QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 07 Nov 2019 Station : Gan Latitude: 00 41.2S Country : Rep. of Maldives Longitude: 073 09.1E JASL # : 109A Time Meridian: 075E (GMT + 5 hr) GLOSS # : 027 TOGA #: I051 NODC #: 30070301 Contributor : UH Sea Level Center 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Originator : UH Sea Level Center in collaboration with Meteorology Station Addu Development Authority Gan, Republic of Maldives Original Data: analog (L&S); digital (F&P,ENC,ENB) Instrmnt Type: 1. (03/1987-10/1988) Leupold and Stevens Analog ANA 2. (10/1988-06/1990) Fischer and Porter Analog-to- Digital Recorder; 3. (1992-) Handar 436-A, Encoder (ENC); 4. (1992-4/2006) Handar 436-B (ENB) with datalogger (ENO) 5. 5/2006- pressure transducer (PRS) 6. 5/2006- radar (RAD) (Vega Vegapuls 62) Primary channel used in JASL set: 1987-1991: ANA 1992-1998: ENB 1999-2001: ENO 01/2002 - 08/2002: ENB 09/2002 - 04/2003: ENO 05/2003 - 09/2003: ENC 10/2003 - 04/2006: ENO 05/2006 - 11/2008: ENC 12/2008 - 2018 : RAD *short gaps in primary channel filled with other channels as available; see UHSLC for specific dates Digitzd Intvl: hourly (ANA); 15 minutes (FP,ENB,ENO); 4 min (ENC) 2 min (PRS); 3 min (RAD) Present Data : Hourly, daily, and monthly values obtained by: Hourly : Original data were spot hourly (L&S); A three- point Hanning filter centered on the hour 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 : 04 Mar 1987 - 31 Dec 2018 Gaps > 1 mon : 20 Jul - 08 Dec 1987; 01 Jan - 13 Apr 1988 02 Jun 1990 - 10 Jul 1991 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1987-2018 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. Comment : Differences in daily means with Cocos and Port Louis suggest that the reference level is stable. JASL NOV 2019 update replaces 2016- 05 Sep 2017. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1987 42 132-136,149-153, (03)120-(11)120 none 201-342 1988 60 1-104,115-135, (04)298-(12)298 none 176-179,213-233 1989 96 144-158 none none 1990 42 154-365 none none 1991 48 1-191 none none 1992 100 none none none 1993 100 none none none 1994 100 none (03)001-(15)001 none (02)019-(13)019 (02)121-(17)121 (06)206-(17)206 (13)259-(12)260 1995 100 none none none 1996 100 none none none 1997 100 none none none 1998 100 none none none 1999 99 228-231 none none 2000 100 none none none 2001 100 none none none 2002 98 255-264 none none 2003 100 none none none 2004 100 none none none 2005 100 none none none 2006 99 142-143 none none 2007 100 none none none 2008 100 none none none 2009 100 none (14)341-(02)342 none (12)342-(02)343 (13)343-(02)344 (14)344-(02)345 (15)345-(02)346 (12)346-(02)347 (14)347-(01)348 (16)348-(03)349 (15)349-(04)350 (13)350-(02)351 (13)351-(03)352 (16)352-(01)353 (17)353-(01)354 (15)354-(01)355 (15)355-(02)356 (15)356-(01)357 (16)357-(02)358 (14)358-(01)359 (16)359-(03)360 (13)360-(03)361 (14)361-(03)362 (13)362-(03)363 (12)363-(02)364 (14)364-(02)365 (12)365-(03)001 (14)001-(02)002 2010 99 47-49 (16)002-(02)003 none (16)003-(02)004 (15)004-(02)005 (15)005-(01)006 (15)006-(02)007 (15)007-(02)008 (15)008-(01)009 (15)009-(01)010 (14)010-(01)011 (15)011-(01)012 (14)012-(01)013 (15)013-(01)014 (15)014-(01)015 (15)015-(01)016 (15)016-(01)017 (15)017-(01)018 (16)018-(01)019 (16)019-(02)020 (16)020-(01)021 (16)021-(01)022 (15)022-(02)023 (11)023-(02)024 (15)024-(01)025 (15)025-(02)026 (16)026-(01)027 (14)027-(02)028 (15)028-(03)029 (15)029-(06)030 (13)030-(07)031 (10)031-(02)032 (14)032-(01)033 (15)033-(03)034 (15)034-(02)035 (14)035-(02)036 (15)036-(02)037 (15)037-(02)038 (15)038-(02)039 (15)039-(03)040 (14)040-(02)041 (13)041-(02)042 (14)042-(02)043 (13)043-(02)044 (14)044-(02)045 (13)045-(02)046 (13)046-(02)047 (11)049-(03)050 (13)050-(03)051 (13)051-(03)052 (14)052-(03)053 (13)053-(02)054 (13)054-(02)055 (13)055-(02)056 (13)056-(02)057 (13)057-(02)058 (13)058-(02)059 (12)089-(03)090 (00)335-(07)335 2011 100 none (11)181-(18)181 none 2012 100 none (12)256-(06)257 none 2013 100 none (13)174-(23)174 none 2014 100 none none none 2015 100 none none none 2016 100 none none none 2017 100 none none none 2018 99 27-29 (18)265-(12)266 none