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We evaluate and compare the performance of Bayesian Monte Carlo (BMC), Markov chain Monte Carlo (MCMC), and the Generalized Likelihood Uncertainty Estimation (GLUE) for uncertainty analysis in hydraulic and hydrodynamic modeling (HHM) studies. The methods are evaluated in a synthetic 1D wave routing exercise based on the diffusion wave model, and in a multidimensional hydrodynamic study based on the Environmental Fluid Dynamics Code to simulate estuarine circulation processes in Weeks Bay, Alabama. Results show that BMC and MCMC provide similar estimates of uncertainty. The posterior parameter densities computed by both methods are highly consistent, as well as the calibrated parameter estimates and uncertainty bounds. Although some studies suggest that MCMC is more efficient than BMC, our results did not show a clear difference between the performance of the two methods. This seems to be due to the low number of model parameters typically involved in HHM studies, and the use of the same likelihood function. In fact, for these studies, the implementation of BMC results simpler and provides similar results to MCMC. The results of GLUE are, on the other hand, less consistent to the results of BMC and MCMC in both applications. The posterior probability densities tend to be flat and similar to the uniform priors, which can result in calibrated parameter estimates centered in the parametric space.

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Wave-induced streaming of fluid mud at open coasts under damped, nonbreaking waves is examined as a likely mechanism to explain nearshore bottom evolution in such an environment. For a two-layered, water-fluid mud domain in which mud is considered to be a viscous continuum, an expression for the streaming velocity is obtained. Preliminary data on alongshore streaming of fluid mud in a wave basin show an order of magnitude agreement with theory. Previous observations on the rates of mud movement along the coasts of Surinam, Guyana and Louisiana are shown to yield alongshore velocities that are commensurate with those obtained by considering streaming to be the prevalent cause of mud transport. These velocities are considerably lower than those which would occur due to breaking waves. Off the southwestern coast of India, shoreward streaming of mud under monsoonal waves results in the formation of shore-fast mudbanks. It is argued that among transport mechanisms which govern the dynamics of microtidal muddy coasts, streaming may be an important means by which fluid mud influences the formation, migration and dissipation mudbanks in areas where wave breaking is significantly attenuated by viscous damping.