QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 16 Apr 2019 Station : Mombasa Latitude: 04 04.2S Country : Kenya Longitude: 039 39.4E JASL # : 101A Time Meridian: 045E (GMT + 3 hr) GLOSS # : 008 TOGA #: I005 NODC #: 30034901 Contributor : UH Sea Level Center 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Originator : UH Sea Level Center in collaboration with Kenya Marine and Fisheries Institute P. O. Box 81651 Mombasa, Kenya Original Data: analog (LS); digital (ENO,RAD) Instrmnt Type: 1) 6/1986-10/1994, Leupold and Stevens, model A-71, float gauge (LS) 2) 10/1994-present, Handar Encoder 436B with datalogger (ENO) 3) 2006- radar (RAD) gauge (Vega Vegapuls 62) primary gauge 4) 2006- pressure transducer (PRS) backup Primary channel used in JASL set: 1986-1994: (LS) 1995-2005: (ENO) 2006- : (RAD) *short gaps in primary channel filled with other channels as available; see UHSLC for specific dates Digitzd Intvl: 1 hour spot (LS), 15 min (ENO), 3 min (RAD), 2 min (PRS) Present Data : Hourly, daily, and monthly values obtained by: Hourly : The original digitizing interval was hourly Daily : 119-point convolution filter (Bloomfield, 1976) centered on noon applied to the hourly data with respective periods of the 95, 50, and 5% amplitude points at 124.0, 60.2, and 40.2 hours Monthly: Simple average of all daily values; calculated if 7 or fewer days are missing Span of data : 17 Jun 1986 - 31 Dec 2018 Gaps > 1 mon : 06 Nov 1987 - 29 Feb 1988;01 Dec 1990 - 04 Aug 1991 01 Jan 1994 - 15 Feb 1994;30 Oct 1994 - 02 Jul 1995 15 Jan 1997 - 05 Mar 1997;10 Apr 1997 - 08 Sep 1997 01 Nov 2000 - 16 Aug 2001;27 Dec 2003 - 03 Feb 2004 17 Feb 2004 - 06 Aug 2006;22 Jul 2010 - 10 Nov 2011 01 Feb 2013 - 12 Mar 2013 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : No Distribution : 1986-2018 Refernce Levl: Heights are referred to the station tide staff zero, which is linked to land-based benchmarks. This reference zero is unique to this station and is not an official datum (chart, national, etc.) and is not relative to local tidal parameters, such as mean lower low water. See the Originators for benchmark descriptions, maps, and the geodetic levelling history. Reference level is questionable for Sept-Dec 1997. Lamu staff used to adjust the Mombasa record. 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 Feb 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 accurracy as noted below under questionable fluctuations. The timing is more accurate beginning in 1992. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1986 51 254-258,304-308, (13)216-(00)217 175,214-215,231-233, 333-335,355-357 (15)217-(23)217 260-264,282,317-319, (19)219-(06)220 358-360 (23)222-(08)223 (02)320-(19)320 (01)324-(19)324 1987 78 37-40,130-132, (13)048-(21)048 59-60,67,73-74,80- 147-159,215-222, (17)050-(03)051 84,88-89,91,93,106, 310-365 (20)052-(05)053 134,142-147,168-169, (12)136-(22)136 173,177-178,194-195, (00)137-(10)137 214,222,224,227-228, (18)160-(05)161 275-278,281 (14)161-(23)161 (04)171-(23)171 1988 93 1-59,94-96, none 79-81,83-84,93-94, 151-154,232-243, 100-103,108-110,129- 245-252,332-335 130,139-142,150-151, 245,268-270,319,337, 344-345 1989 98 104-107,122-124, none 6-7,27,39,66-67,69, 242-244 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, none 10,23,29,40-41,61- 145-150,161-164, 62,66,69-73,84,86- 199-218,226-236, 91,94-95,97,100-106, 255-263,290-292, 117-120,125-126,130- 305-309 131,138-139,150-159, 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, (00)070-(13)070 none 134-138,303-365 1995 50 1-183 none none 1996 100 none none none 1997 45 15-64,65-66,100-251 none none 1998 99 309-310,326-327 none none 1999 100 none none none 2000 81 1-2,34-35,61-62,97- none none 98,125-126,157-158, 183-184,217-218,249- 250,278-279,306-366 2001 38 1-228 none none 2002 100 none none none 2003 98 36-37,337-338,361- none none 365 2004 3 1-34,36-37,42-43, none none 48-366 2005 0 1-365 none none 2006 33 1-218,315-342 none none 2007 100 none none none 2008 100 none none none 2009 100 none (06)066-(13)066 none (07)123-(00)124 2010 52 15-16,159-161,170- (12)089-(04)090 none 172,175-177,181-184, (23)104-(06)105 186-188,198-200,201- (22)105-(08)106 365 (23)116-(06)117 (19)117-(04)118 (21)119-(04)120 (18)121-(04)122 (21)122-(04)123 (21)125-(11)126 (16)126-(06)127 (17)127-(04)128 (21)128-(05)129 (16)129-(04)130 (22)131-(05)132 (22)133-(05)134 (21)134-(04)135 (20)135-(04)136 (23)141-(07)142 (17)142-(04)143 (21)143-(06)144 (18)144-(04)145 (19)146-(05)147 (19)147-(04)148 (21)151-(04)152 (20)155-(04)156 (18)156-(04)157 (16)157-(04)158 (17)158-(04)159 (14)161-(07)162 (15)162-(05)163 (15)163-(05)164 (15)164-(05)165 (15)165-(05)166 (14)166-(06)167 (14)167-(07)168 (14)168-(07)169 (12)169-(08)170 (13)172-(08)173 (13)173-(06)174 (08)174-(05)175 (14)177-(06)178 (14)178-(06)179 (14)179-(08)180 (14)180-(10)181 (14)184-(06)185 (14)185-(06)186 (11)188-(06)189 (14)189-(07)190 (14)190-(07)191 (14)191-(06)192 (13)192-(07)193 (11)193-(06)194 (14)194-(06)195 (14)195-(07)196 (14)196-(08)197 (14)197-(06)198 (14)200-(07)201 2011 14 1-314 none none 2012 96 30-32,217-219,283- (12)262-(19)262 none 287,294-301,320-321, (02)263-(09)263 329-330 (17)264-(02)265 (06)265-(15)265 (04)272-(11)272 (16)272-(23)272 (23)273-(06)274 (09)277-(01)278 (04)278-(22)278 (11)279-(20)279 (00)280-(12)280 (01)281-(16)281 (23)281-(08)282 (07)287-(18)287 (01)288-(11)288 (14)288-(02)289 (04)289-(12)289 (14)289-(00)290 (06)290-(21)290 (03)291-(13)291 (04)292-(21)292 (05)293-(21)293 (03)296-(21)296 (05)298-(02)299 (05)302-(19)302 (03)303-(17)303 (01)304-(21)304 (02)305-(00)306 (10)313-(01)314 (04)314-(11)314 (14)315-(22)315 (00)320-(13)320 (19)321-(07)322 (13)322-(21)322 (02)323-(19)323 (02)324-(10)324 (13)324-(23)324 (22)325-(08)326 (11)326-(09)327 (18)328-(12)329 (07)331-(17)331 (02)333-(13)333 (23)333-(16)334 (18)334-(12)335 (21)335-(13)336 (16)336-(23)336 (04)337-(20)337 (14)338-(03)339 (07)343-(14)343 (19)343-(02)344 (07)348-(18)348 (03)349-(15)349 (17)349-(04)350 (06)350-(14)350 (17)350-(13)351 (08)352-(15)352 (17)354-(00)355 (19)357-(08)358 (20)358-(03)359 (16)363-(00)364 (03)364-(11)364 (17)364-(00)365 (04)366-(15)366 (05)001-(19)001 2013 89 30-32,32-71 (05)002-(20)002 none (03)003-(13)003 (09)006-(16)006 (12)007-(21)007 (23)008-(06)009 (16)016-(00)017 (12)023-(19)023 (10)024-(17)024 (09)025-(17)025 (10)026-(18)026 (10)027-(17)027 (13)174-(23)174 2014 100 none none none 2015 100 none none none 2016 100 none none none 2017 100 none none none 2018 99 255-256 none none