Metadata Report for BODC Series Reference Number 1224468


Metadata Summary

Data Description

Data Category Meteorology -unspecified
Instrument Type
NameCategories
TriOS RAMSES ACC-UV Hyperspectral UVA and UVB Radiometer  radiometers
Instrument Mounting research vessel
Originating Country United Kingdom
Originator Dr Tim Smyth
Originating Organization Plymouth Marine Laboratory
Processing Status banked
Project(s) Oceans 2025 Theme 10 SO1:AMT
 

Data Identifiers

Originator's Identifier UV_LATLON_091014
BODC Series Reference 1224468
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 2009-10-14 00:03
End Time (yyyy-mm-dd hh:mm) 2009-10-14 18:20
Nominal Cycle Interval 300.0 seconds
 

Spatial Co-ordinates

Start Latitude 49.65980 N ( 49° 39.6' N )
End Latitude 49.26950 N ( 49° 16.2' N )
Start Longitude 7.44820 W ( 7° 26.9' W )
End Longitude 11.81450 W ( 11° 48.9' W )
Positional Uncertainty 0.0 to 0.01 n.miles
Minimum Sensor Depth -15.0 m
Maximum Sensor Depth -15.0 m
Minimum Sensor Height -
Maximum Sensor Height -
Sea Floor Depth -
Sensor Distribution Fixed common depth - All sensors are grouped effectively at the same depth which is effectively fixed for the duration of the series
Sensor Depth Datum Approximate - Depth is only approximate
Sea Floor Depth Datum -
 

Parameters

BODC CODE Rank Units Short Title Title
AADYAA01 1 Days Date(Loch_Day) Date (time from 00:00 01/01/1760 to 00:00 UT on day)
AAFDZZ01 1 Days Time(Day_Fract) Time (time between 00:00 UT and timestamp)
ACYCAA01 1 Dimensionless Record_No Sequence number
ALATGP01 1 Degrees Lat_GPS Latitude north (WGS84) by unspecified GPS system
ALONGP01 1 Degrees Lon_GPS Longitude east (WGS84) by unspecified GPS system
VSRAUVAW 1 Watts per square metre DWIrr_UVA Downwelling vector irradiance as energy (ultra-violet A wavelengths) in the atmosphere by cosine-collector radiometer
VSRAUVBW 1 Watts per square metre DWIrr_UVB Downwelling vector irradiance as energy (ultra-violet B wavelengths) in the atmosphere by cosine-collector radiometer
 

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

AMT19 RRS James Cook (JC039) Surface UV Measurements Data Quality Report

The clocks changed on AMT19 from GMT to GMT -1 on 25th October 2009 at 02:00. This effects the raw data but not the processed UVA and UVB calculations.

The data were calibrated by Trios in March 2009.


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

AMT19 RRS James Cook (JC039) Surface UV Instrumentation

Instrument Serial number Parameter
Trios Rameses ACC UV SAM_81a2 UVA and UVB

TriOS RAMSES-ACC-UV radiometer

Basic Information

This is a spectral radiometer measuring over the UV band range (280-500 nm) with a cosine-response to measure irradiance. It is fitted with a 256 channel silicon photodiode array with channels giving 2.2 nm/pixel and a spectral accuracy of 02 nm. Typical saturation (4ms integration time) is 20 W m-2 nm-1 sr-1 (at 300 nm), 17 W m-2 nm-1 sr -1 (at 360nm), 18W m-2 nm-1 sr -1 (at 500nm). Typical NEI (8ms integration time) is 0.85 µW m-2 nm-1 sr -1 (at 300nm), 0.75 µW m-2 nm-1 sr -1 (at 360nm), 0.80 µW m-2 nm-1 sr -1 (at 500nm). Acuuracy is quoted as being better than 6-10 per cent depending on spectral range.

Performance Specifications

Optics

wavelength range* 280 - 500 nm
detector type* 256 channel silicon photodiode array
spectral sampling*: 2.2 nm/pixel
spectral accuracy: 0.2 nm
usable channels: 100
typical saturation (4ms integration time): 20 W m -2 nm -1 sr -1 (at 300nm)
17 W m -2 nm -1 sr -1 (at 360nm)
18 W m -2 nm -1 sr -1 (at 500nm)
typical NEI (8ms integration time): 0.85 µW m -2 nm -1 sr -1 (at 300nm)
0.75 µW m -2 nm -1 sr -1 (at 360nm)
0.80 µW m -2 nm -1 sr -1 (at 500nm)

Detection

collector type: cosine response
accuracy: better than 6-10% (depending on spectral range)

Electrical

integration time: 4 ms - 8 sec (user selectable or auto [4 ms - 4096 ms])
telemetry data interface: RS232 or Serial Bus
data rate (RS232): 1,200 - 19,200 baud
power requirements: 1.5 - 11 VDC
0.85mW (data acquisition active)
100mW (interface active)
0.5mW (stand-by modus)
connector: SubConn micro 5 pin male

Physical

size: dia. 4.83 cm x 26 cm (without connector)
weight in air: <1.0 kg (stainless steel / POM housing)
depth range: 300m
operating temperature: -10°C to +50°C

* specifications from Carl ZEISS, Germany

Further information may be found in the TriOS RAMSES brochure .

AMT19 RRS James Cook (JC039) Surface UV Measurements Data Processing Document

Originator's Processing

The UV hyperspectral measurements were taken on the superstructure of the RRS James Cook during AMT-19. The measurements were taken every 5 minutes during daylight hours for the duration of the cruise.

The individual acquisitions with filenaming 224d_yyyy-mm-dd_HH-MM-SS_nnn_nnn.dat (where yyyy is the year, mm the month, dd the day, HH the hour, MM the month, SS the second and nnn an obsolete identifier from the Trios database. Within the file there is a header describing the data (first 43 lines) followed by the hyperspectral data. The nominal wavelength interval is around 2 nm but varies. The first column is the wavelength (nm) and the second UV light intensity (mW/(m^2 nm)). The third and fourth columns are measures of error and sensor status (not used in general).

The data were fully calibrated using a calibration carried out by Trios in March 2009.

Using the idl routine trios_uv_deck.pro the hyperspectral data were split into UVA and UVB components and put into daily files with the naming convention yymmdd_uva_uvb.txt. These text files were subsequently submitted to BODC alongside the raw .dat files.

N.B. The clocks changed on AMT-19 erroneously from GMT to GMT - 1 on 25th October 2009 at 02.00. This effects the raw data files but not the UVA and UVB calculations.

BODC Processing

The data were received and archived to the BODC system. Due to the lack of longitude and latitude in the originator's files the underway latitude and longitude in the BODC bank were concatenated with the UV files. No data existed in the files on the 23/10/2009, 24/10/2009, 25/10/2009 and 29/11/2009. The data were then transferred to the BODC format and loaded to the database.

Parameters

Parameter codes defined in the BODC parameter dictionary were assigned to the variables as shown in the table below:

Originator's Parameter Originator's Units BODC Parameter Code BODC Parameter Units BODC Description
UVA W/(m^2) VSRAUVAW Watts per square metre Downwelling vector irradiance as energy (ultra-violet A wavelengths) in the atmosphere by cosine-collector radiometer
UVB W/(m^2) VSRAUVBW Watts per square metre Downwelling vector irradiance as energy (ultra-violet B wavelengths) in the atmosphere by cosine-collector radiometer
N/A N/A ALATGP01 Degrees Latitude north (WGS84) by unspecified GPS system
N/A N/A ALONGP01 Degrees Longitude east (WGS84) by unspecified GPS system

Screening

The data was screened using the BODC in-house software, Edserplo. The data was screened with no flags applied.


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:

The specific objectives are:

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 JC039 (AMT19, JC040)
Departure Date 2009-10-13
Arrival Date 2009-12-01
Principal Scientist(s)Andrew Rees (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

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