U.S. Geological Survey 2017 1 tabular digital data data release DOI:10.5066/F78P5XNK Woods Hole Coastal and Marine Science Center, Woods Hole, MA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.5066/F78P5XNK https://www.sciencebase.gov/catalog/item/582ca4bce4b04d580bd37910 https://www.sciencebase.gov/catalog/file/get/582ca4bce4b04d580bd37910 E.A. Himmelstoss M.G. Kratzmann E.R. Thieler 2017 1 data release DOI:10.5066/F78P5XNK Reston, VA U.S. Geological Survey https://doi.org/10.5066/F78P5XNK https://www.sciencebase.gov/catalog/item/58055db4e4b0824b2d1c1ee2 Sandy ocean beaches are a popular recreational destination, often surrounded by communities containing valuable real estate. Development is on the rise despite the fact that coastal infrastructure is subjected to flooding and erosion. As a result, there is an increased demand for accurate information regarding past and present shoreline changes. To meet these national needs, the Coastal and Marine Geology Program of the U.S. Geological Survey (USGS) is compiling existing reliable historical shoreline data along open-ocean sandy shores of the conterminous United States and parts of Alaska and Hawaii under the National Assessment of Shoreline Change project. There is no widely accepted standard for analyzing shoreline change. Existing shoreline data measurements and rate calculation methods vary from study to study and prevent combining results into state-wide or regional assessments. The impetus behind the National Assessment project was to develop a standardized method of measuring changes in shoreline position that is consistent from coast to coast. The goal was to facilitate the process of periodically and systematically updating the results in an internally consistent manner. This table includes: measurement and positional errors associated with the 2001 lidar shoreline for Louisiana, a proxy-datum bias value that corrects for the unidirectional offset between the mean high water (MHW) elevation of the lidar and the high water line (HWL) shorelines, as well as a measurement uncertainty in the total water level. The dataset contains a common attribute with the M-values stored for the lidar data within the LA_shorelines.shp. These data are used in conjunction with the shoreline file to calculate rates of shoreline change for the U.S. Geological Survey's (USGS) National Assessment of Shoreline Change Project. Rates of long-term and short-term shoreline change were generated in a GIS using the Digital Shoreline Analysis System (DSAS) version 4.3. DSAS uses a measurement baseline method to calculate rate-of-change statistics. Transects are cast from the reference baseline to intersect each shoreline, establishing measurement points used to calculate shoreline change rates. Cross-referenced citations are applicable to the dataset as a whole. Additional citations are located within individual process steps that pertain specifically to the method described in that step. 2017 ground condition Complete None planned -90.953917 -88.819020 30.047229 29.043624 USGS Metadata Identifier USGS:582ca4bce4b04d580bd37910 None lidar uncertainty proxy-datum bias high water line offsets high water line uncertainty Shoreline Change Digital Shoreline Analysis System DSAS U.S. Geological Survey USGS Coastal and Marine Geology Program CMGP Woods Hole Coastal and Marine Science Center National Assessment of Shoreline Change Project National Oceanic and Atmospheric Administration NOAA Coastal Services Center CSC MHW Mean High Water HWL High Water Line Database IV format ISO 19115 Topic Category oceans environment geoscientificInformation Marine Realms Information Bank (MRIB) Keywords effects of coastal change coastal processes shoreline accretion shoreline erosion USGS Thesaurus coastal processes erosion shoreline accretion None Louisiana LA Chandeleur Islands Breton National Wildlife Refuge Breton Islands Pelican Island Lanaux Island Grand Terre Islands Grand Isle East Timbalier Island Isles Dernieres Gulf of Mexico United States North America None. Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset. U.S. Geological Survey E.A. Himmelstoss mailing and physical address

384 Woods Hole Road

Woods Hole MA 02543-1598 USA 508-548-8700 508-547-2310 ehimmelstoss@usgs.gov Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.2.2.3552 Robert A. Morton Tara L. Miller Laura J. Moore 2004 Open-File Report 2004-1043 Reston, VA U.S. Geological Survey https://pubs.usgs.gov/of/2004/1043/ E.R. Thieler E.A. Himmelstoss J.L. Zichichi A. Ergul 2009 Open-File Report 2008-1278 Reston, VA U.S. Geological Survey Current version of software at time of use was 4.3 https://woodshole.er.usgs.gov/project-pages/DSAS/version4/ https://woodshole.er.usgs.gov/project-pages/DSAS/ United States Geological Survey (USGS) National Aeronautics & Space Administration (NASA) Department of Commerce (DOC), National Oceanic & Atmospheric Administration (NOAA), National Ocean Service (NOS), Office for Coastal Management (OCM) 20141114 Charleston, SC NOAA's Ocean Service, Office for Coastal Management (OCM) Lidar data were obtained prior to the publication date listed in this citation. https://coast.noaa.gov/dataviewer/index.html?action=advsearch&qType=in&qFld=ID&qVal=525 ftp://coast.noaa.gov/pub/DigitalCoast/lidar1_z/geoid12a/data/525 https://coast.noaa.gov/dataviewer https://www.coast.noaa.gov Peter Ruggiero M.G. Kratzmann E.A. Himmelstoss E.R. Thieler David Reid 2013 Open-File Report 2012-1007 Reston, VA U.S. Geological Survey https://pubs.usgs.gov/of/2012/1007/ E.A. Himmelstoss M.G. Kratzmann E.R. Thieler 2017 Open-File Report 2017-1015 Reston, VA U.S. Geological Survey https://doi.org/10.3133/ofr20171015 The attributes in this table record positional and measurement uncertainties and datum offsets calculated during the process of extracting an operational mean high water shoreline from the lidar data as described in the process steps. The field names are based on the requirements for use within the Digital Shoreline Analysis System (DSAS) software (USGS Open-File Report 2008-1278). Each row contains data associated with an individual vertex point along the lidar shoreline in LA_shorelines.shp. The table only contains data where a mean high water shoreline point could be extrapolated from the lidar. The lidar shoreline has an average positional uncertainty of plus or minus 2.6 meters. An operational Mean High Water (MHW) shoreline was extracted from the lidar surveys within MATLAB v7.6 using a method similar to the one developed by Stockdon et al. (2002). Shorelines were extracted from cross-shore profiles which consist of bands of lidar data 2 m wide in the alongshore direction and spaced every 20 m along the coast. For each profile, the seaward sloping foreshore points were identified and a linear regression was fit through them. The regression was evaluated at the operational MHW elevation to yield the cross-shore position of the MHW shoreline. If the MHW elevation was obscured by water points, or if a data gap was present at MHW, the linear regression was simply extrapolated to the operational MHW elevation. A lidar positional uncertainty associated with this point was also computed. The horizontal offset between the datum-based lidar MHW shoreline and the proxy-based historical shorelines nearly always acts in one direction and the "bias" value was computed at each profile (Ruggiero and List, 2009). In addition an uncertainty associated with the bias was also computed, which can also be thought of as the uncertainty of the HWL shorelines due to water level fluctuations. Repeating this procedure at successive profiles generated a series of X,Y points that contain a lidar positional uncertainty, a bias, and a bias uncertainty value. Ruggiero, P. and List, J.H., 2009. Improving Accuracy and Statistical Reliability of Shoreline Position and Change Rate Estimates. Journal of Coastal Research: v.25, n.5, pp.1069-1081. Stockdon, H.F., Sallenger, A.H., List, J.H., and Holman, R.A., 2002. Estimation of Shoreline Position and Change using Airborne Topographic Lidar Data: Journal of Coastal Research, v.18, n.3, pp.502-513. 20080812 Amy Farris U.S. Geological Survey mailing and physical address

384 Woods Hole Road

Woods Hole MA 02543-1598 USA 508-548-8700 508-457-2310 afarris@usgs.gov The series of operational MHW points extracted from the cross-shore lidar profiles were converted to a .dbf file storing the lidar positional uncertainty, the bias correction value, and the uncertainty of the bias correction for each point of the original lidar data. During the rate calculation process DSAS uses linear referencing to retrieve the uncertainty and bias values stored in the associated table. For a detailed explanation of the method used to store bias and uncertainty data in a table, please refer to Appendix 2, section 12.3 in the DSAS user guide: Himmelstoss, E.A. 2009. "DSAS 4.0 Installation Instructions and User Guide" in: Thieler, E.R., Himmelstoss, E.A., Zichichi, J.L., and Ergul, Ayhan. 2009. Digital Shoreline Analysis System (DSAS) version 4.0 - An ArcGIS extension for calculating shoreline change: U.S. Geological Survey Open-File Report 2008-1278. https://woodshole.er.usgs.gov/project-pages/DSAS/version4/images/pdf/DSASv4_3.pdf 20100602 E.A. Himmelstoss U.S. Geological Survey mailing and physical address

384 Woods Hole Road

Woods Hole MA 02543-1598 USA 508-548-8700 x2262 508-457-2310 ehimmelstoss@usgs.gov The shoreline uncertainty table (.dbf) was imported into a personal geodatabase in ArcCatalog v10.2 by right-clicking on the geodatabase > Import > Table (single). The uncertainty table was used with the Digital Shoreline Analysis System (DSAS) v4.3 software to perform rate calculations. This process step and the subsequent process step was performed by the same person - M.G. Kratzmann. 20150825 M.G. Kratzmann U.S. Geological Survey mailing address

384 Woods Hole Road

Woods Hole MA 02543 USA 508-548-8700 508-457-2310 mkratzmann@usgs.gov The shoreline uncertainty table was exported from the personal geodatabase back to a stand-alone dBase file using ArcCatalog v10.2 by right-clicking on the database file > Export > To dBase file (single) for publication purposes. 20150827 Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. 20170825 U.S. Geological Survey Alan O. Allwardt Contractor -- Information Specialist mailing and physical address

2885 Mission Street

Santa Cruz CA 95060 831-460-7551 831-427-4748 aallwardt@usgs.gov Added keywords section with USGS persistent identifier as theme keyword. Process performed on 20200810. The metadata title was modified to move the location name to the beginning of the title to account for the alphabetical listing of the individual records when ScienceBase migrates the data release to a new platform and "flattens" the data release structure (20260302). 20260302 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543-1598 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov LA_shorelines_uncertainty uncertainty table U.S. Geological Survey OID Internal feature number. Esri Sequential unique whole numbers that are automatically generated. ID This field is case-sensitive and name specific. The field contains a cross-shore lidar profile ID stored as the M-value (measure value) at each vertex in the calibrated shoreline route. This serves as the link between the lidar shoreline and the uncertainty table and must be a unique number at each point. U.S. Geological Survey 291 436900 UNCY This field heading is case-sensitive and name specific. The field contains the plus/minus horizontal uncertainty (meters) in the lidar shoreline position at each cross-shore beach profile. For details on the components that make up this uncertainty, refer to the Methods section of USGS Open-File report 2012-1007 cross-referenced in the metadata. U.S. Geological Survey 0 16.53 meters BIAS This field heading is case-sensitive and name specific. The field contains a proxy-datum bias value describing the unidirectional horizontal offset (in meters) between the MHW elevation of the lidar data and HWL shoreline positions. U.S. Geological Survey 0 8.66 meters UNCYB This field heading is case-sensitive and name specific. The field contains the uncertainty in the calculated proxy-datum bias value (BIAS) in meters. U.S. Geological Survey 0 4.035 meters The entity and attribute information provided here describes the tabular data associated with the dataset. Please review the individual attribute descriptions for detailed information. U.S. Geological Survey U.S. Geological Survey mailing and physical address

Denver Federal Center

Building 810

MS 302

Denver CO 80225 USA 1-888-275-8747 sciencebase@usgs.gov Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. dBase IV .dbf file format storing structured attribute data This dBase file contains lidar positional and measurement uncertainties, proxy-datum bias offset values, and total water level uncertainties used when calculating rates in the Digital Shoreline Analysis System (DSAS) software with associated metadata. no compression applied 0.415 https://www.sciencebase.gov/catalog/file/get/582ca4bce4b04d580bd37910 https://www.sciencebase.gov/catalog/item/582ca4bce4b04d580bd37910 https://www.sciencebase.gov/catalog/item/58055db4e4b0824b2d1c1ee2 https://doi.org/10.5066/F78P5XNK The first link downloads the contents of the data page as a zip file, the second link is to the landing page of the data, the third and fourth links are to the main landing page of the data release. None These data are available in dBase file format. The user must have software capable of reading or importing the dBase formatted data file. 20260302 E.A. Himmelstoss U.S. Geological Survey mailing address

384 Woods Hole Road

Woods Hole MA 02543-1598 USA 508-548-8700 x2262 508-457-2310 whsc_data_contact@usgs.gov The metadata contact email address is a generic address in the event the person is no longer with USGS. (updated on 20240319) FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time