Wave refraction has an important role in the evolution and day-to-day behaviour of shorelines and beaches. It is often the major factor in dictating the magnitude and direction of the littoral drift.
The development of a wave refraction model for a particular site, (Poole/Christchurch Bays in the central south coast of England), is described. The computational technique is very powerful and an area of 2500 km2 of sea bed has been reproduced with the refraction behaviour superimposed for various wave directions and periods in deep water. In assessing the results, regard must be paid to the simplifying assumptions and the effects of offshore shoals.