Kwajalein (Marshall Island) Site History

History Summary

Reference Level

All heights have been referred to the station tide staff zero which is linked to fixed benchmarks. Based on residuals, a level shift was adjusted by adding -60 mm to 18Z 29 December 1950 to 12Z 31 December 1951. Differences with the PSMSL holdings suggest 1957 data high by 2 cm.

Tide Gauge Benchmark (TGBM) Description

Benchmark 8(1957) is the primary benchmark (PBM), and set in the north side of the former sea wall of Echo Pier.

Benchmark relationships

TGBM is 9.36ft above Tide Gauge Zero (Station Datum).

NOAA Chart Datum (MLLW) is 2.83ft above Station Datum.

Mean Sea Level (1960-1978) is 4.73ft above Station Datum.

Quality Assessment

Comments

The daily and monthly means reveal no apparent reference level changes or trends and agree with the nearest station, Majuro. The timing is no better than about ±5 minutes prior to 1976.

The data for 1996-2000 were supplied with heights relative to MLLW. Consequently 863mm was added to refer the data to tide gauge zero.

The data for 1998-2000 were supplied in non-GMT format and had to be shifted into GMT.

Notable episodic events:

• 04-06 November 1952: Tsunami from Kamchatka
• 23-25 May 1960: Tsunami from S.C. Chile