Cocos Island (Keeling, Australia)Site History

History Summary

Station Cocos
Country Australia
Latitude 12° 07.0' S
Longitude 096° 53.0' E
GLOSS No 046
Contributor 1985-1988: TOGA Sea Level Center
1989-1998: National Tidal Facility, Flinders
Instrument Type Float and stilling well gauge,
Leupold and Stevens Analog-to-Digital Recorder
04/09/92-present NGWLMS (Acoustic gauge)
Site of Gauge The gauge is situated along the concrete wall on the jetty opposite the grass verge, on Home Island.
Observational periods 1985 - 2001

Reference Level

All data are referred to Tide Gauge Zero (TGZ) and linked into historic fixed benchmarks.

Tide Gauge Benchmark (TGBM) Description

PSM 101 The brass plaque is set in concrete at the base of the jetty on Home Island.
PSM 91 The brass plug is in the concrete wharf (northern wall), Home Island.
Trig R379 An RA Survey brass plaque is stamped R379, and is set in concrete at ground level, situated on the most SW point of Home Island, adjacent to the Clunies Ross Residence.

Benchmark relationships

Quality Assessment

Comment

The daily or monthly means do not reveal any obvious reference level shifts.

Since September 1992, atmospheric pressure has been measured at the tide gauge site. A daily signal has been observed in these data.

Year CI(%) QI(%) Missing Data Replaced Gaps or Bad Data Questionable Fluctuations
1985 6 6 none none none
1986 100 99 none none 45-52
1987 97 97 56-59,78-83,114-118,168-170 (17)027-(06)028 (12)180-(09)181 none
1988 58 57 52-53 none none
1989 90 90 none none none
1990 76 76 127-130,143-228 none none
1991 92 92 305-337 none none
1992 80 80 100-102,122-129,183-248 none none
1993 100 100 none none none
1994 100 100 none none none
1995 99 99 74-75 none none
1996 100 100 none none none
1997 100 100 none none none
1998 100 100 none none none
1999 99 100 50-52,53-55,59-60 none none
2000 100 100 none none none
2001 100 100 none none none