Tristan da Cunha Phase 1 Site History
History Summary
| Station Name | Tristan da Cunha |
|---|---|
| Latitude | 37° 03.0' S |
| Longitude | 012° 18.0' W |
| Country | U.K. |
| Gloss No | 266 |
| Time Reference | GMT(00-23 hours) |
| Contributor | Proudman Oceanographic Laboratory, Joseph Proudman Building, 6 Brownlow Street, Liverpool, L3 5DA. U.K. |
| Observation Period | October 1984 - December 1998 (Site has not been visited to download data since Jan 1999) |
| Instrument Type | Oct 1984 - Oct 1986: Aanderaa bubbler Oct 1986 - Dec 1992: Digiquartz pressure sensor with telexed data transmission. (NB Note in Quality Assessment section below) Jan 1993 - Dec 1997: B-type Gauge (Woodworth et al. 1996) |
| Site of Gauge | Tristan da Cunha Harbour. |
Parameters Recorded
| Period | Parameters | Sample Interval |
|---|---|---|
| 10 1984 - 11 1985 | AP,SP | 60 mins |
| 11 1985 - 05 1986 | SP | 30 mins |
| 06 1986 - 10 1986 | AP,TP | 30 mins |
| 10 1986 - 10 1987 | ST,AP,TP,SSP | 15 mins |
| 10 1987 - 10 1988 | ST,AP,TP,SSP | 15 mins |
| 10 1988 - 02 1989 | ST,AP,TP,SSP | 60 mins |
| 02 1989 - 02 1990 | ST,AP,TP,SSP | 15 mins |
| 02 1990 - 10 1990 | ST,AP,TP,SSP | 15 mins |
| 10 1990 - 01 1992 | ST,AP,TP,SSP | 60 mins |
| 01 1992 - 12 1992 | ST,AP,TP,SSP | 15 mins |
| 01 1993 - 02 1994 | ST,SSP,HTP,SSP | 7.5 mins |
| 02 1994 - 02 1995 | ST,AP,SP,SSP,SSP | 15 mins |
| 02 1995 - 01 1996 | ST,AP,LT,SSP,HTP | 15 mins |
| 01 1996 - 12 1997 | ST,AP,LT,SP,SSP,HTP | 15 mins |
| 01 1998 - 12 1998 | ST,AP,LT,SSP,HTP | 15 mins |
where:
- ST = TEMPPR01 = Sea Temperature
- LT = CTLGPR01 = Data Logger Ambient Temperature
- SP = PRESPS01 = Sea Pressure
- AP = CAPHSL01 = Atmospheric Pressure
- SSP = PRSTPS01 or PRSTPS02 = Sub Surface (total) Pressure
- TP = PPSSRL01 = Total sub surface pressure - 1000.0
- HTP = PRSTPH01 Half Tide (total) Pressure
Data Return
| Year | Completeness Index(%) | Year | Completeness Index(%) |
|---|---|---|---|
| 1984 | 16.7 | 1985 | 98.6 |
| 1986 | 87.0 | 1987 | 99.5 |
| 1988 | 80.1 | 1989 | 88.5 |
| 1990 | 99.5 | 1991 | 98.9 |
| 1992 | 93.7 | 1993 | 92.1 |
| 1994 | 98.6 | 1995 | 99.9 |
| 1996 | 100 | 1997 | 99.5 |
| 1998 | 97.8 |
Datum Information
Not available
Quality Assessment
All data have been tidally analysed and constants and residuals checked. Records have been visually inspected for spikes and timing shifts. Timing and residuals appear satisfactory. However due to instrumentation drift, datum problems etc the contributor recommends, that these data should only be used for surges and short term variability and not for long term sea level studies.
Please Note for data Oct 1986 to Dec 1992. Datums for telexed transmitted data and logger recorded data, for the same period, differ. Telex transmitted data is 0.15 db higher than logger recorded data, the latter is assumed to be correct. Where files consist of a combination of both, telexed and logger recorded data, datum shifts are observed.
| Period | Parameters | Comments |
|---|---|---|
| 10 1984 - 11 1985 | AP | Gap: (1984)305 - (1985)001,(1985)215 - 323 |
| SP | Datum Shift: 02 May 1985 0700 hrs -0.2 dbars Datum Shift: 04 May 1985 0900 hrs +0.2 dbars Questionable Fluctuations: None | |
| 11 1985 - 05 1986 | SP | Gap: None Marked: (1986) 044,065,108,115 Questionable Fluctuations: None |
| 06 1986 - 10 1986 | AP | Gap: (1986)180 - 273 |
| SP | Gap: (1986)283 - 284 Questionable Fluctuations: None | |
| 10 1986 - 10 1987 | AP | Gap: (1987)270 - 278 |
| TP | Datum Shift: (1987) 270 see note above Datum Shift: (1987) 278 see note above Questionable Fluctuations: None | |
| 10 1987 - 10 1988 | AP | Gap: (1988) 104 - 293 |
| TP | Datum Shift: (1987) 104 see note above Questionable Fluctuations: None | |
| 10 1988 - 02 1989 | AP | Gap: (1988) 293, 314 - (1989) 039 |
| ST | Gap: (1988) 293, 314 - (1989) 0309 | |
| TP | Datum shift: (1988) 314 see note above Questionable Fluctuations: None | |
| 02 1989 - 02 1990 | AP | Gap: (1990) 038 Questionable Fluctuations: None |
| 02 1990 - 10 1990 | All | Gaps: None Questionable Fluctuations: None |
| 10 1990 - 01 1992 | AP | Gap: (1991) 115-120,266-274,274-275 |
| ST | Gap: (1991) 115-120,266-274,274-275 | |
| TP | Gap: (1991) 115-120,266-274,274-275 Questionable Fluctuations: None | |
| 01 1992 - 12 1992 | All Datum shift: (1992) 012 see note above | |
| ST | Marked: (1992) 94-95,160,161-162,170, 174,175-176,177,289,332 Questionable Fluctuations: None | |
| 01 1993 - 02 1994 | SSP | PRSTPS02 - Gap: (1993)099 - (1994)034 |
| HTP | Gap: (1993)099 - (1994)034 | |
| ST | Gap: (1993)099 - (1994)034 | |
| SSP | PRSTPS01 - None All Marked: None Questionable Fluctuations: None | |
| 02 1994 - 02 1995 | All | Gaps: None Marked: None Questionable Fluctuations: None |
| 02 1995 - 01 1996 | SSP | Gap: (1995)054 - (1995)055 |
| HTP | Gap: (1995)054 - (1995)055 | |
| ST | Gap: (1995)054 - (1995)055 | |
| 01 1996 - 12 1997 | All | Gaps: None Marked: None Questionable Fluctuations: None |
| 01 1998 - 12 1998 | SSP | Marked: (1998) 010,154-362 Questionable Fluctuations: 138-139 HTP Marked: (1998) 119-362 Half tide sensor does not always record the top of the tide. |
| ST | Marked: (1998) 119,128-362 | |
| AP,LT | Gaps: None Marked: None Questionable Fluctuations: None |
Reference
Woodworth, P.L., Vassie, J.M., Spencer, R. and Smith, D.E. 1996.
Precise datum control for pressure tide gauges. Marine Geodesy, 19(1), 1-20.
