Project Description

The U.S. Geological Survey (USGS) National Assessment of Coastal Change Hazards project strives to provide hazard information to Federal, State, and local government agencies; emergency-response officials; resource managers; and residents. As part of the National Assessment project, commercial vendors were contracted by the USGS to conduct airborne lidar topographic surveys to document beach and dune morphology post-Hurricane Sandy, which made landfall as an extratropical cyclone on October 29, 2012 near Atlantic City, New Jersey.

Woolpert, Inc. conducted a lidar survey of Fire Island, New York on November 5, 2012, while Photo Science, Inc. conducted lidar surveys from Cape Henlopen, Delaware to Cape Lookout, North Carolina on November 5, 8, 9, 10, 11, 12, 16, 26, 28, and 29, 2012. Initial processing of point-cloud data and creation of Digital Elevation Models (DEMs) were performed by the contractor. USGS processing included gridding of the three-dimensional lidar data using a fixed-scale interpolator (Plant and others, 2002), which allows for variability in resolution-2.5 meters (m) cross-shore and 10 m alongshore. Shoreline, dune crest, and dune toe position were extracted from cross-shore profiles of gridded data at a regular alongshore interval of 10m. Detailed description of the methodologies for extracting shorelines and dunes from lidar topography can be found in Stockdon and others (2012) and references contained therein. Post-storm coastal morphology is used to document coastal change resulting from the storm; define vulnerability to erosion during future storms, given current beach conditions; and assist in the decision-making for recovery and rebuilding efforts.

For more information about the USGS National Assessment of Coastal Change Hazards project's research on hurricanes and extreme storms, please visit the National Assessment of Coastal Change Hazards Website.

Selected References

Plant, N.G., Holland, K.T., and Puleo, J.A., 2002, Analysis of the scale of errors in nearshore bathymetric data: Marine Geology, v. 191, no. 1-2, p. 71-86.

Stockdon, H.F., Doran, K.S., and Sallenger, A.H., 2009, Extraction of lidar-based dune-crest elevations for use in examining the vulnerability of beaches to inundation during hurricanes: Journal of Coastal Research, v. 25, no. 6, p. 59-65.

Stockdon, H.F., Doran, K.J., Thompson, D.M., Sopkin, K.L., Plant, N.G., and Sallenger, A.H., 2012, National assessment of hurricane-induced coastal erosion hazards—Gulf of Mexico: U.S. Geological Survey Open-File Report 2012–1084, 51 p. (Also available at https://pubs.usgs.gov/of/2012/1084/.)

Weber, K.M., List, J.H., and Morgan, K.L.M., 2005, An operational mean high water datum for determination of shoreline position from topographic lidar data: U.S. Geological Survey Open-File Report 2005-1027. (Also available at https://pubs.usgs.gov/of/2005/1027/.)