Metadata: Identification_Information: Citation: Citation_Information: Originator: Rachel E. Henderson Originator: Meredith G. Kratzmann Publication_Date: 20250922 Title: Shoreline change rates (long-term, 1800s-2010s) for the Long Island Sound coastal region using the Digital Shoreline Analysis System version 5.1 Edition: 1.0 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1TKEDFX Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program Online_Linkage: https://doi.org/10.5066/P1TKEDFX Online_Linkage: https://www.sciencebase.gov/catalog/item/67bfb0c1d34e8876fcbfc9ce Larger_Work_Citation: Citation_Information: Originator: Rachel E. Henderson Originator: Meredith G. Kratzmann Originator: Amy S. Farris Originator: Erika E. Lentz Originator: Emily A. Himmelstoss Publication_Date: 2025 Title: National Shoreline Change—A GIS compilation of vector shorelines and associated shoreline change data from the 1800s to the 2010s for the coast of Long Island Sound, New York and Connecticut Edition: 1.0 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1TKEDFX Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: suggested citation: Henderson, R.E., Kratzmann, M.G., Farris, A.S., Lentz, E.E., and Himmelstoss, E.A., 2025, National Shoreline Change—A GIS compilation of vector shorelines and associated shoreline change data from the 1800s to the 2010s for the coast of Long Island Sound, New York and Connecticut: U.S. Geological Survey data release, https://doi.org/10.5066/P1TKEDFX Online_Linkage: https://doi.org/10.5066/P1TKEDFX Online_Linkage: https://www.sciencebase.gov/catalog/item/67586ac4d34ebb495ab01800 Description: Abstract: The U.S. Geological Survey (USGS) maintains shoreline positions for the United States coasts from various historical sources, such as aerial photographs or topographic surveys, and contemporary sources, such as lidar-point clouds and digital elevation models. Shorelines are compiled in a GIS and analyzed in the USGS Digital Shoreline Analysis System (DSAS) software to calculate rates of change. Keeping a record of historical shoreline positions is an effective method to monitor change over time, enabling scientists to identify areas most susceptible to erosion or accretion. These data can help coastal managers understand which areas of the coast are vulnerable to change. This data release, and other associated products, represents an expansion of the USGS national-scale shoreline database to include Long Island Sound (LIS) covering coastal areas in New York and Connecticut. The shoreline positions and shoreline change rates provide actionable information to homeowners, coastal communities, and managers of public and private properties to improve resiliency for coastal hazards in Long Island Sound. Purpose: Shoreline positions were compiled for Long Island Sound from the late 1800s through 2010s and were used to calculate shoreline change rates using the Digital Shoreline Analysis System (DSAS) software developed by the U.S. Geological Survey. Long-term (NY: 83 years, CT: 133 years) shoreline change rates for the Long Island Sound coastal region are included in this dataset. 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 provide location and time information used to calculate rates of change. Rate calculations were computed using DSAS version 5.1. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2025 Currentness_Reference: publication date Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -73.817326 East_Bounding_Coordinate: -71.861386 North_Bounding_Coordinate: 41.342565 South_Bounding_Coordinate: 40.798362 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: geoscientificInformation Theme_Keyword: environment Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Shoreline Theme_Keyword: Shoreline change rate Theme_Keyword: Long-term shoreline change rate Theme_Keyword: Erosion Theme_Keyword: Accretion Theme_Keyword: Linear Regression Rate Theme_Keyword: LRR Theme_Keyword: End point rate Theme_Keyword: EPR 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 Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: Woods Hole Coastal and Marine Science Center Theme_Keyword: WHCMSC Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: geospatial datasets Theme_Keyword: coastal processes Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:67bfb0c1d34e8876fcbfc9ce Place: Place_Keyword_Thesaurus: None Place_Keyword: Atlantic Coast Place_Keyword: Long Island Sound Place_Keyword: LIS Place_Keyword: United States Place_Keyword: North America Place_Keyword: New York Place_Keyword: Connecticut Place: Place_Keyword_Thesaurus: GNIS Place_Keyword: Long Island Sound Place_Keyword: State of New York Place_Keyword: State of Connecticut Access_Constraints: No access constraints. Please see 'Distribution Information' for details. Use_Constraints: These data are marked with a Creative Commons CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. These data were automatically generated using the DSAS v5.1 software application. Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset. These data are not to be used for navigation. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Rachel E. Henderson Contact_Address: Address_Type: mailing and physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: rehenderson@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: https://www.sciencebase.gov/catalog/file/get/67bfb0c1d34e8876fcbfc9ce?name=LIS_rates_LT.jpg&allowOpen=true Browse_Graphic_File_Description: Long Island Sound long-term shoreline change, yellow markers indicate data extent. Browse_Graphic_File_Type: JPEG Native_Data_Set_Environment: Microsoft Windows 11 Enterprise; Esri ArcGIS Desktop 10.8.2 Cross_Reference: Citation_Information: Originator: Emily A. Himmelstoss Originator: Amy S. Farris Originator: Rachel E. Henderson Originator: Meredith G. Kratzmann Originator: Ayhan Ergul Originator: Ouya Zhang Originator: Jessica L. Zichichi Originator: E. Robert Thieler Publication_Date: 2021 Title: Digital Shoreline Analysis System (version 5.1): U.S. Geological Survey Software Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: software release Issue_Identification: version 5.1 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: Use the first link to access the version of the software used (v5.1). The second link is to the current version of DSAS (v6.0). The third link directs to the DSAS project page. Online_Linkage: https://doi.org/10.5066/P9VW42I0 Online_Linkage: https://code.usgs.gov/cch/dsas/ Online_Linkage: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas Cross_Reference: Citation_Information: Originator: Emily A. Himmelstoss Originator: Rachel E. Henderson Originator: Meredith G. Kratzmann Originator: Amy S. Farris Publication_Date: 2021 Title: Digital Shoreline Analysis System (version 5.1) User Guide Geospatial_Data_Presentation_Form: publication Series_Information: Series_Name: Open-File Report Issue_Identification: 2021-1091 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Other_Citation_Details: Use the first link to access the user guide. The second link directs to the DSAS project page. Online_Linkage: https://doi.org/10.3133/ofr20211091 Online_Linkage: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas 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 to better represent an orthogonal position to the general trend of the shorelines. Completeness_Report: This dataset contains the transects automatically generated by the DSAS software application that were used to calculate long-term shoreline change rates for the region. Additional transects may have been generated but did not meet the required number of shorelines or time period requirements.#### add information about locations (such as Masons Island south of Mystic) where shoreline type was rocky/developed 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. See the attribute definition of each for more information. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Rachel E. Henderson Originator: Meredith G. Kratzmann Publication_Date: 2025 Title: Baseline for the Long Island Sound coastal region generated to calculate shoreline change rates using the Digital Shoreline Analysis System version 5.1 in Henderson, R.E., Kratzmann, M.G., Farris, A.S., Lentz, E.E., and Himmelstoss, E.A., 2025, National Shoreline Change—A GIS compilation of vector shorelines and associated shoreline change data from the 1800s to the 2010s for the coast of Long Island Sound, New York and Connecticut: U.S. Geological Survey data release, https://doi.org/10.5066/P1TKEDFX Edition: 1.0 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1TKEDFX Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program Other_Citation_Details: The first link is to the larger work, the second is to the baseline dataset. Online_Linkage: https://doi.org/10.5066/P1TKEDFX Online_Linkage: https://www.sciencebase.gov/catalog/item/67bfb09cd34e8876fcbfc9cc Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2025 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: LIS_baseline Source_Contribution: Baseline segments (part of this same data release https://doi.org/10.5066/P1TKEDFX) are used by DSAS to cast transects from which shoreline changes can be measured. Source_Information: Source_Citation: Citation_Information: Originator: Rachel E. Henderson Originator: Meredith G. Kratzmann Publication_Date: 2025 Title: Shorelines for the Long Island Sound coastal region used in shoreline change analysis: Connecticut (1883-2016) and New York (1931-2014) in Henderson, R.E., Kratzmann, M.G., Farris, A.S., Lentz, E.E., and Himmelstoss, E.A., 2025, National Shoreline Change—A GIS compilation of vector shorelines and associated shoreline change data from the 1800s to the 2010s for the coast of Long Island Sound, New York and Connecticut: U.S. Geological Survey data release, https://doi.org/10.5066/P1TKEDFX Edition: 1.0 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P1TKEDFX Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program Other_Citation_Details: The first link is to the larger work, the second is to the shorelines dataset. Online_Linkage: https://doi.org/10.5066/P1TKEDFX Online_Linkage: https://www.sciencebase.gov/catalog/item/67bfb060d34e8876fcbfc9c9 Type_of_Source_Media: digital data Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2025 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: LIS_shorelines Source_Contribution: Shoreline data for Long Island Sound (part of this same data release https://doi.org/10.5066/P1TKEDFX). Note the range of shoreline dates will vary by location. Process_Step: Process_Description: Overview of the workflow used to calculate shoreline change rates and intersection points as part of the Long Island Sound (LIS) shoreline change analysis using DSAS v5.1: 1) Transects were created at 50 meter spacing along shore using a manually created baseline, and shorelines compiled for Long Island Sound (see source citations); 2) Transect features and shorelines were used to generate shoreline intersection points and calculate rates of change; 3) Manual edits performed; 4) Data exported to shapefiles and; 5) Data updated to geographic WGS. Unless otherwise noted, process steps were performed by Rachel E. Henderson. Process_Date: 2025 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Rachel E. Henderson Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing and physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: rehenderson@usgs.gov Process_Step: Process_Description: 1) DSAS v5.1 was used to create interim transect features (stored in a personal geodatabase) to calculate long-term shoreline change rates. DSAS input parameters used: shoreline layer = LIS_Shorelines, baseline layer= LIS_Baseline, baseline group field=DSAS_group, transect spacing=50 meters, search distance=300 meters, shoreline intersection=seaward. File produced and saved to personal geodatabase = LIS_Trans_LT. Some transects were manually edited for length, moved, or deleted in an edit session using standard editing tools in ArcMap v10.8. For additional details on these parameters, please see the DSAS User Guide or visit the USGS website at: https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas. Source_Used_Citation_Abbreviation: LIS_baseline Source_Used_Citation_Abbreviation: LIS_shorelines Process_Date: 2025 Source_Produced_Citation_Abbreviation: LIS_Trans_LT Process_Step: Process_Description: 2) To calculate long-term (LT) shoreline change rates, the entire range of shorelines from 1883 to 2016 were utilized with the DSAS-generated transects to create shoreline intersect points and shoreline change calculations stored as rate transects. Depending on the available data, the shorelines used for analysis may include those referenced to the datum-based mean high water (MHW), or a proxy-based feature such as the high water line (HWL). Input parameters used: shoreline layer= LIS_shorelines, shoreline date field=Date_, shoreline uncertainty field name=Uncy, the default accuracy=10 meters, shoreline intersection=seaward, transect layer= LIS_Trans_LT, stats calculations=all, shoreline threshold=0, confidence interval=90%. Files produced and saved to personal geodatabase = LIS_Trans_LT_rates, LIS_Trans_LT_intersects. Source_Used_Citation_Abbreviation: LIS_shorelines Source_Used_Citation_Abbreviation: LIS_Trans_LT Process_Date: 2025 Source_Produced_Citation_Abbreviation: LIS_Trans_LT_intersects Source_Produced_Citation_Abbreviation: LIS_Trans_LT_rates Process_Step: Process_Description: 3) Google Earth and other orthophoto mosaics were used to identify areas of rocky/bedrock coastlines and areas with significant anthropogenic modification. Rate transects and intersects in these areas were removed from the analysis using editing tools in ArcMap, while results in sandy areas were retained. Before exporting data, all null values were converted to the value 9999, as ArcGIS automatically changes Null values to zero values when converting from a feature class to a shapefile, which is problematic when presenting rates of change. Process_Date: 2025 Process_Step: Process_Description: 4) The rate feature class was exported to a shapefile in ArcMap v10.8 by right-clicking the transect layer > data > export data. File renamed LIS_rates_LT. Source_Used_Citation_Abbreviation: LIS_Trans_LT_rates Process_Date: 2025 Source_Produced_Citation_Abbreviation: LIS_rates_LT Process_Step: Process_Description: 5) The exported rate shapefile was projected in ArcGIS Pro v3.5.57366 > Geoprocessing > Data Management Tools > Project. Parameters: input projection - NAD83 UTM zone 18N ; output projection- geographic coordinates (WGS 84); transformation = WGS_1984_(ITRF00)_To_NAD_1983. Process_Date: 2025 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Meredith G. Kratzmann Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing and physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: mkratzmann@contractor.usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 6334 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.0000001 Longitude_Resolution: 0.0000001 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: WGS_1984 Ellipsoid_Name: WGS_1984 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257224 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: LIS_rates_LT.shp Entity_Type_Definition: Transects were automatically generated by DSAS at a 90 degree angle to the user-specified baseline using a smoothing algorithm to maintain roughly parallel transects that are orthogonal with respect to the baseline. These attributes are for long-term rates in Long Island Sound (LIS). 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: Feature type. 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: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 6348 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: 64 Attribute: Attribute_Label: GroupID Attribute_Definition: Optional field to aggregate transects on the basis of physical variations alongshore. The values, 1 (south coast) or 2 (north coast), were pulled from the baseline file Group_ID. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 2 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: 1 Range_Domain_Maximum: 6335 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: 2 Range_Domain_Maximum: 8 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: 200.04 Range_Domain_Maximum: 483735.66 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: SCE Attribute_Definition: The shoreline change envelope (SCE) reports a distance (in meters), not a rate. The SCE value represents the greatest distance among all the shorelines that intersect a given transect. The value for SCE is always positive, as the metric is based on magnitude, not direction. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.08 Range_Domain_Maximum: 300.02 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: NSM Attribute_Definition: The net shoreline movement (NSM) is the distance between the oldest and the youngest shorelines for each transect, therefore, units are in meters. Positive values indicate accretion (seaward movement) and negative values indicate erosion (landward movement). . Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -300.02 Range_Domain_Maximum: 262.31 Attribute_Units_of_Measure: meters per year Attribute: Attribute_Label: EPR Attribute_Definition: The end point rate is calculated by dividing the distance of shoreline movement by the time elapsed between two shorelines, the oldest and most recent only. The rate is reported in meters per year with positive values indicating accretion (seaward movement) and negative values indicating erosion (landward movement). Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -6.25 Range_Domain_Maximum: 3.35 Attribute_Units_of_Measure: meters per year Attribute: Attribute_Label: EPRunc Attribute_Definition: Describes the uncertainty of the reported end point rate in meters. 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. This result is reported as the confidence of the end point rate calculation (EPRunc). Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.09 Range_Domain_Maximum: 1.25 Attribute_Units_of_Measure: meters 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 (seaward movement) and negative values indicating erosion (landward movement). A LRR value of 9999 in the attribute table means that value is Null. This scenario occurs when ShrCount = 2 and there are not enough data points to calculate a linear regression rate. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -2.47 Range_Domain_Maximum: 3.33 Attribute_Units_of_Measure: meters per year Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 9999 Enumerated_Domain_Value_Definition: Null value Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: LR2 Attribute_Definition: The R-squared statistic, or coefficient of determination, is the proportion 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). A LR2 value of 9999 in the attribute table means that LR2 is Null. This scenario occurs when ShrCount = 2 and there are not enough data points to calculate a linear regression rate. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 1 Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 9999 Enumerated_Domain_Value_Definition: Null value Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: LSE Attribute_Definition: This quantity is the standard error of the regression, also known as the standard error of the estimate. To calculate it, the distance between each data point and the regression line is calculated. These distances are squared then summed. The sum is divided by the number of data point minus two. The square root is taken of the result. A LSE value of 9999 in the attribute table means that LSE is Null. This scenario occurs when ShrCount = 2 and there are not enough data points to calculate a linear regression rate. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 104.4 Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 9999 Enumerated_Domain_Value_Definition: Null value Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey 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. An LCI90 value of 9999 in the attribute table means that LCI90 is Null. This scenario occurs when ShrCount = 2 and there are not enough data points to calculate a linear regression rate. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 6.0 Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 9999 Enumerated_Domain_Value_Definition: Null value Enumerated_Domain_Value_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: SHAPE_Leng Attribute_Definition: Length of feature in meter units (UTM zone 18N) Attribute_Definition_Source: Esri Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 52.86836 Range_Domain_Maximum: 276.991923 Attribute_Units_of_Measure: meters Overview_Description: Entity_and_Attribute_Overview: The entity and attribute information provided here describes the tabular data associated with long-term shoreline change rates for Long Island Sound. Please review the individual attribute descriptions for detailed information. All calculations for length are in meter units and were based on the UTM zone 18N NAD83 projection. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - ScienceBase Contact_Address: Address_Type: mailing and physical address Address: Federal Center, Building 810, MS 302 City: Denver State_or_Province: CO Postal_Code: 80225 Country: USA Contact_Voice_Telephone: 1-888-275-8747 Contact_Electronic_Mail_Address: sciencebase@usgs.gov Resource_Description: The dataset contains the polyline rates of shoreline change data, (SHP and other shapefile components), browse graphic, and the FGDC CSDGM metadata. Distribution_Liability: Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (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. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: Shapefile Format_Version_Number: ArcGIS Pro version 3.5.57366 Format_Specification: Esri polyline shapefile (compressed to ZIP format) Format_Information_Content: These files (.cpg, .dbf, .prj, .sbn, .sbx, .shp, .html, 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 in HTML format. Transfer size is in MB. File_Decompression_Technique: Unzip Transfer_Size: 0.53 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P1TKEDFX Network_Resource_Name: https://www.sciencebase.gov/catalog/file/get/67bfb0c1d34e8876fcbfc9ce Network_Resource_Name: https://www.sciencebase.gov/catalog/item/67bfb0c1d34e8876fcbfc9ce Access_Instructions: The first link is to the USGS publication page, the second link downloads all the data on the landing page, and the third link is to the dataset landing page. Fees: None Technical_Prerequisites: These data are available in a polyline shapefile format. The user must have software to read and process the data components of a shapefile. Metadata_Reference_Information: Metadata_Date: 20250922 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Meredith G. Kratzmann Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: whsc_data_contact@usgs.gov Contact_Instructions: The metadata contact email address is a generic address in the event the person is no longer with USGS. Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time