RT journal article
T1 Impacts of El Niño on the sediment balance of a transgressive dune-beach system
A1 Ruiz de Alegría-Arzaburu, A.
A1 Costas, S.
A1 Delgado Fernández, Irene
A2 Ciencias de la Tierra
K1 Morphodynamics
K1 Sediment transport
K1 Storms
K1 Shoreline evolution
K1 Shoreface
K1 Beachface
AB Understanding long-term evolution of sandy coasts requires in-depth analysis of the sediment balance from theshoreface to the beach and dune. While storms typically erode the subaerial beach, they can also contributesediment from deeper waters to the coastal budget. Here, we explore the impacts of El Nino-driven ˜ storms on thesediment balance across the entire shore-beach-dune profile. Satellite-derived shorelines (1984–2020) werecombined with sixty-six topo-bathymetric surveys (2014–2020), along a 1 km stretch of southern Ensenadabeach (Baja California). Forcing conditions were characterized using hourly wave and wind data. Multi-decadalshoreline data reveal that high-energy El Nino ˜ events have led to punctuated landward coastline translation.Interannual topo-bathymetric surveys show an active 8 to 9.5 m-high dune ridge along the upper part of theprofile, migrating landward at a rate of 5 m/yr. This migration gradually decoupled the dune from the beach,occasionally creating space across the dune toe area for the formation of incipient dunes that eventually mergedwith the main ridge. The sediment budget analysis indicates a one-way landward transfer of sediment from thewinter-berm to the dune. Interestingly, the overall shore-beach-dune sand budget remained positively balanced,with an increase of ≈40 m3/m related to sediment availability from deeper waters and onshore transport fromthe lower shoreface. Shoreline trends and sediment budgets illustrate a long-term transgressive system capable of maintaining sedimentary balance in the mid-term. Increased storm activity and sea-level rise are expected toaccelerate beach-dune transgression, which could retain sediment balance if offshore inputs persist.
PB Elsevier
SN 1879-1026
YR 2025
FD 2025-08-28
LK http://hdl.handle.net/10498/38606
UL http://hdl.handle.net/10498/38606
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 10-may-2026