Mombasa (Kenya) Site History
History Summary
| Station | Mombasa |
|---|---|
| Country | Kenya |
| Latitude | 04° 04.2' S |
| Longitude | 039° 39.4' E |
| GLOSS No | 008 |
| Time Reference | GMT (hours 00-23) |
| Contributor | UH Sea Level Center in collaboration with Kenya Marine and Fisheries Institute |
| Instrument Type | Leupold and Stevens, model A-71, float gauge |
| Site of Gauge | The gauge is situated between Telegraph Point and the yacht club at Ras Liwotoni. |
| Observational periods | 1986 - present |
Reference Level
All heights have been referred to the station tide gauge zero which is linked to fixed benchmarks.
Tide gauge benchmark (TGBM) description
| Benchmark | Elevation | Description |
|---|---|---|
| BM@ | 3.8m | This is a bolt fixed on the tide staff. |
| BM1 | 5.683m | TGZ is below BM1 - June 1989. |
| BM2 | 5.850m | TGZ is below BM2 - June 1989. |
| BM3 | 13.883m | TGZ is below BM3 - April 1987. |
| BM N-3 | 6.226m | TGZ is below TGZ - June 1989. |
Datum Levels
| Tide gauge zero (TGZ) | 0.942 m (Admiralty Chart Datum) |
|---|---|
| TGZ | 0.912 m (East African Railways Datum) |
| TGZ | 2.790 m (from 1989) (Survey of Kenya Datum) |
| TGZ | 3.800m below BM@ |
Quality Assessment by the UH Sea Level Center
Comment
The daily and monthly means do not reveal any reference level shifts and agree well with an adjacent station, Zanzibar, except for about a 10 day period of 9-20 February 1990 when the daily values show a suspicious drop. Another suspicious rise occurs on 14-17 June 1990. These features are not identifiable in the tide staff observations.
The timing of the hourly data is uncertain to about 4 minutes for most of the record with periods of less accuracy as noted below under questionable fluctuations. The timing is more accurate beginning in 1992.
| Year | CI (%) | Missing Data | Replaced Gaps or Bad Data | Questionable Fluctuations |
|---|---|---|---|---|
| 1986 | 51 | 254-258,304-308,333-335,355-357 | (13)216-(00)217 (15)217-(23)217 (19)219-(06)220 (23)222-(08)223 (02)320-(19)320 (01)324-(19)324 | 175,214-215,231-233,260-264,282,317-319,358-360 |
| 1987 | 78 | 37-40,130-132,147-159,215-222,310-365 | (13)048-(21)048 (17)050-(03)051 (20)052-(05)053 (12)136-(22)136 (00)137-(10)137 (18)160-(05)161 (14)161-(23)161 (04)171-(23)171 | 59-60,67,73-74,80-84,88-89,91,93,106,134,142-147,168-169,173,177-178,194-195,214,222,224,227-228,275-278,281 |
| 1988 | 93 | 1-59,94-96,151-154,232-243,245-252,332-335 | none | 79-81,83-84,93-94,100-103,108-110,129-130,139-142,150-151,245,268-270,319,337,344-345 |
| 1989 | 98 | 104-107,122-124,242-244 | none | 6-7,27,39,66-67,69,78-79,87,97-99,126,137-139,152-162,164,166,169-178,183-184,186-191,200-201,213- 214,216-218,228-232,241,286-291,341-342 |
| 1990 | 75 | 17-22,53-59,145-150,161-164,199-218,226-236, 255-263,290-292,305-309 | none | 10,23,29,40-41,61-62,66,69-73,84,86-91,94-95,97,100-106,117-120,125-126,130-131,138-139,150-159,164-181,187-190,192-198,237-239,247-152,275-280,288-290,300-302,304,309-310,314-315,318,322-323,327-328,333 |
| 1991 | 41 | 1-216 | none | 221-226,238-241,253- 256 |
| 1992 | 99 | 11-13 | none | none |
| 1993 | 99 | 151-153,303-304 | none | none |
| 1994 | 63 | 1-46,93-106,118-130,134-138,303-365 | (00)070-(13)070 | none |
| 1995 | 50 | 1-183 | none | none |
| 1996 | 100 | none | none | none |
| 1997 | 45 | 015-066,099-251 | none | none |
| 1998 | 99 | 309-310,325-327 | none | none |
