QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 01 Nov 2019 Station : Port Elizabeth Latitude: 33 57.6S Country : South Africa Longitude: 025 37.8E JASL # : 184A Time Meridian: 030E (GMT + 2 hr) GLOSS # : 076 Originator #: PE NODC #: 33023501 Contributor : South Africa Navy Hydrographic Office (SANHO) Private Bag X1 Tokai 7966 South Africa Originator : same Original Data: analog (LEA,OTT); digital (SRD,radar) Instrmnt Type: 1) LEA float-type gauge 1954 - 1982. 2) OTT float-type 1968 - 1997. 3) SRD acoustic gauge 1996-6/2005 4) OTT Kalesto Radar gauge, 6/2005- Digitzd Intvl: hourly (LEA,OTT); 3-minute (SRD); 1-minute (radar) Present Data : Hourly, daily, and monthly values obtained by: Hourly : manually filtered raw data (LEA,OTT); average 9 min either side of hour (SRD,radar) 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 : 01 Mar 1973 - 31 Dec 2018 Gaps > 1 mon : 31 May 1973 - 15 Jun 1978;04 Jun 1988 - 04 Jul 1988 03 Apr 1990 - 13 Jul 1990;31 Aug 1990 - 28 Nov 1990 27 May 1991 - 23 Aug 1991;26 Feb 1992 - 08 Apr 1992 16 Oct 1993 - 02 Dec 1993;05 Jan 1994 - 27 Feb 1994 30 Mar 1994 - 06 May 1994;15 Jul 1995 - 03 Oct 1995 30 Oct 1995 - 08 Dec 1995;31 Dec 1995 - 27 Jun 1997 18 Sep 1997 - 23 Oct 1997;31 Dec 1998 - 01 Jan 2000 28 Apr 2011 - 09 Jun 2011;07 Mar 2013 - 15 May 2013 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1973-2018 Refernce Levl: All tidal heights are given above Chart Datum, which is the datum to which all soundings on the largest scale navigational chart of the area have been reduced. Chart datum is now Lowest Astronomical Tide (LAT) in all ports of the Republic of South Africa and Namibia. The relationship between LAT and Lands Leveling Datum (LLD), referred to as Mean Sea Level (MSL) by land surveyors, is given below. GPS = 4.373m below MSL New GPS = 4.356m below MSL BM PE1 = 4.285m below MSL 2003-2008 TGZ 5.121 m below BM PE1 TGZ was changed on 01 Jan 2003 onward as Mean Sea Level, which is the Land Leveling Datum. Comment : SANHO is the owner and copyright holder of the sea level data. Anyone downloading the information is to contact SANHO to request permission to use or reproduce the data. Permission can be requested via email to hydrosan@iafrica.com. The location is inside the tide gauge hut on the side of the Ro-Ro berth at the base of the Charl Malan Quay. Comparison with altimeter data show a stable reference level. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1973 21 68-71,95-99,100-109, (22)090-(05)091 62-65,79-81,92-96, 117-120,151-365 (22)099-(05)100 112-122,132-135 (22)123-(11)124 (23)128-(06)129 (22)141-(21)142 (19)149-(11)150 1974 0 1-365 none none 1975 0 1-365 none none 1976 0 1-366 none none 1977 0 1-365 none none 1978 48 1-166,168-172,211- (11)184-(05)185 211 212,219-226,231-234, (13)193-(08)194 250-254,298-303,330- 334 1979 84 25-26,82-87,97-107, (22)056-(10)057 none 115-119,146-149,232- (09)365-(21)365 234,278-305,308-311 1980 98 82-84,86-88,219-221, (04)116-(12)116 54-56,195-197 226-228,254-255 (23)143-(14)144 (22)174-(12)175 1981 89 86-100,153-163,209- (14)188-(06)189 none 217,244-245,271-273, (22)323-(06)324 304-308 1982 97 93-103,352-354 none none 1983 97 67-70,80-82,112-115, (22)237-(06)238 none 155-158,260-262 1984 97 51-53,182-184,203- (10)002-(09)003 none 205,318-319,360-366 (02)104-(13)104 1985 100 none none 145 1986 97 12-14,144-146,252- (12)041-(09)042 112-113,365 255,365 (16)117-(14)118 (22)335-(12)336 1987 90 1-2,57-61,68-77,135- (11)209-(06)210 156 141,151-153,180-182, (00)294-(12)294 262-266,321-330 1988 86 46-48,76-78,156-186, (20)074-(13)075 43-46 214-216,268-272,296- (17)290-(09)291 298,300-301,356-366 1989 83 39-41,70-73,74-80, (10)045-(06)046 none 101-114,141-153,243- (20)073-(06)074 250,278-282,308-310, (19)172-(12)173 336-347,352-355 (09)201-(08)202 (12)212-(23)212 (01)213-(08)213 (13)228-(06)229 (04)241-(21)241 (22)285-(21)286 (13)317-(06)318 (15)319-(06)320 1990 40 26-29,56-57,80-82, (11)039-(21)039 243 93-194,203-209,211- 212,230-232,236-332, 356-365 1991 70 1-2,29-36,41-43,90- (22)002-(21)003 46,58-59,64,104 100,147-235 (22)262-(12)263 (13)315-(12)316 (23)343-(06)344 1992 79 2-30,58-90,91-99, (22)115-(18)116 90,129-132,194-204 185-188,204-206,234- (21)117-(08)118 238 (18)128-(08)129 (18)130-(08)131 (21)146-(06)147 (14)154-(10)155 (14)175-(06)176 (18)193-(06)194 (18)199-(10)200 (06)201-(14)201 (08)234-(20)234 (16)264-(06)265 (00)294-(08)294 (03)321-(13)321 1993 84 3-7,94-97,123-127, (05)010-(04)011 91,98-102,262-263, 259-261,289-336 (20)024-(03)025 364-365 (12)035-(04)036 (17)040-(07)041 (17)052-(04)053 (13)067-(04)068 (03)169-(17)169 (20)195-(16)196 (20)250-(06)251 1994 53 5-58,61-67,89-126, (20)087-(05)088 1-5,149,233-237, 168-185,211-242,268- (03)151-(21)151 241-242 271,298-309,326-340, (23)151-(09)152 364-365 (00)204-(20)204 (02)211-(21)211 (22)349-(21)350 1995 66 1-3,162-165,170-171, (09)030-(08)031 87-88 196-276,303-342 1996 0 1-366 none none 1997 42 1-178,261-296,365 none none 1998 97 73-76,265-274 (16)066-(05)067 none (16)245-(15)246 1999 0 1-365 none none 2000 97 296-306 none none 2001 99 321-325 none none 2002 99 273-275 (23)284-(15)285 none (22)365-(16)001 2003 97 210-220,232-233 (13)205-(21)205 none (07)234-(15)234 (22)365-(10)001 2004 95 13-26,355-357,361- (04)221-(21)221 none 364,366 2005 96 1-3,151-160,297-298 (19)142-(03)143 none 2006 100 none none 192-365 2007 97 163-166,239-241, (03)137-(14)137 1-137 323-330 (22)255-(21)256 (22)257-(21)258 2008 99 315-318 none none 2009 98 140-141,174-178, none 61-365 300-301,346-347 2010 99 83-85 (07)266-(22)266 none 2011 88 60-62,118-160 (22)115-(21)116 none 2012 100 none none none 2013 80 44-45,55-56,66-135 (07)063-(16)063 none 2014 98 360-365 none none 2015 99 1,104-105,314-316 (22)257-(21)258 none (23)258-(21)259 2016 100 none (03)167-(12)167 none 2017 100 none none none 2018 93 4-26,279-281,285- (13)037-(21)037 none 288,365 (22)058-(21)059 (13)197-(20)197 (14)215-(08)216 (22)227-(10)228 (14)272-(08)273 (22)277-(21)278