Metadata Report for BODC Series Reference Number 964211

• 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

No Problem Report Found in the Database

Data Access Policy

SIMORC data access conditions

The data collated and held at BODC on behalf of the SIMORC project are restricted. However, the data will be available to download from the Official SIMORC Website, as part of the project protocol. The data set will initially include data from the oil companies TOTAL, Shell and BP.

Narrative Documents

BODC Processing

Data were received by BODC in Matlab format. They were then reformatted to QXF format using BODC transfer function 390. The following table shows how the variables within the files were mapped to the appropriate BODC parameter codes:

Following transfer to QXF, the data were screened using BODC's in-house visualisation software, EDSERPLO.

Originator's Data Processing

Data processing

Data were imported into Matlab for the following processing:

• The record was truncated to exclude times pre and post deployment.
• Time was recorded in GMT.
• Wind speeds were converted from knots to meters per second.
• Wind speeds were corrected to a common elevation of 40 meters using a simple logarithmic profile calculated in WAG phase one. This gives wind speed U(z) at elevation z as proportional to ln(z/z₀) where z₀ is the roughness length. Z₀ was calculated from the Nnwa data as 3.2 X 10^-4, which gave the following conversion factors:

  Location	Elevation	Correction Factor
  Moho	51	0.98
  Dalia	60	0.97

  Gust factors are not affected by this correction as they cancel out.
• Wind direction data was compared at the two locations to check reliability. This showed only a small offset, attributable to the difference in location. Therefore, no further offset was applied.

General Data Screening carried out by BODC

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

Header information is inspected for:

• Irregularities such as unfeasible values
• Inconsistencies between related information, for example:
  • Times for instrument deployment and for start/end of data series
  • Length of record and the number of data cycles/cycle interval
  • Parameters expected and the parameters actually present in the data cycles
• 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 or depth series plots of all parameters. Currents are additionally inspected using vector scatter plots and time series plots of North and East velocity components. These presentations undergo intrinsic and extrinsic screening to detect infeasible values within the data cycles themselves and inconsistencies as seen when comparing characteristics of adjacent data sets displaced with respect to depth, position or time. Values suspected of being of non-oceanographic origin may be tagged with the BODC flag denoting suspect value; the data values will not be altered.

The following types of irregularity, each relying on visual detection in the plot, are amongst those which may be flagged as suspect:

• Spurious data at the start or end of the record.
• Obvious spikes occurring in periods free from meteorological disturbance.
• A sequence of constant values in consecutive data cycles.

If a large percentage of the data is affected by irregularities then a Problem Report will be written rather than flagging the individual suspect values. Problem Reports are also used to highlight irregularities seen in the graphical data presentations.

Inconsistencies between the characteristics of the data set and those of its neighbours are sought and, where necessary, documented. This covers inconsistencies such as the following:

• Maximum and minimum values of parameters (spikes excluded).
• The occurrence of meteorological events.

This intrinsic and extrinsic screening of the parameter values seeks to confirm the qualifying information and the source laboratory's comments on the series. In screening and collating information, every care is taken to ensure that errors of BODC making are not introduced.

Project Information

System of Industry Metocean data for the Offshore and Research Communities (SIMORC)

The EU-funded SIMORC project is a collaborative effort between MARIS (Netherlands), BODC (UK), the International Association of Oil and Gas Producers (OGP) and IOC-IODE to provide a harmonised and quality controlled metocean data set from data collected by oil and gas producers, accessible through the SIMORC protocol.

Data Activity or Cruise Information

Data Activity

SIMORC Meteorological Station Congo Moho

The position of the met station was 5.28° S; 11.38° E at a height of approximately 60 metres above MSL.

The Vaisala Maritime Automatic Weather Station was deployed on behalf of TOTAL at Congo Moho and consisted of the following instruments.

Where MSL = Mean Sea Level

Related Data Activity activities are detailed in Appendix 1

Fixed Station Information

Fixed Station Information

SIMORC: TOTAL Congo Moho Fixed Station Document

This site consists of a Floating Production Unit (FPU), located in the Moho field, offshore Congo. Various deployments were taken from or near this site:

• A Vaisala Maritime Automated Weather Station (MAWS) recorded wind and meteorological data from 28th May 2008 to 31st March 2009.
• A Datawell Waverider buoy was deployed from 19th June 2009 to 14th July 2009.
• Two RDI instruments ADCPs and an Aanderaa RCM7 current meter were deployed from 16th June 2009 to 26th November 2009.

The nominal position of the site is 5.28° S; 11.38° E with an assumed water depth (taken from GEBCO) of 865 metres.

Related Fixed Station activities are detailed in Appendix 2

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: Moho2min

Related series for this Data Activity 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.

Appendix 2: Moho, Congo

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.