Durban (South Africa) Site History

History Summary

Station Durban
Country South Africa
GLOSS No 013
Latitude 029° 52.0' S
Longitude 031° 03.0' E
Contributor 1970-1987: TOGA Sea Level Center
1988-1994: South African Hydrographic Office
Instrument Type Float and stilling well gauge
Location In the tide gauge hut at the Tug Jetty (Small Craft Harbour) at the point
Observational periods 1954-1958, 1960-present

Tide Gauge Benchmark (TGBM) Description

Trig survey BM 4212 is at the east end of Salisbury Island. UTM Grid Reference 36 JUB 109930.

Benchmark relationships

All heights have been referred to the station tide staff zero which is linked to fixed benchmarks. The original data were adjusted with leveling information provided by the contributors to the 1987 data as follows:

Period ((hour)day/month/year) Value Added to
Original (mm)
*(00)30/09/70-(20)18/06/73 -100
(21)18/06/73-(23)13/05/75 -250
(00)14/05/75-(12)13/08/80 100
*(13)13/08/80-(23)30/03/81 -150
(00)31/03/81-(06)24/04/84 150
(07)24/04/84-(23)28/11/84 -320
*(00)29/11/84-(00)15/07/85 -120

*Correction of shift in reference level deduced from the plot of hourly residuals, daily and monthly means, and differences with the corrected monthly means of the Permanent Service for Mean Sea Level.

There is a datum shift of -230mm after the 31st December 1987. All post 1987 data were received from the South African Hydrographic Office and reference to South Africa Chart Datum. Therefore there is a 230mm difference between these data and those previously adjusted by the TOGA Sea Level Center to the 1987 data.

Quality Assessment

Comment

The timing of the gauge appears to be off by a fraction of an hour in some instances.

Following possible datum shifts noted:

Note

Timing shifted by +2 hours 1997 142-174

Year CI(%) QI(%) Missing Data Replaced Gaps or Bad Data Questionable Fluctuations
1970 25 24 none none See comment above
1971 100 86 none (22)232-(21)233 (22)236-(21)237 See comment above
1972 100 84 none (22)072-(21)073 See comment above
1973 98 84 141-149 (22)033-(21)034 (22)217-(21)218 (22)223-(21)224 (22)229-(21)230 (22)234-(21)235 (22)239-(21)240 (22)246-(21)247 (22)250-(21)251 (22)256-(21)257 (22)262-(21)263 (23)281-(05)282 (23)282-(06)283 (22)288-(21)289 (22)324-(21)325 See comment above
1974 73 68 42-127,238-246,259-262 (22)154-(21)155 See comment above
1975 85 78 104-133 none See comment above
1976 86 72 271-278,286-292,309-320,327-335 none See comment above
1977 93 92 136-157 none See comment above
1978 100 95 none none See comment above
1979 91 82 148-155,162-164,225-248 none See comment above
1980 100 98 none (12)196-(07)197 See comment above
1981 50 48 89-138,194-327 (16)073-(03)074 (16)074-(03)075 See comment above
1982 100 97 none (14)221-(09)222 See comment above
1983 98 80 172-175,328-332 none See comment above
1984 87 70 47-51,63-79,161-163,310-335 (11)018-(18)018 (23)018-(08)019 (10)019-(19)019 (22)019-(20)020 (01)021-(08)021 (06)038-(00)039 (06)039-(05)040 See comment above
1985   46 34 (09)201-(16)201 (10)202-(16)202 See comment above
1986 78 62 99-105,118-119,168-184,252-259,270-287,295-301,320-322,336-358 (06)117-(22)117 (04)323-(21)323 (05)326-(18)326 (05)327-(17)327 See comment above
1987 83 66 66-68,90-105,160-167,269-279,321-329,349-363 (06)020-(13)020 (07)268-(09)268 See comment above
1988 30 25 22,23,24,25,42-48,59-61,71-82,98-137,150,151-153,159-187,249-300,355-366 none 64-69,92-98,207-208,215-217,241-245
1989 85 85 25-26,72-73,128-132,170-192,286-298,351-363 none See comment above
1990 50 45 43-46,47,48,49,50-60,67-199,226-260 none 1-3,9-18,207-208,337-339,350-351,364-365
1991 78 65 61-62,62-63,64-65,67-77,85-87,105-116,167-211,221-222,223-224,287-294,299,325-329 none 1-7,42-51,56-61,77-85,87-105
1992 80 76 50-51,104-153,167-174,181-184,198-202,244,251,292-293,296-300 none 9-13,49-50,160-167,295-296,302
1993 87   66-68,133,134-152,169-170,170-171,171-172,172-173,184-187,187-188,194,201-207,211-222,235,272,302 none See comment above
1994 58   7,31,84-98,122-172,202-245,251-256,259-263,272-276,280-286,290-298,311-319,357-365 none See comment above
1995 76   26-30,90-91,125-129,132-142,156-158,162-198,244-254,282-290,317-321,365 none 15-19,91-93,122-125,160-162
1996 85   14-16,24-26,40-43,92-95,158-172,277-281,285-288,323-326,346-352,354-366 none 62-64,90-91,150,152-158,169-170,212-213,266
1997 61   1-142   See note above
2000 75 1-44,222-223,318-366 none   See comment above