Inlet connectivity as new concept to understand the role of tidal divides in mesotidal barrier coast dynamics

Whether and how the inlets in mesotidal barrier coasts (e.g., Long Island, Ria Formosa, Venice Lagoon, Wadden Sea) affect one another morphodynamically is not<br/>only theoretically, but also practically relevant. For example, dredging operations in one inlet may trigger sedimentation at another inlet. Based on Escoffier's [1] cross-sectional inlet stability principle, past studies explored the possible return to equilibrium after perturbing one or more inlets [2]. However, inlet stability neglects the degree to which inlets influence each other. This calls for a new concept, here referred to as inlet connectivity, that is likely to depend on various characteristics, such as back-barrier geometry, inlet spacing and tidal divides. Here we (i) introduce and quantify this new concept, and moreover (ii) implement and analyse it in an exploratory double inlet model, extended to include a tidal divide (Fig. 1a).