Metadata Report for BODC Series Reference Number 1686471


Metadata Summary

Data Description

Data Category Water sample data
Instrument Type
NameCategories
General Oceanics GO-FLO water sampler  discrete water samplers
Instrument Mounting lowered unmanned submersible
Originating Country United Kingdom
Originator Dr Reg Uncles
Originating Organization Plymouth Marine Laboratory
Processing Status banked
Project(s) LOIS River-Atmosphere-Coast Study (RACS)
 

Data Identifiers

Originator's Identifier CH108C_CTD_PIGX_4:CTD12
BODC Series Reference 1686471
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1993-12-13 06:59
End Time (yyyy-mm-dd hh:mm) -
Nominal Cycle Interval -
 

Spatial Co-ordinates

Latitude 53.60295 N ( 53° 36.2' N )
Longitude 0.38220 E ( 0° 22.9' E )
Positional Uncertainty Unspecified
Minimum Sensor Depth 1.8 m
Maximum Sensor Depth 3.9 m
Minimum Sensor Height 22.2 m
Maximum Sensor Height 24.3 m
Sea Floor Depth 26.1 m
Sensor Distribution Unspecified -
Sensor Depth Datum Unspecified -
Sea Floor Depth Datum Instantaneous - Depth measured below water line or instantaneous water body surface
 

Parameters

BODC CODE Rank Units Short Title Title
ADEPZZ01 1 Metres DepBelowSurf Depth below surface of the water body
BOTTFLAG 1 Dimensionless C22_flag Sampling process quality flag (BODC C22)
CPHLFLP5 1 Milligrams per cubic metre chl-a_water>0.2um_fluor Concentration of chlorophyll-a {chl-a CAS 479-61-8} per unit volume of the water body [particulate >0.2um phase] by filtration, acetone extraction and fluorometry
PHAEFLP5 1 Milligrams per cubic metre Fluor_Phae_>0.2um Concentration of phaeopigments {pheopigments} per unit volume of the water body [particulate >0.2um phase] by filtration, acetone extraction and fluorometry
SAMPRFNM 1 Dimensionless SampRef Sample reference number
 

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

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

GO-FLO Bottle

A water sampling bottle featuring close-open-close operation. The bottle opens automatically at approximately 10 metres and flushes until closed. Sampling with these bottles avoids contamination at the surface, internal spring contamination, loss of sample on deck and exchange of water from different depths.

There are several sizes available, from 1.7 to 100 litres and are made of PVC with a depth rating of up to 500 m. These bottles can be attached to a rosette or placed on a cable at selected positions.

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

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) 1993-12-13
End Date (yyyy-mm-dd) 1993-12-13
Organization Undertaking ActivityUniversity of Plymouth Institute of Marine Studies (now University of Plymouth, School of Geography, Earth and Environmental Sciences)
Country of OrganizationUnited Kingdom
Originator's Data Activity IdentifierCH108C_CTD_CTD12
Platform Categorylowered unmanned submersible

BODC Sample Metadata Report for CH108C_CTD_CTD12

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
364397   10.00       16.80   18.10   17.60 Niskin bottle No problem reported    
364398   10.00        3.20    4.10    3.90 Niskin bottle No problem reported    
364399   10.00        1.30    1.80    1.80 General Oceanics GO-FLO water sampler 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.

Other Series linked to this Data Activity - 1285475

Cruise

Cruise Name CH108C
Departure Date 1993-12-11
Arrival Date 1993-12-23
Principal Scientist(s)Geoff Millward (University of Plymouth Institute of Marine Studies)
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
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