Metadata: Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 20210831 Title: Long-term and short-term shoreline change rates for the region of Martha's Vineyard, Massachusetts, calculated with and without the proxy-datum bias using the Digital Shoreline Analysis System version 5.1 Edition: 1 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: Data release Issue_Identification: doi:10.5066/P9YGIYFX Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Online_Linkage: https://doi.org/10.5066/P9YGIYFX Online_Linkage: https://www.sciencebase.gov/catalog/item/610829f2d34ef8d70565ba19 Larger_Work_Citation: Citation_Information: Originator: Marie K. Bartlett Originator: Rachel E. Henderson Originator: Amy S. Farris Originator: Emily A. Himmelstoss Publication_Date: 2021 Title: 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 Edition: 1 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: Data release Issue_Identification: doi:10.5066/P9YGIYFX Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: 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 Online_Linkage: https://www.sciencebase.gov/catalog/item/60ff22dad34e3ccd830d62aa Online_Linkage: https://doi.org/10.5066/P9YGIYFX Description: Abstract: 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. Purpose: This dataset describes the long-term (~150+ years) and short-term (~30 years) shoreline change rates for the Martha's Vineyard, MA coastal region. 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 Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2021 Currentness_Reference: ground condition of the most recent shoreline these rates are based on Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -70.8390 East_Bounding_Coordinate: -70.4463 North_Bounding_Coordinate: 41.4827 South_Bounding_Coordinate: 41.2490 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: oceans Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: geospatial datasets Theme_Keyword: coastal processes Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Esri polyline shapefile Theme_Keyword: Shoreline Theme_Keyword: Historical Shoreline Theme_Keyword: Long-term Theme_Keyword: Short-term Theme_Keyword: Shoreline Change Rate Theme_Keyword: Erosion Theme_Keyword: Accretion Theme_Keyword: Linear Regression Rate Theme_Keyword: LRR Theme_Keyword: Baseline Theme_Keyword: Transect Theme_Keyword: Digital Shoreline Analysis System Theme_Keyword: DSAS Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: CMGP Theme_Keyword: Woods Hole Coastal and Marine Science Center Theme_Keyword: WHCMSC Theme_Keyword: Massachusetts Office of Coastal Zone Management Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:610829f2d34ef8d70565ba19 Place: Place_Keyword_Thesaurus: None Place_Keyword: Massachusetts Place_Keyword: Atlantic Coast Place_Keyword: United States Place_Keyword: New England Place_Keyword: Martha's Vineyard Access_Constraints: None Use_Constraints: 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. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Marie K. Bartlett Contact_Organization: USGS Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical Address: 384 Woods Hole Rd City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 x2306 Contact_Facsimile_Telephone: 508-547-2310 Contact_Electronic_Mail_Address: mbartlett@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: https://www.sciencebase.gov/catalog/file/get/610829f2d34ef8d70565ba19?name=MarthasVineyard_rates_browse.PNG Browse_Graphic_File_Description: Map view of data Browse_Graphic_File_Type: PNG Native_Data_Set_Environment: Microsoft Windows 10 Version 6.2 (Build 1909) Esri ArcGIS 10.7.1.11595 Cross_Reference: Citation_Information: Originator: E.A. Himmelstoss Originator: A.S. Farris Originator: R.E. Henderson Originator: M.G. Kratzmann Originator: A. Ergul Originator: O. Zhang Originator: J.L. Zichichi Originator: E.R. Thieler Publication_Date: 2018 Title: Digital Shoreline Analysis System (version 5): U.S. Geological Survey software Geospatial_Data_Presentation_Form: Software release Series_Information: Series_Name: software Issue_Identification: version 5 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Other_Citation_Details: 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 . Online_Linkage: https://code.usgs.gov/cch/dsas/ Online_Linkage: https://doi.org/10.5066/P9VW42I0 Cross_Reference: Citation_Information: Originator: E.A. Himmelstoss Originator: R.E. Henderson Originator: M.G. Kratzmann Originator: A. Farris Publication_Date: 2018 Title: Digital Shoreline Analysis System (DSAS) Version 5 User Guide Geospatial_Data_Presentation_Form: Open-file report Series_Information: Series_Name: Open File Report Issue_Identification: 2018-1179 Publication_Information: Publication_Place: Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Other_Citation_Details: 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 Online_Linkage: https://doi.org/10.3133/ofr20181179 Online_Linkage: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas Cross_Reference: Citation_Information: Originator: E.R. Thieler Originator: T.I. Smith Originator: Julia Knisel Originator: D.W. Sampson Publication_Date: 2013 Title: Massachusetts Shoreline Change Mapping and Analysis Project, 2012 Update Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: Open-File Report Issue_Identification: 2012-1189 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/of/2012/1189/ Cross_Reference: Citation_Information: Originator: Emily A. Himmelstoss Originator: Amy S. Farris Originator: Kathryn M. Weber Publication_Date: 2018 Title: Massachusetts Shoreline Change Project: A GIS Compilation of Vector Shorelines for the 2018 update Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: Data Release Issue_Identification: DOI:10.5066/P9O7S72B Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9O7S72B Online_Linkage: https://www.sciencebase.gov/catalog/item/5bcde5dce4b0f0758fc178d0 Online_Linkage: https://www.sciencebase.gov/catalog/file/get/5bcde5dce4b0f0758fc178d0 Cross_Reference: Citation_Information: Originator: Peter Ruggiero Originator: Jeffrey H. List Publication_Date: 200909 Title: Improving Accuracy and Statistical Reliability of Shoreline Position and Change Rate Estimates Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: Journal of Coastal Research Issue_Identification: vol. 255 Publication_Information: Publication_Place: n/a Publisher: Coastal Education and Research Foundation Online_Linkage: https://doi.org/10.2112/08-1051.1 Cross_Reference: Citation_Information: Originator: Emily A. Himmelstoss Originator: Amy S. Farris Originator: Kathryn M. Weber Publication_Date: 2019 Title: Massachusetts Shoreline Change Project, 2018 Update: A GIS Compilation of Shoreline Change Rates Calculated Using Digital Shoreline Analysis System Version 5.0, With Supplementary Intersects and Baselines for Massachusetts Edition: 1 Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: Data release Issue_Identification: DOI:10.5066/P9RRBEYK Online_Linkage: https://doi.org/10.5066/P9RRBEYK. Online_Linkage: https://www.sciencebase.gov/catalog/item/5c657589e4b0fe48cb38fc74 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: 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. Logical_Consistency_Report: 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. Completeness_Report: 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. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: 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. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Marie K. Bartlett Originator: Amy S. Farris Originator: Kathryn M. Weber Originator: Emily A. Himmelstoss Publication_Date: 2021 Title: Massachusetts Shoreline Change Project: A GIS Compilation of Vector Shorelines (1844-2018) Edition: 1 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release Issue_Identification: doi:10.5066/P9O8QA8N Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: 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 Online_Linkage: https://doi.org/10.5066/P9O8QA8N Online_Linkage: https://www.sciencebase.gov/catalog/item/60ff09abd34e3ccd830d5dac Type_of_Source_Media: vector digital data Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1844 Ending_Date: 2018 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: MA 1844 - 2018 Shorelines Source_Contribution: Shorelines published as part of the Massachusetts Shoreline Change Project, 2021 Update were compiled for shoreline change analysis with DSAS v5.1 Source_Information: Source_Citation: Citation_Information: Originator: Marie K. Bartlett Originator: Rachel E. Henderson Originator: Amy S. Farris Originator: Emily A. Himmelstoss Publication_Date: 2021 Title: Baseline for the northern coast of Martha's Vineyard, Massachusetts, generated to calculate shoreline change rates using the Digital Shoreline Analysis System version 5.1 Edition: 1 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release product Issue_Identification: doi:10.5066/P9YGIYFX Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9YGIYFX Online_Linkage: https://www.sciencebase.gov/catalog/item/61082f8ed34ef8d70565bbf3 Type_of_Source_Media: vector digital data Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2021 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: MarthasVN_baseline Source_Contribution: Baseline files for region published as part of the Massachusetts Shoreline Change Project, 2021 Update used for shoreline change analysis with DSAS v5.1 Source_Information: Source_Citation: Citation_Information: Originator: Marie K. Bartlett Originator: Rachel E. Henderson Originator: Amy S. Farris Originator: Emily A. Himmelstoss Publication_Date: 2021 Title: Baseline for the southern coast of Martha's Vineyard, Massachusetts, generated to calculate shoreline change rates using the Digital Shoreline Analysis System version 5.1 Edition: 1 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release product Issue_Identification: doi:10.5066/P9YGIYFX Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9YGIYFX Online_Linkage: https://www.sciencebase.gov/catalog/item/610832dfd34ef8d70565bf42 Type_of_Source_Media: vector digital data Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2021 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: MarthasVS_baseline Source_Contribution: Baseline files for region published as part of the Massachusetts Shoreline Change Project, 2021 Update used for shoreline change analysis with DSAS v5.1 Process_Step: Process_Description: 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 Source_Used_Citation_Abbreviation: MA 1844 - 2018 Shorelines Process_Date: 2020 Source_Produced_Citation_Abbreviation: MA_shorelines_LT Source_Produced_Citation_Abbreviation: MA_shorelines_ST Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Marie K. Bartlett Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Country: USA Contact_Voice_Telephone: 508-548-8700 x2306 Contact_Electronic_Mail_Address: mbartlett@usgs.gov Process_Step: Process_Description: Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= MarthasVN_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=200 meters, land direction=left, shoreline intersection=seaward, File produced = MarthasVN_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 Source_Used_Citation_Abbreviation: MA_shorelines_LT Source_Used_Citation_Abbreviation: MarthasVN_baseline Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVN_transects_LT Process_Step: Process_Description: 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 = MarthasVN_trans_LT_rates_20210318_133812, MarthasVN_trans_LT_intersect_20210318_133812. 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. Source_Used_Citation_Abbreviation: MA_shorelines_LT Source_Used_Citation_Abbreviation: MarthasVN_transects_LT Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVN_trans_rates_LT Source_Produced_Citation_Abbreviation: MarthasVN_intersects_LT Process_Step: Process_Description: Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= MarthasVN_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=200 meters, land direction=left, shoreline intersection=seaward, File produced = MarthasVN_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 Source_Used_Citation_Abbreviation: MA_shorelines_ST Source_Used_Citation_Abbreviation: MarthasVN_baseline Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVN_transects_ST Process_Step: Process_Description: 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 = MarthasVN_trans_ST_rates_20210322_151603, MarthasVN_trans_ST_intersect_20210322_151603. 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. Source_Used_Citation_Abbreviation: MA_shorelines_ST Source_Used_Citation_Abbreviation: MarthasVN_transects_ST Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVN_trans_rates_ST Source_Produced_Citation_Abbreviation: MarthasVN_intersects_ST Process_Step: Process_Description: Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= MarthasVS_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=200 meters, land direction=left, shoreline intersection=seaward, File produced = MarthasVS_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 Source_Used_Citation_Abbreviation: MA_shorelines_LT Source_Used_Citation_Abbreviation: MarthasVS_baseline Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVS_transects_LT Process_Step: Process_Description: 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 = MarthasVS_trans_rates_LT_20210702_122450, MarthasVS_trans_LT_intersect_20210702_122450. 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. Source_Used_Citation_Abbreviation: MA_shorelines_LT Source_Used_Citation_Abbreviation: MarthasVS_transects_LT Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVS_trans_rates_LT Source_Produced_Citation_Abbreviation: MarthasVS_intersects_LT Process_Step: Process_Description: Transect features generated in a personal geodatabase using DSAS v5.1.2020.0720.0030. Parameters Used: baseline layer= MarthasVS_baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=200 meters, land direction=left, shoreline intersection=seaward, File produced = MarthasVS_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 Source_Used_Citation_Abbreviation: MA_shorelines_ST Source_Used_Citation_Abbreviation: MarthasVS_baseline Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVS_transects_ST Process_Step: Process_Description: 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 = MarthasVS_trans_rates_ST_20210702_124821, MarthasVS_intersect_ST_20210702_124821. 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. Source_Used_Citation_Abbreviation: MA_shorelines_ST Source_Used_Citation_Abbreviation: MarthasVS_transects_ST Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVS_trans_rates_ST Source_Produced_Citation_Abbreviation: MarthasVS_intersects_ST Process_Step: Process_Description: The rate feature classes were exported to shapefiles in ArcMap v10.7.1 by right-clicking the transect layer > Data > Export data. Process_Date: 2021 Process_Step: Process_Description: 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. Source_Used_Citation_Abbreviation: MarthasVN_trans_rates_LT Source_Used_Citation_Abbreviation: MarthasVN_trans_rates_ST Source_Used_Citation_Abbreviation: MarthasVS_trans_rates_LT Source_Used_Citation_Abbreviation: MarthasVS_trans_rates_ST Process_Date: 2021 Source_Produced_Citation_Abbreviation: MarthasVN_rates_LT Source_Produced_Citation_Abbreviation: MarthasVN_rates_ST Source_Produced_Citation_Abbreviation: MarthasVS_rates_LT Source_Produced_Citation_Abbreviation: MarthasVS_rates_ST Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.0197422351 Longitude_Resolution: 0.0261997981 Geographic_Coordinate_Units: Decimal seconds Geodetic_Model: Horizontal_Datum_Name: D WGS 1984 Ellipsoid_Name: WGS 1984 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: MarthasVN_rates_LT.shp Entity_Type_Definition: 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: 1404 Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number used as a unique identifier of an object within a table primarily used in shapefiles. Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: SHAPE Attribute_Definition: Feature geometry Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Coordinates defining the features. Attribute: Attribute_Label: TransectID Attribute_Definition: A unique identification number for each transect. Values may not increment sequentially alongshore. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: BaselineID Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: GroupID Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TransOrder Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: Azimuth Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 360 Attribute_Units_of_Measure: Degrees Attribute: Attribute_Label: ShrCount Attribute_Definition: Number of shorelines used to compute shoreline change metrics. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 3 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TCD Attribute_Definition: 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 Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: SHAPE_Length Attribute_Definition: Length of feature in meter units (UTM zone 19N, WGS 84) Attribute_Definition_Source: Esri Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: LRR Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: NB_LRR Attribute_Definition: The LRR without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: LR2 Attribute_Definition: 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). Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: NB_LR2 Attribute_Definition: The LR2 without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: LSE Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: NB_LSE Attribute_Definition: The LSE without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: LCI90 Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters Attribute: Attribute_Label: NB_LCI90 Attribute_Definition: The LCI at the user-selected confidence value without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters Detailed_Description: Entity_Type: Entity_Type_Label: MarthasVN_rates_ST.shp Entity_Type_Definition: 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: 1400 Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number used as a unique identifier of an object within a table primarily used in shapefiles. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: Shape Attribute_Definition: Feature geometry. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Coordinates defining the features. Attribute: Attribute_Label: TransectID Attribute_Definition: A unique identification number for each transect. Values may not increment sequentially alongshore. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: BaselineID Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: GroupID Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TransOrder Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: Azimuth Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 360 Attribute: Attribute_Label: ShrCount Attribute_Definition: Number of shorelines used to compute shoreline change metrics. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 2 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TCD Attribute_Definition: 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 Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: EPR Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: NB_EPR Attribute_Definition: EPR without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: EPRunc Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: NB_EPRunc Attribute_Definition: EPRunc without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: LRR Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: NB_LRR Attribute_Definition: LRR without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: LR2 Attribute_Definition: 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). Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: NB_LR2 Attribute_Definition: LR2 without the bias applied Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: LSE Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: NB_LSE Attribute_Definition: LSE without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: LCI90 Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: NB_LCI90 Attribute_Definition: LC190 without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: SHAPE_Leng Attribute_Definition: Length of feature in meter units (UTM zone 19N, WGS 84) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Detailed_Description: Entity_Type: Entity_Type_Label: MarthasVS_rates_LT.shp Entity_Type_Definition: 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 short-term in filename. Vector object count: 1041 Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number used as a unique identifier of an object within a table primarily used in shapefiles. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: Shape Attribute_Definition: Feature geometry. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Coordinates defining the features. Attribute: Attribute_Label: TransectID Attribute_Definition: A unique identification number for each transect. Values may not increment sequentially alongshore. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: BaselineID Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: GroupID Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TransOrder Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: Azimuth Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 360 Attribute: Attribute_Label: ShrCount Attribute_Definition: Number of shorelines used to compute shoreline change metrics. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 2 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TCD Attribute_Definition: 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 Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: LRR Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: NB_LRR Attribute_Definition: LRR without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: LR2 Attribute_Definition: 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). Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: NB_LR2 Attribute_Definition: LR2 without the bias applied Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: LSE Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: NB_LSE Attribute_Definition: LSE without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: LCI90 Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: NB_LCI90 Attribute_Definition: LC190 without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: SHAPE_Leng Attribute_Definition: Length of feature in meter units (UTM zone 19N, WGS 84) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Detailed_Description: Entity_Type: Entity_Type_Label: MarthasVS_rates_ST.shp Entity_Type_Definition: 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: 1041 Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number used as a unique identifier of an object within a table primarily used in shapefiles. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: Shape Attribute_Definition: Feature geometry. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Coordinates defining the features. Attribute: Attribute_Label: TransectID Attribute_Definition: A unique identification number for each transect. Values may not increment sequentially alongshore. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: BaselineID Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: GroupID Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TransOrder Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: Azimuth Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 360 Attribute: Attribute_Label: ShrCount Attribute_Definition: Number of shorelines used to compute shoreline change metrics. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 2 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: TCD Attribute_Definition: 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 Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: EPR Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: NB_EPR Attribute_Definition: EPR without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: EPRunc Attribute_Definition: 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. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: NB_EPRunc Attribute_Definition: EPRunc without the bias applied. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Attribute: Attribute_Label: LRR Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: NB_LRR Attribute_Definition: LRR without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: 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. Attribute: Attribute_Label: LR2 Attribute_Definition: 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). Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: NB_LR2 Attribute_Definition: LR2 without the bias applied Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute: Attribute_Label: LSE Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: NB_LSE Attribute_Definition: LSE without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: LCI90 Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: NB_LCI90 Attribute_Definition: LC190 without the bias applied. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Positive decimal values in meters. Attribute: Attribute_Label: SHAPE_Leng Attribute_Definition: Length of feature in meter units (UTM zone 19N, WGS 84) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: unlimited Overview_Description: Entity_and_Attribute_Overview: 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). Entity_and_Attribute_Detail_Citation: U.S. Geological Survey - ScienceBase Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - ScienceBase Contact_Address: Address_Type: mailing and physical Address: Federal Center, Building 810, MS 302 City: Denver State_or_Province: CO Postal_Code: 88025 Contact_Voice_Telephone: 1-888-275-8747 Contact_Electronic_Mail_Address: sciencebase@usgs.gov Resource_Description: 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. Distribution_Liability: 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 Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: Shapefile Format_Version_Number: ArcGIS 10.7.1 Format_Specification: Esri point shapefile Format_Information_Content: 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. File_Decompression_Technique: no compression applied Transfer_Size: 1 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://www.sciencebase.gov/catalog/file/get/610829f2d34ef8d70565ba19 Network_Resource_Name: https://www.sciencebase.gov/catalog/item/610829f2d34ef8d70565ba19 Network_Resource_Name: https://doi.org/10.5066/P9YGIYFX Access_Instructions: 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. Fees: none Technical_Prerequisites: These data are available in a point shapefile format. The user must have software to read and process the data components of a shapefile. Metadata_Reference_Information: Metadata_Date: 20210831 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Marie Bartlett Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical Address: 384 Woods Hole Rd City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 x2306 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: mbartlett@usgs.gov Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time