APPENDICES

APPENDIX A: THE DATA GROUPS, A QUICK REFERENCE

THE DATA GROUPS: A QUICK REFERENCE

The following provides a listing and description of the data variables and other pertinent information for each of the five data groups. The ARC/INFO version of these files, contain several additional variables. These additional variables are system variables. For data groups WCGRID and WCRISK, the system variables AREA, PERIMETER, COVERNAME# [i.e., cover name pound sign, an internal polygon, point, or line identification number (e.g., WCGRID#, WCPOINT#, and WCLINE# respectively)], and COVERNAME-ID [i.e., cover name dash identification number, an external polygon, point, or line identification number (e.g. WCGRID-ID, WCPOINT-ID, and WCLINE-id respectively)]. The external identification number is present in both the export (.E00) and ASCII (.ASC) files and is used to identify the 0.25° by 0.25° grid cell, point, or 1:2,000,000 digitized line segment to which the data record belongs.

  1. Data Group WCGRID: Gridded polygon data for 22 data variables from the following data sets: elevation, geology, geomorphology, sea-level trend, shoreline displacement(erosion/accretion), tidal range, and wave heights. (A value of -9999.99 or 9999 indicates no data are available for the given data cell for a given data variable.)

    Data Format - ARC/INFO coverage and flat ASCII file with data values for each 0.25° latitude by 0.25° longitude grid cell on the U.S. West Coast.

    File Storage - ARC/INFO coverage name is WCGRID.E00 (File 4) ASCII file name is WCGRID.ASC (File 5).

    Data Variables

    ELAVG - Average elevation calculated from all positive 5´ by 5´ grid cells within a given 0.25° grid cell; values expressed in meters.

    ELMAX - Maximum elevation of all the positive 5´ by 5´ grid cells for a given 0.25° grid cell; values expressed in meters.

    ELMIN - Minimum elevation of all the positive 5´ by 5´ grid cells for a given 0.25° grid cell; values expressed in meters.

    ELNUM - Number of 5´ by 5´ grid cells used in calculating ELAVG, ELMIN, and ELMAX for a given 0.25° grid cell.

    GL - Ordinal value indicating the type and resistance of the rocks within a given 0.25° grid cell to erosion through physical and chemical weathering.

    GM - Ordinal value indicating the type and susceptibility of the landforms within a given 0.25° grid cell to inundation and erosion.

    SLR - Relative sea-level trend within a given 0.25° grid cell; values are expressed in mm/year. Data values are based on the point data in data group WCPOINT.

    SLG - Geologic trend variable. In this data base this variable is 0.0 for all 0.25 grid cells with a relative sea-level trend value, and 9999.99 for all grid cells without a relative sea-level trend value. This data variable has been included to ensure compatibility between the data bases in this series of NDPs (i.e., NDP-043A, NDP-043B, and NDP-043C). See Appendix D for additional geologic trends based on long-term geologic data from raised marine terraces and 14C data.

    SLC - Corrected sea-level trend. Since the geologic trend variable contains values of 0.0, this variable appears identical to the relative sea-level trend variable; and is included for compatibility within this series of NDPs. Some long-term geologic trends are listed in Appendix D.

    SLS - Local subsidence trend derived from tide-gauge data and corrected for the global eustatic sea-level trend (i.e., 1.50); values are expressed in mm/year. Data values are based on the point data in data group WCPOINT.

    SLYR - Number of years of record used in estimating the sea-level trend for each 0.25° grid cell (grid cells in which tide-gauge stations do not occur have been assigned a zero value.) Data values are based on the point data in data group WCPOINT.

    ERAVG - Average of the mean long-term erosion trend values for a given 0.25° grid cell; values expressed in meters.

    ERMAX - Maximum of the mean long-term erosion trends for a given 0.25° grid cell; values expressed in meters.

    ERMIN - Minimum of the mean long-term erosion trends for a given 0.25° grid cell; values expressed in meters.

    ERNUM - Number of 3´, 7.5´, or 15´ grid cells (i.e., format of original data source) used in calculating ERAVG, ERMIN, or ERMAX for a given 0.25° grid cell.

    TRAVG - Average of the mean-tide-range values for all tide stations occurring within a given 0.25° grid cell in 1992 (the mean tide range is the difference in height between mean high water and mean low water for 1992). Data values are expressed in meters and are based on the point data in data group WCPOINT.

    TRMAX - Maximum tide range measured for all gauge stations that occurred within a given 0.25° grid cell in 1992 (this value may be the "spring" or "diurnal" tide range, depending on geographic location). Data values are expressed in meters and are based on the point data in data group WCPOINT.

    TRLVL - Average of the mean-tide-level values for all tide stations occurring within a given 0.25° grid cell in 1992 (the mean tide level is a plane midway between mean low water and mean high water in 1992). Values are reckoned from chart datum, are expressed in meters, and are based on the point data in data group WCPOINT.

    TRNUM - Number of tide-gauge stations used in calculating TRAVG, TRMAX, and TRLVL for a given 0.25° grid cell. Data values are based on the point data in data group WCPOINT.

    WHAVG - 20-year mean wave height calculated for each 0.25° grid cell: values expressed in meters.

    WHMAX - Maximum significant wave height for each 0.25° grid cell; values expressed in meters.

    WHSD - Standard deviation of the mean wave heights experienced within each 0.25° grid cell; values expressed in meters.

  2. Data Group WCRISK: Gridded polygon data for the seven classified risk variables. The risk variables contain values ranging from 0 to 5. A value of zero indicates no data are available for a given data variable, for a given grid cell. When the value for a given variable is greater than zero, the value indicates the relative risk of each 0.25° grid cell to inundation or erosion, with 5 indicating the greatest risk.

    Data Format - ARC/INFO coverage and flat ASCII file with data values for each 0.25° latitude by 0.25° longitude grid cell on the U.S. West Coast.

    File Storage - ARC/INFO coverage name is WCRISK.E00 (File 12) ASCII file name is WCRISK.ASC (File 13).

    Data Variables

    ELR - Classified version of the mean elevation data variable (i.e., ELAVG).

    GLR - Classified version of the geology data variable (i.e., GL).

    GMR - Classified version of the geomorphology data variable (i.e., GM).

    LSR - Classified version of the local subsidence trend data variable (i.e., SLS).

    ERR - Classified version of the mean erosion/accretion data variable (i.e., ERAVG).

    TRR - Classified version of the mean-tide-range data variable (i.e., TRAVG).

    WHR - Classified version of the maximum significant wave-height variable (i.e., WHMAX).

  3. Data Group WCLINE: 1: 2,000,000 digitized line segment data for the 22 original and 7 relative risk data variables from each of the seven data sets (i.e., elevation, geology, geomorphology, sea-level trend, shoreline displacement, tidal range, and wave heights). A value of -9999.99 or 9999 indicates no data are available for the given data cell for a given data variable.)

    Data Format - ARC/INFO coverage and flat ASCII file with data values for each line segment that describes the U.S. West Coast.

    File Storage - ARC/INFO coverage name is WCLINE.E00 (File 12) ASCII file name is WCLINE.ASC (File 13).

    Data Variables

    ELAVG - Average elevation calculated from all positive 5´ by 5´ grid cells within a given 0.25° grid cell; values expressed in meters.

    ELMAX - Maximum elevation of all the positive 5´ by 5´ grid cells for a given 0.25°grid cell; values expressed in meters.

    ELMIN - Minimum elevation of all the positive 5´ by 5´ grid cells for a given 0.25° grid cell; values expressed in meters.

    ELNUM - Number of 5´ by 5´ grid cells used in calculating ELAVG, ELMIN, and ELMAX for a given 0.25° grid cell.

    ELR - Classified version of the mean elevation data variable (i.e., ELAVG).

    GL - Ordinal value indicating the type and resistance of the rocks within a given region to erosion through physical and chemical weathering.

    GLR - Classified version of the geology data variable (i.e., GL).

    GM - Ordinal value indicating the type and susceptibility of the landforms within a given region to inundation and erosion.

    GMR - Classified version of the geomorphology data variable (i.e., GM).

    SLR - Relative sea-level trend within a given 0.25° grid cell; values are expressed in mm/year. Data values are based on the point data in data group WCPOINT.

    SLG - Geologic trend variable. In this data base this variable is 0.0 for all 0.25 grid cells with a relative sea-level trend value, and 9999.99 for all grid cells without a relative sea-level trend value. This data variable has been included to ensure compatibility among the NDPs in this series (i.e., NDP-043A, NDP-043B, and NDP-043C). See Appendix D for additional geologic trends based on long-term geologic data from raised marine terraces and 14C data.

    SLC - Corrected sea-level trend. Since the geologic trend variable contains values of 0.0, this variable appears identical to the relative sea-level trend variable; and is included only for compatibility within this series of NDPs. Some long-term geologic trends are listed in Appendix D.

    SLS - Local subsidence trend derived from tide-gauge data and corrected for the global eustatic sea-level trend (i.e., 1.50); values are expressed in mm/year. Data values are based on the point data in data group WCPOINT.

    SLYR - Number of years of record used in estimating the sea-level trend for each 0.25° grid cell (grid cells in which tide-gauge stations do not occur have been assigned a zero value.) Data values are based on the point data in data group WCPOINT.

    LSR - Classified version of the local subsidence trend data variable (i.e., SLS).

    ERAVG - Average of the mean long-term erosion trend values for a given 0.25° grid cell; values expressed in meters.

    ERMAX - Maximum of the mean long-term erosion trends for a given 0.25° grid cell; values expressed in meters.

    ERMIN - Minimum of the mean long-term erosion trends for a given 0.25° grid cell; values expressed in meters.

    ERNUM - Number of 3´, 7.5´, or 15´ grid cells (i.e., format of original data source) used in calculating ERAVG, ERMIN, or ERMAX for a given 0.25° grid cell.

    ERR - Classified version of the mean erosion/accretion data variable (i.e., ERAVG).

    TRAVG - Average of the mean-tide-range values for all tide stations occurring within a given 0.25° grid cell in 1992 (the mean tide range is the difference in height between mean high water and mean low water for 1992). Data values are expressed in meters and are based on the point data in data group WCPOINT.

    TRMAX - Maximum tide range measured for all gauge stations that occurred within a given 0.25° grid cell in 1992 (this value may be the "spring" or "diurnal" tide range, depending on geographic location). Data values are expressed in meters and are based on the point data in data group WCPOINT.

    TRLVL - Average of the mean-tide-level values for all tide stations occurring within a given 0.25° grid cell in 1992 (the mean tide level is a plane midway between mean low water and mean high water in 1992). Values are reckoned from chart datum, are expressed in meters, and are based on the point data in data group WCPOINT.

    TRNUM - Number of tide-gauge stations used in calculating TRAVG, TRMAX, and TRLVL for a given 0.25° grid cell. Data values are based on the point data in data group WCPOINT.

    TRR - Classified version of the mean-tide-range data variable (i.e., TRAVG).

    WHAVG - 20-year mean wave height calculated for each 0.25° grid cell: values expressed in meters.

    WHMAX - Maximum significant wave height for each 0.25° grid cell; values expressed in meters.

    WHSD - Standard deviation of the mean wave heights experienced within each 0.25° grid cell; values expressed in meters.

    WHR - Classified version of the maximum significant wave-height variable (i.e.,WHMAX).

  4. Data Group WCPOINT: Point data for the stations used in constructing the sea-level trend and tidal-range data sets. (Missing data values are indicated by the value 0.0 for real numbers, 0 for integers, and blank spaces [i.e., ' '] for station names.)

    Data Format - ARC/INFO coverage and flat ASCII file with data values for each point (i.e., station) on the U.S. West Coast.

    File Storage - ARC/INFO coverage name is WCPOINT.E00 (File 16) ASCII file name is WCPOINT.ASC (File 17).

    Data Variables

    SLLONG - Longitude of the tide-gauge station used for determining the sea-level trend variables.

    SLLAT - Latitude of the given tide-gauge station used for determining the sea-level trend variables.

    SLR - Relative sea-level trend for the tide-gauge station; values expressed in mm/year.

    SLG - Geologic trend variable. In this data base this variable is 0.0 for all 0.25 grid cells with a relative sea-level trend value, and 9999.99 for all grid cells without a relative sea-level trend value. This data variable has been included to ensure compatibility among the NDPs in this series (i.e., NDP-043A, NDP-043B, and NDP-043C). See Appendix D for additional geologic trends based on long-term geologic data from raised marine terraces and 14C data.

    SLC - Corrected sea-level trend. Since the geologic trend variable contains values of 0.0, this variable appears identical to the relative sea-level trend variable; and is included only for compatibility within this series of NDPs. Some long-term geologic trends are listed in Appendix D.

    SLS - Local subsidence trend derived from tide-gauge data and corrected for the global eustatic sea-level trend (i.e., 1.50); values are expressed in mm/year.

    SLYR - Period of record in years of the tide-gauge station used for determining the sea-level trend variables.

    SLNAME - Station name of the tide-gauge station used for determining the sea-level trend variables.

    TRLONG - Longitude of the tide-gauge station used for determining the tide-range variables.

    TRLAT - Latitude of the given tide-gauge station used for determining the tide-range variables.

    TRAVG - Difference (i.e., range) in height between mean high water and mean low water in 1992; values expressed in meters.

    TRMAX - Difference (i.e., range) in height between the highest high tide and the lowest low tide in 1992 (this value may be the "spring" or "diurnal" tide range, depending on geographic location); values expressed in meters.

    TRLVL - Mean tide level is a plane midway between mean low water and mean high water in 1992; values expressed in meters. Values are reckoned from chart datums (i.e., the West Coast Mean Low Water Datum).

    TRID - Station number (as given in the 1992 Tide Tables) of the given tide gauge station used in determining the tide-range variables.

    TRNAME - Station name (as given in the 1992 Tide Tables) of the given tide gauge station used in determining the tide-range variables.

  5. Data Group WCOAST: 1:2,000,000 digitized coastline of the U.S. West Coast.

    Data Format - ARC/INFO coverage and flat ASCII file containing the latitude-longitude coordinates of line segments that describe the U.S. West Coast.

    File Storage - ARC/INFO coverage name is WCOAST.E00 (File 20) ASCII file name is WCOAST.ASC (File 21).

Data Variables

Unlike the other data groups within this data base, this coverage contains line segments (or arcs) that are used to describe the West Coast. The coastline provided has no data variables associated with the line segments. However, simple overlay commands (such as INTERSECT or IDENTITY) in ARC/INFO may be used to transfer the gridded data values to the coastal segments, thus simplifying the interpretation of any derived indices. The segment identification numbers match those used in the flat ASCII file WCLINE.ASC.