Simonstown (South Africa) Site History

History Summary

Station name Simonstown (Cape Point)
Country South Africa
Latitude 34° 11.3' S
Longitude 018° 26.4' E
GLOSS No. 268
Time Reference  
Contributor (1958-1994) South African Hydrographic Office
Instrument type (1958-1995) Analog-to-Digital Recorder LEA float-type gauge
(1995-present) SRD Acoustic
Site of Gauge  
Observational periods 1958 - present

Reference Level

All data are referred to Tide Gauge Zero and are linked into historic fixed benchmarks.

Tide Gauge Benchmark (TGBM) Description

Trig survey BM 28 G. UTM Grid Reference 34 HBT 641144.

Benchmark Relationships

Quality Assessment

Comments

Residuals are extremely noisy. Large spikes > 20cm and chart reading errors have been flagged. Most questionable fluctuations are related to timing errors.

Possible datum shifts:

Years marked with * below refer to SRD acoustic gauge.

Year Completeness
Index (%)
Questionable Fluctuations (In day Nos.)
and Missing Data (Gaps > 6 hours)
1958 100 None
1959 100 70,81
1960 100 366
1961 100 1-3
1962 100 None
1963 100 236-237
1964 100 87,181-196
1965 99 None
    Gap from 1965/12/29 at 22.00 to 1965/12/31 at 21.00
1966 100 None
1967 100 139-142,160-162,177-183
1968 100 None
1969 100 None
1970 100 None
1971 100 6
1972 100 None
1973 100 None
1974 98 329-338
    Gap from 1974/08/17 at 22.00 to 1974/08/21 at 15.00
1975 100 319-326
1976 98 72-73,280-288,293-296
    Gap from 1976/01/04 at 07.00 to 1976/01/04 at 15.00
    Gap from 1976/03/13 at 22.00 to 1976/03/16 at 21.00
    Gap from 1976/10/10 at 00.00 to 1976/10/10 at 06.00
    Gap from 1976/12/26 at 20.00 to 1976/12/27 at 21.00
1977 100 None
1978 89 Large periods of intermittent timing errors throughout year.
    Gap from 1978/01/24 at 15.00 to 1978/01/31 at 21.00
    Gap from 1978/02/28 at 09.00 to 1978/03/07 at 08.00
    Gap from 1978/03/31 at 22.00 to 1978/04/04 at 21.00
    Gap from 1978/04/11 at 08.00 to 1978/04/18 at 08.00
    Gap from 1978/05/14 at 22.00 to 1978/05/15 at 21.00
    Gap from 1978/05/16 at 10.00 to 1978/05/22 at 00.00
    Gap from 1978/08/18 at 14.00 to 1978/08/19 at 11.00
    Gap from 1978/08/19 at 15.00 to 1978/08/21 at 13.00
    Gap from 1978/08/25 at 21.00 to 1978/08/26 at 03.00
    Gap from 1978/08/28 at 07.00 to 1978/08/28 at 14.00
1979 83 2-17,201-205
    Gap from 1979/01/17 at 22.00 to 1979/01/19 at 21.00
    Gap from 1979/05/01 at 08.00 to 1979/06/18 at 21.00
    Gap from 1979/07/10 at 10.00 to 1979/07/17 at 08.00
    Gap from 1979/09/01 at 23.00 to 1979/09/04 at 08.00
    Gap from 1979/10/30 at 22.00 to 1979/10/31 at 21.00
1980 100 None
1981 100 169-185
1982 98 150-151
    Gap from 1982/12/03 at 09.00 to 1982/12/08 at 08.00
1983 82 None
    Gap from 1983/04/04 at 17.00 to 1983/04/19 at 10.00
    Gap from 1983/04/26 at 08.00 to 1983/05/10 at 07.00
    Gap from 1983/06/07 at 09.00 to 1983/07/05 at 08.00
    Gap from 1983/07/20 at 08.00 to 1983/07/21 at 13.00
    Gap from 1983/07/29 at 15.00 to 1983/08/05 at 11.00
1984 93 Intermittent timing errors evident particularly upto the end of July.
    Gap from 1984/03/19 at 09.00 to 1984/03/19 at 23.00
    Gap from 1984/03/31 at 09.00 to 1984/04/02 at 12.00
    Gap from 1984/04/10 at 08.00 to 1984/04/17 at 09.00
    Gap from 1984/05/15 at 22.00 to 1984/05/23 at 10.00
    Gap from 1984/07/31 at 10.00 to 1984/07/31 at 21.00
    Gap from 1984/10/14 at 06.00 to 1984/10/16 at 09.00
    Gap from 1984/10/18 at 10.00 to 1984/10/23 at 08.00
1985 85 None
    Gap from 1985/06/07 at 09.00 to 1985/07/30 at 10.00
1986 97 None
    Gap from 1986/02/26 at 07.00 to 1986/03/03 at 11.00
    Gap from 1986/05/12 at 10.00 to 1986/05/19 at 06.00
1987 82 323-330,336-339,363-365
    Gap from 1987/07/26 at 01.00 to 1987/07/27 at 06.00
    Gap from 1987/07/28 at 21.00 to 1987/08/05 at 13.00
    Gap from 1987/08/20 at 07.00 to 1987/08/24 at 10.00
    Gap from 1987/08/31 at 08.00 to 1987/09/18 at 07.00
    Gap from 1987/09/21 at 08.00 to 1987/09/25 at 13.00
    Gap from 1987/10/06 at 07.00 to 1987/10/12 at 05.00
    Gap from 1987/12/05 at 22.00 to 1987/12/14 at 09.00
    Gap from 1987/12/14 at 16.00 to 1987/12/29 at 07.00
1988 59 19-23,47-53,64-82,96-101,123-126
    Gap from 1988/01/13 at 16.00 to 1988/01/18 at 13.00
    Gap from 1988/01/23 at 09.00 to 1988/01/25 at 08.00
    Gap from 1988/02/01 at 05.00 to 1988/02/09 at 11.00
    Gap from 1988/02/22 at 08.00 to 1988/03/04 at 08.00
    Gap from 1988/03/22 at 15.00 to 1988/03/23 at 07.00
    Gap from 1988/03/25 at 07.00 to 1988/04/05 at 08.00
    Gap from 1988/04/13 at 14.00 to 1988/04/14 at 06.00
    Gap from 1988/04/20 at 09.00 to 1988/05/02 at 09.00
    Gap from 1988/06/14 at 11.00 to 1988/06/21 at 13.00
    Gap from 1988/07/04 at 08.00 to 1988/07/18 at 10.00
    Gap from 1988/08/16 at 13.00 to 1988/08/22 at 07.00
    Gap from 1988/09/03 at 22.00 to 1988/09/30 at 07.00
    Gap from 1988/10/01 at 01.00 to 1988/10/04 at 10.00
    Gap from 1988/10/11 at 07.00 to 1988/11/10 at 11.00
    Gap from 1988/11/28 at 09.00 to 1988/12/13 at 08.00
1989 61 Large periods of intermittent timing errors throughout year.
    Gap from 1989/03/31 at 12.00 to 1989/07/07 at 20.00
    Gap from 1989/07/07 at 22.00 to 1989/08/03 at 21.00
    Gap from 1989/08/03 at 23.00 to 1989/08/04 at 10.00
    Gap from 1989/08/09 at 09.00 to 1989/08/23 at 12.00
1990 92 1-12,347-351
    Gap from 1990/05/02 at 17.00 to 1990/05/03 at 02.00
    Gap from 1990/05/03 at 05.00 to 1990/05/03 at 13.00
    Gap from 1990/05/03 at 18.00 to 1990/05/04 at 02.00
    Gap from 1990/05/04 at 08.00 to 1990/05/07 at 14.00
    Gap from 1990/05/11 at 10.00 to 1990/05/12 at 05.00
    Gap from 1990/05/12 at 08.00 to 1990/05/13 at 05.00
    Gap from 1990/05/22 at 16.00 to 1990/05/23 at 09.00
    Gap from 1990/07/30 at 10.00 to 1990/08/06 at 10.00
    Gap from 1990/09/04 at 05.00 to 1990/09/06 at 11.00
    Gap from 1990/11/26 at 09.00 to 1990/12/04 at 10.00
1991 86 46-50,96-97,102-106,128-135,182-190,302-304
    Gap from 1991/01/01 at 16.00 to 1991/01/04 at 08.00
    Gap from 1991/02/25 at 10.00 to 1991/02/28 at 08.00
    Gap from 1991/03/19 at 08.00 to 1991/04/02 at 13.00
    Gap from 1991/06/10 at 08.00 to 1991/06/18 at 07.00
    Gap from 1991/06/21 at 22.00 to 1991/06/27 at 08.00
    Gap from 1991/07/09 at 08.00 to 1991/07/11 at 07.00
    Gap from 1991/12/10 at 09.00 to 1991/12/23 at 08.00
1992 87 1-6
    Gap from 1992/01/06 at 07.00 to 1992/01/21 at 10.00
    Gap from 1992/02/19 at 08.00 to 1992/03/03 at 14.00
    Gap from 1992/03/26 at 20.00 to 1992/03/30 at 10.00
    Gap from 1992/08/07 at 13.00 to 1992/08/11 at 06.00
    Gap from 1992/10/02 at 07.00 to 1992/10/12 at 09.00
    Gap from 1992/10/26 at 10.00 to 1992/10/30 at 07.00
1993 92 191,193,337,344-347
    Gap from 1993/08/11 at 13.00 to 1993/08/16 at 10.00
    Gap from 1993/08/30 at 08.00 to 1993/09/10 at 07.00
    Gap from 1993/10/15 at 09.00 to 1993/10/19 at 07.00
    Gap from 1993/11/16 at 10.00 to 1993/11/25 at 08.00
    Gap from 1993/12/09 at 13.00 to 1993/12/10 at 09.00
1994 57 188-195
    Gap from 1994/02/16 at 22.00 to 1994/02/17 at 07.00
    Gap from 1994/03/11 at 22.00 to 1994/03/16 at 21.00
    Gap from 1994/06/06 at 12.00 to 1994/06/06 at 18.00
    Gap from 1994/06/09 at 08.00 to 1994/07/01 at 06.00
    Gap from 1994/07/18 at 10.00 to 1994/07/22 at 09.00
    Gap from 1994/08/03 at 14.00 to 1994/11/03 at 09.00
    Gap from 1994/11/07 at 09.00 to 1994/12/02 at 08.00
    Gap from 1994/12/23 at 08.00 to 1994/12/31 at 21.00
1995 57 012-018,047-051,063,064,128-130,145-150,266-269,357
    Gap from 1995/01/27 at 14.00 to 1995/01/27 at 21.00
    Gap from 1995/02/03 at 20.00 to 1995/02/15 at 21.00
    Gap from 1995/02/22 at 00.00 to 1995/02/22 at 07.00
    Gap from 1995/03/05 at 22.00 to 1995/03/13 at 12.00
    Gap from 1995/03/24 at 09.00 to 1995/03/24 at 21.00
    Gap from 1995/03/30 at 14.00 to 1995/04/05 at 10.00
    Gap from 1995/04/06 at 22.00 to 1995/04/11 at 09.00
    Gap from 1995/04/14 at 14.00 to 1995/04/14 at 21.00
    Gap from 1995/04/15 at 14.00 to 1995/04/15 at 22.00
    Gap from 1995/04/28 at 22.00 to 1995/05/03 at 08.00
    Gap from 1995/05/10 at 22.00 to 1995/05/25 at 08.00
    Gap from 1995/06/20 at 11.00 to 1995/07/11 at 07.00
    Gap from 1995/07/14 at 07.00 to 1995/07/21 at 17.00
    Gap from 1995/07/25 at 22.00 to 1995/07/28 at 12.00
    Gap from 1995/08/01 at 13.00 to 1995/08/07 at 14.00
    Gap from 1995/08/10 at 10.00 to 1995/08/11 at 09.00
    Gap from 1995/09/08 at 10.00 to 1995/09/19 at 08.00
    Gap from 1995/09/26 at 10.00 to 1995/10/25 at 13.00
    Gap from 1995/10/31 at 13.00 to 1995/11/14 at 09.00
    Gap from 1995/12/03 at 08.00 to 1995/12/04 at 09.00
    Gap from 1995/12/07 at 07.00 to 1995/12/07 at 15.00
    Gap from 1995/12/12 at 22.00 to 1995/12/13 at 09.00
    Gap from 1995/12/18 at 18.00 to 1995/12/21 at 07.00
1995* 73 None
    Gap from 1995/01/16 at 05.00 to 1995/02/15 at 04.00
    Gap from 1995/02/17 at 17.00 to 1995/02/20 at 10.00
    Gap from 1995/02/21 at 05.00 to 1995/03/02 at 07.00
    Gap from 1995/03/08 at 20.00 to 1995/03/09 at 07.00
    Gap from 1995/03/27 at 14.00 to 1995/03/28 at 01.00
    Gap from 1995/04/24 at 02.00 to 1995/04/26 at 06.00
    Gap from 1995/06/06 at 01.00 to 1995/06/12 at 06.00
    Gap from 1995/07/03 at 01.00 to 1995/07/03 at 12.00
    Gap from 1995/07/17 at 19.00 to 1995/07/19 at 06.00
    Gap from 1995/10/01 at 13.00 to 1995/10/02 at 00.00
    Gap from 1995/10/29 at 07.00 to 1995/10/30 at 12.00
    Gap from 1995/11/21 at 07.00 to 1995/11/21 at 13.00
    Gap from 1995/11/29 at 08.00 to 1995/11/30 at 01.00
    Gap from 1995/12/01 at 02.00 to 1995/12/31 at 21.00
1996* 75 None
    Gap from 1996/02/26 at 14.00 to 1996/02/27 at 01.00
    Gap from 1996/03/25 at 08.00 to 1996/04/02 at 01.00
    Gap from 1996/04/09 at 20.00 to 1996/04/15 at 13.00
    Gap from 1996/04/29 at 02.00 to 1996/04/29 at 13.00
    Gap from 1996/07/22 at 08.00 to 1996/07/25 at 12.00
    Gap from 1996/08/01 at 13.00 to 1996/08/02 at 00.00
    Gap from 1996/08/23 at 07.00 to 1996/11/01 at 00.00
    Gap from 1996/12/30 at 07.00 to 1996/12/30 at 21.00
    Gap from 1996/12/31 at 01.00 to 1996/12/31 at 21.00