Search

Your search keyword '"BARRIER-ISLAND EVOLUTION"' showing total 3 results
Start Over Descriptor "BARRIER-ISLAND EVOLUTION"
3 results on '"BARRIER-ISLAND EVOLUTION"'

1. An Integrated, Probabilistic Modeling Approach to Assess the Evolution of Barrier-Island Systems Over the Twenty-First Century

Author

Janaka Bamunawala, Ad van der Spek, Ali Dastgheib, A. Brad Murray, and Roshanka Ranasinghe

Subjects
barrier-island evolution, climate change, barrier drowning, probabilistic modeling, input uncertainties, Science, General. Including nature conservation, geographical distribution, QH1-199.5
Abstract

Barrier-island systems, spanning ∼7% of the world’s coastlines, are of great importance to society because not only they provide attractive, liveable space for coastal communities but also act as the first line of defense from coastal storms. As many of these unique coastal systems are affected by both oceanic and terrestrial processes, it is necessary to consider the holistic behavior of applicable terrestrial and coastal processes when investigating their evolution under plausible future scenarios for climate change, population growth and human activities. Such holistic assessments, also accounting for uncertainties, can readily be achieved via reduced-complexity modeling techniques, owing to their much faster simulation times compared to sophisticated process-based models. Here, we develop and demonstrate a novel probabilistic modeling framework to obtain stochastic projections of barrier-island evolution over the twenty-first century while accounting for relevant oceanic and terrestrial processes under climate change impacts and anthropogenic activities. The model is here demonstrated at the Chandeleur islands (Louisiana, United States) under the four Intergovernmental Panel on Climate Change (IPCC) greenhouse gas emission scenarios (i.e., Representative Concentration Pathways 2.6, 4.5, 6.0, and 8.5) with results indicating that there are significant uncertainties in projected end-century barrier-island migration distance and available barrier freeboard under the high emission scenario RCP 8.5. The range of uncertainties in these projections underscores the value of stochastic projections in supporting the development of effective adaptation strategies for these fragile coastal systems.

Published
2021
Full Text
View/download PDF

2. Understanding coastal morphodynamic patterns from depth-averaged sediment concentration

Author

Ribas, Francesca, Falques, Albert, De Swart, Huib E., Dodd, Nicholas, Garnier, Roland, Calvete, Daniel, Sub Physical Oceanography, Dep Natuurkunde, Marine and Atmospheric Research, Universitat Politècnica de Catalunya. Departament de Física, and Universitat Politècnica de Catalunya. DF - Dinàmica No Lineal de Fluids

Subjects
Sediment transport, Sand bars, BARRIER-ISLAND EVOLUTION, TRANSVERSE BARS, Platges -- Aspectes ambientals, Física [Àrees temàtiques de la UPC], MIDDLE ATLANTIC SHELF, SOUTHERN NORTH-SEA, SELF-ORGANIZATION, self-organization, CONNECTED SAND RIDGES, coastal morphodynamic patterns, sand ridges, INNER SHELF, beach cusps, BEACH CUSP FORMATION, sediment transport coastal morphodynamic patterns nearshore sand bars beach cusps sand ridges self-organization, PART 1, nearshore sandbars, MORPHOLOGICAL RESPONSE
Abstract

This review highlights the important role of the depth-averaged sediment concentration (DASC) to understand the formation of a number of coastal morphodynamic features that have an alongshore rhythmic pattern: beach cusps, surf zone transverse and crescentic bars, and shoreface-connected sand ridges. We present a formulation and methodology, based on the knowledge of the DASC (which equals the sediment load divided by the water depth), that has been successfully used to understand the characteristics of these features. These sand bodies, relevant for coastal engineering and other disciplines, are located in different parts of the coastal zone and are characterized by different spatial and temporal scales, but the same technique can be used to understand them. Since the sand bodies occur in the presence of depth-averaged currents, the sediment transport approximately equals a sediment load times the current. Moreover, it is assumed that waves essentially mobilize the sediment, and the current increases this mobilization and advects the sediment. In such conditions, knowing the spatial distribution of the DASC and the depth-averaged currents induced by the forcing (waves, wind, and pressure gradients) over the patterns allows inferring the convergence/divergence of sediment transport. Deposition (erosion) occurs where the current flows from areas of high to low (low to high) values of DASC. The formulation and methodology are especially useful to understand the positive feedback mechanisms between flow and morphology leading to the formation of those morphological features, but the physical mechanisms for their migration, their finite-amplitude behavior and their decay can also be explored.

Published
2015

3. Understanding coastal morphodynamic patterns from depth-averaged sediment concentration

Subjects
BARRIER-ISLAND EVOLUTION, TRANSVERSE BARS, MIDDLE ATLANTIC SHELF, SOUTHERN NORTH-SEA, SELF-ORGANIZATION, CONNECTED SAND RIDGES, sediment transport, coastal morphodynamic patterns, sand ridges, INNER SHELF, beach cusps, BEACH CUSP FORMATION, PART 1, nearshore sandbars, MORPHOLOGICAL RESPONSE
Abstract

This review highlights the important role of the depth-averaged sediment concentration (DASC) to understand the formation of a number of coastal morphodynamic features that have an alongshore rhythmic pattern: beach cusps, surf zone transverse and crescentic bars, and shoreface-connected sand ridges. We present a formulation and methodology, based on the knowledge of the DASC (which equals the sediment load divided by the water depth), that has been successfully used to understand the characteristics of these features. These sand bodies, relevant for coastal engineering and other disciplines, are located in different parts of the coastal zone and are characterized by different spatial and temporal scales, but the same technique can be used to understand them. Since the sand bodies occur in the presence of depth-averaged currents, the sediment transport approximately equals a sediment load times the current. Moreover, it is assumed that waves essentially mobilize the sediment, and the current increases this mobilization and advects the sediment. In such conditions, knowing the spatial distribution of the DASC and the depth-averaged currents induced by the forcing (waves, wind, and pressure gradients) over the patterns allows inferring the convergence/divergence of sediment transport. Deposition (erosion) occurs where the current flows from areas of high to low (low to high) values of DASC. The formulation and methodology are especially useful to understand the positive feedback mechanisms between flow and morphology leading to the formation of those morphological features, but the physical mechanisms for their migration, their finite-amplitude behavior and their decay can also be explored.

Published
2015

Catalog

Books, media, physical & digital resources
See catalog results