Coastal Change Hazards: Hurricanes and Extreme Storms

Nor'Ida

RESEARCH HIGHLIGHTS Before and after photo comparisons: Maryland, Virginia, North Carolina

After making landfall on November 10, 2009 on Dauphin Island, Alabama, Tropical Storm Ida traveled to the northeast, eventually moving offshore into the Atlantic Ocean. The remnant low pressure associated with Ida collided with a high pressure located over the Northeast United States, creating a major nor'easter storm that battered the coastal midatlantic region for days. Waves exceeded 4.5 m at several NOAA buoys, and storm surge contributed to elevated water levels for several tidal cycles. Significant coastal changes, including dune erosion and overwash, were observed from the Outer Banks of North Carolina north to Long Island, New York.

The U.S. Geological Survey (USGS) Hurricanes and Extreme Storms Group is investigating coastal change that occurred along the sandy beaches of North Carolina, Virginia, Maryland, and Delaware as a result of the November 2009 nor'easter. Aerial video, still photography, and laser altimetry surveys of post-storm beach conditions will be collected for comparison with earlier data. The comparisons show the nature, magnitude, and spatial variability of coastal changes such as beach erosion, overwash deposition, and island breaching. These data will also be used to further refine predictive models of coastal impacts from severe storms.

Response Activities

Post-storm data collection (approx. 7-10 days)

• Post-storm airborne lidar topographic survey (collected 11/29/09)
• Oblique aerial photos of impacted coast (collected 12/04/09)

Post-storm coastal change analysis (approx. 4 weeks)

• Pre- and post-storm photo comparisons (web post 12/09)
• Post-storm oblique aerial photography (web post 03/26)
• Initial pre- and post-storm lidar 3D imagery of topography and coastal change (anticipated web post 2010)