Metadata: Identification_Information: Citation: Citation_Information: Originator: Meredith G. Kratzmann Originator: Amy S. Farris Publication_Date: 20260622 Title: Alabama: shorelines (1849-2022) used to calculate shoreline change rates Edition: 1.0 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1JE2KSO Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program Online_Linkage: https://doi.org/10.5066/P1JE2KSO Online_Linkage: https://www.sciencebase.gov/catalog/item/69e2b013b66b0195694c11e7 Larger_Work_Citation: Citation_Information: Originator: Meredith G. Kratzmann Originator: Amy S. Farris Originator: Kathryn M. Weber Publication_Date: 2026 Title: National Shoreline Change—A GIS compilation of vector shorelines and associated shoreline change data from the 1800s to the 2020s for the coast of Alabama Edition: 1.0 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1JE2KSO Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: suggested citation: Kratzmann, M.G., Farris, A.S., and Weber, K.M., 2026, National Shoreline Change—A GIS compilation of vector shorelines and associated shoreline change data from the 1800s to the 2020s for the coast of Alabama: U.S. Geological Survey data release, https://doi.org/10.5066/P1JE2KSO. Online_Linkage: https://doi.org/10.5066/P1JE2KSO Online_Linkage: https://www.sciencebase.gov/catalog/item/69e2a7d5b66b0195694c1197 Description: Abstract: The U.S. Geological Survey (USGS) maintains shoreline positions for the United States coasts from various historical sources, such as aerial photographs or topographic surveys, and contemporary sources, such as lidar-point clouds and digital elevation models. Shorelines are compiled in a Geographic Information System (GIS) and analyzed in the USGS Digital Shoreline Analysis System (DSAS) software to calculate rates of change. Keeping a record of historical shoreline positions is an effective method to monitor change over time, enabling scientists to identify areas most susceptible to erosion or accretion. These data can help coastal managers understand which areas of the coast are vulnerable to change. The shoreline positions and shoreline change rates provide actionable information to homeowners, coastal communities, and managers of public and private properties to improve resiliency for coastal hazards. Purpose: Shoreline positions compiled from existing and new sources are included in this dataset for Alabama from the 1800s to the 2020s. Alabama shorelines span 173 years ranging from 1849 to 2022 and were extracted from topographic survey sheets (T-sheets), aerial photographs, and lidar data. Source agencies include: USGS, National Oceanic and Atmospheric Administration (NOAA), U.S. Army Corps of Engineers (USACE), Mississippi Department of Environmental Quality, Office of Geology (MOG), University of South Alabama (USA), Florida Department of Environmental Protection (FLDEP), United States Department of Agriculture - Farm Service Agency Aerial Photography Field Office (USDA FSA APFO), Geological Survey of Alabama - Acquired from University of Alabama's Cartographic Research Laboratory (GSA/UA), USGS Earth Resources Observation and Science Center (USGS EROS), National Aeronautics and Space Administration (NASA), and National Park Service (NPS). In this release, nine new tidal datum-based mean high water (MHW) shorelines extracted from 1998, 2005, 2007, 2010, 2015, 2016, 2018, 2020, and 2022 lidar elevation data were used in the analysis (coverage not necessarily continuous statewide). Historical shoreline positions serve as easily understood features that can be used to describe the movement of beaches through time. Long-term (LT) century-scale and short-term (ST) decadal-scale shoreline change rates were generated using the Digital Shoreline Analysis System (DSAS) version 6.1. 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. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1849 Ending_Date: 2022 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -88.345344 East_Bounding_Coordinate: -87.518313 North_Bounding_Coordinate: 30.285429 South_Bounding_Coordinate: 30.219182 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: oceans Theme_Keyword: environment Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Shoreline Theme_Keyword: Shoreline change Theme_Keyword: Digital Shoreline Analysis System Theme_Keyword: DSAS Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: Woods Hole Coastal and Marine Science Center Theme_Keyword: WHCMSC Theme_Keyword: Mean High Water Theme_Keyword: MHW Theme_Keyword: High Water Line Theme_Keyword: HWL Theme_Keyword: Wet-Dry Line Theme_Keyword: WDL Theme_Keyword: Topographic Survey Sheet Theme_Keyword: T-sheet Theme: Theme_Keyword_Thesaurus: USGS thesaurus Theme_Keyword: geospatial datasets Theme_Keyword: coastal processes Theme_Keyword: aerial photography Theme_Keyword: lidar Theme_Keyword: digital elevation models Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:69e2b013b66b0195694c11e7 Place: Place_Keyword_Thesaurus: GNIS Place_Keyword: State of Alabama Place_Keyword: Dauphin Island Place_Keyword: Fort Morgan Alabama Place_Keyword: Gulf Shores Place: Place_Keyword_Thesaurus: None Place_Keyword: Gulf Coast Place_Keyword: Bon Secour National Wildlife Refuge Place_Keyword: United States of America Place_Keyword: North America Access_Constraints: No access constraints. Please see 'Distribution Information' for details. Use_Constraints: These data are marked with a Creative Commons CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. 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. These data are not to be used for navigation. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Meredith G. Kratzmann Contact_Address: Address_Type: mailing and physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: mkratzmann@contractor.usgs.gov Browse_Graphic: Browse_Graphic_File_Name: https://www.sciencebase.gov/catalog/file/get/69e2b013b66b0195694c11e7?name=AL_shorelines.png&allowOpen=true Browse_Graphic_File_Description: Map view of data. Blue lines indicate the extent of the shoreline data in Alabama. Browse_Graphic_File_Type: PNG Native_Data_Set_Environment: Microsoft Windows 11 Enterprise; Esri ArcGIS Pro 3.5.5 Cross_Reference: Citation_Information: Originator: Rachel E. Henderson Originator: Amy S. Farris Originator: Meredith G. Kratzmann Originator: Marie K. Bartlett Originator: Ayhan Ergul Originator: John McAndrews Originator: Raison Cibaj Originator: Jessica L. Zichichi Originator: Emily A. Himmelstoss Originator: E. Robert Thieler Publication_Date: 2026 Title: Digital Shoreline Analysis System version 6.1 Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: software release Issue_Identification: version 6.1.177 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: Use the first link to access the publication page. The second link is to the current version of DSAS (v6.1). The third link directs to the DSAS project page. Online_Linkage: https://doi.org/10.5066/P1NHMJNC Online_Linkage: https://code.usgs.gov/cch/dsas Online_Linkage: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas Cross_Reference: Citation_Information: Originator: Peter Ruggiero Originator: Jeffrey H. List Publication_Date: 200909 Title: Improving Accuracy and Statistical Reliability of Shoreline Position and Change Rate Estimates Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: Journal of Coastal Research Issue_Identification: vol. 255 Publication_Information: Publication_Place: n/a Publisher: Coastal Education and Research Foundation Other_Citation_Details: pp. 1069-1081 Online_Linkage: https://doi.org/10.2112/08-1051.1 Cross_Reference: Citation_Information: Originator: Amy S. Farris Originator: Kathryn M. Weber Originator: Kara S. Doran Originator: Jeffrey H. List Publication_Date: 2018 Title: Comparing methods used by the U.S. Geological Survey Coastal and Marine Geology Program for deriving shoreline position from lidar data Series_Information: Series_Name: Open-File Report Issue_Identification: 2018–1121 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: suggested citation: Farris, A.S., Weber, K.M., Doran, K.S., and List, J.H., 2018, Comparing methods used by the U.S. Geological Survey Coastal and Marine Geology Program for deriving shoreline position from lidar data: U.S. Geological Survey Open-File Report 2018–1121, 13 p., https://doi.org/10.3133/ofr20181121 Online_Linkage: https://doi.org/10.3133/ofr20181121 Cross_Reference: Citation_Information: Originator: Kathryn M. Weber Originator: Jeffrey H. List Originator: Karen L.M. Morgan Publication_Date: 2005 Title: An operational mean high water datum for determination of shoreline position from topographic lidar data Series_Information: Series_Name: Open-File Report Issue_Identification: 2005-1027 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.3133/ofr20051027 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The data provided here are a compilation of shorelines from multiple sources, spanning 173 years. The attributes are based on the requirements of the Digital Shoreline Analysis System (DSAS) software and have gone through a series of quality assurance procedures. Logical_Consistency_Report: Adjacent shoreline segments do not overlap and are not necessarily continuous. Shorelines were quality checked for accuracy. Any slight offsets between adjacent segments due to georeferencing and digitizing error are taken into account in the uncertainty of the shoreline position, as reported in the horizontal accuracy section of this metadata file. Completeness_Report: This shoreline file is complete and contains all shoreline segments used to calculate shoreline change rates along sections of the Alabama coastal region where shoreline position data were available. These data adequately represented the shoreline position at the time of the survey. Gaps in these data, if applicable, are a consequence of non-existing data or existing data that did not meet quality assurance standards. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The horizontal accuracy of the shoreline data varies with respect to the data source from which the shorelines were digitized, the lidar data from which the shorelines were extracted, the time period, and the method used to extract the shoreline data. T-sheet Shoreline Positional Uncertainty: Shorelines prior to 1960 (T-sheets) have an estimated positional uncertainty of plus or minus 10.8 meters (m). Shorelines from the 1960s-1980s (T-sheets) have an estimated positional uncertainty of plus or minus 5.1 m. Contour Shoreline Positional Uncertainty: Four sources of uncertainty were accounted for regarding shorelines extracted using the contour method (described in Farris and others, 2018): 1) The vertical uncertainty of the lidar data (0.15 - 0.29 m) as found in the original lidar source metadata; 2) the horizontal uncertainty of the lidar data (0.12 - 1.0 m) as found in the original lidar source metadata; 3) a mean high water (MHW) vertical uncertainty of 0.15 m (Weber and others, 2005); and 4) a horizontal uncertainty due to the creation of a Digital Elevation Model (DEM) from lidar point cloud data (0.5 m). The vertical uncertainty values (1 and 3 above) were converted to a horizontal uncertainty using the beach slope in order to calculate uncertainty by summation in quadrature of horizontal components. The beach slope was found by averaging slope values calculated from the lidar profile shorelines (see process steps for a description). Vertical uncertainty (VU) terms were divided by the average beach slope (expressed as rise/run) in order to get the horizontal component of the two vertical uncertainty terms: VU/TAN(slope*(3.14159/180)). In order to estimate the total horizontal uncertainty, the four horizontal components of uncertainty were added in quadrature (square root of the sum of the squares). These values are stored in the attribute table as Uncy. The average uncertainty, in meters, for the contour shorelines are as follows: AL 1998 = 3.01 m AL 2005 = 3.49 m AL 2007 = 3.07 m AL 2010 = 3.27 m AL 2015 = 1.86 m AL 2016 = 2.08 m AL 2018 (USACE) = 1.98 m AL 2018 (USGS) = 1.72 m AL 2020 = 2.42 m AL 2022 = 1.98 m Profile shoreline extraction was completed for three lidar datasets (AL 2010, AL 2016 and AL 2022). Profile Shoreline Positional Uncertainty: Four sources of uncertainty were accounted for regarding shorelines extracted using the profile method (method described in Farris and others, 2018): 1) the 95% confidence interval on the linear regression estimate of the shoreline position; 2) the uncertainty associated with the elevation of the raw lidar data; 3) a 15 cm vertical error in our chosen value of MHW; and 4) the uncertainty due to extrapolation (if the shoreline was determined using extrapolation). These components of uncertainty were added in quadrature to yield a total error for each shoreline point. These errors were averaged for each profile shoreline segment (up to 2 kilometers). The range of uncertainty the profile shorelines used is 0.99 to 5.25 m, with an average of 2.83 m (AL 2010), 2.05 m (AL 2016), and 1.87 m (AL 2022). See the Uncy field in the shorelines attribute table for the individual uncertainty values of profile shoreline segments. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Himmelstoss, E.A. Originator: Kratzmann, M.G. Originator: Thieler, E.R. Publication_Date: 2017 Title: National assessment of shoreline change – A GIS compilation of updated vector shorelines and associated shoreline change data for the Gulf of Mexico coast Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/F78P5XNK Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: Alabama shoreline data from DOI:10.5066/F78P5XNK Online_Linkage: https://doi.org/10.5066/F78P5XNK Online_Linkage: https://www.sciencebase.gov/catalog/item/582ca4a5e4b04d580bd378ec Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1849 Ending_Date: 2001 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Historical shorelines 1849-2001 Source_Contribution: Historical shorelines (T-sheet-derived, for example) from this publication (DOI:10.5066/F78P5XNK, downloaded in 2025) were used in the shoreline change analysis. Source_Information: Source_Citation: Citation_Information: Originator: Henderson, R.E. Originator: Nelson, P.R. Originator: Long, J.W. Originator: Smith, C.G. Publication_Date: 2017 Title: Vector shorelines and associated shoreline change rates derived from lidar and aerial imagery for Dauphin Island, Alabama: 1940–2015 Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/F7T43RB5 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: Dauphin Island, Alabama, shoreline data from DOI:10.5066/F7T43RB5 Online_Linkage: https://doi.org/10.5066/F7T43RB5 Online_Linkage: https://coastal.er.usgs.gov/data-release/doi-F7T43RB5/ Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1940 Ending_Date: 2015 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Dauphin shorelines 1940-2015 Source_Contribution: MHW lidar shorelines (1998-2014) and WDL proxy shorelines (1940-2015) from this publication (DOI:10.5066/F7T43RB5, downloaded in 2025) were used in the Alabama shoreline change analysis. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Publication_Date: 2022 Title: 1998 Fall Gulf Coast NOAA/USGS/NASA Airborne LiDAR Assessment of Coastal Erosion (ALACE) Project for the US Coastline Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=22 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/48152 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19981029 Ending_Date: 19981109 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 1998 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 11/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2022 Title: 2005 US Army Corps of Engineers (USACE) Post-Hurricane Katrina Topo/Bathy Project for the Alabama, Florida, Louisiana and Mississippi Coasts Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=31 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/50056 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20051012 Ending_Date: 20051211 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2005 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 11/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2022 Title: 2007 USGS/NPS/NASA Experimental Advanced Airborne Research Lidar (EAARL): Northern Gulf of Mexico Barrier Islands Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=522 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/50105 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20070627 Ending_Date: 20070630 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2007 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 09/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2010 USACE NCMP Topobathy Lidar: Gulf Coast (AL, FL) Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=1064 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/50083 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 201001 Ending_Date: 201003 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2010 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (profile and contour methods). Data accessed and downloaded in 08/2025 and 09/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2015 USGS Lidar: South Terrebonne and Gulf Islands, LA Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Dauphin Island, Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=10143 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/73667 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20150118 Ending_Date: 20150213 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2015 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 09/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2016 USACE NCMP Topobathy Lidar: Gulf Coast (AL, FL, MS, TX) Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=5186 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/49738 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20160723 Ending_Date: 20161010 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2016 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (profile method). Data accessed and downloaded in 06/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2016 USACE NCMP Topobathy Lidar DEM: Gulf Coast (AL, FL, MS, TX) Geospatial_Data_Presentation_Form: raster digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: DEM data were downloaded for Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=6371 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/49427 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20160723 Ending_Date: 20161010 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2016 DEM Source_Contribution: The elevation data were downloaded as DEM tiles for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 09/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2018 USGS Topobathy Lidar: Gulf Coast Islands (AL, FL, LA) Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Dauphin Island, Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9117 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/64345 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20181027 Ending_Date: 20181103 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2018 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 09/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2018 USACE NCMP Topobathy Lidar DEM: Gulf Coast (AL, MS) Geospatial_Data_Presentation_Form: raster digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: DEM data were downloaded for mainland Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8668 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/55862 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20181030 Ending_Date: 20181030 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2018 DEM Source_Contribution: The elevation data were downloaded as DEM tiles for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 07/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA National Geodetic Survey Publication_Date: 2026 Title: 2019 - 2020 NOAA NGS Topobathy Lidar DEM: Hurricane Michael (NW Florida) Geospatial_Data_Presentation_Form: raster digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: DEM data were downloaded for Alabama (Block 6, Time Frame 5). Alabama dataset date= 02/22/2020. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9708 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/69338 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20191204 Ending_Date: 20200502 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2020 DEM Source_Contribution: The elevation data were downloaded as DEM tiles for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 07/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2022 USACE NCMP Topobathy Lidar: Gulf Coast (AL, FL, MS) Geospatial_Data_Presentation_Form: vector digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: Point cloud data were downloaded for Alabama. Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=10314 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/75435 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20220717 Ending_Date: 20220719 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2022 PTS Source_Contribution: The elevation data were downloaded as a point cloud (.laz) for extraction of datum-based shoreline (profile method). Data accessed and downloaded in 08/2025. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Office for Coastal Management Partners Publication_Date: 2026 Title: 2022 USACE NCMP Topobathy Lidar DEM: Gulf Coast (AL, FL, MS) Geospatial_Data_Presentation_Form: raster digital dataset Publication_Information: Publication_Place: Charleston, SC Publisher: Office for Coastal Management Other_Citation_Details: DEM data were downloaded for Alabama (Time Frame 1). Projection = NAD_1983_2011_UTM_Zone_16N. Online_Linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=10315 Online_Linkage: https://www.fisheries.noaa.gov/inport/item/75692 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20220717 Ending_Date: 20220719 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: AL 2022 DEM Source_Contribution: The elevation data were downloaded as DEM tiles for extraction of datum-based shoreline (contour method). Data accessed and downloaded in 09/2025. Process_Step: Process_Description: Historical shoreline data for Alabama were downloaded from a previous USGS publication (DOI:10.5066/F78P5XNK) and underwent basic quality checks and minor edits to the attribute table. The historical data contain proxy-based shorelines that represent the high-water line (HWL) at the time of survey and include one datum-based lidar shoreline from 2001. Source_Used_Citation_Abbreviation: DOI:10.5066/F78P5XNK shorelines Process_Date: 2025 Source_Produced_Citation_Abbreviation: Historical shorelines 1849-2001 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Meredith Kratzmann Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: mkratzmann@contractor.usgs.gov Process_Step: Process_Description: Shoreline data for Dauphin Island, Alabama were downloaded from a previous USGS publication (DOI:10.5066/F7T43RB5) and underwent basic quality checks and minor edits to shorelines and attribute table. The data contain proxy-based shorelines that represent the wet-dry line (WDL) at the time of the aerial survey (1940-2015) and include datum-based mean high water (MHW) lidar shorelines from 1998-2014. Source_Used_Citation_Abbreviation: DOI:10.5066/F7T43RB5 shorelines Process_Date: 2025 Source_Produced_Citation_Abbreviation: Dauphin shorelines 1940-2015 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Meredith Kratzmann Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: mkratzmann@contractor.usgs.gov Process_Step: Process_Description: Overview of the methods used to extract shoreline features from lidar data for Alabama: In this data release, two methods of shoreline extraction from lidar were used: the contour method and the profile method. Both methods use the Mean High Water (MHW) elevation from Weber and others (2005) for shoreline extraction. Described in Farris and others (2018), the contour method extracts the elevation of average MHW value from DEM data using the ArcGIS Pro tool Contour List with the MHW value chosen as the contour. Also described in Farris and others (2018), the profile method produces a datum-based mean high water (MHW) shoreline. The profile method extracts the MHW shoreline point from the lidar point cloud data, using a cross shore transect in a MATLAB-based approach. Please see subsequent process steps for details. These shorelines are polyline shapefiles that may be referred to as "profile shorelines" or "contour shorelines" in this metadata document to distinguish extraction methods, but note they are both lidar-derived. Process_Date: 2025 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Meredith Kratzmann Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: mkratzmann@contractor.usgs.gov Process_Step: Process_Description: The following information applies to Alabama shorelines extracted using the profile method for the years 2010, 2016, and 2022. The profile method is used to extract the operational MHW shoreline from lidar point cloud data utilizing a MATLAB-based approach (MATLAB version R2024A) and is described in Farris and others (2018). The profile method used a coast-following reference line with 20-meter spaced profiles. All lidar data points that were within 1 meter of each profile line were associated with that profile. All processing was done on the 2-meter-wide profiles, working on a single profile at a time. For each profile, a linear regression was fit through data points on the foreshore and the regression was evaluated at the MHW elevation to yield the cross-shore position of the MHW shoreline. If there was a data gap at MHW or if the MHW elevation was obscured by water points, the linear regression was simply extrapolated to the MHW elevation. For each profile, the foreshore beach slope was defined as the slope of the regression line. This slope information is combined for all surveys and used to calculate uncertainty for profile- and contour-derived shorelines. The uncertainty associated with profile shorelines is described in the Horizontal Positional Accuracy Report of this metadata file. Source_Used_Citation_Abbreviation: AL 2010 PTS Source_Used_Citation_Abbreviation: AL 2016 PTS Source_Used_Citation_Abbreviation: AL 2022 PTS Process_Date: 2025 Source_Produced_Citation_Abbreviation: AL 2010 profile shoreline Source_Produced_Citation_Abbreviation: AL 2016 profile shoreline Source_Produced_Citation_Abbreviation: AL 2022 profile shoreline Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Amy S. Farris Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: afarris@usgs.gov Process_Step: Process_Description: Profile shorelines were prepared for use in DSAS. Attribute fields were added using ArcGIS Pro tool Add Fields (multiple): Geoprocessing > Data Management Tools > Fields > Add Fields (multiple). Fields added: Date_ (text), Uncy (Float), Source (text), Source_b (text), Year_ (Short), Default_D (Short), DSAS_Type (text), STATE (text), SRCE_INFO (text), DEM (text), MHW_elev (Double), Slope_ (Float). See the Entity Attributes section of this metadata file for definitions. All profile shorelines for Alabama were then merged into a single file using the ArcGIS Pro tool Merge: Geoprocessing > Data Management Tools > General > Merge. This and the following steps were performed by the same person: Meredith Kratzmann. Source_Used_Citation_Abbreviation: AL 2010 profile shoreline Source_Used_Citation_Abbreviation: AL 2016 profile shoreline Source_Used_Citation_Abbreviation: AL 2022 profile shoreline Process_Date: 2025 Source_Produced_Citation_Abbreviation: AL profile shorelines Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Meredith Kratzmann Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: mkratzmann@contractor.usgs.gov Process_Step: Process_Description: An inventory was conducted to identify all available lidar datasets for Alabama that were not included in the previous USGS publications (DOI:10.5066/F78P5XNK; DOI:10.5066/F7T43RB5). Datasets that met quality assurance standards for this analysis were processed for extraction using the contour method (described in Farris and others, 2018). Contour shorelines that were extracted for Alabama include the years: 1998, 2005, 2007, 2010, 2015, 2016, 2018, 2020, and 2022. In some cases, contour shoreline segments were used to fill in gaps of a profile shoreline extracted from the same dataset to provide more complete coverage. Process_Date: 2025 Process_Step: Process_Description: Datasets that were available as DEMs were downloaded from the NOAA Digital Coast Data Access viewer (https://coast.noaa.gov/dataviewer/#/lidar/search/): Projection= UTM; Zone= 16N; Horizontal Datum= NAD83; Vertical Datum= NAVD88; Output format= Raster (GeoTIFF); DEM cell size= 1 meter. Workflow used to extract a contour shoreline from a DEM: 1) DEM loaded into ArcGIS Pro v.3.5.5 2) Created contour polyline using ArcGIS Pro tool Contour List: Geoprocessing > Spatial Analyst Tools > Surface > Contour List. Input raster= DEM; Output polyline features= contour shoreline; Contour value= MHW (Alabama = 0.23). 3) Output contour edited as necessary to capture open-ocean sandy shoreline by visually comparing the line to imagery within ArcGIS Pro. 4) Contour shoreline smoothed using ArcGIS Pro tool Smooth Line: Geoprocessing > Cartography Tools > Generalization > Smooth Line. Smoothing algorithm= Polynomial Approximation with Exponential Kernel (PAEK); Smoothing tolerance= 5 meters. 5) Attribute fields were added to the contour shoreline using ArcGIS Pro tool Add Fields (multiple): Geoprocessing > Data Management Tools > Fields > Add Fields (multiple). Fields added: Date_ (text), Uncy (Float), Source (text), Source_b (text), Year_ (Short), Default_D (Short), DSAS_Type (text), STATE (text), SRCE_INFO (text), DEM (text), MHW_elev (Double), Slope_ (Float). See the Entity Attributes section of this metadata file for definitions. Source_Used_Citation_Abbreviation: AL 2016 DEM Source_Used_Citation_Abbreviation: AL 2018 DEM Source_Used_Citation_Abbreviation: AL 2020 DEM Source_Used_Citation_Abbreviation: AL 2022 DEM Process_Date: 2025 Source_Produced_Citation_Abbreviation: AL 2016 contour shoreline Source_Produced_Citation_Abbreviation: AL 2018 contour shoreline USACE Source_Produced_Citation_Abbreviation: AL 2020 contour shoreline Source_Produced_Citation_Abbreviation: AL 2022 contour shoreline Process_Step: Process_Description: Datasets that were not available as DEMs were downloaded as lidar point cloud files in Lidar Aerial Survey (LAS) format compressed to a ZIP format (LAZ) from the NOAA Digital Coast Data Access viewer (https://coast.noaa.gov/dataviewer/#/lidar/search/): Projection= UTM; Zone= 16N; Horizontal Datum= NAD83; Vertical Datum= NAVD88; Geoid= GEOID18; Output format= Points - LAZ; Data classes= Ground; Return Types= Any. The point cloud was used to create a DEM. 1) In ArcGIS Pro v.3.5.5, LAZ files were decompressed using the Convert LAS tool: Geoprocessing > Conversion Tools > Point Cloud > Convert LAS. Compression= No compression; File version= Same As Input; LAS Options= unchecked; Define Input Coordinate System= No LAS Files. Output= LAS files. 2) LAS files were combined into a LAS dataset (LASD) using ArcGIS Pro tool Create LAS Dataset: Geoprocessing > Data Management Tools > LAS Dataset > Create LAS Dataset. Coordinate system= NAD_1983_2011_UTM_Zone_16N. 3) The LASD file was converted to a DEM using ArcGIS Pro tool LAS Dataset to Raster: Geoprocessing > Conversion Tools > Point Cloud > LAS Dataset to Raster. Value field= Elevation; Interpolation Type= Binning Average Linear; Output data type= Floating Point; Sampling Type= Cell Size; Sampling Value= 1 or 3; Z Factor= 1. Source_Used_Citation_Abbreviation: AL 1998 PTS Source_Used_Citation_Abbreviation: AL 2005 PTS Source_Used_Citation_Abbreviation: AL 2007 PTS Source_Used_Citation_Abbreviation: AL 2010 PTS Source_Used_Citation_Abbreviation: AL 2015 PTS Source_Used_Citation_Abbreviation: AL 2018 PTS Process_Date: 2025 Source_Produced_Citation_Abbreviation: AL 1998 DEM Source_Produced_Citation_Abbreviation: AL 2005 DEM Source_Produced_Citation_Abbreviation: AL 2007 DEM Source_Produced_Citation_Abbreviation: AL 2010 DEM Source_Produced_Citation_Abbreviation: AL 2015 DEM Source_Produced_Citation_Abbreviation: AL 2018 DEM Process_Step: Process_Description: Using the DEMs created from point cloud data, a contour shoreline was extracted by the same workflow outlined above using the Contour List tool and edited/smoothed in ArcGIS Pro 3.5.5. Attribute fields were added to the contour shoreline using the tool Add Fields (multiple). Source_Used_Citation_Abbreviation: AL 1998 DEM Source_Used_Citation_Abbreviation: AL 2005 DEM Source_Used_Citation_Abbreviation: AL 2007 DEM Source_Used_Citation_Abbreviation: AL 2010 DEM Source_Used_Citation_Abbreviation: AL 2015 DEM Source_Used_Citation_Abbreviation: AL 2018 DEM Process_Date: 2025 Source_Produced_Citation_Abbreviation: AL 1998 contour shoreline Source_Produced_Citation_Abbreviation: AL 2005 contour shoreline Source_Produced_Citation_Abbreviation: AL 2007 contour shoreline Source_Produced_Citation_Abbreviation: AL 2010 contour shoreline Source_Produced_Citation_Abbreviation: AL 2015 contour shoreline Source_Produced_Citation_Abbreviation: AL 2018 contour shoreline USGS Process_Step: Process_Description: All lidar datasets used in this release contain date values that are provided in the raw data as GPS time. These values were converted to a calendar date for use in DSAS via Python code written by Zehao Xue and Amy Farris of USGS. Process_Date: 2025 Process_Step: Process_Description: Attribute fields were populated for each of the lidar shorelines. Process_Date: 2025 Process_Step: Process_Description: All contour shorelines were then merged into a single file using the ArcGIS Pro tool Merge: Geoprocessing > Data Management Tools > General > Merge. Source_Used_Citation_Abbreviation: AL 1998 contour shoreline Source_Used_Citation_Abbreviation: AL 2005 contour shoreline Source_Used_Citation_Abbreviation: AL 2007 contour shoreline Source_Used_Citation_Abbreviation: AL 2010 contour shoreline Source_Used_Citation_Abbreviation: AL 2015 contour shoreline Source_Used_Citation_Abbreviation: AL 2016 contour shoreline Source_Used_Citation_Abbreviation: AL 2018 contour shoreline USGS Source_Used_Citation_Abbreviation: AL 2018 contour shoreline USACE Source_Used_Citation_Abbreviation: AL 2020 contour shoreline Source_Used_Citation_Abbreviation: AL 2022 contour shoreline Process_Date: 2025 Source_Produced_Citation_Abbreviation: AL contour shorelines Process_Step: Process_Description: Historical shorelines were merged with the lidar shorelines in ArcGIS Pro v3.5.5 to produce a single shorelines file for Alabama using the Merge tool. A length field (Length_m) was added to the merged shorelines file using XTools v25.0: Tools > Calculate Geometry. Parameter= length; Output units= meters. Source_Used_Citation_Abbreviation: Historical shorelines 1849-2001 Source_Used_Citation_Abbreviation: Dauphin shorelines 1940-2015 Source_Used_Citation_Abbreviation: AL profile shorelines Source_Used_Citation_Abbreviation: AL contour shorelines Process_Date: 2025 Source_Produced_Citation_Abbreviation: AL shorelines Process_Step: Process_Description: The shorelines shapefile (AL_shorelines.shp) was imported as a layer into the Digital Shoreline Analysis System (DSAS) v6.1 software to perform rate calculations. For details, please see the DSAS project page: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas Process_Date: 2026 Process_Step: Process_Description: The shorelines shapefile was projected in ArcGIS Pro v3.5.5 > Geoprocessing > Data Management Tools > Projections and Transformations > Project. Parameters: Input Coordinate System - NAD_1983_2011_UTM_Zone_16N; Output Coordinate System - GCS_WGS_1984; transformation = WGS_1984_(ITRF08)_To_NAD_1983_2011. Process_Date: 2026 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 1123 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.0000001 Longitude_Resolution: 0.0000001 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: WGS_1984 Ellipsoid_Name: WGS_84 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257224 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: AL_shorelines Entity_Type_Definition: Shorelines for coastal Alabama used in shoreline change analysis. Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number. Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: Shape Attribute_Definition: Feature geometry. Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Feature type. Attribute: Attribute_Label: Date_ Attribute_Definition: Date of shoreline position; date of survey as indicated on source material. A default date of 07/01 was assigned to shorelines where only the year was known (month and day unknown). Using July, the mid-point month of the calendar year, minimizes the potential offset to the actual shoreline date by a maximum of six months. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Date of the shoreline is represented as MM/DD/YYYY Attribute: Attribute_Label: Uncy Attribute_Definition: Estimate of shoreline position uncertainty in meters. Actual shoreline position is within the range of this value (plus or minus, meters). The historic shoreline uncertainty values incorporate measurement uncertainties associated with mapping methods and materials for historical shorelines, the geographic registration of shoreline position, and shoreline digitizing. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.99 Range_Domain_Maximum: 13.00 Attribute: Attribute_Label: Source Attribute_Definition: Agency that provided shoreline feature or the data source used to digitize shoreline feature. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Agency name or acronym. See lineage for all data source citations. Attribute: Attribute_Label: Source_b Attribute_Definition: Type of data used to create shoreline. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: aerial - contour Enumerated_Domain_Value_Definition: Shoreline derived from Aerial Photography (contour extraction method). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: aerials; ESCYR125 Enumerated_Domain_Value_Definition: Shoreline derived from Aerial Photography (FLDEP dataset from DOI:10.5066/F78P5XNK). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: CSC data Enumerated_Domain_Value_Definition: Vector digital shoreline data from NOAA Coastal Services Center (DOI:10.5066/F78P5XNK). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: lidar - contour Enumerated_Domain_Value_Definition: Shoreline derived from lidar data (contour extraction method). Data from DOI:10.5066/F7T43RB5. Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: lidar DEM - contour Enumerated_Domain_Value_Definition: Shoreline derived from DEM created from lidar point cloud data (contour extraction method). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: lidar points - profile Enumerated_Domain_Value_Definition: Shoreline derived from lidar point cloud data (profile extraction method). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: MOG data Enumerated_Domain_Value_Definition: Vector digital shoreline data from Mississippi Department of Environmental Quality, Office of Geology (MOG) (DOI:10.5066/F78P5XNK). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: T-Sheet Enumerated_Domain_Value_Definition: Shoreline derived from NOAA Topographic Survey Sheet (T-Sheet). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: USA data Enumerated_Domain_Value_Definition: Vector digital shoreline data from University of South Alabama (USA) (DOI:10.5066/F78P5XNK). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: Year_ Attribute_Definition: Four-digit year of shoreline Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1849 Range_Domain_Maximum: 2022 Attribute: Attribute_Label: Default_D Attribute_Definition: Differentiates between shorelines that have known month and day attributes and those that use the default value of 07/01 when only the year is known. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 0 Enumerated_Domain_Value_Definition: Shoreline month and day are known. Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 1 Enumerated_Domain_Value_Definition: Shoreline month and day are unknown and default value of 07/01 was used. Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: DSAS_type Attribute_Definition: Shoreline type field used to specify the proxy or datum to which the shoreline is referenced. It is a required field when proxy-based and datum-based shorelines are combined to compute rates in DSAS. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: MHW Enumerated_Domain_Value_Definition: Mean High Water (datum-based shoreline). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: HWL Enumerated_Domain_Value_Definition: High Water Line (proxy-based shoreline). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: WDL Enumerated_Domain_Value_Definition: Wet-Dry Line (proxy-based shoreline). Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: STATE Attribute_Definition: U.S. State where the shoreline data are located. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: ALABAMA Enumerated_Domain_Value_Definition: Shoreline data are within the borders of Alabama. Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: SRCE_INFO Attribute_Definition: Information regarding source data used to digitize or extract the shoreline feature. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Character string of length 50 Attribute: Attribute_Label: DEM Attribute_Definition: Description of DEM used to extract shoreline feature. Example of DEM (GeoTIFF) filename downloaded from NOAA Digital Coast Data Access Viewer: usace2022_gulf_dem_J1218431tR0_C1. DEMs created from point cloud data are noted. A null value of 9999 indicates that the shoreline was not extracted from a DEM. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Character string of length 100 Attribute: Attribute_Label: MHW_elev Attribute_Definition: Value of average MHW elevation (meters above NAVD88) that was used to extract the contour shoreline from DEM or point cloud data. A null value of 9999 represents a shoreline not extracted with a MHW value (such as proxy-based T-sheet data). Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 0.23 Enumerated_Domain_Value_Definition: Average MHW elevation (meters above NAVD88) for Alabama. Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 9999 Enumerated_Domain_Value_Definition: Null value Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: Slope_ Attribute_Definition: The foreshore beach slope calculated during the profile shoreline extraction process (see process step for details). Slope values were only calculated for lidar shorelines extracted by the profile method. All other segments have a null value of 9999. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1.89 Range_Domain_Maximum: 16.89 Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 9999 Enumerated_Domain_Value_Definition: Null value Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: Length_m Attribute_Definition: Length of shoreline segment in meter units (NAD_1983_2011_UTM_Zone_16N). Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 2.037 Range_Domain_Maximum: 29725.090 Overview_Description: Entity_and_Attribute_Overview: The entity and attribute information provided here describes the tabular data associated with the dataset. Please review the individual attribute descriptions for detailed information. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - ScienceBase Contact_Address: Address_Type: mailing and physical address Address: Federal Center, Building 810, MS 302 City: Denver State_or_Province: CO Postal_Code: 80225 Country: USA Contact_Voice_Telephone: 1-888-275-8747 Contact_Electronic_Mail_Address: sciencebase@usgs.gov Resource_Description: The dataset contains polyline shorelines (SHP and other shapefile components), browse graphic, and the FGDC CSDGM metadata. Distribution_Liability: Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: Shapefile Format_Version_Number: ArcGIS Pro version 3.5.5 Format_Specification: Esri polyline shapefile (compressed to ZIP format) Format_Information_Content: These files (.cpg, .dbf, .prj, .sbn, .sbx, .shp, .html, and .shx) are a collection of files with a common filename prefix and must be downloaded and stored in the same directory. Together they are the components of the shapefile. Transfer size is in MB. File_Decompression_Technique: Unzip Transfer_Size: 6.44 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P1JE2KSO Network_Resource_Name: https://www.sciencebase.gov/catalog/item/69e2b013b66b0195694c11e7 Network_Resource_Name: https://www.sciencebase.gov/catalog/file/get/69e2b013b66b0195694c11e7 Access_Instructions: The first link is to the USGS publication page, the second link is to the dataset page, and the third link downloads the data. Fees: None Technical_Prerequisites: These data are available in a polyline shapefile format. The user must have software to read and process the data components of a shapefile. Metadata_Reference_Information: Metadata_Date: 20260622 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Meredith G. Kratzmann Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: whsc_data_contact@usgs.gov Contact_Instructions: The metadata contact email address is a generic address in the event the person is no longer with USGS. Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time