QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 22 Sep 2003 Station : Tarawa-C,Betio Latitude: 01 21.7N Country : Republic of Kiribati Longitude: 172 55.8E JASL # : 002C Time Meridian: 180E (GMT + 12 hr) GLOSS # : 113 TOGA #: P044 NODC #: 10171201 Contributor : UH Sea Level Center 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 --for the 1994 data The National Tidal Facility (NTF) Flinders University of South Australia GPO Box 2100 Adelaide, 5001, South Australia AUSTRALIA Originator : same Original Data: digital Instrmnt Type: 1) Leupold & Stevens Analog-to-Digital Recorder (ADR), 1988-11/1997 2) Handar Encoder, model 436A (ENC), 01/1988- 3) Handar Encoder, model 436B (ENB), 01/1988- 4) Aquatrak acoustic gauge (NTF) Primary gauge: ADR: 1988-90, ENC: 1991-1993, NTF: 1994, ENC: 1995-1997 Digitzd Intvl: 15 minutes (ADR and ENB), 4 or 10 (ENC), 6 (NTF) (average of 181 one minute samples) Present Data : Hourly, daily, and monthly values obtained by: Hourly : 3-point Hanning filter centered on the hour (UH); Cosine-Lanczos filter with cutoff of 120 min. (NTF) 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 : 20 Jan 1988 - 31 Dec 1997 Gaps > 1 mon : none Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : No Operational : No Sat. Trans. : No Distribution : 1988-1997 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. The UH data had problems in 1994 thus data from NTF were utilized. The 1994 NTF data were tied to the UH series by adding -22 mm. The series 002A, 002B, 002C, and 002D are separate because the location is different. Comment : The daily and monthly means reveal no apparent changes in the reference level and agree well with Nauru and Kanton. SPECIAL NOTE FOR USE OF NTF DATA: Supply of sea level data subject to the following conditions: i) When any data supplied by the National Tidal Facility is used in any publication or report, the origin of such data shall be acknowledged in that publication or report in the following approved form:-- "Tidal {predictions) for {port} {are} supplied {constants} {station} {is} {material} {...} by the National Tidal Facility, The Flinders University of South Australia, Copyright reserved." ii) All material is supplied in good faith and is believed to be correct. It is supplied on the condition that no warranty is given in relation thereto, that no responsibility or liability for errors or omissions is, or will be, accepted and that the recipient will hold the Flinders Univer- sity of South Australia and the National Tidal Facility free from all such responsibility or liability and from all loss or damage incurred as a consequence of any error or omission. iii) The acceptance of material and computations from the National Tidal Facility of the Flinders University of South Australia will be deemed to include acceptance of the conditions of supply. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1988 95 none none 212-214,238-242, 269-271 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 99 363-365 none none 1995 99 1 none none 1996 100 none none none 1997 100 none none none