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Baseline_OpenOcean.shp - Baseline Along the Open-Ocean (South-Facing) Coast of Dauphin Island, Alabama, Generated to Calculate Shoreline Change Rates.

Metadata Updated: October 30, 2025

Analysis of shoreline change for Dauphin Island, Alabama was conducted using the U.S. Geological Survey (USGS) Digital Shoreline Analysis System (DSAS) v.4.3 for ArcMap (Thieler and others, 2009) and vector shorelines derived from air photos and lidar elevation surveys. DSAS-generated transects were cast at 100-meter intervals along a user defined shore-parallel baseline. The intersections of transects with the mean high water (MHW) shoreline positions are identified by intercept points. The rate of shoreline change was determined by measuring the differences in the distance to each historical shoreline position from the baseline along each transect. Three analyses of change rates were conducted using a combination of shorelines derived from different data sources. Shoreline change rates from the wet dry line (WDL) shoreline were derived from 10 sets of air photos from 1940 - 2015. Rates of change were also calculated using MHW shorelines extracted from 14 lidar datasets from 1998 - 2014. A final change analysis was conducted using a combination of all WDL (aerial) and MHW (lidar) shorelines, from 1940 - 2015.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date September 14, 2025
Metadata Updated Date October 30, 2025

Metadata Source

Harvested from DOI USGS DCAT-US

Additional Metadata

Resource Type Dataset
Metadata Created Date September 14, 2025
Metadata Updated Date October 30, 2025
Publisher U.S. Geological Survey
Maintainer
Identifier http://datainventory.doi.gov/id/dataset/usgs-3ccdad31-2e42-4078-afe8-6aacfbdefd1e
Data Last Modified 2021-09-22T00:00:00Z
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://ddi.doi.gov/usgs-data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 2cb1acc1-db42-4696-adc4-2c76b1668d2b
Harvest Source Id 2b80d118-ab3a-48ba-bd93-996bbacefac2
Harvest Source Title DOI USGS DCAT-US
Metadata Type geospatial
Old Spatial -88.347879, 30.236274, -88.070565, 30.222423
Source Datajson Identifier True
Source Hash ef8c26915d574af5e29eeb10c3027e3377bf40d1548001f5cf5f667ba2d9bfbc
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -88.347879, 30.236274, -88.347879, 30.222423, -88.070565, 30.222423, -88.070565, 30.236274, -88.347879, 30.236274}

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