Modelling of the wave-current interactions in Tagus estuary

A study of the wave propagation and of the consequences of the wave current interactions in the Tagus estuary is performed in the present work. Thus a couple of low tide and high tide subsequent situations, corresponding to an extreme energetic case, were considered. A Cartesian high-resolution SWAN grid was coupled to the wave prediction system developed in spherical coordinates. Using the ocean forcing this system provides the corresponding coastal transformation of the wave field, By introducing the Cartesian simulations, as a final extent of the system, some local processes as wave induced setup and diffraction can be also studied, and their relevance for this particular area is discussed. A balance between the accuracy of the results and the computational effectiveness was made by assessing the opportunity of using non stationary versus stationary simulations. However, the most important factors affecting the incoming waves are local currents and wind and their influences were evaluated and discussed.