Metadata Report for BODC Series Reference Number 194768

• 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

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

Munro Float Tide Gauge

The Munro gauge measures the sea level by means of a float in a stilling well. The float is about 45cm diameter - the large diameter reduces inevitable errors in buoyancy due to friction of the gearing and small changes in the length of float wire. This wire is coiled round a drum on the end of the gauge and another drum contains the counter balance wire.

The drum is geared to a slotted tape attached to a pen carriage which travels the chart during the rise and fall of the tide.

Tide Gauge Data Processing by IOS Tidal Computation Section

Data processing takes place in 3 stages:

1. Hourly digitizing of the chart record, followed by an assessment of gauge errors, by continuity checks and correlating with gauge operator's remarks, if any.

2. Data are processed through the IOS Tidal Elevation Reduction Package (TERP) incorporating error findings. Checks include identifying gaps in the data , flagging errors notified in the form filling stage, checking for smoothness of hourly data by difference methods and curve fitting. Suspect values are listed. Interactive editing may be carried out to correct spikes or to modify time or datum errors.

3. Check that the editing has been carried out with the added assistance of predicted values. This is used particularly to confirm the time error applicatiion.

Note: Data processed prior to 1979 has had known timing errors corrected for manually.

Reference

Ovadia,D.C. and Graff,J.
Tidal Reduction Elevation Package (TERP) Software Description and Systems Specification. March 1981

Project Information

UK Tide Gauge Network

The national network of 'Class A' sea level gauges are deployed at 47 sites around the coast of the U.K.

The network was established after the serious flooding of the Thames estuary in 1953, which resulted from a violent storm in the North Sea.

The network sets out to obtain high quality tidal information through telemetry and provide warning of any possible flooding of coastal locations around the British Isles.

Data Activity or Cruise Information

No Data Activity or Cruise Information held for the Series

Fixed Station Information

Fixed Station Information

Aberdeen (Scotland) Site History

History Summary

Benchmark descriptions

Benchmark relationships

TGZ = Admiralty Chart Datum (ACD)
TGZ = 2.25m below Ordnance Datum Newlyn (ODN)
TGZ = 6.318m below TGBM

Note: Please also see document 83020

Datum information

For pre 1980 data, the heights have been adjusted by the data relative to ACD values, so that all data are now referred to Admiralty Chart Datum.

Corrected Timing Errors

The table below lists the notified time errors for which corrections have been made (if the time error is positive the clock was fast, and if negative the clock was slow.)

Uncorrected Timing Errors

1946 - Timing problems remain during 28-29 May, Nov and Dec.

1947 - Major timing problems during 3-4 Jan and 16-17 Nov. Also during Mar, 14-20 Aug, 12-14 Oct and 28 Nov-1 Dec.

1948 - The timing looks suspect during 25 Feb, 29 Feb, 10-13 May, 20-22 Jun and 14 Oct onwards.

1949 - There are also timing problems during May and June.

1954 - The timing looks highly suspect with an apparent error of -30 mins.

1956 - The timing looks highly suspect with an apparent error of -30 mins.

1957 - Timing is suspect during Feb, May, Jun, Jul, 24-28 Aug, 22-26 Nov, 12-13 Dec, 20-25 Dec.

1958 - Timing is suspect during 19-24 Jan, 5-9 Mar, 14-22 Jul, 11-17 Dec, 7-9 May.

1960 - The timing looks highly suspect with an apparent error of -30 mins.

1964 - There is a suspected timing error between 26 Mar and 1 Apr.

1972 - Some timing problems, including 1-11 Jan, 1 Nov and 10 Nov.

1980 - Timing problems remain up to 12 August, data is suspect.

Gaps in the Data Record

The following gaps occur in the data set.

Quality Assessment

All data have been compared with the current Harmonic Constants library, and residuals checked. Records have been visually inspected for spikes, datum shifts and timing errors.

Missing and suspect data have been reported on the following day numbers.

Completeness index is presented for the primary channel only. Where there is more than one channel, ASLVBG02 is the primary channel.

Aberdeen (Scotland) Datum Information 1980-

Benchmark Relationships

• TGZ = Chart Datum = 2.25m below ODN
• TGZ = Chart Datum = 6.318m below TGBM
• TGZ = Chart Datum = 6.326m below Aux 1
• TGZ = Chart Datum = 7.155m below Aux 2

Glossary

• TGZ = Tide Gauge Zero
• TGBM = Tide Gauge Benchmark
• AUX = Auxiliary Benchmark
• ODN = Ordnance Datum Newlyn
• CD = Chart Datum

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: Aberdeen

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

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