Uncertainty in Nearshore Sand Bar Migration

A coupled nearshore hydrodynamics and sediment transport model with adjoint-based uncertainty quantification has been applied to sand bar morphodynamics in the Duck94 field experiment (Duck, NC). The model, which is based on previously established physical process formulas, capable of producing accurate predictions migration during experiment. However, reasonable perturbations inputs—namely initial conditions, boundary calibration coefficients—can produce a range predictions. This taken represent potential for scenarios where one or more inputs are poorly constrained. Experiments presented that quantify relative impact different input types uncertainty, results contrasted accretive versus erosive wave conditions. During conditions (shoreward migration), dominated by growth errors owing positive feedbacks model. In contrast, (seaward there smaller instead coefficients. thus point qualitative differences nature morphodynamic under greater role internal error (positive feedbacks) physics being important