Arica (Chile) Site History

History Summary

Station Arica
Country Chile
Latitude 18° 28.0' S
Longitude 070° 20.0' W
WOCE No 9001
Time Reference GMT (hours 00-23)
Contributor Servicio Hidrografico y Oceanografico de la Armada (SHOA)
Instrument Type Standard mechanical (10/1982 - 12/1985)
Metercraft bubbler (12/1985 - present) (primary)
Handar Encoder model 436A (11/1986-present)(back-up)
Site of Gauge  
Observational periods 1982 - present

Reference Level

The originators have related the data to tide staff zero which is linked to a fixed set of benchmarks. Specifically, BM #1 (established 1950) is used as a historical datum. However, original data as received from SHOA were adjusted with the SHOA station leveling data as follows.

Period (day/month/year) Value added to original(mm)
*14/07/1983 - 31/08/1983 -140
09/06/1987 - 31/12/1987 504
23/10/1990 - 25/10/1990 130
&28/07/1993 - 27/09/1993 -55

*Adjustment of shift in reference level deduced from the plot of hourly residuals and from comparison of daily values with Antofagasta and Caldera.

&Based on comparisons with satellite-received data at the University of Hawaii and comparisons among neighboring sites.

These adjustments contains uncertainty of a few centimeters.

Data from 1988-1990 were received with the reference level tied to the BM #1 (1950) while data for other time periods were received without linking the data to BM #1. Thus, the following level adjustments have been applied to the original data based on SHOA geodetic level records.

Period (day/month/year) Value added to original(mm)
01/01/1982-31/12/1987 -256
01/01/1991-24/04/1995 243
24/04/1995-31/12/1996 -460
01/01/1997-31/12/1998 -217

Quality Assessment by the UH Sea Level Centre

Comment

The daily and monthly values agree well with the nearest station, Antofagasta, and there are no obvious reference level shifts, except that mid-July 1992 to Dec 1992 appears about 5 cm low and 28 July - 27 September 1993 appears about 6 cm high compared with other sites and the satellite-received data for same time period. # below indicates gaps filled with Bubbler data received at the UH Sea Level Center via satellite and $ below refers to gaps filled with Encoder data.

Year CI(%) Missing Data Replaced Gaps or Bad Data Questionable Fluctuations
1982 24 1-275 (21)237-(11)238 296,318
1983 86 1-40,61-74 (21)120-(03)121 (03)195-(01)196 (16)212-(03)213 (21)267-(13)268 56-60,182-183
1984 88 31-67,111-116 none 120
1985 94 87-88,181-201 (16)030-(13)031 (22)173-(13)174 (16)243-(03)244 (14)273-(03)274 63,80,123-124
1986 100 none (01)237-(13)237 (14)365-(23)365 none
1987 100 none (15)089-(13)090 (04)161-(03)162 none
1988 100 none (14)014-(13)015 (21)066-(13)067 (06)068-(13)068 (23)069-(06)070 (21)131-(12)132 (06)183-(16)183 (01)188-(12)188 (04)189-(02)190 (15)275-(21)275 (20)331-(11)332 #(05)002-(12)004 #(23)061-(07)064 #(14)092-(05)095 #(15)149-(13)152 #(05)157-(05)158 #(10)184-(02)186 6-7,64-65,95-96
1989 100 none (04)099-(13)099 (11)168-(03)169 (05)275-(12)275 (21)317-(14)318 #(13)091-(14)092 #(04)172-(13)188 #(01)196-(18)198 none
1990 99 334-336 (23)328-(13)329 (01)351-(14)351 #(23)020-(13)023 #(05)121-(13)122 #(19)138-(15)141 #(16)334-(06)336 15-17
1991 100 none #(02)142-(13)143 none
1992 100 none (17)124-(11)125 (14)293-(13)294 184-185,249-252,269-270,302-303
1993 100 none (15)005-(14)006 (01)067-(13)067 (18)090-(23)090 (01)091-(11)091 #(00)333-(18)340 38-39
1994 100 none $(08)058-(23)059 (16)117-(13)118 (20)313-(11)314 (19)328-(06)329 (21)329-(04)330 (16)331-(12)332 none
1995 99 251-253 (14)069-(13)070 $(00)074-(23)092 (15)121-(03)122 $(00)213-(12)218 $(12)306-(23)308 (19)316-(12)317 $(00)350-(23)351 none
1996 99 366 (00)082-(12)082 $(00)094-(23)097 $(00)112-(23)116 $(00)217-(23)218 $(00)226-(23)227 (04)306-(13)306 $(12)356-(23)361 none
1997 100 none $(00)001-(15)002 $(23)010-(12)016 $(31)031-(11)034 $(04)041-(12)062 $(21)064-(17)069 $(15)075-(15)076 (14)087-(12)088 (20)117-(13)118 (12)119-(03)120 (05)296-(13)296 (06)298-(13)298 (00)299-(16)299 (22)299-(19)300 (22)300-(16)301 (22)301-(19)302 (02)334-(14)334 (05)341-(12)341 none
1998 100 none (00)001-(18)001 (17)034-(12)035 (22)092-(12)093 (21)193-(14)194 (04)195-(19)195 #(00)274-(23)283 none