# Inverse Modeling in Ocean Wave Studies

## Abstract

A fundamental description of sea state is provided by the surface wave directional spectrum. Efforts to measure the directional spectrum with *in situ* instrumentation generally yield data which represent estimates of integral properties of the spectrum. Extracting an estimate of the full, two-dimensional spectrum from such data presents a typical example of the so-called “inverse problem.” The problem is solved by finding a model spectrum which is statistically consistent with the observations and, at the same time, satisfies a set of externally imposed constraints required to make the problem determinate. We review here the theory of the linear inverse problem and its application to the estimation of surface wave directional spectra. The principles developed are then used to investigate the optimal analysis procedure proposed by Long and Hasselmann (1979).

## Keywords

Inverse Modeling Generalize Inverse Parameter Resolution Nonnegativity Constraint Cross Spectrum## Preview

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