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St. Petersburg Coastal and Marine Science Center

National Assessment of Hurricane-Induced Coastal Erosion Hazards: Gulf of Mexico

Introduction

Sandy beaches provide a natural barrier between the ocean and inland communities, ecosystems, and resources. However, these dynamic environments move and change in response to winds, waves, and currents. During a hurricane, these changes can be large and sometimes catastrophic. High waves and storm surge act together to erode beaches and inundate low-lying lands, putting inland communities at risk. A decade of USGS research on storm-driven coastal change hazards has provided the data and modeling capabilities to identify areas of our coastline that are likely to experience extreme and potentially hazardous erosion during a hurricane.

The analysis is based on a storm-impact scaling model that uses observations of beach morphology combined with sophisticated hydrodynamic models to predict how the coast will respond to the direct landfall of category 1-5 hurricanes. Hurricane-induced water levels, due to both surge and waves, are compared to beach and dune elevations to determine the probabilities of three types of coastal change (1) collision dune toe is eroded by waves and surge, (2) overwash - sand is transported landward over the beach and dune by waves and surge, and (3) inundation - beach and dune are completely and continuously submerged by surge and wave setup. As new beach morphology observations and storm predictions become available, this analysis will be updated to describe how coastal vulnerability to storms will vary in the future.


Probabilities of Coastal Change
(click to use interactive map)

Key Findings

Percentage of Gulf of Mexico sandy beaches very likely (probability > 0.9) to experience erosion associated with collision, overwash, and inundation during category 1-5 hurricane landfall.
Hurricane Intensity Category
1 2 3 4 5
collision (dune erosion)
US Gulf of Mexico 99 100 100 100 100
Texas 99 100 100 100 100
Louisiana 100 99 100 100 100
Mississippi 100 100 100 100 100
Alabama 100 100 100 100 100
Florida Panhandle 98 99 100 100 100
Florida West Coast 99 100 100 100 100
overwash
US Gulf of Mexico 71 85 92 97 98
Texas 61 75 88 98 99
Louisiana 95 99 100 100 100
Mississippi 96 100 100 100 100
Alabama 69 99 100 100 100
Florida Panhandle 47 74 83 89 93
Florida West Coast 98 99 100 100 100
inundation
US Gulf of Mexico 27 58 73 83 89
Texas 20 54 62 73 85
Louisiana 62 86 95 100 100
Mississippi 35 93 100 100 100
Alabama 4 29 74 99 100
Florida Panhandle 5 25 51 69 77
Florida West Coast 42 91 99 99 99

Full Report

For more information, see USGS Open-File Report 2012-1084.

Download Data

ArcGIS Shapefiles:


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Page Last Modified: April 15, 2014 @ 01:01 PM (JSG)