QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 12 Aug 2013 Station : French Frigate Shoals-A Latitude: 23 52.1N Country : USA Longitude: 166 17.3W JASL # : 014A Time Meridian: 165W (GMT - 11 hr) GLOSS # : 107 Originator #: 014 NODC #: 72163601 Contributor : UH Sea Level Center 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Originator : Dept. of Oceanography University of Hawaii 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Original Data: digital Instrmnt Type: 1) 7/1974-10/1996, Fischer and Porter Analog-to-Digital Recorder (ADR) 2) 12/1987-04/2007, Bristol Bubbler (BUB) 3) 10/1996-04/2007, Handar Encoder 436A on datalogger (ENO) Primary channel used in JASL set: ADR:7/1974-10/1996, ENO:10/1996-11/2003 BUB:12/2003-01/2004 ENO:02/2004-04/2007 *short gaps in primary channel filled with other channels as available; see UHSLC for specific dates Digitzd Intvl: 15 min (ENO, BUB) Present Data : Hourly, daily, and monthly values obtained by: Hourly : (pre-1987) Nine-point triangular filter centered on the hour with respective periods of the 95, 50, and 5% amplitude point of the filter response at 623.6, 177.0, and 103.7 minutes;(1987+) 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 : 03 Jul 1974 - 06 Mar 2007 Gaps > 1 mon : 08 May 1986 - 01 Aug 1986;01 Feb 1987 - 31 Mar 1987 04 May 2004 - 29 Jun 2004;01 Aug 2004 - 10 Sep 2004 14 Jul 2006 - 09 Jan 2007 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1974-2007 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. This series 014A is separate from 014B because a reference level shift occurred during the gap in Mar-May 2007, and after the gap, the reference zero of 014B could not be resolved to 014A. Comment : The data from July 1974 to 16 August 1975 are from a standard float/well gauge (analog). The daily and monthly means reveal no obvious shifts or trends. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1974 50 none none none 1975 98 227-228,254-259 none none 1976 95 34-36,59-61, none none 115-116,199-200, 316-322 1977 90 220-224,306-335 none none 1978 99 322-324 none none 1979 98 21-23,299-300 none none 332-333 1980 98 56-61,160-162 none none 1981 99 167-169,259-260 none none 1982 100 none none none 1983 93 78-88,335-345, none none 356-358 1984 99 110-112 none none 1985 100 none none none 1986 71 70-79,128-213, none none 317-321,352-356 1987 83 32-90,204-206 none none 1988 100 none none none 1989 100 none none none 1990 100 none none none 1991 100 none none none 1992 100 none none none 1993 100 none none none 1994 99 305-306 none none 1995 100 none none none 1996 100 none none none 1997 100 none none none 1998 100 none none none 1999 100 none none none 2000 97 105-117,176-177 none none 2001 100 none none none 2002 100 none none none 2003 100 none none none 2004 62 107-122,125-181,214- (11)330-(18)330 none 254,336-363 (11)331-(18)331 (11)332-(19)332 (11)333-(19)333 (11)334-(20)334 (12)335-(21)335 2005 99 233-236 (12)164-(19)164 none 2006 50 176-180,182-183,185- (10)171-(18)171 none 190,192-193 (06)172-(20)172 (06)173-(22)173 (06)174-(21)174 (04)175-(19)175 (03)181-(21)181 (03)184-(21)184 (03)191-(20)191 (02)193-(20)193 (23)193-(21)194 2007 16 1-13,29-32,34-47,51- (11)014-(19)014 none 52,54-58 (03)047-(19)047 (10)063-(18)063 (08)064-(19)064