Large-scale coastal evolution of Louisiana's barrier islands

Jeffrey H. List; Bruce E. Jaffe; Sallenger

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USGS · 70016300

Large-scale coastal evolution of Louisiana's barrier islands

Jeffrey H. List·Bruce E. Jaffe·Sallenger

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Abstract

The prediction of large-scale coastal change is an extremely important, but distant goal. Here we describe some of our initial efforts in this direction, using historical bathymetric information along a 150 km reach of the rapidly evolving barrier island coast of Louisiana. Preliminary results suggest that the relative sea level rise rate, though extremely high in the area, has played a secondary role in coastal erosion over the last 100 years, with longshore transport of sand-sized sediment being the primary cause. Prediction of future conditions is hampered by a general lack of erosion processes understanding; however, an examination of the changing volumes of sand stored in a large ebb-tidal delta system suggests a continued high rate of shoreline retreat driven by the longshore re-distribution of sand.

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Source-reported bounding extent: 28.738763971370293° to 30.107117887092357° latitude; -93.4716796875° to -88.681640625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Jeffrey H. List, Bruce E. Jaffe, Sallenger. 1991. Large-scale coastal evolution of Louisiana's barrier islands. https://pubs.usgs.gov/publication/70016300

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