Gibraltar Site History

History Summary

Station name Gibraltar
Country United Kingdom
GLOSS No. 248
Contributor (1961-1996) Hydrographic Office,
Ministry of Defence,
Taunton, Somerset
Instrument type (1961-1996) Float and stilling well gauge
A replacement gauge started operating in Nov 1994
Site of Gauge The tide gauge is situated in Gibraltar harbour at the north end of the main wharf.
Observational periods 1961-1990,1993-2000

Reference Level

All heights have been referred to the station tide gauge zero which is linked to fixed bench marks

Benchmarks

Benchmark Description
TGBM Top of coping north of tide gauge hut.
BM '18'
(Auxilliary)
On SW face of main dockyard wall, North Jumper's Bastion.
(Grid reference TF 8835 0123)

Benchmark Relationships

Tide Gauge Zero (TGZ) set to Admiralty Chart Datum which is 3.20m below TGBM (1984 onwards).

Quality Assessment

Comment

The timing of the gauge appears to be off by a fraction of an hour in some instances. Most questionable fluctuations are related to timing errors.

Chart reading errors and spikes >10cm have been flagged.

Possible datum shift of -26cm on 1st January 1965.

Possible change of datum between August 1979 and December 1979, Jun 1990 and Mar 1993.

Year Completeness Index (%) Questionable Fluctuations (In day Nos.)
and Missing Data (Gaps > 6 hours)
1961 41 242,274,280
    Gap from 1961/08/11 at 12.00 to 1961/08/11 at 23.00
    Gap from 1961/09/01 at 00.00 to 1961/09/30 at 23.00
    Gap from 1961/10/01 at 08.00 to 1961/10/02 at 06.00
1962 100 76-77,84-85,104-106,145,329,282-312
1963 99 2,25-26,37-38,44,112,186,208-209,352,361-364
    Gap from 1963/01/02 at 06.00 to 1963/01/04 at 12.00
1964 100 3,63,231-232,362
1965 98 57-60,184
    Gap from 1965/01/23 at 12.00 to 1965/01/23 at 23.00
    Gap from 1965/05/14 at 12.00 to 1965/05/14 at 23.00
    Gap from 1965/07/25 at 12.00 to 1965/07/25 at 23.00
    Gap from 1965/10/04 at 12.00 to 1965/10/04 at 23.00
    Gap from 1965/12/16 at 19.00 to 1965/12/17 at 06.00
1966 99 None
    Gap from 1966/04/30 at 12.00 to 1966/04/30 at 23.00
    Gap from 1966/07/19 at 12.00 to 1966/07/22 at 23.00
1967 100 7,333-335,345
1968 100 None
1969 100 240-241,313
1970 100 144
1971 100 2-3
1972 99 292-294,330-331
    Gap from 1972/06/26 at 08.00 to 1972/06/27 at 10.00
1973 100 None
1974 62 None
    Gap from 1974/08/15 at 21.00 to 1974/08/16 at 06.00
    Gap from 1974/08/30 at 08.00 to 1974/09/03 at 06.00
    Gap from 1974/09/16 at 08.00 to 1974/09/21 at 06.00
1975 99 214-215,228-231,235-242
    Gap from 1975/01/18 at 08.00 to 1975/01/20 at 07.00
1976 99 80-81,91-92,108-110
    Gap from 1976/04/02 at 09.00 to 1976/04/03 at 06.00
    Gap from 1976/04/26 at 08.00 to 1976/04/30 at 06.00
1977 99 180-181
    Gap from 1977/05/08 at 15.00 to 1977/05/09 at 10.00
    Gap from 1977/10/12 at 12.00 to 1977/10/12 at 23.00
    Gap from 1977/10/13 at 14.00 to 1977/10/14 at 05.00
1978 99 None
    Gap from 1978/03/02 at 15.00 to 1978/03/03 at 06.00
    Gap from 1978/09/19 at 12.00 to 1978/09/19 at 23.00
    Gap from 1978/10/27 at 23.00 to 1978/10/30 at 06.00
1979 66 None
    Gap from 1979/04/01 at 00.00 to 1979/04/02 at 06.00
    Gap from 1979/05/08 at 07.00 to 1979/05/09 at 06.00
    Gap from 1979/05/12 at 08.00 to 1979/05/13 at 07.00
    Gap from 1979/05/25 at 12.00 to 1979/05/26 at 06.00
    Gap from 1979/05/31 at 21.00 to 1979/06/01 at 06.00
    Gap from 1979/08/12 at 12.00 to 1979/12/10 at 06.00
1980 99 None
    Gap from 1980/04/06 at 00.00 to 1980/04/07 at 08.00
    Gap from 1980/05/14 at 00.00 to 1980/05/14 at 07.00
    Gap from 1980/09/17 at 12.00 to 1980/09/17 at 23.00
1981 98 313-317
    Gap from 1981/01/29 at 12.00 to 1981/01/29 at 23.00
    Gap from 1981/03/09 at 12.00 to 1981/03/09 at 23.00
    Gap from 1981/03/15 at 00.00 to 1981/03/16 at 11.00
    Gap from 1981/08/19 at 12.00 to 1981/08/19 at 23.00
    Gap from 1981/10/04 at 00.00 to 1981/10/05 at 06.00
    Gap from 1981/10/26 at 16.00 to 1981/10/27 at 06.00
    Gap from 1981/12/19 at 12.00 to 1981/12/19 at 21.00
1982 99 38
    Gap from 1982/02/07 at 19.00 to 1982/02/08 at 06.00
    Gap from 1982/04/29 at 00.00 to 1982/04/29 at 06.00
1983 99 None
    Gap from 1983/03/14 at 19.00 to 1983/03/15 at 07.00
1984 99 None
    Gap from 1984/01/04 at 21.00 to 1984/01/05 at 07.00
1985 81 95-97,162-165, timing questionable from 252 onwards
    Gap from 1985/03/04 at 09.00 to 1985/03/14 at 14.00
    Gap from 1985/09/08 at 14.00 to 1985/09/09 at 07.00
    Gap from 1985/10/04 at 16.00 to 1985/10/05 at 08.00
    Gap from 1985/10/06 at 09.00 to 1985/10/07 at 07.00
    Gap from 1985/10/13 at 00.00 to 1985/10/13 at 16.00
    Gap from 1985/10/14 at 00.00 to 1985/10/14 at 06.00
    Gap from 1985/10/27 at 10.00 to 1985/10/28 at 06.00
    Gap from 1985/10/29 at 16.00 to 1985/10/30 at 06.00
    Gap from 1985/11/01 at 00.00 to 1985/11/01 at 08.00
    Gap from 1985/11/03 at 09.00 to 1985/11/04 at 06.00
    Gap from 1985/11/07 at 08.00 to 1985/11/09 at 06.00
    Gap from 1985/11/10 at 08.00 to 1985/11/11 at 06.00
    Gap from 1985/11/14 at 16.00 to 1985/11/15 at 08.00
    Gap from 1985/11/15 at 15.00 to 1985/11/15 at 23.00
1986 67 None
1987 32 264-266,306-313
    Gap from 1987/10/25 at 23.00 to 1987/10/26 at 06.00
    Gap from 1987/10/27 at 11.00 to 1987/10/30 at 06.00
1988 95 95-97
    Gap from 1988/01/02 at 08.00 to 1988/01/06 at 06.00
    Gap from 1988/02/26 at 09.00 to 1988/02/29 at 06.00
    Gap from 1988/03/07 at 14.00 to 1988/03/15 at 06.00
    Gap from 1988/03/31 at 23.00 to 1988/04/04 at 18.00
1989 98 None
    Gap from 1989/10/20 at 15.00 to 1989/10/23 at 06.00
    Gap from 1989/12/11 at 08.00 to 1989/12/16 at 09.00
1990 42 116
    Gap from 1990/01/29 at 00.00 to 1990/01/29 at 09.00
    Gap from 1990/04/07 at 13.00 to 1990/04/07 at 19.00
1993 68 114-115,296-334
1994 11 None
1995 100 See comment above
1996 100 None
1997 84 248,284-287
    Gap from 1997/11/06 at 00.00 to 1997/12/31 at 23.00
1998 39 Gap from 1998/01/01 at 00.00 to 1998/01/05 at 06.00
    Gap from 1998/05/27 at 08.00 to 1998/12/31 at 23.00
    Severe timing error throughout year. Data deemed u/s
1999 54 GAP GROM 1999/01/01 at 00.00 to 1999/04/05 at 09.00
    Gap from 1998/09/21 at 10.00 to 1999/12/31 at 23.00
    Severe timing error throughout year. Data deemed u/s
2000 5 Gap from 2000/01/01 at 00.00 to 2000/04/05 at 09.00
    Gap from 2000/05/01 at 00.00 to 2000/12/31 at 23.00
    Severe timing error throughout year. Data deemed u/s