Coastal Impacts of the 2004 Hurricanes Measured with Airborne Lidar: Initial Results

摘要

The impact zones of the four hurricanes that came ashore in the United States in 2004 were surveyed with airborne LIDAR both before and after landfall in a cooperative effort between the U.S. Geological Survey (USGS), the National Aeronautics and Space Administration (NASA), and U.S. Army Corps of Engineers (USACE). The surveys were compared to quantify change and showed that coastal response was unique for each storm. For example, the swath of hurricane-force winds in Hurricane Charley was narrow and major coastal-change impacts were limited to several tens of kilometers of shoreline near landfall on the southwest coast of Florida, where a 0.5-kilo-meter-wide breach opened through North Captiva Island. In contrast, Hurricane Frances was a larger, weaker storm that caused moderate coastal erosion extending for ～100 kilometers along the Florida south-central east coast. However, the most important role of Frances may have been making the coast more vulnerable to erosion from Hurricane Jeanne, which followed the same track several weeks later. The most extensive coastal change occurred during Hurricane Ivan on the Alabama and Florida Panhandle coasts. In Gulf Shores, AL, where the storm's strongest winds made landfall, the barrier islands were completely inundated by storm surge. The sea-level gradient between Gulf and back bays drove a strong landward current that transported massive amounts of sand across the island.