U.S. Geological Survey 20210831 1.0 vector digital data data release doi:10.5066/P9YGIYFX Woods Hole Coastal and Marine Science Center, Woods Hole, MA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.5066/P9YGIYFX https://www.sciencebase.gov/catalog/item/61083d5ad34ef8d70565bfee Marie K. Bartlett Rachel E. Henderson Amy S. Farris Emily A. Himmelstoss 2021 1.0 vector digital data data release doi:10.5066/P9YGIYFX Reston, VA U.S. Geological Survey suggested citation: 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 https://www.sciencebase.gov/catalog/item/60ff22dad34e3ccd830d62aa https://doi.org/10.5066/P9YGIYFX The Massachusetts Office of Coastal Zone Management launched the Shoreline Change Project in 1989 to identify erosion-prone areas of the coast and support local land-use decisions. Trends of shoreline position over long and short-term timescales provide information to landowners, managers, and potential buyers about possible future impacts to coastal resources and infrastructure. In 2001, a 1994 shoreline was added to calculate both long- and short-term shoreline change rates along ocean-facing sections of the Massachusetts coast. In 2013 two oceanfront shorelines for Massachusetts were added using 2008-2009 color aerial orthoimagery and 2007 topographic lidar datasets obtained from NOAA's Ocean Service, Coastal Services Center. In 2018, two new mean high water (MHW) shorelines for the Massachusetts coast extracted from lidar data between 2010-2014 were added to the dataset. This 2021 data release includes rates that incorporate one new shoreline from lidar data extracted in 2018 by the U.S. Army Corps of Engineers (USACE) Joint Airborne Lidar Bathymetry Technical Center of Expertise (JALBTCX), added to the existing database of all historical shorelines (1844-2014), for the North Shore, South Shore, Cape Cod Bay, Outer Cape, Buzzard’s Bay, South Cape, Nantucket, and Martha’s Vineyard. 2018 lidar data did not cover the Boston or Elizabeth Islands regions. Included in this data release is a proxy-datum bias reference line that accounts for the positional difference in a proxy shoreline (the high water Line shoreline) and a datum shoreline (the mean high water shoreline. This issue is explained further in Ruggiero and List (2009) and in the process steps of the metadata associated with the rates. This release includes both long-term (~150+ years) and short term (~30 years) rates. Files associated with the long-term rates have “LT” in their names, files associated with short-term rates have "ST” in their names. This dataset consists of point data which are created by the Digital Shoreline Analysis System (DSAS) version v5.1 at the intersection of shoreline and transect locations. Rate calculations were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 5.1, an ArcGIS extension developed by the U.S. Geological Survey. Measurement transects are cast by DSAS from the baseline to intersect shoreline vectors, and the intersect data provide location and time information used to calculate rates of change. These point data contain identification information related to the DSAS transect (TransectID, TransOrder) as well as the shoreline (ShorelineID, Uncertainty) and proxy-datum bias data (if applicable). 2021 publication date Complete None planned -70.991088 -70.590719 42.892188 42.343857 ISO 19115 Topic Category oceans environment geoscientificInformation None Intersects Shoreline Shoreline Change Digital Shoreline Analysis System DSAS U.S. Geological Survey USGS Coastal and Marine Geology Program CMGP Woods Hole Coastal and Marine Science Center WHCMSC USGS Thesaurus geospatial datasets coastal processes USGS Metadata Identifier USGS:61083d5ad34ef8d70565bfee None Atlantic Coast United States North America Massachusetts Boston North Shore None. These data were automatically generated using the DSAS v5.1 software application. Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset. These data are not to be used for navigation. U.S. Geological Survey Marie K. Bartlett mailing and physical

384 Woods Hole Road

Woods Hole MA 02543-1598 USA 508-548-8700 x 2306 508-457-2310 mbartlett@usgs.gov https://www.sciencebase.gov/catalog/file/get/61083d5ad34ef8d70565bfee?name=NorthShore_intersects_browse.PNG Map view of data png Microsoft Windows 10 Version 6.2 (Build 1909) Esri ArcGIS 10.7.1.11595 Emily A. Himmelstoss Amy S. Farris Rachel E. Henderson Meredith G. Kratzmann Ayhan Ergul Ouya Zhang Jessica L. Zichichi 2018 1 publication software release version 5.0 Reston, VA U.S. Geological Survey https://code.usgs.gov/cch/dsas/ https://doi.org/10.5066/P9VW42I0 https://woodshole.er.usgs.gov/project-pages/DSAS/ Emily A. Himmelstoss Rachel E. Henderson Meredith G. Kratzmann Amy S. Farris 2018 publication Open-File Report 2018-1179 Reston, VA U.S. Geological Survey Suggested citation: Himmelstoss, E.A., Henderson, R.E., Kratzmann, M, Farris, A., 2018, DSAS version 5.0 user guide. U.S. Geological Survey report 2018-1179, https://doi.org/10.3133/ofr20181179 https://doi.org/10.3133/ofr20181179 https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas Emily A. Himmelstoss Amy S. Farris Kathryn M. Weber 2018 DOI:10.5066/P9O7S72B data release DOI:10.5066/P9O7S72B Reston, VA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.5066/P9O7S72B https://www.sciencebase.gov/catalog/item/5bcde5dce4b0f0758fc178d0 https://www.sciencebase.gov/catalog/file/get/5bcde5dce4b0f0758fc178d0 Peter Ruggiero Jeffrey H. List 200909 publication Journal of Coastal Research vol. 255 n/a Coastal Education and Research Foundation ppg. 1069-1081 https://doi.org/10.2112/08-1051.1 Emily A. Himmelstoss Amy S. Farris Kathryn M. Weber 2019 1 publication Data release DOI:10.5066/P9RRBEYK Reston, VA U.S. Geological Survey https://doi.org/10.5066/P9RRBEYK https://www.sciencebase.gov/catalog/item/5be5857ce4b0b3fc5cf8c6ca The attributes of this dataset are based on the field requirements of the Digital Shoreline Analysis System and were automatically generated by the software during the generation of the intersects layer. These data were generated using DSAS, an automated software program, which does not perform checks for fidelity of the input features. Following generation of the rates and intersects by the DSAS software a visual inspection of the intersects was performed in map view to determine that no unwanted measurements were included in the desired (long- or short-term) shoreline change analysis. This dataset contains all the shoreline/transect intersects used to compute rates in the DSAS v5.1 software application. The intersection points represent the location where transects cast by the Digital Shoreline Analysis System (DSAS) software crosses a historical shoreline position. They can be used to visually display which shorelines were used in the rate calculations and capture details on the shoreline represented by the intersection. The distances between the reference baseline and each shoreline intersection along a transect are used by the DSAS software to compute the shoreline change metrics. The positional uncertainties associated with the shoreline and intersection points are captured in the shoreline attribute table. Marie K. Bartlett Amy S. Farris Kathryn M. Weber Emily A. Himmelstoss 2021 1 vector digital data data release doi:10.5066/P9O8QA8N Reston, VA U.S. Geological Survey Suggested citation: Bartlett, M.K., Farris, A.S., and Weber, K.M., Himmelstoss, E.A., 2021, Massachusetts shoreline change project—A GIS compilation of vector shorelines (1844-2018): U.S. Geological Survey data release https://doi.org/10.5066/P9O8QA8N vector digital data 1844 2018 ground condition MA 1844 - 2018 Shorelines Shorelines published as part of the Massachusetts Shoreline Change Project, 2021 Update were compiled for shoreline change analysis with DSAS v5.1 Marie K. Bartlett Rachel E. Henderson Amy S. Farris Emily A. Himmelstoss 2021 1 vector digital data data release product doi:10.5066/P9YGIYFX Reston, VA U.S. Geological Survey https://doi.org/10.5066/P9YGIYFX vector digital data 2021 ground condition NorthShore_baseline Baseline files for region published as part of the Massachusetts Shoreline Change Project, 2021 Update used for shoreline change analysis with DSAS v5.1 Explanation of the methods used to calculate shoreline change rates as part of the 2021 update for the Massachusetts Office of Coastal Zone Management Shoreline Change Project: This data release consists of intersect point shapefiles that hold the data necessary to calculate long- and short-term rates of shoreline change. Depending on the available data, the shorelines used for analysis may include those referenced to mean high water (MHW) or a proxy-based high water line (HWL).Transects with both MHW and HWL shorelines will have the proxy-datum bias applied. Shoreline data from the 2021 data release (historical and 2018), were merged into a single feature class (MA_shorelines_LT) for the long-term shoreline change. For this completed shoreline compilation, shoreline data were extracted for the last 30 years and merged into a feature class (MA_shorelines_ST) to calculate short-term shoreline change. All files were projected to UTM zone 19N coordinates and confirmed to have the same attribute names needed for use in DSAS. Note the range of shoreline dates will vary by location. Please check the intersect file attributes for a record of the exact dates used. This process step and all subsequent process steps were performed by the same person: Marie K. Bartlett MA 1844 - 2018 Shorelines 2020 MA_shorelines_LT MA_shorelines_ST Marie K. Bartlett U.S. Geological Survey Geologist mailing and physical

384 Woods Hole Road

Woods Hole MA 02543 USA 508-548-8700 x2306 mbartlett@usgs.gov Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= NorthShore_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=300 meters, land direction=left, shoreline intersection=seaward, File produced = NorthShore_transects_LT. For additional details on these parameters, please see the DSAS help file distributed with the DSAS software, or visit the USGS website at: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas. Some transects were manually edited for length, moved, or deleted in an edit session using standard editing tools in ArcMap v10.7.1 MA_shorelines_LT NorthShore_baseline 2020 NorthShore_transects_LT Shoreline intersects and rate calculations performed for long-term rates with and without bias. Parameters Used: shoreline layer= MA_shorelines_LT, shoreline date field=Date_, shoreline uncertainty field name=Uncy, the default accuracy=10 meters, shoreline intersection=seaward, stats calculations=[SCE, NSM, LRR], shoreline threshold=3, confidence interval=90%. Files produced = NorthShore_transects_LT_rates_20210114_154630, NorthShore_transects_LT_intersect_20210114_154630. NOTE: All shorelines have an uncertainty value listed in the attribute table that provides the horizontal uncertainty associated with the shoreline, regardless of the method used. The shoreline database contains both MHW and HWL shorelines thus a proxy-datum bias (PDB), stored as a line feature class appended to the reference baseline, is applied during rate calculation. For more information about the origin of the proxy-datum bias, see Ruggiero and List (2009). Rate statistics are presented with both the PDB applied, and with the bias omitted, in which case the attribute field will show “NB_” or “No bias”. The bias uncertainty values are stored within the bias feature attribute table. MA_shorelines_LT NorthShore_transects_LT 2021 NorthShore_trans_rates_LT NorthShore_intersects_LT Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= NorthShore_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=300 meters, land direction=left, shoreline intersection=seaward, File produced = NorthShore_transects_ST. For additional details on these parameters, please see the DSAS help file distributed with the DSAS software, or visit the USGS website at: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas Some transects were manually edited for length, moved, or deleted in an edit session using standard editing tools in ArcMap v10.7.1. MA_shorelines_ST NorthShore_baseline 2021 NorthShore_transects_ST Shoreline intersects and rate calculations performed for long-term rates with and without bias. Parameters Used: shoreline layer= MA_shorelines_ST, shoreline date field=Date_, shoreline uncertainty field name=Uncy, the default accuracy=5.1 meters, shoreline intersection=seaward, stats calculations=[SCE, NSM, EPR LRR], shoreline threshold=2, confidence interval=90%. Files produced = NorthShore_transects_ST_rates_20210115_102601, NorthShore_transects_ST_intersect_20210115_102601. NOTE: All shorelines have an uncertainty value listed in the attribute table that provides the horizontal uncertainty associated with the shoreline, regardless of the method used. The shoreline database contains both MHW and HWL shorelines thus a proxy-datum bias (PDB), stored as a line feature class appended to the reference baseline, is applied during rate calculation. For more information about the origin of the proxy-datum bias, see Ruggiero and List (2009). Rate statistics are presented with both the PDB applied, and with the bias omitted, in which case the attribute field will show “NB_” or “No bias”. The bias uncertainty values are stored within the bias feature attribute table. MA_shorelines_ST NorthShore_transects_ST 2021 NorthShore_trans_rates_ST NorthShore_intersects_ST The intersect feature classes were exported to shapefiles in ArcMap v10.7.1 by right-clicking the transect layer > Data > Export data. 2021 The exported intersect shapefiles were projected in Esri's ArcToolbox (v10.7.1) > Data Management Tools > Projections and Transformations > Project. Parameters: input projection = UTM zone 19N (WGS84); output projection = geographic coordinates (WGS84); transformation = none. NorthShore_intersects_LT NorthShore_intersects_ST 2021 NorthShore_intersects_LT NorthShore_intersects_ST The metadata title was modified to move the location name to the beginning of the title to account for the alphabetical listing of the individual records when ScienceBase migrates the data release to a new platform and "flattens" the data release structure (20260302). 20260302 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 0.0197369329 0.0266895704 Decimal seconds WGS_1984 WGS_1984 6378137.000000 298.257224 NorthShore_intersects_LT.shp The intersection points are generated by DSAS where each DSAS generated transect crosses a shoreline. These intersections represent the shoreline position, and contain the data necessary for DSAS to compute long-term rates, with and without the proxy-datum bias. Point Object Count: 27231 USGS FID Internal feature number used as a unique identifier of an object within a table primarily used in shapefiles. ESRI Sequential unique whole numbers that are automatically generated. Shape The geometry field (shape) is automatically created and maintained by ArcGIS. It provides a definition of the feature type (point, line, polygon). ESRI Coordinates defining the features. TransectID The TransectID relates directly to the original transect file Object Identifier, ObjectID or OID USGS 1 unlimited TransOrder Assigned by DSAS based on ordering of transects along the baseline. Used to allow user to sort transect data along the baseline from baseline start to baseline end. USGS 0 unlimited BaselineID Values in this field correlate to the baseline attribute field ID and are assigned by DSAS to identify the baseline segment used to generate the measurement transect. Baseline segments assigned an ID = 0 are ignored by DSAS and no transects will be cast along those line segments. USGS 1 unlimited ShorelineI Date of shoreline position; date of survey as determined from shoreline layer. USGS Date of the shoreline in mm/dd/yyyy Distance The distance in meters between the DSAS reference baseline and the shoreline intersection point along a DSAS transect. USGS Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. IntersectX The X-coordinate location in eastings of the intersect point in WGS84 UTM19N. USGS 336151.871584 369584.298973 IntersectY The Y-coordinate location in northings of the intersect point in WGS84 UTM19N. USGS 4689803.276330 4750434.738610 Uncertaint The uncertainty of the shoreline intersect point as defined by the positional-uncertainty value (DSAS_uncy) of the shoreline (ShorelineID). USGS 0 unlimited Bias_Dista The distance in meters between the DSAS reference baseline and the shoreline intersection point along a DSAS transect with the proxy-datum bias applied. May be positive or negative depending on the orientation of the baseline. USGS -277.499268 266.371492 BIAS The estimated unidirectional horizontal offset between the MHW elevation of the lidar data and the HWL shoreline position. USGS 0 unlimited BIAS_X The X-coordinate location of the intersect point with the bias applied. USGS 336159.411428 369584.299939 BIAS_Y The Y-coordinate location of the intersect point with the bias applied. USGS 4689803.275390 4750432.425270 Bias_Uncer This is an estimate of the uncertainty of the bias corrected shoreline. It is the shoreline uncertainty and the bias uncertainty added in quadrature USGS 0 unlimited NorthShore_intersects_ST.shp The intersection points are generated by DSAS where each DSAS generated transect crosses a shoreline. These intersections represent the shoreline position, and contain the data necessary for DSAS to compute short-term rates, with and without the proxy-datum bias. Point Object Count: 18220 USGS FID Internal feature number used as a unique identifier of an object within a table primarily used in shapefiles.. ESRI Sequential unique whole numbers that are automatically generated. Shape The geometry field (shape) is automatically created and maintained by ArcGIS. It provides a definition of the feature type (point, line, polygon). ESRI Coordinates defining the features. TransectID The TransectID relates directly to the original transect file Object Identifier, ObjectID or OID USGS 1 unlimited TransOrder Assigned by DSAS based on ordering of transects along the baseline. Used to allow user to sort transect data along the baseline from baseline start to baseline end. USGS 0 unlimited BaselineID Values in this field correlate to the baseline attribute field ID and are assigned by DSAS to identify the baseline segment used to generate the measurement transect. Baseline segments assigned an ID = 0 are ignored by DSAS and no transects will be cast along those line segments. USGS 1 unlimited ShorelineI Date of shoreline position; date of survey as determined from shoreline layer. USGS Date of the shoreline in mm/dd/yyyy Distance The distance in meters between the DSAS reference baseline and the shoreline intersection point along a DSAS transect. USGS Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. IntersectX The X-coordinate location in eastings of the intersect point in WGS84 UTM19N. USGS 336196.439536 369584.042666 IntersectY The Y-coordinate location in northings of the intersect point in WGS84 UTM19N. USGS 4689817.228640 4748825.508740 Uncertaint The uncertainty of the shoreline intersect point as defined by the positional-uncertainty value (DSAS_uncy) of the shoreline (ShorelineID). USGS 0 unlimited Bias_Dista The distance in meters between the DSAS reference baseline and the shoreline intersection point along a DSAS transect with the proxy-datum bias applied. May be positive or negative depending on the orientation of the baseline. USGS -277.499268 266.371492 BIAS The estimated unidirectional horizontal offset between the MHW elevation of the lidar data and the HWL shoreline position. USGS 0 unlimited BIAS_X The X-coordinate location of the intersect point with the bias applied. USGS 336203.980781 369584.043633 BIAS_Y The Y-coordinate location of the intersect point with the bias applied. USGS 4689817.227690 478825.508740 Bias_Uncer This is an estimate of the uncertainty of the bias corrected shoreline. It is the shoreline uncertainty and the bias uncertainty added in quadrature. USGS 0 unlimited The entity and attribute information provided here describes the tabular data associated with the intersects needed to calculate long-term (greater than 50 years, and typically closer to 100 years) and short-term (approximately 30 years) shoreline change rates. Please review the individual attribute descriptions for detailed information. All calculations for length are in meter units and were based on the UTM zone 19N WGS 84 projection. This region has two shapefiles describing intersects, long-term and short-term. U.S. Geological Survey-ScienceBase U.S. Geological Survey - GS ScienceBase mailing and physical address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov The dataset contains the point intersections used for the analysis of shoreline data, (SHP and other shapefile components), browse graphic, and the FGDC CSDGM metadata in XML format. 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. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), and have been processed successfully on a computer system at the USGS, no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Shapefile ArcGIS 10.7.1 Esri point shapefile These files (.cpg, .dbf, .prj, .sbn, .sbx, .shp, .shp., and .shx) are a collection of files with a common filename prefix and must be downloaded and stored in the same directory. Together they are the components of the shapefile and include FGDC CSDGM-compliant metadata. no compression applied 1 https://www.sciencebase.gov/catalog/file/get/61083d5ad34ef8d70565bfee https://www.sciencebase.gov/catalog/item/61083d5ad34ef8d70565bfee https://doi.org/10.5066/P9YGIYFX The first link downloads all the files on the dataset landing page. The second link is to the dataset landing page where individual files can be viewed and downloaded. The third link is to the data release main landing page. None These data are available in a point shapefile format. The user must have software to read and process the data components of a shapefile. 20260302 Marie K. Bartlett U.S. Geological Survey mailing and physical

384 Woods Hole Road

Woods Hole MA 02543-1598 USA 508-548-8700 x2306 508-547-2310 whsc_data_contact@usgs.gov The metadata contact email address is a generic address in the event the person is no longer with USGS. (updated on 20240319) FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time