Metadata Report for BODC Series Reference Number 952989


Metadata Summary

Data Description

Data Category Meteorology -unspecified
Instrument Type
NameCategories
Chelsea Technologies Group 2-pi PAR irradiance sensor  radiometers
Global Positioning Satellite System  NAVSTAR Global Positioning System receivers
Instrument Mounting research vessel
Originating Country United Kingdom
Originator Dr Alan Morris
Originating Organization Plymouth Marine Laboratory
Processing Status banked
Project(s) LOIS River-Atmosphere-Coast Study (RACS)
 

Data Identifiers

Originator's Identifier CH99_MET
BODC Series Reference 952989
 

Time Co-ordinates(UT)

Start Time (yyyy-mm-dd hh:mm) 1992-12-07 09:15
End Time (yyyy-mm-dd hh:mm) 1992-12-20 08:14
Nominal Cycle Interval 30.0 seconds
 

Spatial Co-ordinates

Southernmost Latitude 49.91617 N ( 49° 55.0' N )
Northernmost Latitude 55.91933 N ( 55° 55.2' N )
Westernmost Longitude 5.86933 W ( 5° 52.2' W )
Easternmost Longitude 2.30500 E ( 2° 18.3' E )
Positional Uncertainty 0.05 to 0.1 n.miles
Minimum Sensor Depth -
Maximum Sensor Depth -
Minimum Sensor Height -
Maximum Sensor Height -
Sea Floor Depth -
Sensor Distribution -
Sensor Depth Datum -
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)
ALATGP01 1 Degrees Lat_GPS Latitude north (WGS84) by unspecified GPS system
ALONGP01 1 Degrees Lon_GPS Longitude east (WGS84) by unspecified GPS system
IRRDSS01 1 MicroEinsteins per square metre per second SurfSPAR Downwelling 2-pi scalar irradiance as photons (PAR wavelengths) in the atmosphere by 2-pi scalar 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


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

Chelsea Technologies Photosynthetically Active Radiation (PAR) Irradiance Sensor

This sensor was originally designed to assist the study of marine photosynthesis. With the use of logarithmic amplication, the sensor covers a range of 6 orders of magnitude, which avoids setting up the sensor range for the expected signal level for different ambient conditions.

The sensor consists of a hollow PTFE 2-pi collector supported by a clear acetal dome diverting light to a filter and photodiode from which a cosine response is obtained. The sensor can be used in moorings, profiling or deployed in towed vehicles and can measure both upwelling and downwelling light.

Specifications

Operation depth 1000 m
Range 2000 to 0.002 µE m -2 s -1
Angular Detection Range ± 130° from normal incidence
Relative Spectral Sensitivity

flat to ± 3% from 450 to 700 nm

down 8% of 400 nm and 36% at 350 nm

Further details can be found in the manufacturer's specification sheet .

Global Positioning Satellite System

A location system of unspecified make or model that determines location on the Earth's surface using the Global Positioning Satellite Network. Angular co-ordinates are given relative to WGS84 CRS. Other parameters such as platform velocity may be derived from this.

CH99 Sea surface meteorological instrument details

Meteorological parameters were recorded by a suite of instruments onboard the ship. The PAR meters were recorded as voltages and calibrated to µE m 2 by BODC using coefficients determined in February 1990. Instrument details are given in the table below.

Instrument type Make and model
GPS unspecified
Radiometer Chelsea Instruments 2π

CH99 Meteorology Processing Notes

Photosynthetically Active Radiation (PAR)

PAR scalar irradiance was measured using PML 2π PAR sensors mounted on gimballed supports on each side of the ship's monkey island. This arrangement ensured that when one sensor was in shadow, the other was not.

The data from the PAR meters were recorded as voltages and calibrated to units of µE m -2 s -1 by BODC using coefficients determined in February 1990. The calibration equations used were:

Port: PAR(µE m -2 s -1 )= exp (4.996*volts + 6.7545) * .0375
Starboard: PAR(µE m -2 s -1 )= exp (5.080*volts + 6.8461) * .0375

After spikes had been flagged out, a merged PAR channel was produced by taking the maximum of the port and starboard values to eliminate shading effects.

CH99 Sea surface Hydrography, Meteorology and Navigation Series

Instrumentation

Seawater was continuously pumped from the hull of the ship (at a depth of about 4m) through the various underway sensors on-deck and in the lab. This is known as the ship's non-toxic supply. An outlet of this, situated in the ship's wet laboratory, was used to collect the calibration samples for the underway sensors.

Data Acquisition

For most parameters, data logging and initial processing was handled by the RVS ABC system. The Level A sampling microcomputer digitised an input voltage, applied a time stamp and transferred the data via the Level B disk buffer onto the Level C where the data records were assembled into files. Sampling rates varied from 10 seconds to several minutes. The Level C included a suite of calibration software, which was used to apply initial calibrations to convert raw ADC counts into engineering units. At the end of the cruise the Level C disk base was transferred to BODC for further processing.

BODC Data Processing Procedures

Data from the underway files were merged into a common file (the binary merge file) using time as the primary linking key. Data logged as voltages (e.g. PAR, nutrients) were converted to engineering units. Each data channel was inspected on a graphics workstation and any spikes or periods of dubious data were flagged. The power of the workstation software was used to undertake all possible comparative-screening checks between channels.


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

Cruise

Cruise Name CH99
Departure Date 1992-12-07
Arrival Date 1992-12-21
Principal Scientist(s)Alan W Morris (Plymouth Marine 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
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