Coastal research over the past few decades has focused on hydrodynamics, sediment transport and morphodynamic processes in depositional coastal environments (beaches, shoreface and estuaries). However, a large proportion of the world’s coastlines, perhaps as high as 80 per cent, are rocky and characterised by cliff and/or intertidal shore platform topography.
In large tidal environments, such as the UK, these platforms tend to be gently-sloping seaward (<5˚), wide to very wide (100–500 m) and characterised by rough and dissipative surfaces. Cliffs and shore platforms are linked dynamically because shore platform characteristics (elevation, gradient, width and surface roughness) directly control the transformation processes of waves propagating across the platform, and thus the impact on the cliff. In large tidal environments, such as in the UK and Wales, shore platforms are wide (> 100 m), have gentle gradients (<5 ˚) extending into the subtidal zone and represent very rough surfaces. As a result, considerable wave energy losses occur as waves propagate across shore platforms. In combination with the water level, this wave transformation determines how much open-ocean wave energy is allowed to reach the base of the cliff, but this process is virtually unstudied within coastal engineering.
These wave transformation processes must be understood quantitatively to be able to predict coastal processes along rocky shores; therefore, the subject of the proposed research is to understand how waves propagate across shore platforms and develop a capability to reliably model this process. Our intention is to conduct comprehensive and detailed field measurements of wave transformation across six different shore platforms and under a range of wave/tide conditions, and derive universally valid principles from our observations that better describe and enable the prediction of wave transformation processes across rocky shore platforms.