|Range of values|
|1||The baseline segment is positioned offshore or seaward of the input shorelines.|
|0||The baseline segment is positioned onshore or landward of the input shorelines.|
|0||Transects will be cast to the left of the baseline based on directionality from the start vertex of the baseline segment to the last vertex that the ends line segment.|
|1||Transects will be cast to the right of the baseline based on directionality from the start vertex of the baseline segment to the last vertex that ends the line segment.|
Rates of long-term and short-term shoreline change were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 4.3, an ArcGIS extension developed by the U.S. Geological Survey. The baseline is used as a reference line for the transects cast by the DSAS software. The transects intersect each shoreline at the measurement points, which are then used to calculate shoreline-change rates for the Massachusetts Office of Coastal Zone Management Shoreline Change Project.
Are there legal restrictions on access or use of the data?
Use_Constraints:Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey and the Massachusetts Office of Coastal Zone Management as the originators of this dataset.
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.
|Data format:||This WinZip (version 16.5) file contains a shapefile which includes the offshore/onshore baseline for generating shore-normal transects in DSAS. The metadata is also included. in format Shapefile (version ArcGIS 10) Esri polyline shapefile Size: 1|
This zip file contains data available in Environmental Systems Research Institute (Esri) polyline shapefile format. The user must have ArcGIS or ArcView 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing the data. A free data viewer, ArcExplorer, capable of displaying the data is available from Esri at www.esri.com.