Abstract. Barrier islands are low-lying coastal landforms vulnerable to
inundation and erosion by sea level rise. Despite their socioeconomic and
ecological importance, their future morphodynamic response to sea level rise
or other hazards is poorly understood. To tackle this knowledge gap, we
outline and describe the BarrieR Inlet Environment (BRIE) model that can
simulate long-term barrier morphodynamics. In addition to existing overwash
and shoreface formulations, BRIE accounts for alongshore sediment transport,
inlet dynamics, and flood–tidal delta deposition along barrier islands.
Inlets within BRIE can open, close, migrate, merge with other inlets, and
build flood–tidal delta deposits. Long-term simulations reveal complex
emergent behavior of tidal inlets resulting from interactions with sea level
rise and overwash. BRIE also includes a stratigraphic module, which
demonstrates that barrier dynamics under constant sea level rise rates can
result in stratigraphic profiles composed of inlet fill, flood–tidal delta,
and overwash deposits. In general, the BRIE model represents a process-based
exploratory view of barrier island morphodynamics that can be used to
investigate long-term risks of flooding and erosion in barrier environments.
For example, BRIE can simulate barrier island drowning in cases in which the
imposed sea level rise rate is faster than the morphodynamic response of the
barrier island.