Metadata Report for BODC Series Reference Number 1711562
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.
Pigments on RRS Challenger, RV Sea Vigil and RV Water Guardian cruises.
Document History
Converted from CDROM documentation
Data series content
CPHLFLP1 | Fluorometric chlorophyll-a |
Fluorometric assay of acetone extract (GF/F filtered) | |
Milligrams per cubic metre | |
CPHLFLP5 | Fluorometric chlorophyll-a |
Fluorometric assay of acetone extract (0.2 micron pore filtered) | |
Milligrams per cubic metre | |
CPHLPR01 | In-situ fluorometer chlorophyll-a |
Calibrated in-situ fluorometer | |
Milligrams per cubic metre | |
CPHLSPP1 | Spectrophotometric chlorophyll-a (Lorenzen) |
Spectrophotometric assay of acetone extract (GF/F filtered) | |
Milligrams per cubic metre | |
PHAEFLP1 | Fluorometric phaeopigments |
Fluorometric assay of acetone extract (GF/F filtered) | |
Milligrams per cubic metre | |
PHAEFLP5 | Fluorometric phaeopigments |
Fluorometric assay of acetone extract (0.2 micron pore filtered) | |
Milligrams per cubic metre |
Data Originator
Dr Reg Uncles, Plymouth Marine Laboratory, UK.
Sampling strategy and methodology
RRS Challenger cruises CH108A. CH108C, CH115A, CH115B, CH115C, CH117A0, CH117A, CH117B, CH118A, CH118B, CH118C, CH119A, CH119B and CH119C.
RV Sea Vigil cruises SV6A, SV6B, SV7A, SV7B, SV7C, SV9A, SV9B, SV10A, SV10B, SV12A, SV12B, SV13A, SV13B, SV14B, SV14C, SV15A, SV15B, SV16, SV18B, SV19A and SV19B.
RV Water Guardian cruises WG11A, WG11B and WG11C.
Water samples were collected from either water bottles on the CTD rosette (Challenger cruises only) or the ships' non-toxic surface water supply and aliquots of approximately 100ml were filtered through 0.2-micron pore size membrane filters.
The pigments were extracted into 90% acetone and assayed fluorometrically before and after acidification to obtain estimates of chlorophyll-a and phaeopigments. The analytical procedures were frequently completed on board ship to eliminate problems of pigment degradation during sample storage.
BODC has serious concerns about the quality of the Challenger cruise pigment data. Initial inspection of the data set revealed obvious errors, with incredibly high chlorophyll values. Investigations showed that there was a 'rogue' copy of the processing spreadsheet in circulation with formulae errors that caused the data to be scaled by a factor of 10. Wherever data were positively identified as affected by this they were corrected at BODC.
After correction, the majority of the data looked reasonable, but during the CTD fluorometer calibrations it became obvious that there were still significant errors in the data (high chlorophylls associated with low CTD fluorescence and vice versa). Many data values were eliminated from the calibrations and flagged as suspect. The data that remain seem credible, but users are recommended to treat them with caution.
References
Lorenzen, C.J. and Jeffrey, S.W., 1978. Determination of chlorophyll in seawater. UNESCO Techn. Paper Mar Sci, 35.
Project Information
LOIS River-Atmosphere-Coast Study (LOIS - RACS)
Introduction
The Land-Ocean Interaction Study (LOIS) was a NERC research programme designed to study processes in the coastal zone. The Rivers, Atmosphere and Coasts Study (RACS) was a major component of LOIS that looked at land-sea interactions in the coastal zone and the major exchanges (physical, chemical and biological) between rivers and estuaries and the atmosphere. The study focused on the east coast of the UK from the Wash to the Tweed.
RACS included several sub-components
- BIOTA - A study of salt marshes of the Humber and Wash
- RACS (A) - An atmospheric chemistry study looking at air mass changes from the Wash into East Anglia
- RACS (C) - A study of the estuaries, coasts and coastal waters between Great Yarmouth and Berwick upon Tweed.
1. The coastal oceangraphic survey
2. The Humber estuarine study
3. The Tweed estuarine study
4. The Holderness experiment - RACS (R) - A study of rivers that drain into the North Sea
RACS (A) was coordinated by the University of East Anglia and RACS (C) by the Plymouth Marine Laboratory.
RACS (A)
The bulk of the RACS (A) data set was collected during two field campaigns in the winter (October/November) of 1994 and the summer (May/June) of 1995. During these campaigns data were collected continuously from the University of East Anglia Atmospheric Observatory at Weybourne on the north Norfolk coast. An instrumented vessel was stationed offshore to provide a second sampling site to allow changes in a given air mass to be monitored. The Imperial College Jetstream research aircraft made one flight during each campaign to provide a link between the two surface stations. The Jetstream made four additional flights in 1996 and 1997.
RACS (C)
The coastal oceanographic survey
The coastal oceanographic data set was collected during a series of 17 RRS Challenger cruise legs. Most cruises covered two survey grids. One from Great Yarmouth to the Humber designed around the distribution of the sandbanks and a second simple zig-zag grid from the Humber to Berwick on Tweed. A large number of anchor stations, usually over one or two tidal cycles, were worked in the area of the Humber mouth or the Holderness coast.
The Humber estuarine study
The Humber estuarine data set was collected during a series of 33 campaigns on the Environment Agency vessels Sea Vigil and Water Guardian in the Humber, Trent and Ouse river systems at approximately monthly intervals between June 1993 and December 1996. Each campaign consisted of two or three one-day cruises. The tracks covered the estuary from the tidal limits of both Trent and Ouse to Spurn Point. Instrumental and sample data are available from a series of fixed stations that were sampled during every campaign.
The Tweed estuarine study
The Tweed estuarine data set was collected during a series of 13 campaigns using RV Tamaris in association with a rigid inflatable vessel at approximately monthly intervals between July 1996 and July 1997. Each campaign covered the tidal reaches of the River Tweed.
The Holderness experiment
The Holderness Experiment was designed to monitor the process of sediment transport along the Holderness coastline. It consisted of three moored instrument deployments during the winters of 1993-1994, 1994-1995 and 1995-1996. Mooring platforms were deployed at eight stations along two lines off the Holderness coast. A northerly and a southerly line of four stations each were used (N1 - N4 and S1 to S4) with the lowest numbers being inshore. Both lines were approximately perpendicular to the coast, although the S4 station lay to the south of the S line, off Spurn Head.
Data Activity or Cruise Information
Data Activity
Start Date (yyyy-mm-dd) | 1994-10-09 |
End Date (yyyy-mm-dd) | 1994-10-09 |
Organization Undertaking Activity | Proudman Oceanographic Laboratory (now National Oceanography Centre, Liverpool) |
Country of Organization | United Kingdom |
Originator's Data Activity Identifier | CH115A_CTD_CP101 |
Platform Category | lowered unmanned submersible |
BODC Sample Metadata Report for CH115A_CTD_CP101
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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364859 | 10.00 | 14.80 | 15.30 | 14.30 | Niskin bottle | No problem reported | ||||
364860 | 10.00 | 3.80 | 4.30 | 3.40 | 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.
Cruise
Cruise Name | CH115A |
Departure Date | 1994-10-04 |
Arrival Date | 1994-10-17 |
Principal Scientist(s) | David Prandle (Proudman Oceanographic Laboratory) |
Ship | RRS Challenger |
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 |
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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 |
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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 |