Gibbs, Ann E. Ohman, Karin A. Coppersmith, Ryan Richmond, Bruce M. 2017 vector digital data (polyline) data release 10.5066/F72Z13N1 U.S. Geological Survey, Pacific Coastal and Marine Science Center, Santa Cruz and Menlo Park, CA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.5066/F72Z13N1 https://www.sciencebase.gov/catalog/file/get/5949c4e7e4b062508e359c0a Gibbs, Ann E. Ohman, Karin A. Coppersmith, Ryan Richmond, Bruce M. 2017 data release 10.5066/F72Z13N1 Reston, VA U.S. Geological Survey https://doi.org/10.5066/F72Z13N1 This dataset consists of short-term (~31 years) shoreline change rates for the north coast of Alaska between the Hulahula River and the Colville River. Rate calculations were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 4.3, an ArcGIS extension developed by the U.S. Geological Survey. Short-term rates of shoreline change were calculated using a linear regression rate-of-change method based on available shoreline data between 1979 and 2010. 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 short-term rates. The Arctic Coastal Plain of northern Alaska is an area of strategic economic importance to the United States, is home to remote Native American communities, and encompasses unique habitats of global significance. Coastal erosion along the north coast of Alaska is chronic, widespread, may be accelerating, and is threatening defense and energy-related infrastructure, natural shoreline habitats, and Native Alaskan communities. There is an increased demand for accurate information regarding past and present shoreline changes across the United States. To meet these national needs, the Coastal and Marine Geology Program of the U.S. Geological Survey (USGS) is compiling existing reliable historical shoreline data along sandy shores of the conterminous United States and parts of Alaska and Hawaii under the National Assessment of Shoreline Change project. There is no widely accepted standard for analyzing shoreline change. Existing shoreline data measurements and rate calculation methods vary from study to study and prevent combining results into state-wide or regional assessments. The impetus behind the National Assessment project was to develop a standardized method of measuring changes in shoreline position that is consistent from coast to coast. The goal was to facilitate the process of periodically and systematically updating the results in an internally consistent manner. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in Esri format, this metadata file may include some Esri-specific terminology. 1979 2010 ground condition Complete None planned -150.2205141 -144.138743234 70.5174151085 69.9617308591 North coast of Alaska between the Hulahula River and the Colville River USGS Metadata Identifier USGS:5949c4e7e4b062508e359c0a None Shoreline Shoreline Change Digital Shoreline Analysis System DSAS U.S. Geological Survey USGS Coastal and Marine Geology Program CMGP Pacific Coastal and Marine Science Center PCMSC National Assessment of Shoreline Change Project National Assessment of Coastal Change Hazards ISO 19115 Topic Category oceans environment geoscientificInformation USGS Thesaurus coastal processes Data Categories for Marine Planning Habitat Marine Realms Information Bank (MRIB) keywords shoreline accretion shoreline erosion Geographic Names Information System (GNIS) North Slope Beaufort Sea Staines River Sagavanirktok River Colville River Kuparuk River Harrison Bay Prudhoe Bay Arctic National Wildlife Refuge Canning River State of Alaska United States of America None Arctic ANWR None USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. Ann E. Gibbs U.S. Geological Survey, Pacific Coastal and Marine Science Center mailing and physical address

2885 Mission Street

Santa Cruz CA 95060-5792 USA 831-460-7540 831-427-4748 agibbs@usgs.gov CentralBeaufortExtent.jpg Map of the Central Beaufort subregion of the north coast of Alaska shoreline change assessment area. JPEG U.S. Geological Survey Environment as of Metadata Creation: Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.3.1 (Build 4959) Service Pack N/A (Build N/A) Gibbs, A.E. Richmond B.M. 2017 Open-File Report 2017-1107 Reston, VA U.S. Geological Survey https://doi.org/10.3133/ofr20171107 Ann E. Gibbs Bruce M. Richmond 2015 Open-File Report 2015-1048 Reston, VA U.S. Geological Survey https://dx.doi.org/10.3133/ofr20151048 E.R. Thieler E.A. Himmelstoss J.L. Zichichi A. Ergul 2009 Open-File Report 2008-1278 Reston, VA U.S. Geological Survey Current version at time of use was 4.3 https://woodshole.er.usgs.gov/project-pages/DSAS/version4/index.html https://woodshole.er.usgs.gov/project-pages/DSAS/ The attributes of this dataset are based on the field requirements of the Digital Shoreline Analysis System and were automatically generated by the software during the generation of the transect layer or during the calculation of shoreline change rates performed by the software. These data were generated using DSAS v4.3, an automated software program which does not perform checks for fidelity of the input features. The transects were visually inspected and sometimes manually adjusted within a standard ArcMap edit session to adjust the position at which an individual transect intersected the shorelines. This dataset contains the transects automatically generated by the DSAS software application that were used to calculate shoreline change rates along sections of the north coast of Alaska, between the U.S.-Canadian border and Icy Cape, where shoreline position data were available. Additional transects may have been generated but did not intersect the shoreline dates specified. A formal accuracy assessment of the horizontal positional information in the data set has not been conducted. A formal accuracy assessment of the vertical positional information in the data set has either not been conducted, or is not applicable. U.S. Geological Survey 2017 shapefile online U.S. Geological Survey https://www.sciencebase.gov/catalog/file/get/59431667e4b062508e309c41 Digital Resources Unknown ground condition DSAS baseline DSAS baseline used for calculation of shoreline change rates. U.S. Geological Survey 2017 shapefile online U.S. Geological Survey https://www.sciencebase.gov/catalog/file/get/594837a3e4b062508e344435 Digital Resources 1979 2012 ground condition DSAS shoreline DSAS shoreline file used for calculation of shoreline change rates. Transect Features Generated using DSAS v4.3 in ArcMap v10.3. Parameters Used: baseline layer=UTMX_Baseline, transect spacing=50 meters, transect length=500m, cast direction=onshore, baseline location=offshore, cast method=smoothed, smoothing distance=50 meters. For additional details on these parameters, please see the DSAS help file distributed with the DSAS software. 2016 Some transects did not intersect all shorelines at the default transect length. These transects were manually lengthened in an edit session using standard editing tools in ArcMap v10.3. Some transects intersected the shorelines at an oblique angle. These transects were manually adjusted to a more shore-normal position in an edit session using standard editing tools in ArcMap v10.3. 2016 Rate calculations performed using DSAS v4.3 in ArcMap v10.3 on selected shoreline features. Parameters Used: shoreline layer= CentralBeaufort_shorelines, shoreline date field=DATE_, shoreline uncertainty field name=Uncy, the default accuracy= 0 meters, shoreline intersection parameters=nearest, stats calculations=[Linear Regression Rate (LRR)], shoreline threshold=4, confidence interval=90%, 2016 Shoreline change rates table was joined to the transect feature class in ArcMap v10.3 by right-clicking on the transect layer > joins and relates > join > join attributes from a table. Parameters: join field - ObjectID; field in table: TransectID; join options - keep only matching records. 2016 The joined transect feature class was exported to a shapefile in ArcMap v10.3 by right-clicking the transect layer > data > export data, permanently linking the joined rate fields to the transect attribute table. 2016 The exported transect shapefile was projected in Esri's ArcToolbox (v10.3) > Data Management Tools > Projections and Transformations > Feature > Project. Parameters: input projection - UTM zone XN (NAD83; where X is the corresponding UTM Zone); output projection - geographic coordinates (WGS84); transformation = WGS_1984_(ITRF00)_To_NAD_1983. 2016 Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed. 20201019 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543-1598 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov Vector String 4275 0.0196107641 0.0557517936 Decimal seconds D_WGS_1984 WGS_1984 6378137.0 298.257223563 Attribute Table Table containing attribute information associated with the data set. Producer defined OBJECTID Internal feature number generated for each row of the transect attribute table when stored as a feature class in a geodatabase. This value is the common attribute field when joining to the TransectID value in short-term results output table calculated by DSAS. U.S. Geological Survey 1 4609 BaselineID Unique identification number of the baseline segment. Used by DSAS to determine transect ordering alongshore if multiple baseline segments exist. U.S. Geological Survey 1 84 Group_ Region ID as defined in Gibbs and Richmond (2017). U.S. Geological Survey 2 Hulahula River to the Staines River region Producer defined 3 Staines River to the Sagavanirktok River region Producer defined 4 Sagavanirktok River to the Colville River region Producer defined 33 Tigvariak Island Producer defined TransOrder Assigned by DSAS based on ordering of transects along the baseline. Used to allow user to sort transect data along the baseline from baseline start to baseline end. U.S. Geological Survey 6 4601 ProcTime Date and time (YYYY/MM/DD HH:MM:SS) a transect was processed. This value is automatically assigned by the DSAS extension. U.S. Geological Survey 2012/05/03 15:18:16 2015/11/18 16:13:29 Autogen Assigned by DSAS to indicate whether or not a transect was automatically created by DSAS (1= transect was auto generated by DSAS; 0=transect was not auto-generated). U.S. Geological Survey 0 Transect was not auto-generated by DSAS Producer defined 1 Transect was auto-generated by DSAS Producer defined StartX Unknown Producer defined 379662.94 608714.36 StartY Unknown Producer defined 7763476.37 7825493.63 EndX Unknown Producer defined 379922.09 608982.61 EndY Unknown Producer defined 7763007.24 7825249.41 Azimuth Unknown Producer defined 3.05 359.08 ShoreType User defined shoreline type U.S. Geological Survey Sheltered Island Portions of offshore islands sheltered from direct wave energy. Producer defined Sheltered Mainland A large, continuous extent of land that does not include offshore islands or other detached territories and is sheltered from direct wave energy by offshore islands. Producer defined Shape_Leng Length of the transect created by DSAS Producer defined 96.396000125 638.836882896 TransectId Same value as ObjectID. Used as a permanent and unique identification number for each transect in the output rates table calculated by DSAS. This attribute was used as the common field when joining the rates table (.dbf) to the transect feature class in a geodatabase. U.S. Geological Survey 1 4609 TCD Total cumulative distance in meters from start of baseline to transect location. U.S. Geological Survey 250 444607.64 LRR A linear regression rate-of-change statistic was calculated by fitting a least-squares regression line to all shoreline points for a particular transect. 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. U.S. Geological Survey -10.98 5.8 LR2 The R-squared statistic, or coefficient of determination, is the percentage of variance in the data that is explained by a regression. It is a dimensionless index that ranges from 1.0 to 0.0 and measures how successfully the best-fit line accounts for variation in the data. The smaller the variability of the residual values around the regression line relative to the overall variability, the better the prediction (and closer the R-squared value is to 1.0). U.S. Geological Survey 0 1 LSE The predicted (or estimated) values of y (the distance from baseline in meters) are computed for each shoreline point by using the values of x (the shoreline date) and solving the equation for the best-fit regression line (y=mx+b). The standard error is also called the standard deviation. U.S. Geological Survey 0 55.63 LCI90 The standard error of the slope with confidence interval describes the uncertainty of the reported rate. The LRR rates are determined by a best-fit regression line for the shoreline data at each transect. The slope of this line is the reported rate of change (in meters/year). The confidence interval (LCI) is calculated by multiplying the standard error (also called the standard deviation) of the slope by the two-tailed test statistic at the user-specified 90 percent confidence. This value is often reported in conjunction with the slope to describe the confidence of the reported rate. For example: LRR = 1.2 LCI90 = 0.7 could be reported as a rate of 1.2 (+/-) 0.7 meters/year. U.S. Geological Survey 0 16.424 CalcEra Decade (era) of shorelines used to calculate shoreline change rates. U.S. Geological Survey 1980s, 2000s, 2010s Unknown Producer defined All calculations for length are in meter units and were based on the coincident UTM zone WGS84 Unknown U.S. Geological Survey - Science Base mailing and physical address

CenterDenver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 CA 888-275-8747 sciencebase@usgs.gov CentralBeaufort_sheltered_STlrr_rates.shp 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 on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. Vector Digital Data Set (Polyline) 9.0 Esri polyline shapefile This WinZip file contains the baseline shapefile for use generating transects within the Digital Shoreline Analysis System for the CentralBeaufort Sea coast of Alaska and associated metadata. Use WinZip or pkUnzip 390 https://www.sciencebase.gov/catalog/file/get/5949c4e7e4b062508e359c0a https://doi.org/10.5066/F72Z13N1 Data are downloadable via the World Wide Web (WWW). None This zip file contains data available in Environmental Systems Research Institute (Esri) polyline shapefile format. The user must have ArcGIS or ArcView 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing the data. A free data viewer, ArcExplorer, capable of displaying the data is available from Esri at www.esri.com. 20201019 Ann E. Gibbs U.S. Geological Survey, Pacific Coastal and Marine Science Center Geologist mailing and physical address

2885 Mission Street

Santa Cruz CA 95060-5792 USA 831-460-7540 831-427-4748 agibbs@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 local time