Quepos (Costa Rica) Site History

History Summary

Reference Level

The data have been linked to tide staff zero by the contributors. However, further analysis of the data has led to adjustments of the reference level in separate segments.

All suspected shifts showed step function jumps in the plots of hourly residuals and of differences of daily values with the nearest stations. These adjustments contain uncertainty to a few centimeters.

Tide Gauge Benchmark (TGBM) Description

BM-1-Q (disco de 9cm diam., en bastion concreto del muelle). En Quepos la marca se encuentra colocada 2.4metres al Sur extremo Norto del bastion de concreto en la extrada del muelle (4.8832m above IGN datum).

Auxilliary Benchmarks

Punta A: half a bolt welded in angle iron brace on tide staff (4.9417m above IGN datum)

BM-2-Q (5.8419m above IGN datum) BM-3-Q (5.1293m above IGN datum)

BM-3-Q (5.5495m above IGN datum) BM-5-Q (2.4525m above IGN datum)

Benchmark Relationships

Tide gauge zero (TGZ) = 2.8312m below IGN datum

TGZ = 7.7729m below punta A

TGZ = 7.7144m below BM-1-Q

Quality Assessment by the UH Sea Level Center

Comments

The data from the standard analog gauge showed many distinct shifts at the beginning of some months throughout the record. All obvious shifts have been adjusted as noted above. However, the long-term reference level stability is uncertain.

The analog data from 1 April 1988 - 30 September 1990 were replaced with ADR data which also have been linked to tide staff zero. The ADR data were used to fill small gaps in the analog record (see '#' below) and analog data were used to fill gaps in the ADR (see '*' below).

Data from 1 - 17 June 1991 appear 15 cm high.

Severe timing errors associated with gauge problems occurred from September - November 1985. The timing has an uncertainty of about ±7 minutes. The hourly residuals of the ADR data show considerable noise; thus the hourly ADR data are of less quality than the daily or monthly ADR data.

As of 4/92, the FP ADR is the primary gauge.