U.S. Geological Survey 20210831 1 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/610a9fcbd34ef8d705689323 Marie K. Bartlett Rachel E. Henderson Amy S. Farris Emily A. Himmelstoss 2021 1 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 extracted from 2018 lidar data collected 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 (like a High Water Line shoreline) and a datum shoreline (like a 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 describes the long-term (~150+ years) and short-term (~30 years) shoreline change rates for the coastal region south of Boston, MA. 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. Long-term and short-term rates of shoreline change were calculated using a linear regression rate based on available shoreline data. A reference baseline was used as the originating point for the orthogonal transects cast by the DSAS software. The transects intersect each shoreline establishing measurement points, which are then used to calculate rates. This dataset consists of shoreline change rates calculated with DSAS v5.1 and stored as a new transect layer. Original 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 2021 ground condition of the most recent shoreline these rates are based on Complete None planned -70.925854 -70.494347 42.310490 41.7779 ISO 19115 Topic Category geoscientificInformation oceans USGS Thesaurus geospatial datasets coastal processes None Esri polyline shapefile Shoreline Historical Shoreline Long-term Short-term Shoreline Change Rate Erosion Accretion Linear Regression Rate LRR Baseline Transect Digital Shoreline Analysis System DSAS U.S. Geological Survey USGS Coastal and Marine Geology Program CMGP Woods Hole Coastal and Marine Science Center WHCMSC Massachusetts Office of Coastal Zone Management USGS Metadata Identifier USGS:610a9fcbd34ef8d705689323 None Massachusetts Atlantic Coast United States New England Boston South Shore None These data were automatically generated using the DSAS v5.1 software applications. 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. Marie K. Bartlett USGS Geologist mailing and physical

384 Woods Hole Rd

Woods Hole MA 02543-1598 USA 508-548-8700 x2306 508-547-2310 mbartlett@usgs.gov https://www.sciencebase.gov/catalog/file/get/610a9fcbd34ef8d705689323?name=SouthShore_rates_browse.PNG Map view of data PNG Microsoft Windows 10 Version 6.2 (Build 1909) Esri ArcGIS 10.7.1.11595 E.A. Himmelstoss A.S. Farris R.E. Henderson M.G. Kratzmann A. Ergul O. Zhang J.L. Zichichi E.R. Thieler 2018 Software release software version 5 Reston, VA U.S. Geological Survey, Coastal and Marine Geology Program Suggested citation: Himmelstoss, E.A., Farris, A.S., Henderson, R.E., Kratzmann, M.G., Ergul, A., Zhang, O., Zichichi, J.L., and Thieler, E.R., 2018, Digital Shoreline Analysis System (ver. 5.0): U.S. Geological Survey software, https://doi.org/10.5066/P9VW42I0 . https://code.usgs.gov/cch/dsas/ https://doi.org/10.5066/P9VW42I0 E.A. Himmelstoss R.E. Henderson M.G. Kratzmann A. Farris 2018 Open-file report Open File Report 2018-1179 Woods Hole, MA U.S. Geological Survey, Coastal and Marine Geology Program 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 E.R. Thieler T.I. Smith Julia Knisel D.W. Sampson 2013 publication Open-File Report 2012-1189 Reston, VA U.S. Geological Survey http://pubs.usgs.gov/of/2012/1189/ Emily A. Himmelstoss Amy S. Farris Kathryn M. Weber 2018 publication Data Release DOI:10.5066/P9O7S72B Reston, VA U.S. Geological Survey 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 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 https://doi.org/10.5066/P9RRBEYK. https://www.sciencebase.gov/catalog/item/5c657589e4b0fe48cb38fc74 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 transect layer or during the calculation of shoreline change rates performed by the software. These data were generated using DSAS v5.1. The transects automatically generated by the software were visually inspected along with the shoreline data prior to rate calculations. Sometimes transect positions were manually edited within a standard ArcMap edit session to adjust the position at which an individual transect intersected the shorelines to better represent an orthogonal position to the general trend of the coast over time. This dataset contains the transects automatically generated by the DSAS software application that were used to calculate shoreline change rates for the region. Additional transects may have been generated but did not intersect the minimum requirement of three shorelines. Shoreline change rates data are provided where there are available shorelines to compute change metrics. The uncertainty of the linear regression rate is estimated by the elements LR2, LSE and LCI90_0. See the attribute definition of each for more information. 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 https://www.sciencebase.gov/catalog/item/60ff09abd34e3ccd830d5dac 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 https://www.sciencebase.gov/catalog/item/60ff22dad34e3ccd830d62aa vector digital data 2021 ground condition SouthShore_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 rate transect files that hold 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. Form 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 corresponding intersect file 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= SouthShore_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=300 meters, land direction=right, shoreline intersection=seaward, File produced = SouthShore_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 SouthShore_baseline 2021 SouthShore_transects_LT Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= SouthShore_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=300 meters, land direction=right, shoreline intersection=seaward, File produced = SouthShore_transects_LT. 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 Therefore 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 SouthShore_transects_LT 2021 SouthShore_trans_rates_LT SouthShore_intersects_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 = SouthShore_trans_LT_rates_20210608_151813, SouthShore_trans_LT_intersect_20210608_151813. 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 SouthShore_baseline 2021 SouthShore_transects_ST Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= SouthShore_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=300 meters, land direction=right, shoreline intersection=seaward, File produced = SouthShore_trans_ST. 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 SouthShore_transects_ST 2021 SouthShore_trans_rates_ST SouthShore_intersects_ST The rate feature classes were exported to shapefiles in ArcMap v10.7.1 by right-clicking the transect layer > Data > Export data. 2021 The exported rate 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. SouthShore_trans_rates_LT SouthShore_trans_rates_ST 2021 SouthShore_rates_LT SouthShore_rates_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 0.0197394690 0.0264524065 Decimal seconds D WGS 1984 WGS 1984 6378137.0 298.257223563 SouthShore_rates_LT.shp Rates of long-term shoreline change are calculated by DSAS and stored in the transect file, using the distance measurements between shorelines and baseline at each DSAS transect. These attributes are for long-term rates with and without bias applied. The shapefiles will have LT for long-term in filename. Vector Object Count: 3406 U.S. Geological Survey 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 Feature geometry Esri Coordinates defining the features. TransectID A unique identification number for each transect. Values may not increment sequentially alongshore. U.S. Geological Survey Sequential unique whole numbers that are automatically generated. BaselineID Unique identification number of the baseline segment. If BaselineID=0 no transects will be generated. Used by DSAS to determine transect ordering alongshore if multiple baseline segments exist. U.S. Geological Survey 1 unlimited GroupID This optional field is a way to aggregate transects on the basis of physical variations alongshore (for example, tidal inlets, change in coastal type, or hard stabilization features). This value was assigned by the user as an attribute to a baseline segment and results in a group average being reported in the DSAS summary text file. U.S. Geological Survey 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. U.S. Geological Survey 0 unlimited Azimuth Assigned by DSAS to record the azimuth of the transect measure in degrees clockwise from North. If a transect position has been adjusted during the editing process, the azimuth value in the attribute table is updated automatically. U.S. Geological Survey 0 360 Degrees ShrCount Number of shorelines used to compute shoreline change metrics. U.S. Geological Survey 3 unlimited TCD The Total Cumulative Distance (TCD) is the measure in meters along shore from the start of the baseline segment with an ID=1, and measured sequentially alongshore to the end of the final baseline segment U.S. Geological Survey 0 unlimited SHAPE_Length Length of feature in meter units (UTM zone 19N, WGS 84) Esri 0 unlimited LRR A linear regression rate-of-change statistic was calculated by fitting a least-squares regression line to all shoreline points for a particular transect. Any shoreline points that are referenced to HWL were adjusted by the proxy-datum bias distance (meters) along the transect to correct for the offset between proxy-based HWL and datum-based MHW shorelines. The best-fit regression line is placed so that the sum of the squared residuals (determined by squaring the offset distance of each data point from the regression line and adding the squared residuals together) is minimized. The linear regression rate is the slope of the line. The rate is reported in meters per year with positive values indicating accretion and negative values indicating erosion. LRR calculations require a minimum of 3 shorelines; less than 3 shorelines results in a “null” value, which is not a supported value in shapefile format . A value of 9999 in the LRR attribute field along with a ShRCount of 2 indicates the required number of shorelines to compute the linear regression rate was not met. U.S. Geological Survey Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. Reported in meters per year. NB_LRR The LRR without the bias applied. U.S. Geological Survey Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. Reported in meters per year. LR2 The R-squared statistic, or coefficient of determination, is the percentage of variance in the data that is explained by a regression. It is a dimensionless index that ranges from 1.0 to 0.0 and measures how successfully the best-fit line accounts for variation in the data. The smaller the variability of the residual values around the regression line relative to the overall variability, the better the prediction (and closer the R-squared value is to 1.0). U.S. Geological Survey 0 1 NB_LR2 The LR2 without the bias applied. U.S. Geological Survey 0 1 LSE The predicted (or estimated) values of y (the distance from baseline in meters) are computed for each shoreline point by using the values of x (the shoreline date) and solving the equation for the best-fit regression line (y=mx+b). The standard error is also called the standard deviation. U.S. Geological Survey Positive decimal values in meters. NB_LSE The LSE without the bias applied. U.S. Geological Survey Positive decimal values in meters. LCI90 The standard error of the slope with confidence interval describes the uncertainty of the reported rate. The LRR rates are determined by a best-fit regression line for the shoreline data at each transect. The slope of this line is the reported rate of change (in meters/year). The confidence interval (LCI) is calculated by multiplying the standard error (also called the standard deviation) of the slope by the two-tailed test statistic at the user-specified 90 percent confidence. This value is often reported in conjunction with the slope to describe the confidence of the reported rate. For example: LRR = 1.2 LCI90 = 0.7 could be reported as a rate of 1.2 (+/-) 0.7 meters/year. U.S. Geological Survey Positive decimal values in meters NB_LCI90 The LCI at the user-selected confidence value without the bias applied. U.S. Geological Survey Positive decimal values in meters SouthShore_rates_ST.shp Rates of short-term shoreline change are calculated by DSAS and stored in the transect file, using the distance measurements between shorelines and baseline at each DSAS transect. These attributes are for short-term rates with and without bias applied. The shapefiles will have ST for short-term in filename. Vector object count: 3390 U.S. Geological Survey 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 Feature geometry. ESRI Coordinates defining the features. TransectID A unique identification number for each transect. Values may not increment sequentially alongshore. USGS Sequential unique whole numbers that are automatically generated. BaselineID Unique identification number of the baseline segment. If BaselineID=0 no transects will be generated. Used by DSAS to determine transect ordering alongshore if multiple baseline segments exist. USGS 1 unlimited GroupID This optional field is a way to aggregate transects on the basis of physical variations alongshore (for example, tidal inlets, change in coastal type, or hard stabilization features). This value was assigned by the user as an attribute to a baseline segment and results in a group average being reported in the DSAS summary text file. 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 Azimuth Assigned by DSAS to record the azimuth of the transect measure in degrees clockwise from North. If a transect position has been adjusted during the editing process, the azimuth value in the attribute table is updated automatically. USGS 0 360 ShrCount Number of shorelines used to compute shoreline change metrics. USGS 2 unlimited TCD The Total Cumulative Distance (TCD) is the measure in meters along shore from the start of the baseline segment with an ID=1, and measured sequentially alongshore to the end of the final baseline segment USGS 0 unlimited EPR The end point rate (EPR) is calculated by determining the distance between the oldest and youngest shoreline on a DSAS transect and dividing by the time elapsed between the two shoreline dates. U.S. Geological Survey Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. Reported in meters per year. NB_EPR EPR without the bias applied. U.S. Geological Survey Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. Reported in meters per year. EPRunc An estimate of end point rate uncertainty. The shoreline uncertainties for the two positions used in the end point calculation are each squared, then added together (summation of squares). The square root of the summation of squares is divided by the number of years between the two shorelines. U.S. Geological Survey 0 unlimited NB_EPRunc EPRunc without the bias applied. U.S. Geological Survey 0 unlimited LRR A linear regression rate-of-change statistic was calculated by fitting a least-squares regression line to all shoreline points for a particular transect. Any shoreline points that are referenced to HWL were adjusted by the proxy-datum bias distance (meters) along the transect to correct for the offset between proxy-based HWL and datum-based MHW shorelines. The best-fit regression line is placed so that the sum of the squared residuals (determined by squaring the offset distance of each data point from the regression line and adding the squared residuals together) is minimized. The linear regression rate is the slope of the line. The rate is reported in meters per year with positive values indicating accretion and negative values indicating erosion. LRR calculations require a minimum of 3 shorelines; less than 3 shorelines results in a “null” value, which is not a supported value in shapefile format . A value of 9999 in the LRR attribute field along with a ShRCount of 2 indicates the required number of shorelines to compute the linear regression rate was not met. USGS Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. Reported in meters per year. NB_LRR LRR without the bias applied. USGS Decimal values may be positive or negative, which is used to indicate landward (negative) or seaward (positive) direction from baseline origin. Reported in meters per year. LR2 The R-squared statistic, or coefficient of determination, is the percentage of variance in the data that is explained by a regression. It is a dimensionless index that ranges from 1.0 to 0.0 and measures how successfully the best-fit line accounts for variation in the data. The smaller the variability of the residual values around the regression line relative to the overall variability, the better the prediction (and closer the R-squared value is to 1.0). USGS 0 1 NB_LR2 LR2 without the bias applied USGS 0 1 LSE The predicted (or estimated) values of y (the distance from baseline in meters) are computed for each shoreline point by using the values of x (the shoreline date) and solving the equation for the best-fit regression line (y=mx+b). The standard error is also called the standard deviation. USGS Positive decimal values in meters. NB_LSE LSE without the bias applied. USGS Positive decimal values in meters. LCI90 The standard error of the slope with confidence interval describes the uncertainty of the reported rate. The LRR rates are determined by a best-fit regression line for the shoreline data at each transect. The slope of this line is the reported rate of change (in meters/year). The confidence interval (LCI) is calculated by multiplying the standard error (also called the standard deviation) of the slope by the two-tailed test statistic at the user-specified 90 percent confidence. This value is often reported in conjunction with the slope to describe the confidence of the reported rate. For example: LRR = 1.2 LCI90 = 0.7 could be reported as a rate of 1.2 (+/-) 0.7 meters/year. USGS Positive decimal values in meters. NB_LCI90 LC190 without the bias applied. USGS Positive decimal values in meters. SHAPE_Leng Length of feature in meter units (UTM zone 19N, WGS 84) USGS 0 unlimited The entity and attribute information provided here describes the tabular data associated with long-term (greater than 50 years, and typically closer to 100 years) and short-term (approximately 30 years) shoreline change rates. Rate statistics are presented with and without the proxy-datum bias, distinguished by fields containing “NB_” for “no bias” in the attribute table. 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 rates, long-term (150+ years) and short-term (~30 years). U.S. Geological Survey - ScienceBase U.S. Geological Survey - ScienceBase mailing and physical

Federal Center, Building 810, MS 302

Denver CO 88025 1-888-275-8747 sciencebase@usgs.gov The dataset contains the rate transect features used to store shoreline change 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/610a9fcbd34ef8d705689323 https://www.sciencebase.gov/catalog/item/610a9fcbd34ef8d705689323 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 U.S. Geological Survey Marie Bartlett Geologist mailing and physical

384 Woods Hole Rd

Woods Hole MA 02543-1598 USA 508-548-8700 x2306 508-457-2310 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 Standard for Digital Geospatial Metadata FGDC-STD-001-1998 local time