The U.S. Geological Survey (USGS), in cooperation with the Coastal Research Laboratory in the Department of Geology and Geophysics at the University of New Orleans (UNO) and the Center for Coastal Energy and Environmental Resources at Louisiana State University (LSU), is investigating the processes of coastal erosion and wetland loss in Louisiana (Sallenger and others, 1987; Sallenger and Williams 1989; Penland and others, 1992). Building on the USGS Louisiana Barrier Island Study (Williams and others, 1992) and the USGS Hurricane Andrew impact assessment (Penland and others, 1998), this data layer depicts the shoreline as it stood in 1887. The Isles Dernieres are located about 120 km southwest of New Orleans. This barrier island shoreline is 32 km long and extends from Caillou Bayou east to Wine Island Pass. The Isles Dernieres represent a barrier island arc developed from the reworking and erosion of an abandoned distributary of the Lafourche delta complex within the Mississippi River delta plain (Penland and others, 1988). Previous work by McBride and others (1992) documented a long-term (1887-1988) gulfside erosion rate of -11.1 m/y and a short-term (1978-1988) gulfside erosion rate of -19.2 m/y. The long-term bayside (1906- 1988) erosion rate was measured at -0.6 m/y and the short-term (1978-1988) bayside erosion rate was measured at -5.2 m/y. The Isles Dernieres decreased in area at a rate of -28.2 ha/y between 1887 and 1988, suggesting the long-term date of disappearance would be 2015. The rate of area loss between 1978 and 1988 was measured at -42.7 ha/y suggesting a short-term disappearance date of 2004. In the 1992 Hurricane Andrew impact assessment by Penland and others (1998), the Isles Dernieres experienced a brief and intense period of increased erosion. The average gulfside erosion rate accelerated to -59.37 m/y and the average bayside erosion rate accelerated to -10.8 m/y during the year of the 1992 Hurricane Andrew impact. The Isles Dernieres rate of area change accelerated to -155.7 ha/y during the 1992 hurricane season. Hurricane Andrew accelerated the long-term area loss rate to -28.5 ha/y and the shortterm area loss rate to -49.54 ha/y. The Hurricane Andrew impact on the Isles Dernieres produced 3-5 years of erosion in a matter of days. After the Hurricane Andrew impact, the projected long-term disappearance date of the Isles Dernieres was reduced from 2015 to 2012 and the short term disappearance date was reduced from 2004 to 2003. In this shoreline change update, the authors used the methods and transects used by McBride and others (1992) to insure data compatibility of the new measurements and analysis.

The U.S. Geological Survey (USGS), in cooperation with the Coastal Research Laboratory in the Department of Geology and Geophysics at the University of New Orleans (UNO) and the Center for Coastal Energy and Environmental Resources at Louisiana State University (LSU), is investigating the processes of coastal erosion and wetland loss in Louisiana (Sallenger and others, 1987; Sallenger and Williams 1989; Penland and others, 1992). Building on the USGS Louisiana Barrier Island Study (Williams and others, 1992), this data layer depicts the South Chandeleur Island as is stood in 1999. In order to quantify shoreline changes since 1989, new vertical aerial mapping photography was acquired in 1999. The methods and transects used by McBride and others (1992) were used to insure data compatibility of the new measurements and analysis .

The U.S. Geological Survey (USGS), in cooperation with the Coastal Research Laboratory in the Department of Geology and Geophysics at the University of New Orleans (UNO) and the Center for Coastal Energy and Environmental Resources at Louisiana State University (LSU), is investigating the processes of coastal erosion and wetland loss in Louisiana (Sallenger and others, 1987; Sallenger and Williams 1989; Penland and others, 1992). Building on the USGS Louisiana Barrier Island Study (Williams and others, 1992), this data layer depicts the shoreline as it stood in 1996, which provides an 8.9 year update of McBride and others (1992). The Timbalier Islands are located about 100 km south-southwest of New Orleans. This barrier island shoreline is 30 km long and extends east from Cat Island Pass to Raccoon Pass. The Timbalier Islands represent a flanking barrier island system developed from the reworking and erosion of an abandoned distributary of the Lafourche delta complex within the Mississippi River delta plain (Penland and others, 1988). Island evolution is driven by predominant longshore sediment transport and storm overwash, causing the island arc to migrate to the north and west. The present configuration of the Timbalier Islands consists of Timbalier Island to the west, Timbalier Shoal, and East Timbalier Island to the east. Timbalier Shoal, located between the two islands within Little Pass Timbalier, is a transient area of moving sand, which is subaerial for some periods of measurement. The Gulf shoreline of East Timbalier Island has been armored by a rock seawall with a second seawall constructed landward in an attempt to protect oil and gas facilities on the bayside. In order to quantify shoreline changes since January 21, 1988, new vertical aerial mapping photography was acquired on December 9, 1996 The methods and transects used by McBride and others (1992) were used to insure data compatibility of the new measurements and analysis

The U.S. Geological Survey (USGS), in cooperation with the Coastal Research Laboratory in the Department of Geology and Geophysics at the University of New Orleans (UNO) and the Center for Coastal Energy and Environmental Resources at Louisiana State University (LSU), is investigating the processes of coastal erosion in Louisiana (Sallenger and others, 1987; Sallenger and Williams 1989; Penland and others, 1992). Building on the USGS Louisiana Barrier Island Study (Williams and others, 1992), this data layer depicts the Caminada-Moreau shoreline as it stood in 1996. In order to quantify shoreline changes since January 21, 1988, new vertical aerial mapping photography was acquired on December 9, 1996. The methods and transects used by McBride and others (1992) were used to insure data compatibility of the new measurements and analysis.

The U.S. Geological Survey (USGS), in cooperation with the Coastal Research Laboratory in the Department of Geology and Geophysics at the University of New Orleans (UNO) and the Center for Coastal Energy and Environmental Resources at Louisiana State University (LSU), is investigating the processes of coastal erosion and wetland loss in Louisiana (Sallenger and others, 1987; Sallenger and Williams 1989; Penland and others, 1992). Building on the USGS Louisiana Barrier Island Study (Williams and others, 1992), this data layer depicts the North Chandeleur Island as is stood in 1855. In order to quantify shoreline changes since 1989, new vertical aerial mapping photography was acquired on December 9, 1996. The methods and transects used by McBride and others (1992) were used to insure data compatibility of the new measurements and analysis .

The U.S. Geological Survey (USGS), in cooperation with the Coastal Research Laboratory in the Department of Geology and Geophysics at the University of New Orleans (UNO) and the Center for Coastal Energy and Environmental Resources at Louisiana State University (LSU), is investigating the processes of coastal erosion and wetland loss in Louisiana (Sallenger and others, 1987; Sallenger and Williams 1989; Penland and others, 1992). Building on the USGS Louisiana Barrier Island Study (Williams and others, 1992), this data layer depicts the North Chandeleur Island as is stood in 1999. In order to quantify shoreline changes since 1989, new vertical aerial mapping photography was acquired in 1999. The methods and transects used by McBride and others (1992) were used to insure data compatibility of the new measurements and analysis .

The U.S. Geological Survey (USGS), in cooperation with the Coastal Research Laboratory in the Department of Geology and Geophysics at the University of New Orleans (UNO) and the Center for Coastal Energy and Environmental Resources at Louisiana State University (LSU), is investigating the processes of coastal erosion and wetland loss in Louisiana (Sallenger and others, 1987; Sallenger and Williams 1989; Penland and others, 1992). Building on the USGS Louisiana Barrier Island Study (Williams and others, 1992), this data layer depicts the shoreline as it stood in 1887. The Timbalier Islands are located about 100 km south-southwest of New Orleans. This barrier island shoreline is 30 km long and extends east from Cat Island Pass to Raccoon Pass. The Timbalier Islands represent a flanking barrier island system developed from the reworking and erosion of an abandoned distributary of the Lafourche delta complex within the Mississippi River delta plain (Penland and others, 1988). Island evolution is driven by predominant longshore sediment transport and storm overwash, causing the island arc to migrate to the north and west. The present configuration of the Timbalier Islands consists of Timbalier Island to the west, Timbalier Shoal, and East Timbalier Island to the east. Timbalier Shoal, located between the two islands within Little Pass Timbalier, is a transient area of moving sand, which is subaerial for some periods of measurement. The Gulf shoreline of East Timbalier Island has been armored by a rock seawall with a second seawall constructed landward in an attempt to protect oil and gas facilities on the bayside. In order to quantify shoreline changes since January 21, 1988, new vertical aerial mapping photography was acquired on December 9, 1996 The methods and transects used by McBride and others (1992) were used to insure data compatibility of the new measurements and analysis

The Storm-Induced Coastal Change Hazards component of the National Assessment of Coastal Change Hazards project focuses on understanding the magnitude and variability of extreme storm impacts on sandy beaches. Lidar-derived beach morphologic features such as dune crest, toe and shoreline help define the vulnerability of the beach to storm impacts. This dataset defines the elevation and position of the seaward-most dune crest and toe and the mean high water shoreline derived from the 2007 Northeast Barrier Islands (New Jersey and New York) USGS Experimental Advanced Airborne Research Lidar (EAARL) lidar survey. Beach width is included and is defined as the distance between the dune toe and shoreline along a cross-shore profile. The beach slope is calculated using this beach width and the elevation of the shoreline and dune toe.

As part of the Barrier Island Evolution Research (BIER) project, scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center (SPCMSC) collected sediment samples from the northern Chandeleur Islands in July 2013. The overall objective of this project, which integrates geophysical (bathymetric, seismic, and topographic) and sedimentologic data, is to better understand the depositional and erosional processes that drive the morphologic evolution of barrier islands over annual to interannual timescales (1 to 5 years). Between June 2010 and April 2011, in response to the Deepwater Horizon oil spill, the State of Louisiana constructed a sand berm extending more than 14 kilometers (km) along the northern Chandeleur Islands platform. The construction of the berm provided a unique opportunity to investigate how this new sediment source will interact with and affect the morphologic evolution of the barrier-island system. Data collected from this study will be used to describe differences in the physical characteristics and spatial distribution of sediments both along the axis of the berm and also along transects across the berm and onto the adjacent barrier island. Comparison of these data with data from prior sampling efforts will provide information about sediment interactions and movement between the berm and the natural island platform, improving our understanding of short-term morphologic change and processes in this barrier-island system. This data series serves as an archive of sediment data collected in July 2013 from the Chandeleur Islands sand berm and adjacent barrier-island environments. Data products, including descriptive core logs, core photographs and x-radiographs, results of sediment grain-size analyses, sample location maps, and Geographic Information System (GIS) data files with accompanying formal Federal Geographic Data Committee (FDGC) metadata, can be downloaded from https://pubs.usgs.gov/ds/894/ds894_data.html.

The Storm-Induced Coastal Change Hazards component of the National Assessment of Coastal Change Hazards project focuses on understanding the magnitude and variability of extreme storm impacts on sandy beaches. Lidar-derived beach morphologic features such as dune crest, toe and shoreline help define the vulnerability of the beach to storm impacts. This dataset defines the elevation and position of the seaward-most dune crest and toe and the mean high water shoreline derived from the 2005 Experimental Advanced Airborne Research Lidar (EAARL) Post-Dennis (Texas) lidar survey. Beach width is included and is defined as the distance between the dune toe and shoreline along a cross-shore profile. The beach slope is calculated using this beach width and the elevation of the shoreline and dune toe.