Joseph F. Terrano Kathryn E. Smith James G. Flocks 20160125 vector digital data (Polyline) U.S. Geological Survey Data Release doi:10.5066/F7XS5SGM St. Petersburg, FL U.S. Geological Survey http://coastal.er.usgs.gov/data-release/doi-F7XS5SGM/ Breton Island, Louisiana Transects with Shoreline Change Rates (Pre-1950s) (Geographic, NAD83) consists of vector transect data that were derived from the Digital Shoreline Analysis System (DSAS) version 4.0. Rates from the DSAS statistical output table were joined to the transects to provide a visual representation of the shoreline change rates on a transect-by-transect basis. Transect data are considered a crucial element in performing change analysis for erosion and accretion studies and for tracking shoreline movement over time. DSAS uses transects as a method to extract shoreline change rates from shorelines at a given interval across a baseline. For this long term analysis, transects were spaced out at a 50-m interval across the baseline and shoreline change rates were calculated for the historical long-term (Pre-1950s). Transect and rate attribute tables were joined to allow the rate values to be visualized on a map. 18690101 19500501 ground condition Complete None planned -89.229979 -89.145810 29.508040 29.452066 USGS Metadata Identifier USGS:2a4fe327-789d-44fa-a0b1-62036cef4068 None Coastal Transect data transect transect map Linear Regression End Point Rate Rate of change Net Shoreline Movement Weighted Linear Regression Shoreline Change Extent ISO 19115 Topic Category Oceans Environment GeoscientificInformation None LA Breton Island Gulf of Mexico Louisiana USA None Pre-1950s None The U.S. Geological Survey requests to be acknowledged as originator of the data in future products or derivative research. U.S. Geological Survey Coastal and Marine Science Center Joseph F. Terrano Researcher 1 mailing and physical

600 4th Street South

St. Petersburg Florida 33701 US (727) 502-8047 (727) 502-8001 jterrano@usgs.gov Monday through Friday, 9:00 a.m. to 5:00 p.m., Eastern Standard Time 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. Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.2.2.3552 Thieler, E.R., Himmelstoss, E.A., Zichichi, J.L., and Ergul, Ayhan 2009 http://woodshole.er.usgs.gov/project-pages/DSAS/version4/ Transects were generated as a product of the DSAS program at a 50-m interval. These transects were checked to ensure an even distribution and coverage of the shoreline datasets. Transects with errors or no rate values for all statistic fields were removed to ensure that only valid rates of change were used in the analysis. Errors included "null" and "0" values, which represent a transect that crossed only 0 or 1 shoreline and skewed the results. When joining the rates to the transect attribute table, the WLR and LRR fields could not contain a "null" value so null values are represented as a "-9999". These values should be checked and removed if using in any further analysis. The remaining transects with rates were used to aid in the final shoreline change results. Thieler, E.R., Himmelstoss, E.A., Zichichi, J.L., and Ergul, Ayhan 2009 vector digital data http://woodshole.er.usgs.gov/project-pages/DSAS/version4/ 1500 Online 18690101 19500501 ground condition Breton_DSAS_Transects_Pre_1950s DSAS was used to generate the transects at a 50-m interval. A single transect file was created and five copies were created, one for each of the analysis time periods of: (1) 1869-2014 (long-term), (2) pre-1950s (before excavation of the MRGO), (3) post-1950s (post MRGO), (4) post-Hurricane Katrina (2005-2014) (short-term), and (5) pre/post Hurricane Katrina (2004-2005)(acute weather event). Transects were generated at a 50-meter interval perpendicular to the baseline and consisted of 211 transects. Transects were removed in areas where less than two shorelines were present. Rates of change were calculated for: (1) net shoreline movement (NSM); (2) shoreline change envelope (SCE); (3) end point rate (EPR); (4) linear regression rate (LRR), and (5) weighted linear regression rate (WLR) and saved to a table, in the ArcGIS personal geodatabase format. The rate table generated by DSAS was then joined to the respective transect file so the rate values could be displayed on a map. In joining the rates to the transect table, the WLR and LRR fields were not able to use a "null" value so null values are represented as a "-99999". These values should be checked and removed if using in any further analysis. 20150601 U.S. Geological Survey Joseph Terrano mailing and physical

600 4th Street South

St. Petersburg Florida 33701 US (727) 502-8047 (727) 502-8001 jterrano@usgs.gov Monday through Friday, 9:00 a.m. to 5:00 p.m., Eastern Standard Time Added keywords section with USGS persistent identifier as theme keyword. 20201013 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 Vector String 192 Universal Transverse Mercator 16 0.9996 -87.0 0.0 500000.0 0.0 coordinate pair 0.6096 0.6096 meter D North American 1983 GRS 1980 6378137.0 298.257222101 Breton_Transects_with_Rates_Pre_1950s Transects with rate of change statistics for Breton Island from the Pre-1950s analysis. USGS FID Internal feature number. ESRI Sequential unique whole numbers that are automatically generated. Shape Feature Geometry ESRI Coordinates defining the features TransOrder Value automatically assigned, by DSAS, to each transect in a sequential order and used for identification purposes. Values are missing if the line was removed due to errors in earlier processing. USGS 6 197 StartX Starting X coordinate of each transect, in meters. USGS 284366.98 291891.61 StartY Starting Y coordinate of each transect, in meters. USGS 3260140.25 3264899.01 EndX End X coordinate of each transect, in meters. USGS 283839.61 287096.28 EndY End Y coordinate of each transect, in meters. USGS 3265112.36 3266195.26 Azimuth Azimuth of the transect measured in degrees clockwise of north. DSAS 283.94 354.52 EPR End Point Rate DSAS -14.74 1.95 SCE Shoreline Change Envelope DSAS 20.53 1198.98 NSM Net Shoreline Movement DSAS -1198.98 158.69 WLR Weighted Linear Regression. Attributes with a "-99999" value represent a null value. DSAS -99999 -99999 LRR Linear Regression Rate. Attributes with a "-99999" value represent a null value. DSAS -99999 1.65 SHAPE_Leng Length of feature in internal units. ESRI 4999.999967 5000.000003 U.S. Geological Survey James Flocks mailing and physical

600 4th Street South

St. Petersburg Florida 33701 US (727) 502-8012 (727) 502-8001 Monday through Friday, 9:00 a.m. to 5:00 p.m., Eastern Standard Time All of this report is available online. Breton_Transects_with_Rates_Pre_1950s.shp 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. ArcGIS shapefile Shapefile containing transects with historical long-term (Pre-1950s) shoreline change statistics for Breton Island, LA. http://coastal.er.usgs.gov/data-release/doi-F7XS5SGM/data/shapefiles/transects.zip None 20201013 U.S. Geological Survey Joseph Terrano mailing and physical

600 4th Street South

St. Petersburg Florida 33701 US (727) 502-8047 (727) 502-8001 jterrano@usgs.gov Monday through Friday, 9:00 a.m. to 5:00 p.m., Eastern Standard Time FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 local time Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. The U.S. Geological Survey requests to be acknowledged as originator of the data in future products or derivative research.