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Wave intensities and slopes in Lagrangian seas

Part of: Stochastic processes Special processes Geophysics Geophysics (general)

Published online by Cambridge University Press:  01 July 2016

Sofia Åberg
Sofia Åberg*
Affiliation:
Lund University
*
∗ Current address: Matematiska vetenskaper, Chalmers tekniska högskola, Göteborg SE-412 96, Sweden. Email address: abergs@chalmers.se
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Abstract

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In many applications, such as remote sensing or wave slamming on ships and offshore structures, it is important to have a good model for wave slope. Today, most models are based on the assumption that the sea surface is well described by a Gaussian random field. However, since the Gaussian model does not capture several important features of real ocean waves, e.g. the asymmetry of crests and troughs, it may lead to unconservative safety estimates. An alternative is to use a stochastic Lagrangian wave model. Few studies have been carried out on the Lagrangian model; in particular, very little is known about its probabilistic properties. Therefore, in this paper we derive expressions for the level-crossing intensity of the Lagrangian sea surface, which has the interpretation of wave intensity, as well as the distribution of the wave slope at an arbitrary crossing. These results are then compared to the corresponding intensity and distribution of slope for the Gaussian model.

Keywords

Crossing theorywave steepnessGaussian processPalm distributionRice's formula

MSC classification

Primary: 60G60: Random fields
Secondary: 60G15: Gaussian processes 60K40: Other physical applications of random processes 86A05: Hydrology, hydrography, oceanography
Type
General Applied Probability
Information
Advances in Applied Probability , Volume 39 , Issue 4 , December 2007 , pp. 1020 - 1035
Copyright
Copyright © Applied Probability Trust 2007 

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