Nauru Site History

Site

Station Nauru
Country Republic of Nauru
Latitude 00° 31.7' S
Longitude 166° 54.3' E
GLOSS No 114
Time Reference GMT (hours 00-23)
Contributor
upto 4/01/1995
UH Sea Level Center
1000 Pope Road. MSB 317
Honolulu,
Hawaii 96822
Contributor
4/01/1995 onward
The National Tidal Facility (NTF),
Flinders University of South Australia GPO box 2100
Adelaide, 5001,
South Australia
Instrument Type 1. (May 1974 - October 1985 )Fischer and Porter Analog-to-Digital Recorder (ADR)
2. (primary,Oct 1985-present) Leupold and Stevens Analog-to-Digital Recorder (ADR)
3. (backup,Feb 1984-present) Handar Encoder (ENC) (1993-1994 ENC primary)
4. NTF: Aquatrak acoustic gauge (SEAFRAME) (primary 4/Jan/1995 onward)
Site of Gauge  
Observational periods 1974 - 2001

Reference Level

All heights have been referred to the station tide staff zero which is linked to fixed bench marks. The NTF series was tied to the existing series by adding 219 mm.

Tide Gauge Benchmark (TGBM) Description

Benchmark Description
UH-1 The recessed triangle (steel pin is rusted away), has no stamp and is located two feet east of the tide well and one foot away from the edge of quay (established 01 May 1974).
UH-2B 0.5 inch hex head SS screw is set in epoxy with 'BM2B' written in the cement. It is located near crane warehouse wall below harbour masters office.
UH-3B 0.5 inch hex head bolt is set in epoxy with 'BM3B' written in the cement. It is located on the upper curb of Queen's Landing, 50 ft south of the habour masters house.
UH-6A 3/8 inch brass, located on left side of red door, it is the right hand pin of pair (UH-2B, UH-3B established August 1983, UH-6A - October 1989).

Datum Levels

Datum for levelling is zero of the tide staff established in 1988.

UH-1 (Oct 1989) -3.826m
UH-2B (Oct 1989) -3.595m
UH-3B (Oct 1989) -6.483m

Additional Information

Even though the station at Nauru was installed in 1974, the initial benchmarks were not levelled until November 1976. Photos of benchmarks from the October 1989 levelling are available.

Quality Assessment by the UH Sea Level Center

Comment

The daily and monthly means reveal no apparent changes in the reference level and agree well with Kapingamarangi and Tarawa. The daily means and the hourly residuals show significant fluctuations with a period around a day associated with surges in the west- facing harbor in response to westerly winds.

The timing accuracy is no better than plus or minus 8 minutes prior to 1980.

Gaps filled with NTF data noted by * below.

Year CI(%) Missing Data Replaced Gaps or Bad Data Questionable Fluctuations
        146-150,170-174, 200-202,229-230
1975 86 1-33,204-205,233-243,354-357 (14)176-(04)177 62,67-77,82-90,99-106,111-118,127-135,
1976 98 351-356 none 47,134-135,148-152,210-211,227,253,298
1977 83 2-20,32-50,77-81,87-89,96-99,352-355 none 1-2,82-85,148-151,180-181,209-212,239
1978 73 3-35,65-116,197-208 258,287-293,303-309 none 35-41,246-249,256-
1979 87 45-64,69-73,90-93,280-281,348-365 (13)303-(12)304 (04)337-(03)338 1-2,15,23-32,40-45,67-69,73-76,85-88, 158-159,162,164- 165,173,174,180,190-193,235-236,245,293-297,306-307,312,320,335,337-342,347-348
1980 87 1-46 none 84-86,363-364
1981 97 232-236,247-253 none 68-71
1982 100 none none 53,88,183-184,199-200,239,317-318
1983 100 none none 327
1984 100 none none 75-76
1985 98 7-11 none none
1986 100 none none 29-30,134,321-322,326,343-345,347-348
1987 100 none none 54-55,190,196
1988 100 none none 79-80
1989 100 none none none
1990 100 none none 73,235-236,320,322-324,352
1991 99 323-324 (10)278-(00)279 (06)285-(22)285 none
1992 100 none none none
1993 96 70-83,121-122,154-155,186-187 (02)105-(19)105 *(00)266-(23)274 none
1994 100 215-216,250-251,301-308,344-349 *(00)215-(23)216 *(00)250-(23)251 *(00)301-(23)308 (00)309-(12)309 *(00)344-(23)349 none
1995 67 5-121,355-356,363-365 none none
1996 91 1-8,12-18,69-79,95-96,155-166 none none
1997 100 none none none
1998 99 43-45,272-273 none none
1999 100 none none none
2000 99 61-62,66-69 none none
2001 99 76-77 none none