Short-term hydromorphodynamics and sediment volume in mixed-energy urban beaches on the northeastern Brazilian coast

Morphological changes in beach environments are influenced by natural factors that play a fundamental role in shaping coastal morphodynamics. This study assessed short-term sedimentation dynamics and morphodynamic responses driven by wave-induced hydrodynamics during the construction of the Tambaú Hotel along Tambaú and Manaíra beaches, in João Pessoa, northeastern Brazil. To analyze hydromorphodynamic processes under anthropogenic influence, an integrated approach was adopted, combining field measurements, grain-size analysis, multiple datasets, and numerical simulations using SMC-Brasil. Given that the study relies on field data from 2008–2009, short- and long-term accretion trends, as well as erosion risks, may be partially obscured or underestimated. The results indicate that Manaíra Beach consistently exhibited higher significant wave heights and littoral current velocities compared to Tambaú Beach, confirming its greater hydrodynamic energy and morphodynamic variability. Although cross-shore profiles provide essential insights into beach morphodynamic behavior, pronounced cyclical vertical sediment exchange between the backshore/swash zone and the lower shoreface persists. Granulometric analysis revealed distinct spatial patterns across the analyzed profiles. The construction of the Tambaú Hotel significantly altered local sediment transport dynamics.