QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 25 Jul 2000 Station : Puerto Williams Latitude: 54 56.0S Country : Chile Longitude: 067 37.0W JASL # : 287A Time Meridian: 060W (GMT - 4 hr) GLOSS # : none Originator #:1220 NODC #: 55064701 Contributor : Servicio Hidrografico y Oceanografico de la Armada (SHOA) Casilla 324 Valparaiso CHILE Originator : same Original Data: analog Instrmnt Type: float and well, standard mechanical (1985-1989); Metercraft bubbler (1990-) Digitzd Intvl: one hour Present Data : Hourly, daily, and monthly values obtained by: Hourly : The original digitizing interval was hourly 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 : 01 Jan 1985 - 31 Dec 1999 Gaps > 1 mon : 27 Jan 1990 - 01 Mar 1990;15 Dec 1991 - 14 Feb 1992 01 May 1995 - 01 Jul 1995;31 Dec 1995 - 01 Apr 1995 01 Feb 1998 - 01 Mar 1998;01 Jan 1999 - 21 Jul 1999 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : No Distribution : 1985-1998 Refernce Levl: The originators have related the data to tide gauge zero which is linked to a fixed set of bench marks. Several short segment with obvious level shifts were adjusted as noted here: value added period((hour)dd/mm/yyyy) to original(mm) ----------------------------- --------------- (19)31/05/1985-(19)30/06/1985 -370 (00)01/07/1987-(23)03/08/1987 300 (13)08/08/1987-(05)10/08/1987 -400 (21)18/08/1987-(15)20/08/1987 350 These adjustments contains uncertainty of a few centimeters. Tide gauge benchmark (TGBM) description: BM control - BM No. 2 - It is a 9cm bronze disk stamped CF 2, set in cement at the south west corner of the warehouse located 30m east of the passenger pier and 6m south of the 'Avenida Costanera'. Auxiliary benchmarks: BM No. 3 - it is a 6cm bronze disk stamped CF3 set in cement at the north east corner of the warehouse located 60m east of the passenger pier and 2m south of the 'Avenida Costanera'. Benchmark relationships: BM No. 2 1966-1990 BM No. 3 1966-1990 Comment : High energy with periods ~days dominate the signal. Anomalously high mean values exist during 12/1987-02/1988. Except for a few periods with timing errors and short gaps, the data are of good quality. Data for 1999 appear to have a mean about 20 cm high. An error in calibration is suspected. This feature is under investigation by SHOA. Use the 1999 data at your discretion. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1985 94 1,15-16,84-100,114- (17)104-(03)105 none 115,118-119 (17)243-(23)243 (03)284-(13)284 (22)305-(13)306 1986 91 23-27,335-365 (06)032-(14)032 none (03)089-(13)089 (18)261-(13)262 (04)314-(21)314 1987 99 1,66-68,181-182, (14)024-(13)025 2-3 348-349 (14)059-(23)059 (01)060-(13)060 (13)091-(23)091 (15)142-(13)143 (06)203-(13)203 (21)215-(13)216 (06)222-(13)222 (05)242-(12)242 (01)244-(13)244 1988 99 16-17 (08)095-(15)095 183-184,190,297-301, (17)241-(13)242 321-327 (04)253-(13)253 (20)282-(16)283 (22)303-(12)304 (23)304-(13)305 1989 95 68-76,91-96,231-237 (04)001-(14)001 none (03)002-(13)002 (19)060-(18)061 (15)182-(13)183 (01)197-(13)197 (05)198-(13)198 (04)213-(13)213 (01)299-(18)299 1990 90 27-60,352-355 (04)002-(13)002 none (06)075-(13)075 (02)305-(10)305 1991 95 213-214,330-331, (03)001-(14)001 331-334 349-365 (14)110-(13)111 (22)261-(13)262 (17)278-(13)279 (23)322-(13)323 1992 87 1-45,67-68 (12)061-(23)061 none (01)061-(11)061 (18)200-(14)201 (01)213-(11)213 (20)339-(03)340 1993 96 152-154,163-165,194- (04)001-(13)001 none 195,325-326,355-363 (07)063-(14)063 (22)128-(16)129 1994 98 2-3,61-62,334-335, (23)017-(13)018 none 365 (04)027-(03)028 (05)041-(13)041 (07)044-(14)044 (13)059-(23)059 (01)060-(12)060 (04)091-(03)092 (19)151-(23)151 (18)243-(23)243 1995 78 1,61-62,121-182,192- (01)060-(10)060 none 198,219-223,300-302, (04)244-(12)244 335-337,365 (16)246-(12)247 (13)304-(23)304 (01)305-(12)305 1996 75 1-92 (06)106-(13)106 none (18)156-(02)157 (08)157-(15)157 (18)157-(03)158 (09)158-(16)158 (19)158-(04)159 (19)210-(13)211 (05)242-(15)242 1997 99 220-223 (18)043-(13)044 none (20)103-(13)104 (01)155-(15)155 (00)156-(16)156 (05)163-(14)163 (10)165-(20)165 (05)176-(13)176 (21)234-(15)235 1998 90 32-60,135-142 (16)354-(13)355 none (22)363-(13)364 1999 41 1-202,241-248,275- none none 278,281-285,365