USGS - science for a changing world

St. Petersburg Coastal and Marine Science Center

St. Petersburg Coastal and Marine Science Center > Alabama Barrier Island Restoration Study > Research > Hydrodynamic and Morphological Change Modeling

Alabama Barrier Island Restoration Study

Research - Hydrodynamic and Morphological Change Modeling

The development of a numerical modeling framework that can simulate the evolution of Dauphin Island is needed to support evaluation of restoration alternatives. Prior to the start of this project, there was no established or scientifically-validated model framework available that was suitable and robust for predicting the evolution of a barrier island on the time-scale of decades, including the impacts of storms and longer-term processes, and considering both restoration and no-action scenarios. The model framework will include a series of components to capture the dominant processes that dictate how the island evolves, including:

The model framework will be calibrated/validated by hindcasting the island evolution between 1998 and 2013 and comparing to the 15 lidar surveys collected during that time period. Model simulations will provide a quantitative understanding of the processes governing the past and present Dauphin Island barrier system. Restoration alternatives will then be incorporated into the present day island configuration and simulations using the same model framework will be performed to estimate the island response in the future over various time periods.

Hydrodynamic and morphologic output from this model framework will be passed to other contributors of the project to inform the modeling of water quality, structural response, and habitat parameters, all of which change as the island morphology evolves.

d
Domains for the individual models coupled in the hydrodynamic/morphodynamic simulation framework.
Domains for the individual models coupled in the hydrodynamic/morphodynamic simulation framework. Black points represent the outer northern Gulf of Mexico wave model domain, red points are the inner wave, circulation, and sediment transport model domain, and the depth colormap indicates the nested beach and dune storm response model.
    post-Ivan elevations using the Xbeach storm model
Observed (top left) and modeled (middle left) post-Ivan elevations using the Xbeach storm model. Specific comparisons of the simulated and observed elevation of the dune base (top-right) and crest (middle-right) are also shown. Detailed view of the simulated post-storm shoreline is overlaid on the observed post-Ivan center island section (bottom). Colormaps correspond to elevations. Data is provisional.

(Top) Island segments used in the calculation of dune recovery rates following Hurricane Katrina. (Bottom) Observed and modeled dune growth rates at a single cross-shore transect.
Island segments used in the calculation of dune recovery rates following Hurricane Katrina (top). Observed and modeled dune growth rates at a single cross-shore transect (bottom). Data is provisional.

These data are preliminary or provisional and are subject to revision. They are being provided to meet the need for timely best science. The data have not received final approval by the U.S. Geological Survey (USGS) and are provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the data.

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://coastal.er.usgs.gov/alabama-barrier-island-restoration-study/research/modeling.html
Page Contact Information: Feedback
Page Last Modified: September 20, 2017 @ 01:50 PM (JSG)