Groundwater response to tidal forcing

Abstract

The groundwater response to tidal forcing in a phreatic aquifer is modelled using a perturbation approach for the case of a shallow beach. The principal features of the groundwater response, namely the super-elevation of the water table, attenuation of the forcing wave and the asymmetry and phase shift in the fluctuations, is investigated and compared with earlier solutions. These results demonstrate the importance of correctly including the beach slope effects to prevent the exaggeration of observed features for shallow beaches. A general solution method is presented, which provides an efficient method for obtaining higher order solutions. References

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