal zone from estuaries, and of coastal water column optical properties. Ths will allow improvement of the modelling accuracy of coastal suspended sediment transport and enable development of a new description of sediment suspension and water opacity that will improve simulation of coastal primary productivity.

The specific objectives are:

  • Assess process-based models over different sediment types, cohesive to non-cohesive
  • Investigate intra-wave and turbulence processes over flat and rippled beds to improve process based sediment transport models; parameterisation of the process modelling output for input into large-scale area models
  • Advance the description and parameterisation of the impact benthic biota has on sediment transport processes (jointly with the Plymouth Marine Laboratory (PML))
  • Acquire new knowledge of the dynamics of sediment flocculation and its impact on suspended particulate material (SPM) in shelf seas and estuaries
  • Provide preliminary formulations for aggregation-disaggregation and test these formulations using shelf sea models of the Eastern Irish Sea
  • Develop understanding of the processes that affect the sediment fluxes between estuaries and the adjacent shelf sea.
  • Derive and apply formulations of the effects of SPM on optical attenuation and absorption and assess their potential impact on primary productivity using existing models

Fieldwork

The study site chosen by POL for this research was the Dee Estuary, Liverpool Bay. POL performed fieldwork in the Hilbre Channel on the eastern side of the Estuary and the Welsh Channel on the western exit of the Estuary, with emphasis placed on two repeat stations, HC and WC. The fieldwork under Work Package 3.3 commenced in April 2007 and has been summarised below:

Cruise Dates Hilbre Channel Welsh Channel
PD06_07 2007-04-16 to 2007-04-19 18 hour CTD station
Mooring recovery
15 hour CTD station
Mooring recovery
PD04_08 2008-02-12 to 2008-02-15 25 hour CTD station
2 x mooring deployment
19 hour CTD station
1 x mooring deployment
PD02_09A 2009-02-02 to 2009-02-04 25 hour CTD station
1 x mooring deployment
22 hour CTD station
1 mooring deployment
PD06_09 2009-03-03 to 2009-03-05 25 hour CTD station
Mooring recovery
18 hour CTD station
Mooring recovery

More detailed information on this Work Package is available at pages 8 - 9 and 9-10 of the official Oceans 2025 Theme 3 document: Oceans 2025 Theme 3

Weblink: http://www.oceans2025.org/


Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd) 2007-04-16
End Date (yyyy-mm-dd) 2007-04-16
Organization Undertaking ActivityProudman Oceanographic Laboratory (now National Oceanography Centre, Liverpool)
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierPD06_07_CTD_C001
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for PD06_07_CTD_C001

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
433044   3 1   25.00   25.30   24.50 Niskin bottle No problem reported    
433045   4 2   25.00   25.20   24.40 Niskin bottle No problem reported    
433046   9 3    3.00    3.50    2.80 Niskin bottle No problem reported    
433047   10 4    3.20    3.30    2.80 Niskin bottle No problem reported    
433048   11 5    3.00    3.30    2.70 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 PD06/07
Departure Date 2007-04-16
Arrival Date 2007-04-20
Principal Scientist(s)Alejandro J Souza (Proudman Oceanographic Laboratory)
Ship RV Prince Madog

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: PD06_07_CTD_C001

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 IdentifierData CategoryStart date/timeStart positionCruise
1320179Water sample data2007-04-16 11:01:0053.44896 N, 3.64662 WRV Prince Madog PD06/07