Coastal & Marine Geology Program > National Assessment of Coastal Change Hazards > Open File Report 03-337

An Overview of Coastal Land Loss: With Emphasis on the Southeastern United States

USGS Open File Report 03-337

by: Robert A. Morton

Summary Introduction Physical Agents of Land Loss: Waves, Currents, & Storm Surges Landslides & Cliff Retreat Sediment Budget Relative Sea Level Climate & Land Loss Role of Shoreline Characteristics: Composition, Induration, & Saturation Coastal Morphology & Vegetation Role of Human Activities: Introduction Transportation Coastal Construction River Modification Hydrocarbon & Groundwater Extraction Climate Alteration Coastal Excavation Wetland Losses Acknowledgments References

Summary In states bordering the Gulf of Mexico and the Atlantic Ocean, vast areas of coastal land have been destroyed since the mid 1800s as a result of natural processes and human activities. The physical factors that have the greatest influence on coastal land loss are reductions in sediment supply, relative sea level rise, and frequent storms, whereas the most important human activities are sediment excavation, river modification, and coastal construction. As a result of these agents and activities, coastal land loss is manifested most commonly as beach/bluff erosion and coastal submergence. Wetlands are a unique class of coastal lands so they are considered independent of upland coastal areas. Wetlands are subjected to the same physical process and activities as other coastal lands, but they are also susceptible to deterioration as a result of biogeochemical processes. Failed reclamation projects and induced subsidence also contribute locally to wetland losses in the southeastern US. continue to Introduction

Printable Version Related Research Projects: National Assessment of Coastal Change Hazards USGS Coastal & Marine Geology Program Coastal Classification Mapping Project USGS Coastal & Marine Geology Program West-Central Florida Coastal Studies Project USGS Coastal & Marine Geology Program Subsidence and Sea-Level Rise in Southeastern Louisiana: Implications for Coastal Management and Restoration USGS Coastal & Marine Geology Program Hurricane and Extreme Storm Impact Studies USGS Coastal & Marine Geology Program Related Links: Center for Coastal & Regional Marine Studies USGS

Coastal & Marine Geology Program > National Assessment of Coastal Change Hazards > Open File Report 03-337