Coastal Change During Hurricane Isabel 2003
Hurricane Isabel caused extensive erosion and overwash along the Outer Banks near Cape Hatteras, including the destruction of houses, the erosion of protective sand dunes, and the creation of island breaches. The storm eroded beaches and dunes in Frisco and Hatteras Village, southwest of the Cape. Overwash deposits covered roads and filled homes with sand. The most extensive beach changes were associated with the opening of a new breach about 500 m wide that divided into three separate channels that completely severed the island southwest of Cape Hatteras. The main breach, and a smaller one several kilometers to the south, occurred at minima in both island elevation and island width.
Read the report: USGS Fact Sheet 2009-3025
On September 18, 2003, Hurricane Isabel impacted the northern Outer Banks of North Carolina. At the Army's Field Research Facility in Duck, 125 km north of where the eyewall cut across Hatteras Island, the Category 2 storm generated record conditions, for twenty-seven years of monitoring 8.1 m significant wave height measured at a waverider buoy in 20 m of water and 1.5 m storm surge.
Coastal Change from Lidar
In a cooperative program between USGS and NASA, airborne lidar (NASA's EAARL - Experimental Advanced Airborne Research Lidar) was used to survey the beaches and dunes along a 350-km-long reach from Cape Henry (at the mouth of Chesapeake Bay) to Cape Lookout, North Carolina (see Index Map for survey area). With the accurate long-range forecast by NOAA's National Hurricane Center, we were able to acquire the pre-storm survey only two days before Isabel's landfall. A post-storm survey was flown three days following impact and allows detection of coastal change.
Oblique Aerial Photography
In addition to the lidar surveys, and from a different twin-engine plane, the Isabel impact zone was photographed and videotaped by the USGS, while another USGS crew inspected the observed changes from the ground.
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