Assessment of Wetland Area Change and Shoreline Erosion Due to Hurricane Sandy

Science Center Objects

Significant damage to coastal communities and surrounding wetlands of the north Atlantic states was caused by Hurricane Sandy in late October 2012, mostly tied to an associated storm surge of record extent and impact.

Figure 1. Example from previous investigations of wetland area change and shoreline erosion.
Figure 1. Example from previous investigations of wetland area change and shoreline erosion.

The Science Issue and Relevance: Significant damage to coastal communities and surrounding wetlands of the north Atlantic states was caused by Hurricane Sandy in late October 2012, mostly tied to an associated storm surge of record extent and impact. Documenting and understanding the occurrence of wetland loss and shoreline erosion from this storm event will provide for effective planning, mitigation, and restoration activities. Assessments of wetland change resulting from storm events have been made elsewhere in the past, consisting of analyses of multiple dates of satellite data to track landscape changes within the coastal zone, similar to the methodology utilized for coastal Louisiana detailed in USGS Scientific Investigations Map 3164 (http://pubs.usgs.gov/sim/3164/). An example of the results of this type of analysis is shown in Figure 1. The goal of this project is to quantify land area change over time to document and understand the short- and long-term effects of Hurricane Sandy on wetlands throughout the Atlantic coast of the United States.

Methodology for Addressing the Issue: The primary data source for this analysis consists of Landsat data -- Landsat 5 and 7 (1984-2012) and Landsat 8 (2013) imagery as it becomes available. The first step in the methodology consists of creating land/water classifications. Land/water classification will be conducted using a series of spectral bands and indices which are particularly sensitive to and indicative of the presence of water. Upon completion of the land/water classifications throughout the study area, both historical trends and changes following Hurricane Sandy will be examined. Change analysis will be conducted pre- and post-event, and areas of change will be identified. The study area consists of the coastal zone (defined by the federal water boundary and a 10-meter topographic contour) of the Atlantic Coast from approximately southern North Carolina to northern Maine.

Future Steps: The findings of this study will be compared to and help inform finer resolution analyses of coastal wetland change in the areas affected by Hurricane Sandy.

Location of the Study: The study area will consist of the coastal zone (defined by the federal water boundary and a 10-m topographic contour) of the Atlantic Coast from approximately southern North Carolina to northern Maine.