Rothera Phase 1 Site History
History Summary
| Station Name | Rothera Phase 1 |
|---|---|
| Latitude | 67° 34.3' S |
| Country | U.K. |
| Longitude | 068° 07.7' W |
| WOCE No | 9100 |
| Time Reference | GMT(00-23 hours) |
| Contributor | Proudman Oceanographic Laboratory,
Joseph Proudman Building, 6 Brownlow Street, Liverpool, L3 5DA. U.K. |
| Observation Period | Nov 1992 - Oct 1999 |
| Instrument Type | 1992 - 1994 Aanderra WLR PTR475 1994 - 1999 Aanderra SRL/WLR |
| Site of Gauge | Sea water well |
Parameters recorded
| Period | Parameters | Sample Interval |
|---|---|---|
| 11 1992 - 03 1993 | ST,SSP,PR | 60 mins |
| 12 1993 - 12 1994 | ST,LT,AP,SSP,HTP | 15 mins |
| 01 1995 - 12 1995 | ST,LT,AP,SSP,HTP | 15 mins |
| 01 1996 - 11 1996 | ST,LT,AP,SSP,HTP | 15 mins |
| 01 1997 - 12 1997 | ST,LT,WT,AP,SSP,HTP | 15 mins |
| 12 1997 - 11 1998 | ST,LT,WT,AP,SSP,HTP | 15 mins |
| 12 1998 - 10 1999 | ST,LT,WT,AP,SSP,HTP | 15 mins |
where
- ST = TEMPPR01 = Sea Temperature
- PR = PRSTRS01 = Residual
- LT = CTLGPR01 = Logger Temperature
- WT = TEMPPH01 = Well Temperature
- AP = CAPHSL01 = Atmospheric Pressure
- SSP = PRSTPS01 = Sub Surface (total) Pressure
- HTP = PRSTPH01 = Half Tide (total) Pressure
Completeness Index
| Year | CI (%) | Year | CI (%) |
|---|---|---|---|
| 1992 | 11.2 | 1993 | 76.2 |
| 1994 | 91.0 | 1995 | 53.7 |
| 1996 | 99.4 | 1997 | 100 |
| 1998 | 98.8 | 1999 | 75.1 |
Note: In 1998 91% of the data were corrupted (Quality Index 7.4%)
Datum Information
Not yet available.
Quality Assessment
All data have been tidally analysed and constants and residuals checked. Records have been visually inspected for spikes and datum shifts.
December 1992 to December 1994
| Period | Parameters | Comments |
|---|---|---|
| 11 1992 - 03 1993 | SSP | No gaps (>6 hrs) |
| All | No spikes or gaps.
Data time shifted by -2.00 hrs, for harmonic constants to agree with those from later records. |
|
| 12 1993 - 12 1994 | SSP | Gaps: 87-97(1994),334-335(1994),337-339(1994) |
| All | Detailed in the following table |
Spikes and Gaps December 1993 to December 1994
| Start | End | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Scan | Flag | Year | Day | Hour | Scan | Flag | Year | Day | Hour | Reason for Flag/Solution |
| 1 | 1 | 93 | 342 | 1.875 | 42 | 1 | 93 | 342 | 12.125 | Datum correction in HTP record. Corrected by adding 147 mb to first 41 values, then correcting spike at scan 42. |
| 150 | 1 | 93 | 343 | 15.125 | 210 | 1 | 93 | 344 | 6.125 | Spikes + floor problems in HTP record 'corrected' by relating to SSP record |
| 241 | 1 | 93 | 344 | 13.875 | 242 | 1 | 93 | 344 | 14.125 | Spikes in ST record, solved by interpolation. |
| 243 | 1 | 93 | 344 | 14.375 | 249 | 1 | 93 | 344 | 15.875 | Dropout on all channels, filled using interpolated values. |
| 250 | 1 | 93 | 344 | 16.125 | 263 | 1 | 93 | 344 | 19.375 | ST record problems. Corrected by interpolation |
| 483 | 1 | 93 | 347 | 2.375 | 510 | 1 | 93 | 347 | 9.125 | HTP gauge. Problem with peak + cut off. Filled by relating to SSP record |
| 570 | 1 | 93 | 348 | 0.125 | 613 | 1 | 93 | 348 | 10.875 | HTP tide gauge. Problem with peak + cut off. Filled by relating to SSP record |
| 662 | 1 | 93 | 348 | 23.125 | 726 | 1 | 93 | 349 | 15.125 | HTP gauge. Problem with peak + cut off. Filled by relating to SSP record |
| 1050 | 1 | 93 | 353 | 0.125 | 1051 | 1 | 93 | 353 | 0.375 | Spike in HTP signal. Replaced by interpolating. |
| 1240 | 1 | 93 | 354 | 23.625 | 1268 | 1 | 93 | 355 | 6.626 | HTP gauge. Problem with peak + cut off. Filled by relating to SSP record |
| 10629 | 1 | 94 | 87 | 18.879 | 11587 | 1 | 94 | 97 | 18.380 | Dropout on all channels (break in record). Values not filled. |
| 26159 | 1 | 94 2 | 49 | 13.385 | 26160 | 1 | 94 | 249 | 13.635 | Spike in HTP record. Replaced by interpolated value |
| 29352 | 1 | 94 | 282 | 19.637 | 29365 | 1 | 94 | 282 | 22.887 | Spikes in SSP record. Replaced using interpolated values |
| 34347 | 1 | 94 | 334 | 20.389 | 34373 | 1 | 94 | 335 | 2.889 | Dropout in record. SSP and AP filled by interpolation. Other channels left blank. |
| 34526 | 1 | 94 | 336 | 17.139 | 34549 | 1 | 94 | 336 | 22.889 | Dropout on all channels. SSP, AP and HTP channels filled by interpolation |
| 34598 | 1 | 94 | 337 | 11.139 | 34789 | 1 | 94 3 | 39 | 11.000 | Dropout on all channels. Gap too large to fill. |
Harmonic analysis of the file gives excellent agreement with later files, suggesting that overall, the timings are good.
Datum of HTP gauge drifts 30 mb over first 5000 scans, before settling. Appear to have some sort of 'overshoot' in HTP record between scans 17000 and 23000. Over the whole record, there's a steady drift in HTP datum of 4 mbar. Comparing the SSP and HTP sensors suggests that 3 mbar of this drift is due to the HTP sensor.
January to December 1995
| Period | Parameters | Comment |
|---|---|---|
| 01 1995 - 12 1995 | All | Gap : 62-227(1995) |
Agreement between HTP and SSP, over the high water period, is quite poor, prior to the gap in the data. There is a variability of approximately 1.5 mbar, and an offset of of 3 mbar between the two signals.
Comparing HTP and AP, the HTP cut off is very well defined prior to the gap in the data. There are some spikes, however only on one occasion, is this greater than 1 mbar. Following the data gap, the HTP record is very 'noisy' until day 280, where there is an apparent datum shift. The recorded pressure difference at LW, varies between 224-226 mbar.
The residuals appear very good. There is a spike at day 299, and a drop out between day 335(14.875) - day 336(19.625) which has not be infilled. Day 339 (16.125 - 16.375) has been corrected, with data based on the harmonic analysis predictions.
Harmonic constants agree well with the other files.
January to November 1996
| Period | Parameters | Comment |
|---|---|---|
| 01 1996 - 11 1996 | All | Gaps : None |
| SSP | Spikes : 205-275 | |
| HTP | Spikes : 175,205-243 |
HTP definition is very poor, until day 135. As comparisons between AP and LW HTP are generally good, it appears that there may be a problem with the SSP.
Residuals appear excellent, harmonic constants are in good agreement with the other data.
January 1997 to December 1997
| Period | Parameters | Comment |
|---|---|---|
| 01 1997 - 12 1997 | All | Gaps : None
Spikes : None Timing : 335 onwards - see note below. |
Comparing HTP and AP gives a 12.7 mbar offset at LW. HTP cut-offs are generally well defined, although there are some overshoots.
SSP and HTP show differences between the observed full tide at times.
Residuals look excellent until day 335, when it looks like there is a timing error. Harmonic constants are in excellent agreement with other files.
December 1997 to November 1998
| Period | Parameters | Comment |
|---|---|---|
| 12 1997 - 11 1998 | SSP data very poor, due to sensor flooding. HTP data appears reasonable. |
It is recommended these data not be used. However, it maybe possible to reconstruct the signal from the HTP sensors using predictions to infill the low tide.
December 1998 to October 1999
| Period | Parameters | Comment |
|---|---|---|
| 12 1998 - 10 1999 | SSP | Gaps : 361 (1998) Infilled by interpolation
Sensor failed : 261 (1999) All Gap : 361 Sensors failed: HTP 275(1999), AP 274 (1999) ST 265 (1999) |
Comparison between HTP and AP, also SSP and HTP indicate a 2 mbar drift on the HTP sensor over the period of the data.
Residuals show intermittent timing errors. Harmonic contstants are in excellent agreement with previous data files.
