cencal_baseline.shp - Offshore Baseline for Central California Generated to Calculate Cliff Erosion Rates

Frequently-asked questions:


What does this data set describe?

Title:
cencal_baseline.shp - Offshore Baseline for Central California Generated to Calculate Cliff Erosion Rates

Abstract:
Rates of cliff edge erosion were generated in a GIS using the Digital Shoreline Analysis System (DSAS) version 3.2; An ArcGIS extension for calculating shoreline change: U.S. Geological Survey Open-File Report 2005-1304, Thieler, E.R., Himmelstoss, E.A., Zichichi, J.L., and Miller, T.M. The extension is designed to efficiently lead a user through the major steps of shoreline change analysis. This extension to ArcGIS contains three main components that define a baseline, generate orthogonal transects at a user-defined separation along the coast, and calculate rates of change (linear regression, endpoint rate, average of rates, average of endpoints, jackknife).

  1. How should this data set be cited?

    Cheryl Hapke, David Reid, 2007, cencal_baseline.shp - Offshore Baseline for Central California Generated to Calculate Cliff Erosion Rates: Open-File Report 2007-1112, U.S. Geological Survey, Coastal and Marine Geology Program, U.S. Geological Survey, Pacific Science Center, Santa Cruz, California.

    Online links:
    This is part of the following larger work:

    Cheryl Hapke, David Reid, Krystal Green, Mark Borrelli, 2007, National Assessment of Shoreline Change: Part 4: A GIS Compilation of Vector cliff edges and associated change data for the cliffed shorelines of the California Coast: Open-File Report 2007-1112, U.S. Geological Survey, Coastal and Marine Geology Program, U.S. Geological Survey, Pacific Science Center, Santa Cruz.

    Online links:
  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -123.023918
    East: -119.812615
    North: 38.242744
    South: 34.432397

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Calendar date: 2005
    Currentness reference:
    publication date

  5. What is the general form of this data set?

    Geospatial data presentation form: vector digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • String (1)

    2. What coordinate system is used to represent geographic features?

      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees.

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

  7. How does the data set describe geographic features?

    CenCal_Baseline
    Baseline for Central California
    (Source:
    U.S. Geological Survey
    )

    FID
    Internal feature number
    (Source:
    ESRI
    )

    Sequential unique whole numbers that are automatically generated.

    Shape
    Feature geometry.
    (Source:
    ESRI
    )

    Coordinates defining the feature.

    SHAPE_Leng
    RID
    Shape_Le_1
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Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)


  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    Cheryl Hapke
    U.S. Geological Survey
    Geologist
    USGS Patuxent Wildlife Research Center
    University of Rhode Island
    317 Woodward Hall, Dept. of Geosciences
    Kingston, RI 02881
    USA

    401-874-5532 (voice)
    401-874-2190 (FAX)
    chapke@usgs.gov
    Hours of Service: Monday through Friday, 9 a.m. to 5 p.m., Eastern Standard Time
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Why was the data set created?

Historical cliff erosion is considered to be a crucial element in studying the vulnerability of the national coastline.  These data are used in a cliff erosion analysis for the USGS National Assessment Project.

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How was the data set created?

  1. Where did the data come from?

  2. What changes have been made?

    Date: 2006 (change 1 of 2)
    A baseline was manually constructed seaward of, and parallel to, the trend of cliff edges representing two general time periods (1920s-1930s and 1998-2002).  Using DSAS (USGS OFR 2005-1304), transects were generated with a spacing of 20m and transect-cliff edge intersection points were saved to a separate layer.  Transects were manually eliminated to prevent calculation of rates in areas where less than two cliff edges were intersected.
    
    Rates of cliff edge erosion, in units of m/yr, were calculated at each transect using end point rate applied to both cliff edge positions from 1920s-1930s and 1998-2002 (derived from lidar).  End point rate was selected because there were two cliff edges available. Uncertainties are reported in units of m/yr.

    Person responsible for change:
    Cheryl Hapke
    U.S. Geological Survey
    USGS Patuxent Wildlife Research Center
    University of Rhode Island
    Coastal Field Station
    317 Woodward Hall, Dept. of Geosciences
    Kingston, RI 02881
    USA

    401-874-5532 (voice)
    401-874-2190 (FAX)
    chapke@usgs.gov
    Hours of Service: Monday through Friday, 8 a.m. to 5 p.m., Eastern Standard Time

    Date: 20070605 (change 2 of 2)
    Data were projected from UTM zone 10 to geographic
    
    Tool: ArcGIS > ArcToolbox > Toolboxes > Data Management Tools > Project
    
    Command issued:
    ['GCS_North_American_1983',DATUM['D_North_American_1983',SHPERIOD['GRS_1980',6378137.0,298.25722101]],PRIMEM['Greenwich',0.0],UNIT['Degree',0.0174532925199433]]

    Person responsible for change:
    Emily Himmelstoss
    U.S. Geological Survey
    Geologist
    384 Woods Hole Road
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2262 (voice)
    508-457-2310 (FAX)
    ehimmelstoss@usgs.gov

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How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

    The attributes in this dataset are based on the Digital Shoreline Analysis System (DSAS) version 3.2; An ArcGIS extension for calculating shoreline change (Thieler, E.R., Himmelstoss, E.A., Zichichi, J.L., and Miller, T.M. 2005. U.S. Geological Survey Open-File Report 2005-1304).  The data has gone through a series of QA/QC procedures, and is therefore believed to accurately reflect the data gathered as part of the National Assessment of Shoreline Change Study.

  2. How accurate are the geographic locations?

    A Baseline was generated within ArcGIS to be used by the Digital Shoreline Anaylsis System (http://pubs.usgs.gov/of/2005/1304/) in the calculation of cliff erosion rates. Please visit our full report on cliff erosion along the Coastline of California (http://pubs.usgs.gov/of/2007/1133/) for more information about this analysis.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    This baseine data represents a generalization of the coastline of California used by DSAS.  Remaining gaps in this data, if applicable, are a consequence of non-existing cliff edges data.

  5. How consistent are the relationships among the observations, including topology?

    Baseline generation was made as part of the calculation process for the Digital Shoreline Analysis System an Extension for ArcGIS (http://pubs.usgs.gov/of/2005/1304/).  No additional checks for topological consistency were performed on the data.

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How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access constraints: None
Use constraints:
Public domain data are freely redistributable with proper metadata and source attribution.  The U.S. Geological Survey (USGS) must be referenced as the originator of the dataset in any future products or research derived from these data.

Distributor 1 of 1

  1. Who distributes the data set?

    U.S. Geological Survey
    Pacific Science Center
    400 Natural Bridges Drive
    Santa Cruz, CA 95060
    USA

    831-427-4450 (voice)
    831-427-4748 (FAX)

  2. What's the catalog number I need to order this data set?

    downloadable data

  3. What legal disclaimers am I supposed to read?

    Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, these data and information are provided with the understanding that they are not guaranteed to be usable, timely, accurate, or complete. Users are cautioned to consider carefully the provisional nature of these data and information before using them for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences. Conclusions drawn from, or actions undertaken on the basis of, such data and information are the sole responsibility of the user.
    
    Neither the U.S. Government nor any agency thereof, 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 data, software, information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights.
    
    Trade, firm, or product names and other references to non-USGS products and services are provided for information only and do not constitute endorsement or warranty, express or implied, by the USGS, USDOI, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.

  4. How can I download or order the data?

    • Availability in digital form:


    • Data format:
      in format SHP (version Unspecified)
      ESRI Polyline Shapefile. The DBF file contains the attribute data in dBASE format. The PRJ file contains the coordinate system information. The SBN and SBX files contain the spatial index of the geospatial data. The SHP file contains the geospatial data. The SHX file contains the index of the geospatial data. The XML file contains the metadata describing the data set.
      Size: 0.348
      Network links:
      http://pubs.usgs.gov/of/2007/1112/CCal.zip
      http://pubs.usgs.gov/of/2007/1112/

    • Cost to order the data: None


  5. Is there some other way to get the data?

  6. What hardware or software do I need in order to use the data set?

    These data are available in Environmental Systems Research Institute (ESRI) 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.

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Who wrote the metadata?

Dates:
Last modified: 20070319

Metadata author:
Cheryl Hapke
U.S. Geological Survey
USGS Patuxent Wildlife Research Center
University of Rhode Island
Coastal Field Station
317 Woodward Hall, Dept. of Geosciences
Kingston, RI 02881
USA

401-874-5532 (voice)
401-874-2190 (FAX)
chapke@usgs.gov

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)

Metadata extensions used:
  • http://www.esri.com/metadata/esriprof80.html

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