Modelling the Sea Surface of Cardigan Bay

Benjamin Churchill; Rebecca Caves; Chloe Peet; William Dawber

doi:10.59973/emjsr.136

Authors

Benjamin Churchill University of Portsmouth, School of Maths and Physics, Portsmouth, PO1 3FX
Rebecca Caves QinetiQ, Portsmouth, PO6 3RU
Chloe Peet QinetiQ, Portsmouth, PO6 3RU
Bill Dawber QinetiQ, Portsmouth, PO6 3RU

DOI:

https://doi.org/10.59973/emjsr.136

Keywords:

Wind Waves, Source Functions, Pierson-Moskowitz, JONSWAP, Significant Wave Height

Abstract

The aim of this project was to model the sea surface of Cardigan Bay, to be able to expand upon QinetiQ’s current wave models, used within their radar assurance activities. The sea surface can cause unwanted detections, which is referred to as clutter. The sea is not the only source of clutter such as litter and birds, have an impact on the returns detected by the radar. This project explored two different approaches, modelling the propagation of waves and modelling the distribution of energy across the sea surface. The first approach explored two open source models, WAVEWATCH III and SWAN, and after having technical errors, two real world, existing examples of where these models were implemented were researched. This research showed a lot of promise, and would be worth expanding upon. The second approach looked into two recognised equations for calculating the energy density of the waves, and then calculating the significant wave height. Overall, modelling the propagation of waves would produce more representative results, particularly SWAN which was a model designed for coastal waters, however to set up the wave models fell outside of the scope of this project.

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