Metadata Report for BODC Series Reference Number 529208

• 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

Problem Reports

The wind direction data from this deployment are not valid. A rope caught on the direction vane during the deployment of the mooring. Comparison with concomitant wind direction data from met stations on the nearby Beryl and Frigg oil rigs shows that this incident hindered the good functioning of the met buoy wind direction sensor for the totality of the deployment.

Data Access Policy

Public domain 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.

The recommended acknowledgment is

"This study uses data from the data source/organisation/programme, provided by the British Oceanographic Data Centre and funded by the funding body."

Narrative Documents

Meteorological Buoy

The meteorological monitoring buoy consisted of a large surface toroid buoy secured at the sea floor by an anchor chain and surmounted by a light metal tower. The structure of the tower included a sail and a metal rail for instrument mountings (at an approximate distance of 2 m above sea surface).

Instrumentation

Aanderaa wind direction sensor 3590 (averaging) and buoy orientation sensor 2864

The wind direction sensor consists of a light wind vane mounted on a pivot on top of a housing. The housing is fitted with a built-in compass which is magnetically coupled to the vane. True wind speed measurement is obtained by combining measurements from the wind direction sensor and from the buoy orientation sensor.

Manufacturer's specifications for the wind direction sensor:

Manufacturer's specifications for the buoy orientation sensor:

Aanderaa wind speed sensor 2740

This sensor measures the average and maximum wind speed (gust) during the sampling interval. It consists of a three cup rotor on top of an aluminium housing. The rotor bearings consists of two stainless steel ball bearings protected by a surrounding skirt. The lower end of the skirt is furnished with a magnet. The magnet's rotation is sensed by a reed switch located into the housing. The sensor has two output signals: average and maximum wind speed (gust). The arithmetic mean of the wind is obtained regardless of sampling interval providing the sampling interval is between 4 seconds and 36 hours. The maximum wind speed is the highest speed occurring over a two-second period at any time during the sampling interval.

Manufacturer's specifications:

Aanderaa relative humidity sensor 3445

This sensor consists of a RH probe (model 3447) protected from direct sunshine and rains by a radiation screen.

Manufacturer's specifications:

Aanderaa air temperature sensor 3455

This sensor consists of a platinum resistance thermometer protected from heating by direct sunshine by a radiation screen.

Manufacturer's specifications:

Aanderaa solar radiation sensor 2770

This sensor measures incoming solar and sky radiations. The sensor employs a high sensitivity thermistor bridge which measures the temperature rise of a black surface under a borosilicate glass dome.

Manufacturer's specifications:

Aanderaa net radiation sensor 2811 (Pyrradiometer)

This sensor measures the difference between incoming and outgoing radiation (both sunlight and infrared) at the Earth's surface. The sensor consists of a radiation detector composed of two surfaces which absorb/emit radiation, inside an aluminium housing covered at one end by a teflon dome. One surface is exposed to radiation and the other is shielded inside the sensor housing. A thermistor-resistor network senses the temperature difference between the two surfaces of the detector giving a measure of net radiation.

Manufacturer's specifications

Data Quality Notes

From the start of the record to 01 October 1998, the wind speed values were generally low compared to wind speeds recorded by the weather stations on the Beryl and Frigg oil platforms. When excessive differences were observed, the wind speed recorded by the sensor on the met buoy was flagged as suspect. After 01 October 1998 the three records show good agreement.

Meteorological Buoy Data Processing

Data Originator's Processing

Raw data readings were converted to engineering units using factory calibrations. The calibration equations applied were as follow:

• Wind speed (m/s)= 0.0746 N + 0.4
• Wind direction (°M)= 0.349 N + 1.5
• Air temperature (°C)= 0.08042 N + 9.864 E-6 N² - 43.06
• Relative humidity (%)= 0.1026 N - 2.36
• Net radiation (W/m²)= 4.098 N - 209.8
• Solar radiation (W/m²)= 4.202 N - 2168

where N is the datalogger reading.

BODC's Data Processing and Quality Control

BODC screen both the series header information and the parameter values in the data cycles.

Header information is inspected for:

1. Irregularities such as suspect values.
2. Inconsistencies between related information, for example:
   • Times for mooring deployment and for start/end of data series.
   • Length of record or number of data cycles, the cycle interval, the clock error and the period over which accrued.
   • Parameters expected and the parameters actually present in the data cycles.
3. Originator's comments on meter/mooring performance and data quality.

Documents are written by BODC highlighting irregularities which cannot be resolved.

Data cycles are inspected using time series plots of all parameters. Values suspected of being of unnatural origin may be tagged with BODC flag for suspect value.

Project Information

PROcesses of Vertical Exchange in Shelf Seas (PROVESS)

Introduction

PROVESS was an interdisciplinary study of the vertical fluxes of properties through the water column and the surface and bottom boundary layers. The project was funded by the European Community MAST-III programme (MAS3-CT97- 0159) and ran from March 1998 to May 2001.

Scientific Rationale

PROVESS was based on the integration of experimental, theoretical and modelling studies with the aim of improving understanding and quantification of vertical exchange processes in the water column, in particular in the surface and benthic boundary layers and across the> pycnocline. PROVESS also explored mechanisms of physical-biological coupling in which vertical exchanges and turbulence significantly affect the environmental conditions experienced by the biota with particular reference to aggregation, flocculation, sedimentation and trophic interactions.

Fieldwork

The experimental phase of the project was carried out at two contrasting sites in the North Sea: the northern North Sea site (NNS) and the southern North Sea site (SNS).

The two sites had the following characteristics:

At both locations measurements were concentrated at a central position with additional measurements being made to estimate horizontal gradients. Moored instruments (including current meters, temperature and pressure sensors, fluorometers, transmissometers, nutrient analysers and meteorological sensors) were deployed between 7 September and 5 November 1998 at the NNS and between 29 March and 25 May 1999 at the SNS. Each experiment was supported by intensive measurement series made from oceanographic ships and involving turbulence dissipation profiler CTD, particle size profilers, optical profilers, benthic sampling and water bottle sampling.

Details of the cruises were as follows:

Data Activity or Cruise Information

Data Activity

PROVESS Project POLRIG#796

This mooring was also known within PROVESS as 'Rig G'. It was one of a cluster of moorings deployed at the main focus of the Northern North Sea Site in the autumn of 1998. The rig was deployed by FS Valdivia (cruise #174) in September 1998 and recovered by RRS Challenger (cruise #140) in October/November 1998.

Notes:

1. All sensors and loggers owned by Nederlands Instituut voor Onderzoek der Zee (NIOZ), Texel, Netherlands.
2. Wind direction fin caught up in grappler rope for all of the deployment.
3. Complementary met data also available from the Beryl and Frigg oil rig meteorological stations ( 59° 33.99' N 01°32.00' E and 59° 54.00' N 02° 06.00' E respectively).

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

PROVESS Northern North Sea Site

Nineteen mooring packages were deployed at PROVESS Northern North Sea site during the cruise Valdivia VA174 in September 1998. The layout of the mooring assemblage was L-shaped. It consisted of an heavily-instrumented site centred close to 59° 20' N, 1° 00'E (Site A with rigs A, B, Ca/b, D, E, Fa/b, G, H, I, J1, J2 and L) and secondary single-rig sites extending up to 40 km north (V and Y) and east (U and X). An addition mooring package, NIOZ or Rig M, was also deployed at Site A during the RV Pelagia PE125 cruise in October 1998.

Rigs Ca/b and Fa/b were two short-term rigs which were recovered at the end of the cruise VA174 and redeployed during the cruise Challenger CH140 in October. All the other rigs were recovered during the cruise CH140 in October-November 1998 apart from rigs H and L which could not be found and rig Cb which was trawled and recovered from Peterhead (Scotland).

The layout of the mooring array was:

Mooring data

The data returned from each rig were as follows:

CTD data

A total of 352 CTD casts were also collected during the four cruises surveying this area. These include:

Additonal data

Complementary meteorological and sea state data for PROVESS Northern North Sea Experiment were obtained from Marine Weather Stations located on Beryl and Frigg oil platforms in the Northern North Sea.

Related Fixed Station activities are detailed in Appendix 1

BODC Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

SeaDataNet Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

Appendix 1: PROVESS Northern North Sea Site

Related series for this Fixed Station are presented in the table below. Further information can be found by following the appropriate links.

If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.