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Karen Morgan

Publications and source records attributed to Karen Morgan.

5 recordsLinked to original sources
USGS2009

Hurricane Rita and the destruction of Holly Beach, Louisiana: Why the chenier plain is vulnerable to storms

Hurricane Rita devastated gulf-front communities along the western Louisiana coast in 2005. LIDAR (light detection and ranging) topographic surveys and aerial photography collected before and after the storm showed the loss of every structure within the community of Holly Beach. Average shoreline change along western Louisiana's 140-km-long impacted shore was −23.3 ± 30.1 m of erosion, although shoreline change in Holly Beach was substantially less, and erosion was not pervasive where the structures were lost. Before the storm, peak elevations of the dunes, or berms in the absence of dunes, along the impacted shore averaged 1.6 m. The storm surge, which reached 3.5 m just east of Holly Beach, completely inundated the beach systems along the impacted western Louisiana shore. The high surge potential and low land elevations make this coast extremely vulnerable to hurricanes. In fact, most of the western Louisiana shore impacted by Rita will be completely inundated by the storm surge of a worst-case Saffir-Simpson category 1 hurricane. All of this shore will be inundated by worst-case category 2–5 storms.

Louisiana↗
USGS2009

Coastal change during Hurricane Isabel 2003

On September 18, 2003, Hurricane Isabel made landfall on the northern Outer Banks of North Carolina. At the U.S. Army Corps of Engineer'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 the 27 years of monitoring. The storm produced an 8.1 m high wave measured at a waverider buoy in 20 m of water and a 1.5 m storm surge. As part of a program to document and better understand the changes in vulnerability of the Nation's coasts to extreme storms, the U.S. Geological Survey (USGS), in collaboration with the National Aeronautics and Space Administration (NASA), surveyed the impact zone of Hurricane Isabel. Methods included pre- and post-storm photography, videography, and lidar. 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 (not shown), occurred at minima in both island elevation and island width.

North Carolina↗
USGS2009

Coastal change during Hurricane Dennis 2005

Hurricane Dennis made landfall as a Category 3 storm on Santa Rosa Island in the Florida Panhandle on July 10, 2005. Exposed to some of the strongest winds, Santa Rosa Island suffered erosion, as well as severe overwash. A storm surge of 2 m was recorded near Navarre Beach. The U.S. Geological Survey (USGS) and U.S. Army Corps of Engineers (USACE) are collaborating in a research project investigating coastal change that occurred as a result of Hurricane Dennis. The USGS acquired still oblique aerial photography both before and after hurricane landfall to better understand the impacts of extreme storms on coastal environments. On Tuesday, July 12, 2005, scientists conducted an aerial photographic survey of Santa Rosa Island, Florida, that was impacted by Hurricane Dennis. The photographs were compared to pre-Dennis photographs taken in July 2001 and after the landfall of Hurricane Ivan in September 2004 to illustrate extreme coastal change. On Santa Rosa Island, the storm eroded dunes and beaches, and overwashed roads. In Navarre Beach, parking lots and roads were covered with sand and dune walkovers damaged or destroyed.

Florida↗
USGS2004

Report of the U.S. Geological Survey Lidar Workshop sponsored by the Land Remote Sensing Program and held in St. Petersburg, FL, November 2002

The first United States Geological Survey (USGS) Light Detection And Ranging (lidar) Workshop was held November 20-22, 2002 in St. Petersburg, Florida to bring together scientists and managers from across the agency. The workshop agenda focused on six themes: 1) current and future lidar technologies, 2) lidar applications within USGS science and disciplines, 3) calibration and accuracy assessment, 4) tools for processing and evaluating lidar data sets, 5) lidar data management, and 6) commercial and contracting issues. These six themes served as the topics for workshop plenary sessions as well as the general focus for associated breakout sessions. A number of recommendations are presented regarding the role the USGS should play in the future application and development of lidar technology.

Open-File Report↗