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Abstract. Barrier islands are low-lying coastal landforms vulnerable toinundation and erosion by sea level rise. Despite their socioeconomic andecological importance, their future morphodynamic response to sea level riseor other hazards is poorly understood. To tackle this knowledge gap, weoutline and describe the BarrieR Inlet Environment (BRIE) model that cansimulate long-term barrier morphodynamics. In addition to existing overwashand 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, andbuild flood–tidal delta deposits. Long-term simulations reveal complexemergent behavior of tidal inlets resulting from interactions with sea levelrise and overwash. BRIE also includes a stratigraphic module, whichdemonstrates that barrier dynamics under constant sea level rise rates canresult in stratigraphic profiles composed of inlet fill, flood–tidal delta,and overwash deposits. In general, the BRIE model represents a process-basedexploratory view of barrier island morphodynamics that can be used toinvestigate long-term risks of flooding and erosion in barrier environments.For example, BRIE can simulate barrier island drowning in cases in which theimposed sea level rise rate is faster than the morphodynamic response of thebarrier island.
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EXPLORING CENTENNIAL BARRIER-INLET EVOLUTION: INSIGHTS FROM UNDEVELOPED AND DEVELOPED PHASES AT BARNEGAT INLET, NEW JERSEY
This study aims to identify the natural processes and the subsequent responses to coastal engineering and development on the alongshore evolution of the IB-BI-LBI inlet-barrier system. The primary focus will be the quantification of barrier island and inlet sediment partitioning at decadal to centennial timescales, from 1839-1941. We analyze historical alongshore evolution and track coastal engineering efforts at the Island Beach–Barnegat Inlet–Long Beach Island, NJ barrier-inlet system, which has transitioned from natural to highly developed over the past 180 years. We build a quantitative mass-balance framework that tracks sediment reservoir volumes and transport fluxes within the barrier-inlet system to describe both the natural and developed alongshore evolution of this system. We find that minor coastal engineering efforts, including the construction of small-scale wood and stone jetties, not only shift sediment transport locally, but also shift system-wide sediment transport based on inlet-barrier island interactions and sediment partitioning. Better understanding these different modes of past evolution can help to guide coastal management strategies as beach nourishment increases in cost, sea level-rise accelerates, and extreme storm patterns change.
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- Award ID(s):
- 2103754
- PAR ID:
- 10433798
- Date Published:
- Journal Name:
- Coastal Sediments 2023
- Volume:
- 1
- Issue:
- 1
- Page Range / eLocation ID:
- 1403 to 1414
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1142/9789811275135_0130
