Offshore Physical Environmental Guidelines
Appendix I - Current Meter Metadata Report
Based on ICES Guidelines[9]
General
Raw and quality controlled data should, whenever possible, be stored at the original sampling frequency.
All parameters and units must be clearly specified and described. If parameter codes are used, then the source data dictionary must be specified. Parameter scales must be noted where applicable. If computed values are included, the equations used in the computations should be stated.
All relevant calibrations should be applied to the data including laboratory and field calibrations. Instrument calibration data should be included in the data file. The data should be fully checked for quality and flagged for erroneous values such as spikes, gaps, etc. An explicit statement should be made on the checks and edits applied to the data. If any data values have been removed, the times of the removed values should be noted.
In particular:
- All data values should be expressed in oceanographic terms, which should be clearly stated.
- Depending on the method of measurement, current velocity may be expressed in terms of speed and direction and/or in terms of east and north components.
- A clear statement should be made on whether or not the data have been corrected for magnetic variation - if the correction has been made then the magnetic variation that was assumed should be stored alongside the data.
- The time zone in use should be clearly stated and each data cycle should include date/time of observation (without loss of precision). It is recommended that UTC be used.
- Other parameters measured as part of the series, e.g. temperature, pressure, conductivity, should be included with the data.
- An estimate of uncertainty in the final data should be included.
A brief description of the data calibration, quality and processing (manufacturers and in-house) should be included and contain information regarding:
- Filtering, de-spiking, or smoothing methods
- Editing or quality control methods
- Interpolation techniques
- Adjustments made due to variations in calibration
Collection Details
Collection
- Country and organisation responsible for the deployment, recovery, collection and processing of the data. The name of the project leader should be included.
- Project, ship, mooring type, mooring number
- Originator's reference numbers/identifiers for mooring and series
- Dates and times of each instrument deployment and recovery (UTC)
- Dates and times of start and end of usable data for each instrument (UTC)
- Latitude and longitude, method of position fix (e.g. DGPS, GPS, etc.)
- Water column depth (specify method e.g. sounding, chart, etc.)
- Instrument depth (or height, specify which)
Mooring
- Brief description of mooring structure
- Performance of mooring including condition on recovery, whether dragged or damaged and any event that might have affected the data (e.g. wave action, knockdown, etc.)
Instrument - Conventional Moored
- Instrument description - manufacturer, instrument type, model, serial number, additional sensors
- Type of sampling (e.g. instantaneous, averaged, burst recording)
- Time interval between successive data cycles in the series
- Original sampling interval - for cases where the processed observation is derived/extracted from higher resolution data (optional)
- Accuracy, resolution and response range of individual sensors
- Standard of calibration, e.g. method, quality, dates, calibration coefficients
- Instrument modifications if any-
If applicable:
- Number of raw data samples used in processed value
- Methods of averaging, filtering or compression
Instrument - Moored ADCP
- Instrument description - manufacturer, instrument type, model, serial number, additional sensors, number of transducers
- Description of operational procedures including sampling interval (time between ensembles), pings per ensemble, bin size, number of bins, percentage good level, automated data rejection (e.g. fish rejection algorithms), etc.
- Frequency (kHz), band type (broad, narrow), heads facing upward or downward
- Parameters collected (e.g. u and v velocity components, vertical velocity, error velocity, echo intensity, percent good pings)
- Multiplicative and/or additive scale factors where applicable
- Instrument modifications if any
Report on data quality
Any additional information of use to secondary users which may have affected the data or have a bearing on its subsequent use (e.g. effects of near surface buoyancy, sea state, fouling, etc.)
- Date modified: