Title:Breton Island, Louisiana Baseline (Geographic, NAD83) Abstract:
Breton Island, Louisiana Baseline (Geographic, NAD83) consists of vector line data that were input into the Digital Shoreline Analysis System (DSAS) version 4.0, which is computer software used to compute rate of change statistics. A baseline was acquired from the Barrier Island Comprehensive Monitoring Program (BICM) 2009 report (http://lacoast.gov/reports/project/3890772~1.pdf). The baseline included in the BICM report covered the entire Louisiana coastline, so the baseline representing Breton Island had to be clipped then exported to a new shapefile named Breton_Baseline.shp. The position relative to Breton Island was determined to be the best possible baseline to use for the study. The baseline file was used to create the transect files, which are required by the DSAS program to calculate rate of change statistics.
Terrano, Joseph F., Smith, Kathryn E., and Flocks, James G., 20160125, Breton Island, Louisiana Baseline (Geographic, NAD83): U.S. Geological Survey Data Release doi:10.5066/F7XS5SGM, U.S. Geological Survey, St. Petersburg, FL.
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest 0.6096
Ordinates (y-coordinates) are specified to the nearest 0.6096
Planar coordinates are specified in meter
The horizontal datum used is D North American 1983.
The ellipsoid used is GRS 1980.
The semi-major axis of the ellipsoid used is 6378137.0.
The flattening of the ellipsoid used is 1/298.257222101.
Funds for this report are part of project funds for the Louisiana Outer Coast Early Restoration Project, obtained by the natural resource trustees for the Deepwater Horizon Oil Spill, pursuant to the Framework for Early Restoration Addressing Injuries Resulting from the Deepwater Horizon Oil Spill executed April 20, 2011. USFWS is the project lead for the North Breton Island Barrier Island Restoration project. Acknowledgment of the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, as a data source would be appreciated in products developed from these data, and such acknowledgment as is standard for citation and legal practices. Sharing of new data layers developed directly from these data would also be appreciated by the U.S. Geological Survey staff. Users should be aware that comparisons with other datasets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in photointerpretation, mapping conventions, and digital processes over time. These data are not legal documents and are not to be used as such.
The baseline was digitized as a single vector line parallel to, and seaward of, the Breton Island shorelines. The baseline serves as a starting point for the DSAS program to cast transects. For this analysis, transects were spaced out at a 50-meter (m) interval across the baseline.
Luis Martinez, Sean O’Brien, Matt Bethel, Shea Penland and Mark Kulp, 2009, Louisiana Barrier Island Comprehensive Monitoring Program (BICM) Volume 2: Shoreline Changes and Barrier Island Land Loss 1800’s‐2005.
The baseline data downloaded from the BICM 2009 report encompassed the entire state of Louisiana; however, this project’s study area was restricted to Breton Island. Therefore, the BICM baseline was clipped using ArcMap 10.2 to match the study area extents, prior to the baseline being exported to a new shapefile named Breton_Baseline.shp. Breton_Baseline.shp was used to analyze the following time periods: (1) 1869-2014 (long term), (2) pre-1950s (before excavation of the MRGO), (3) post- 1950s (post MRGO), (4) post- Hurricane Katrina (short term), and (5) pre/post Hurricane Katrina (acute weather event). The baseline was used to generate perpendicular transects at a 50-m interval.
Person who carried out this activity:
U.S. Geological Survey
Attn: Joseph Terrano
600 4th Street South
St. Petersburg, Florida
(727) 502-8047 (voice)
(727) 502-8001 (FAX)
Monday through Friday, 9:00 a.m. to 5:00 p.m., Eastern Standard Time
Date: 13-Oct-2020 (process 2 of 2)
Added keywords section with USGS persistent identifier as theme keyword.
Person who carried out this activity:
Where are the gaps in the data? What is missing?
This dataset is considered complete for the information presented, as described in the abstract section. Users are advised to read the rest of the metadata record carefully for additional details.
This digital publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.