Harmonic analysis of tidal data with missing values based on the least squares method.

Abstract

Principally, if the observed period is one year, a set of 60 harmonic constants can be analyzed using hourly tidal data with a large amount of missing values by the least squares method of tidal harmonic analysis. In this paper, the response of the harmonic constants to the amount of missing values using tidal observation data at a tide gauge is investigated. It is shown that harmonic constants are robust in the case of sporadic missing values, of which the proportion is less than 80％ of the observations. It is also shown that harmonic constants are robust in the case of continuous missing values, of which the proportion is less than 30％ of the observations.