Bartlett, M.K., Henderson, R.E., Farris, A.S., and Himmelstoss, E.A., 2021, Massachusetts shoreline change project, 2021 update —A GIS compilation of shoreline change rates calculated using Digital Shoreline Analysis System version 5.1, with supplementary intersects and baselines for Massachusetts: U.S. Geological Survey data release, https://doi.org/10.5066/P9YGIYFX.
Summary
The Digital Shoreline Analysis System (DSAS) is a freely available software application that works within the Environmental Systems Research Institute (ESRI) Geographic Information System (ArcGIS) software. DSAS computes rate-of-change statistics for a time series of shoreline vector data. Additionally, the DSAS application is useful for computing rates of change for any boundary-change problem that incorporates a clearly-identified feature position at discrete times, such as glacier limits, river banks, or land use/cover boundaries. The "bias feature" is a shapefile representation the proxy-datum bias (PDB) data previously published in tabular format (Himmelstoss and others 2010, Himmelstoss and others 2018). These PDB data are used [...]
Summary
The Digital Shoreline Analysis System (DSAS) is a freely available software application that works within the Environmental Systems Research Institute (ESRI) Geographic Information System (ArcGIS) software. DSAS computes rate-of-change statistics for a time series of shoreline vector data. Additionally, the DSAS application is useful for computing rates of change for any boundary-change problem that incorporates a clearly-identified feature position at discrete times, such as glacier limits, river banks, or land use/cover boundaries. The "bias feature" is a shapefile representation the proxy-datum bias (PDB) data previously published in tabular format (Himmelstoss and others 2010, Himmelstoss and others 2018). These PDB data are used to shift older proxy-based shorelines so that they can be directly compared to newer datum-based shorelines and accurate rates can be calculated.
This feature records the proxy-datum bias (PDB) and the uncertainty in the PDB. These data are provided for users of the ArcGIS DSAS extension and should only be used to determine the corrected change rate when both datum based (e.g. MHW) and proxy-based (e.g. HWL) shorelines occur. These data should not be used for any purpose other than that for which they are intended. The United States Geological Survey does not guarantee its validity. Assumptions, analyses, opinions, and actual outcomes may vary. The user should always verify actual data and exercise their own professional judgment when interpreting any outcomes.