Metadata Report for BODC Series Reference Number 2206724

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

Atmospheric composition

Instrument Type

Name	Categories
Thermo Fisher Scientific 49i ozone analyser	atmospheric gas analysers

Instrument Mounting

research vessel

Originating Country

United Kingdom

Originator

Dr Katie Read

Originating Organization

University of York Department of Chemistry

Processing Status

banked

Online delivery of data

Download available - Ocean Data View (ODV) format

Project(s)

Oceans 2025 Theme 10 SO1:AMT

Data Identifiers

Originator's Identifier	AMT22_O3
BODC Series Reference	2206724

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm)	2012-10-10 18:01
End Time (yyyy-mm-dd hh:mm)	2012-11-20 19:30
Nominal Cycle Interval	60.0 seconds

Spatial Co-ordinates

Southernmost Latitude	47.09390 S ( 47° 5.6' S )
Northernmost Latitude	50.23580 N ( 50° 14.1' N )
Westernmost Longitude	54.70630 W ( 54° 42.4' W )
Easternmost Longitude	3.12350 W ( 3° 7.4' W )
Positional Uncertainty	0.0 to 0.01 n.miles
Minimum Sensor or Sampling Depth	-19.4 m
Maximum Sensor or Sampling Depth	-17.1 m
Minimum Sensor or Sampling Height	-
Maximum Sensor or Sampling Height	-
Sea Floor Depth	-
Sea Floor Depth Source	-
Sensor or Sampling Distribution	Unspecified -
Sensor or Sampling Depth Datum	Approximate - Depth is only approximate
Sea Floor Depth Datum	-

Parameters

BODC CODE	Rank	Units	Title
AADYAA01	1	Days	Date (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ01	1	Days	Time (time between 00:00 UT and timestamp)
ACYCAA01	1	Dimensionless	Sequence number
ALATGP01	1	Degrees	Latitude north relative to WGS84 by unspecified GPS system
ALONGP01	1	Degrees	Longitude east relative to WGS84 by unspecified GPS system
O3XXA254	1	Parts per billion by volume	Concentration of ozone {O3 CAS 10028-15-6} per unit volume of the atmosphere [gaseous phase] by in-situ UV absorption spectrometer

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

Continuous atmospheric ozone

59,130 cycles were obtained in total for continuous atmospheric ozone (O3XXA254) measurements along cruise AMT22. The originator flagged at least 32% of cycles as 'probably bad data (reduced quality due to missing ship/wind data)' or 'bad data (reduced quality due to ship influence)'. The quality control flag 'L' has been applied to these values as they were considered suspect by the originator. Values flagged as 'probably good data (reduced quality due to operating conditions)' and 'good data' by the originator have not been flagged by BODC. At least 5% of cycles were flagged as 'changed (missing/removed)' by the originator. These values have been flagged 'N' by BODC.

The wind and ship data the originator used to flag reduced quality data (originator's flag 3 / 4, BODC flag 'L') did not always align exactly. The originator specified there is a likely error margin of + / − 0.5 minutes, so care should be taken with the data points surrounding flagged data.

Continuous atmospheric ozone data were recorded by the following instrument: Scientific 49i ozone analyser.

JC079 (AMT22) continuous atmospheric ozone measurements Data Quality Report

59,130 cycles were obtained in total for continuous atmospheric ozone (O3XXA254) measurements along cruise AMT22.

The originator flagged at least 32% of cycles as 'probably bad data (reduced quality due to missing ship/wind data)' or 'bad data (reduced quality due to ship influence)'. The quality control flag 'L' has been applied to these values as they were considered suspect by the originator. Values flagged as 'probably good data (reduced quality due to operating conditions)' and 'good data' by the originator have not been flagged by BODC.

At least 5% of cycles were flagged as 'changed (missing/removed)' by the originator. These values have been flagged 'N' by BODC.

Continuous atmospheric ozone data were recorded by the following instrument: Scientific 49i ozone analyser.

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

Thermo Scientific Ozone analyser 49i

The Ozone analyser model 49i is a dual cell photometer ozone analyser that uses UV photometric technology to measure the amount of ozone in the air. The instrument allows for dual and auto range and allows for the sample and reference flowing at the same time. Temperature and pressure correction are available as a standard feature. The measuring range spans 0.05 ppb to 200 ppm.

General specifications are presented in the table below:

Parameter	specs
Preset ranges	0-0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, 100 and 200 ppm 0-0.1, 0.2, 1, 2, 5, 10, 20, 50, 100, 200 and 400 mg m^-3
custom ranges	0-0.05 to 200 ppm 0-0.1 to 400 mg m^-3
Zero noise	0.25 ppb RMS (60 s averaging time)
Lower detectable limit	0.50 ppb
Zero drift (24 hours)	<1.0 ppb
Span drift	<1% full scale per month
Response time	20 s (10 s lag time)
Precision	1.0 ppb
Linearity	±1% full scale
Sample flow rate	1-3 l min^-1

Further information can be found in the manufacturer data sheet.

JC079 (AMT22) continuous atmospheric ozone measurements Instrumentation

The air sample inlet was situated on the monkey island of the ship. Atmospheric ozone levels were measured with a UV photometric ozone analyser (Thermo Electron Corporation, Model 49i). The height of the inlet was not specified by the originator, the depth of this has been estimated by BODC as a minimum of -19.4 m and a maximum of -17.1 m.

Please see the JC079 cruise report for further information.

Ozone was measured with the following scientific sensors:

Sensor	Serial Number	Calibration Date	Comments
Thermo Scientific Model 49i Ozone Analyzer	-	-	No information for serial number or calibration date.

Continuous atmospheric ozone measurements: JC079 (AMT22) Originator Data Processing

Atmospheric ozone was measured during the RRS James Cook cruise JC079 (AMT22), from the 10^th of October 2012 to the 20^th of November 2012. This was from Southampton (UK) to Punta Arenas (Chile).

The air sample inlet was situated on the monkey island of the ship. Atmospheric ozone levels were measured with a UV photometric ozone analyser (Thermo Electron Corporation, Model 49i) along the cruise track, from the same air inlet as the GC-MS air samples. The height of the inlet was not specified by the originator, the depth of this has been estimated by BODC as a minimum of -19.4 m and a maximum of -17.1 m.

Data (10 s resolution raw data) were averaged to 1 minute resolution by a data recording programme (DAQFactory) alongside several instrument operating parameters. The instrument was calibrated at regular intervals in the lab between campaigns. Constant concentration data (using an ozone calibrator) from before the start of the cruise was used to calculate the precision on the data (sqrt(2sigma)), giving 1.9 ppbv.

Please see the JC079 cruise report for further detail of originators processing.

JC079 (AMT22) continuous atmospheric ozone measurements BODC Processing

Atmospheric ozone was measured during the RRS James Cook cruise JC079 (AMT22), from the 10^th of October 2012 to the 20^th of November 2012. This was from Southampton (UK) to Punta Arenas (Chile). The air sample inlet was situated on the monkey island of the ship. Atmospheric ozone levels were measured with a UV photometric ozone analyser (Thermo Electron Corporation, Model 49i) along the cruise track, from the same air inlet as the GC-MS air samples. The height of the inlet was not specified by the originator, the depth of this has been estimated by BODC as a minimum of -19.4 m and a maximum of -17.1 m. The atmospheric ozone data were supplied to BODC in .csv format and converted to the BODC internal format.

JC079 cruise report

During transfer, the originator's variables were mapped to unique BODC parameter codes. The following table shows the parameter mapping:

Originators variable	Originators Units	BODC Code	BODC Units	Comments
O3 [ppbv]	ppbv	O3XXA254	Parts per billion by volume	Measured continuously throughout the cruise.
Latitude [deg+veN]	Deg	ALATGP01	Degrees	-
Longitude [deg+veE]	Deg	ALONGP01	Degrees	-

Following transfer the data were screened using BODC in-house visualisation software.

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

Cruise

Cruise Name	JC079 (AMT22)
Departure Date	2012-10-10
Arrival Date	2012-11-24
Principal Scientist(s)	Glen A Tarran (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