Metadata Report for BODC Series Reference Number 2125315

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

Data Category

Water sample data

Instrument Type

Name	Categories
Niskin bottle	discrete water samplers

Instrument Mounting

lowered unmanned submersible

Originating Country

Spain

Originator

Dr Pablo Serret

Originating Organization

University of Oviedo Department of Organism and Systems Biology

Processing Status

banked

Online delivery of data

Download available - Ocean Data View (ODV) format

Project(s)

UKSOLAS

Data Identifiers

Originator's Identifier	D338_CTD_DOXY_48:CTD_022
BODC Series Reference	2125315

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm)	2009-04-23 09:16
End Time (yyyy-mm-dd hh:mm)	-
Nominal Cycle Interval	-

Spatial Co-ordinates

Latitude	21.15429 N ( 21° 9.3' N )
Longitude	17.37892 W ( 17° 22.7' W )
Positional Uncertainty	0.05 to 0.1 n.miles
Minimum Sensor or Sampling Depth	5.0 m
Maximum Sensor or Sampling Depth	67.0 m
Minimum Sensor or Sampling Height	6.7 m
Maximum Sensor or Sampling Height	68.7 m
Sea Floor Depth	73.7 m
Sea Floor Depth Source	PEVENT
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 CODE	Rank	Units	Title
ADEPZZ01	1	Metres	Depth (spatial coordinate) relative to water surface in the water body
BOTTFLAG	1	Not applicable	Sampling process quality flag (BODC C22)
DOXYWITX	1	Micromoles per litre	Concentration of oxygen {O2 CAS 7782-44-7} per unit volume of the water body [dissolved plus reactive particulate phase] by Winkler titration
FIRSEQID	1	Dimensionless	Bottle firing sequence number
ROSPOSID	1	Dimensionless	Bottle rosette position identifier
SAMPRFNM	1	Dimensionless	Sample reference number

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
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

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.

Oxygen measurements for UK SOLAS cruise D338

Originator's Data Acquisition and Analysis

A total of 430 oxygen samples were collected from 46 CTD casts during D338. Samples were drawn from the Niskin bottles using silicone tubing, which was inserted into the bottom of each glass Oxygen bottle (nominal volume 125 ml). The sample bottle was allowed to overflow with several times its volume. The bottle was stoppered immediately, ensuring that no air was trapped inside.

Dissolved oxygen was determined by automated Winkler titration with photometric end-point detection (Carritt and Carpenter, 1966). The concentration of thiosulphate was calibrated every 2 days against potassium iodate standard.

References Cited

Carritt D.E. and Carpenter, J.H., 1966. Comparison and evaluation of currently employed modifications of the Winkler method for determining dissolved oxygen in seawater. A NASCO report. Journal of Marine Research, 24, 286-318.

BODC Data Processing Procedures

Data were received by BODC in a Microsoft Excel spreadsheet (D338_Oxygen_CTD_calibration.xls), which contained oxygen sample concentration and saturation along with the following metadata fields: longitude, latitude, cast and bottle number, depth, and oxygen saturation. The spreadsheet, which was used by the data originator to derive a calibration for the CTD in situ oxygen sensor, also contained coincidental CTD sensor oxygen from the bottle firing depths. CTD in situ sensor data are held separately from discrete sample data by BODC.

Parameter codes defined in the BODC parameter dictionary were mapped to the variables as follows:

Originator's Parameter	Units	Description	BODC Parameter Code	Units	Comments
O2W	µmol L^-1	Concentration of dissolved oxygen per unit volume of the water body by Winkler titration	DOXYWITX	µmol L^-1	n/a
n/a	µmol L^-1	Concentration standard deviation of dissolved oxygen per unit volume of the water body by Winkler titration	SDOXWITX	µmol L^-1	Oxygen standard deviation was computed by BODC for the few samples that were analysed in duplicate and had to be averaged prior to loading in the database.

The data were banked according to BODC standard procedures for discrete sample data. A few samples from CTD casts 042 and 046 were analysed in duplicate. BODC computed and banked the means and standard deviations of these data.

Data Quality Report

The originator flagged as suspect a small number (21) of the measurements. These flags were translated to the BODC quality control scheme and banked along with the data.

Users should be aware that some of the sampling depths supplied for cast 34 conflicted with those given, for the same bottle numbers, in both the cruise CTD log and the SeaBird files. This affected the top 6 bottles (rosette positions 7, 10, 13, 16, 21 and 24) in the upper 43 m. Variations in dissolved oxygen concentration in that depth range were small and the values could not be used to decide which source to trust. As a result and in consultation with the originators, BODC linked the data to the depth corresponding to the rosette position supplied.

Project Information

UK Surface Ocean Lower Atmosphere Study

The UK Surface Ocean Lower Atmosphere Study (UK SOLAS) is the UK's contribution to the international SOLAS programme.

UK SOLAS formed interdisciplinary teams to address three primary aims

To determine the mechanisms controlling rates of chemical transfer and improve estimates of chemical exchanges
To evaluate the impact of these exchanges on the biogeochemistry of the surface ocean and lower atmosphere and on feedbacks between the ocean and atmosphere
To quantify the impacts of these boundary layer processes on the global climate system

UK SOLAS started in 2003, to run for seven years. The programme was funded by the Natural Environment Research Council.

Funded projects

In total, 19 projects have been funded by UK SOLAS, over four funding rounds.

Project Title	Short Title	Principal Investigator
Impact of atmospheric dust derived material and nutrient inputs on near-surface plankton microbiota in the tropical North Atlantic	Dust	Eric Achterberg
The role and effects of photoprotective compounds in marine plankton	-	Steve Archer
Field observations of sea spray, gas fluxes and whitecaps	SEASAW	Ian Brooks
Factors influencing the biogeochemistry of iodine in the marine environment	-	Lucy Carpenter
Global model of aerosol processes - effects of aerosol in the marine atmospheric boundary layer	GLOMAP	Ken Carslaw
Ecological controls on fluxes of dimethyl sulphide (DMS) to the atmosphere	-	David Green
Dust outflow and deposition to the ocean	DODO	Ellie Highwood
Investigation of near surface production of iodocarbons - rates and exchanges	INSPIRE	Gill Malin
Reactive halogens in the marine boundary layer	RHaMBLe	Gordon McFiggans
The role of bacterioneuston in determining trace gas exchange rates	-	Colin Murrell
Measuring methanol in sea water and investigating its sources and sinks in the marine environment	-	Phil Nightingale
The impact of coastal upwellings on air-sea exchange of climatically important gases	ICON	Carol Robinson
The Deep Ocean Gas Exchange Experiment	DOGEE	Rob Upstill-Goddard
High wind air-sea exchanges	HiWASE	Margaret Yelland
Aerosol characterisation and modelling in the marine environment	ACMME	James Allan
3D simulation of dimethyl sulphide (DMS) in the north east Atlantic	-	Icarus Allen
Processes affecting the chemistry and bioavailability of dust borne iron	-	Michael Krom
The chemical structure of the lowermost atmosphere	-	Alastair Lewis
Factors influencing the oxidative chemistry of the marine boundary layer	-	Paul Monks

UK SOLAS has also supported ten tied studentships, and two CASE studentships.

Fieldwork

UK SOLAS fieldwork has included eight dedicated research cruises in the North Atlantic Ocean. Continuous measurements were made aboard aboard the Norwegian weather ship, Polarfront, until her decommission in 2009. Time series have been established at the SOLAS Cape Verde Observatory, and at the Plymouth Marine Laboratory L4 station. Experiments have taken place at the Bergen mesocosm facility.

A series of collaborative aircraft campaigns have added complementary atmospheric data. These campaigns were funded by UK SOLAS, African Monsoon Multidisciplinary Analyses (AMMA-UK), Dust and Biomass Experiment (DABEX) and the Facility for Airborne Atmospheric Measurements (FAAM).

Weblink: http://www.nerc.ac.uk/research/programmes/solas/

Data Activity or Cruise Information

Data Activity

Start Date (yyyy-mm-dd)	2009-04-23
End Date (yyyy-mm-dd)	2009-04-23
Organization Undertaking Activity	University of East Anglia School of Environmental Sciences
Country of Organization	United Kingdom
Originator's Data Activity Identifier	D338_CTD_CTD_022
Platform Category	lowered unmanned submersible

BODC Sample Metadata Report for D338_CTD_CTD_022

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

205422	20.00	1	1	67.40	67.70	67.10	Niskin bottle	No problem reported
205423	10.00	2	2	67.20	67.70	67.00	Niskin bottle	No problem reported
205424	20.00	3	3	67.40	67.70	67.10	Niskin bottle	No problem reported
205425	20.00	4	4	52.30	52.60	52.10	Niskin bottle	No problem reported
205426	20.00	5	5	52.10	52.50	52.00	Niskin bottle	No problem reported
205427	20.00	6	6	42.00	42.50	42.00	Niskin bottle	No problem reported
205428	20.00	7	7	42.00	42.40	41.90	Niskin bottle	No problem reported
205429	20.00	8	8	39.10	39.40	39.00	Niskin bottle	No problem reported
205430	20.00	9	9	38.90	39.30	38.90	Niskin bottle	No problem reported
205431	20.00	10	10	39.10	39.30	39.00	Niskin bottle	No problem reported
205432	20.00	11	11	22.10	22.40	22.10	Niskin bottle	No problem reported
205433	20.00	12	12	21.70	22.50	22.00	Niskin bottle	No problem reported
205434	20.00	13	13	17.00	17.30	17.00	Niskin bottle	No problem reported
205435	20.00	14	14	17.10	17.40	17.10	Niskin bottle	No problem reported
205436	20.00	15	15	14.00	14.40	14.10	Niskin bottle	No problem reported
205437	20.00	16	16	14.10	14.30	14.10	Niskin bottle	No problem reported
205438	20.00	17	17	9.80	10.20	9.90	Niskin bottle	No problem reported
205439	20.00	18	18	9.90	10.20	10.00	Niskin bottle	No problem reported
205440	10.00	19	19	6.60	7.10	6.80	Niskin bottle	No problem reported
205441	20.00	20	20	6.60	7.30	6.90	Niskin bottle	No problem reported
205442	20.00	21	21	4.80	5.20	5.00	Niskin bottle	No problem reported
205443	20.00	22	22	4.50	5.50	5.00	Niskin bottle	No problem reported
205444	20.00	23	23	4.60	5.40	5.00	Niskin bottle	No problem reported
205445	20.00	24	24	4.70	5.10	4.90	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	D338
Departure Date	2009-04-15
Arrival Date	2009-05-27
Principal Scientist(s)	Carol Robinson (University of East Anglia School of Environmental Sciences)
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