Author(s): Manel Grifoll; Alan Cuthbertson; Jarle Berntsen
Linked Author(s): Alan J S Cuthbertson
Keywords: Salt-wedge estuary; Modelling; Stratified flow; Salt intrusion; Ebro Delta
Abstract: Topographic features in salt-wedge estuaries are known to have a primary influence in limiting the extent of salt wedge intrusion into the estuary and the positioning and sharpness of the density interface between the intruding salt water and overlying freshwater layers. In field studies, Ibañez et al. (1997) noted that channel bathymetry influenced the advancement and retreat of salt wedges observed in the Ebro and Rhone River estuaries (within the NW Mediterranean Sea region). Seminal studies on arrested salt wedge (ASW) dynamics by Arita and Jirka (1987a,b) also provided a theoretical two-layer model for ASW development, accounting for interfacial friction and entrainment effects. However, description of bottom boundary friction effects associated with topographic features, and their interaction with salt wedge penetration and interface dynamics, are still not fully understood in ASW estuaries. As such, the current study applies a numerical model to investigate the impact of bottom topography on interface stability and salt-wedge penetration both within a real estuary (i.e. Ebro Delta) and for different idealized geometries.
Year: 2025