Dynamic Effective Porosity Explains Laboratory Experiments on Watertable Fluctuations in Coastal Unconfined Aquifers

Watertable fluctuations are a characteristic feature of coastal unconfined aquifers. They interact with the vadose zone creating dynamic effective porosity, for which new (empirical) expression is proposed based on dimensionless parameter related to fluctuation frequency. After comparing both experimental data and numerical simulations, implemented into modified Boussinesq equation, allowing examination effects porosity watertable fluctuations. The dispersion relation arising from equation predicts laboratory accurately, highlighting importance in modeling This turn confirms applicability real-valued porosity. An outcome that phase lag between total moisture (above watertable) height measured experiments using vertical soil columns (1D systems) can be ignored when predicting aquifers (2D systems). always smaller than so by comparison there reduction water exchange saturated zones. Consequently, waves propagate further landward without standing wave behaviors.