Glenn, R. J.
Overbeck, J.R.
2018
Alaska coastal shorelines and shoreline change statistics for the community of Kwigillingok
digital data
Anchorage, Alaska, United States
Alaska Division of Geological & Geophysical Surveys
The Division of Geological & Geophysical Surveys has (1) delineated past shoreline positions fronting Alaska communities using orthorectified historically and recently collected aerial imagery, (2) computed rates of shoreline change along cross shore transects cast approximately every 50 meters along the delineated shorelines using the Digital Shoreline Analysis System (DSAS; Thieler and others, 2009), and (3) summarized the results for each community in the region. This geodatabase for the community of Kwigillingok includes shoreline positions, shoreline envelopes, and community location identifiers, as well as geodatabase tables of shoreline change statistics, shoreline change analysis transect information, and summary shoreline change statistics.
Coastlines are dynamic features that change shape and position on a range of timescales. These changes can result in erosion or aggradation of the coastline fronting valued systems (e.g. community infrastructure). This geodatabase for the community of Kwigillingok includes shoreline positions, shoreline envelopes, and community location identifiers, as well as geodatabase tables of shoreline change statistics, shoreline change analysis transect information, and summary shoreline change statistics.
1953
2015
publication date
As needed
-163.167027
-163.0899
59.887018
59.847345
ISO 19115 Topic Category
geoscientificInformation
Alaska Division of Geological & Geophysical Surveys
Coastal
Coastal and River
Coastal Erosion
Engineering
Engineering Geology
Environmental
Geologic
Geological Process
Geologic Hazards
Geology
Geomorphology
Hazards
Surface
Surficial
Surficial Geology
Alaska Division of Geological & Geophysical Surveys
Kwigillingok
This report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below).
Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product.
State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys Coastal Hazards Program
mailing and physical
3651 Penland Pkwy
Anchorage
AK
99508
USA
907-451-5026
dggspubs@alaska.gov
8 am to 4:30 pm, Monday through Friday, except State holidays
These materials were prepared in partnership with the Federal Emergency Management Agency through a Cooperative Technical Partner grant. Data were produced by the Alaska Division of Geological & Geophysical Surveys, the U.S. Geological Survey, and the National Park Service.
DGGS staff have performed visual qualitative assessment of each shoreline file to ensure consistency between the digitized lines and originating images. Several factors have potential to introduce uncertainty in the measured or interpreted results. The factors include: positional uncertainty associated with ground control points, horizontal uncertainty associated with orthorectification of the aerial imagery, spatial uncertainty associated with the spatial resolution of the imagery, and uncertainty due to shoreline indicator interpretation during the digitization process. The accompanying delivery report provides additional information about the procedures used to determine values for shoreline positions, shoreline envelopes, and community location identifiers, shoreline change statistics, shoreline change analysis transect information, and summary shoreline change statistics.
not applicable
Gaps in shoreline data may occur where a shoreline indicator is not identifiable (example: poorly defined shoreline indicator, cloud cover in imagery, etc.) or does not exist (example: tidal inlet, revetment or other coastal structure).
Shoreline positions are a representation of a linear shoreline feature at a given point in time. These data were visually interpreted from historical and current orthorectified aerial photographs and delineated in ArcGIS. These accuracies are dependent on a number of variables. The details of their calculation are explained in the associated publications: Gould, A.I., Kinsman, N.E.M., and Hendricks, M.D., 2015, Guide to projected shoreline positions in the Alaska shoreline change tool: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 158, 11 p. doi:10.14509/29503
Gould, A.I.
Kinsman, N.E.M.
Hendricks, M.D.
2015
Guide to projected shoreline positions in the Alaska shoreline change tool
Miscellaneous Publication
MP 158
Fairbanks, Alaska, United States
Alaska Division of Geological & Geophysical Surveys
11 p
http://doi.org/10.14509/29503
paper
2015
publication date
Gould and others, 2015
Projected shoreline positions
Himmelstoss, E.A.
2009
DSAS 4.0 Installation Instructions and User Guide in: Thieler, E.R., Himmelstoss, E.A., Zichichi, J.L., and Ergul, Ayhan. 2009 Digital Shoreline Analysis System (DSAS) version 4.0 - An ArcGIS extension for calculating shoreline change
U.S. Geological Survey Open-File Report
OFR 2008-1278
United States
U.S. Geological Survey
paper
2009
publication date
Himmelstoss, 2009
Projected shoreline positions
Thieler, E.E.
Himmelstoss, E.A.
Zichichi, J.L.
Ergul, Ayhan
2008
The digital shoreline analysis system (DSAS) version 4.0 - An ArcGIS extension for calculating shoreline change
Open-File Report
OF 2008-1278
United States
U.S. Geological Survey
http://dggs.alaska.gov/pubs/id/29507
ArcGIS extension
2008
publication date
Thieler, E.E. and others, 2008
Projected shoreline positions
Historical shoreline compilation - Using orthorectified historically and recently collected aerial imagery, we delineated past shoreline positions fronting Alaska communities. The agency or organization that produced the imagery used to delineate shoreline position is noted in the Shoreline Positions data table.
2017
Rates of shoreline change - We computed rates of shoreline change along cross shore transects cast approximately every 50 meters along the delineated shorelines using the Digital Shoreline Analysis System
2017
Summary results - We summarized the results for each community by computing summary statistics of the resulting shoreline change statistics at community-located profiles.
2017
vector
Universal Transverse Mercator
3
0.999600
-165
0
500000.000000
0
coordinate pair
0.0001
0.0001
Meters
World Geodetic System of 1984
WGS 84
6378137
298.257223563000025
KWIGILLINGOK
point file with community name, location, profile location, compiler, and date range of shoreline imagery.
Alaska Division of Geological & Geophysical Surveys (DGGS)
KWIGILLINGOK_DSAS_Intersect_Table
The DSAS Transect Intersect table gives the X and Y coordinates of each intersection between the shorelines and transects.
Alaska Division of Geological & Geophysical Surveys (DGGS)
TransectID
Unique identifier for transect intersecting with the shorelines.
this study
Integer
BaselineID
Unique identifier for which baseline segment the transect was cast from.
this study
Integer
ShorelineID
Date of the shoreline the transect is intersecting.
this study
String
Distance
Distance from the baseline to the intersection for the shoreline from a single date.
this study
Double
IntersectX
X coordinate of intersection.
this study
Double
IntersectY
Y coordinate of intersection.
this study
Double
KWIGILLINGOK_DSAS_Rates_Table
Each method used to calculate shoreline rates of change is based on measured differences between shoreline positions through time. The reported rates are expressed as meters of change along transects per year. When the user-selected rate-change calculations are processed, DSAS merges the individual module calculations, and the output is made available as a table in ArcMap. The rate-change statistics provided with DSAS have the standardized field headings, listed below (Himmelstoss, 2009). Some of the shoreline statistic values listed below require greater than 3 shoreline positions to calculate the statistic. If the shoreline statistic is a null value, there were not enough shorelines analyzed to compute that statistic.
Alaska Division of Geological & Geophysical Surveys (DGGS)
TransectId
Unique identifier for transect intersecting with the shorelines.
this study
Integer
TCD
Total cumulative distance of shoreline alongshore in meters.
this study
Double
EPR
The end point rate is calculated by dividing the distance of shoreline movement by the time elapsed between the oldest and the most recent shoreline (Himmelstoss, 2009).
this study
Double
ECI
Confidence Interval of Endpoint Rate
this study
Double
SCE
The shoreline change envelope reports a distance, not a rate. The SCE is the distance between the shoreline farthest from and closest to the baseline at each transect in meters. This represents the total change in shoreline movement for all available shoreline positions and is not related to their dates (Himmelstoss, 2009).
this study
Double
NSM
The net shoreline movement reports a distance, not a rate. The NSM is associated with the dates of only two shorelines. It reports the distance between the oldest and youngest shorelines for each transect in meters (Himmelstoss, 2009).
this study
Double
LMS
In ordinary and weighted least-squares regression, the best-fit line is placed through the points in such a way as to minimize the sum of the squared residuals. In the linear regression method, the sample data are used to calculate a mean offset, and the equation for the line is determined by minimizing this value so that the input points are positioned as close to the regression line as possible. In the least median of squares method the median value of the squared residuals is used instead of the mean to determine the best-fit equation for the line. This method is a more robust regression estimator that minimizes the influence of an anomalous outlier on the overall regression equation. The Least Median of Squares rate is the slope of this best-fit line (Himmelstoss, 2009).
this study
Double
WLR
In a weighted linear regression, more reliable data are given greater emphasis or weight towards determining a best-fit line. In the computation of rate-of-change statistics for shorelines, greater emphasis is placed on data points for which the position uncertainty is smaller. The Weighted Linear Regression Rate is the slope of that best-fit line (Himmelstoss, 2009).
this study
Double
WR2
R-squared of Weighted Linear Regression
this study
Double
WSE
Standard Error of Linear Regression
this study
Double
WCI90
Confidence Interval of Weighted Linear Regression
this study
Double
LRR
A linear regression rate-of-change statistic can be determined by fitting a least-squares regression line to all shoreline points for a particular transect. The 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 that line (Himmelstoss, 2009).
this study
Double
LR2
R-squared of Linear Regression
this study
Double
LSE
Standard Error of Linear Regression
this study
Double
LCI90
Confidence Interval of Linear Regression
this study
Double
KWIGILLINGOK_Relationship_Class
Relates values in the community table to the Statistics_Table using Location_ID
Alaska Division of Geological & Geophysical Surveys (DGGS)
KWIGILLINGOK_Shoreline_Envelope
The shoreline envelope feature class was created using the positional outputs of the DSAS analysis. The shoreline envelope is a line between the shoreline position furthest from land and most landward, which shows the range of shoreline position locations at one transect. Shoreline envelopes show how much change has occurred at each transect between the time periods analyzed.
Alaska Division of Geological & Geophysical Surveys (DGGS)
Azimuth
Used to record the azimuth of the transect measured in degrees clockwise from north.
this study
Double
Group_
Identifier for which group the transect is in based on Baseline ID. Values in this field assigned by DSAS are based on input by user for grouping transects.
this study
Integer
BaselineID
Identifier for which baseline segment the transect was cast from.
this study
Integer
TransOrder
Transect order, from 1 to x number of transects. Assigned by DSAS on the basis of transect order along the baseline or baselines. This field provides the user with a method to sort transect data from the start of the baseline segment with an ID=1 and increment sequentially to the end of the final baseline segment (Himmelstoss, 2009).
this study
Integer
Proctime
Time and date of when each transect was cast.
this study
String
StartX
Assigned by DSAS automatically to record the X coordinate of the beginning of the transect.
this study
Double
StartY
Assigned by DSAS automatically to record the Y coordinate of the beginning of the transect.
this study
Double
EndX
Assigned by DSAS automatically to record the X coordinate of the end of the transect.
this study
Double
EndY
Assigned by DSAS automatically to record the Y coordinate of the end of the transect.
this study
Double
KWIGILLINGOK_Shorelines
Shoreline positions are a representation of a linear shoreline feature at a given point in time. These data were visually interpreted from historical and current orthorectified aerial photographs and delineated in ArcGIS.
Alaska Division of Geological & Geophysical Surveys (DGGS)
Date_
Acquisition date of the imagery used to delineate shoreline position.
this study
String
Uncertainty
Sum of squares of four uncertainty values associated with a shoreline position, including positional uncertainty associated with ground control points, horizontal uncertainty associated with orthorectification of the aerial imagery, spatial uncertainty associated with the spatial resolution of the imagery, and uncertainty due to shoreline indicator interpretation during the digitization process (Gould and others, 2015).
this study
Double
Digitizer
Name of the digitizer who delineated the shoreline.
this study
SString
Agency
Name of the agency that delineated the shoreline.
this study
String
SIndicator
Shoreline indicator used to delineate shoreline position (e.g. visible wet/dry line or vegetation line; Gould and others, 2015).
this study
String
Release_Date
Date the shoreline was released/published by the originating agency
this study
Double
Source
Source agency or organization of the imagery used to delineate shoreline position.
this study
String
KWIGILLINGOK_Statistics_Table
Shoreline statistics at the transects are variable along the coast. In order to evaluate shoreline change for alongshore segments surrounding community locations, these alongshore shoreline statistics have been quantified using further statistics. The community statistics table shows the mean, standard deviation, etc. of a group of transects for particular alongshore location (as defined by the community feature class).
Alaska Division of Geological & Geophysical Surveys (DGGS)
Community_Name
Name of community.
this study
Double
Profile_Location
Specific name of the community site location (if more than one site per community).
this study
Double
Statistics_Description
Type of statistic (mean, standard deviation, etc.) for each of the shoreline change statistics (End Point Rate, Net Shoreline Movement, etc.)
this study
Double
EPR
The end point rate is calculated by dividing the distance of shoreline movement by the time elapsed between the oldest and the most recent shoreline (Himmelstoss, 2009).
this study
Double
ECI
Confidence Interval of Endpoint Rate
this study
Double
SCE
The shoreline change envelope reports a distance, not a rate. The SCE is the distance between the shoreline farthest from and closest to the baseline at each transect in meters. This represents the total change in shoreline movement for all available shoreline positions and is not related to their dates (Himmelstoss, 2009).
this study
Double
NSM
The net shoreline movement reports a distance, not a rate. The NSM is associated with the dates of only two shorelines. It reports the distance between the oldest and youngest shorelines for each transect in meters (Himmelstoss, 2009).
this study
Double
LMS
In ordinary and weighted least-squares regression, the best-fit line is placed through the points in such a way as to minimize the sum of the squared residuals. In the linear regression method, the sample data are used to calculate a mean offset, and the equation for the line is determined by minimizing this value so that the input points are positioned as close to the regression line as possible. In the least median of squares method the median value of the squared residuals is used instead of the mean to determine the best-fit equation for the line. This method is a more robust regression estimator that minimizes the influence of an anomalous outlier on the overall regression equation. The Least Median of Squares rate is the slope of this best-fit line (Himmelstoss, 2009).
this study
Double
WLR
In a weighted linear regression, more reliable data are given greater emphasis or weight towards determining a best-fit line. In the computation of rate-of-change statistics for shorelines, greater emphasis is placed on data points for which the position uncertainty is smaller. The Weighted Linear Regression Rate is the slope of that best-fit line (Himmelstoss, 2009).
this study
Double
WR2
R-squared of Weighted Linear Regression
this study
Double
WSE
Standard Error of Linear Regression
this study
Double
WCI90
Confidence Interval of Weighted Linear Regression
this study
Double
LRR
A linear regression rate-of-change statistic can be determined by fitting a least-squares regression line to all shoreline points for a particular transect. The 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 that line (Himmelstoss, 2009).
this study
Double
LR2
R-squared of Linear Regression
this study
Double
LSE
Standard Error of Linear Regression
this study
Double
LCI90
Confidence Interval of Linear Regression
this study
Double
Location_ID
Unique numbered identifier for each community site.
this study
Double
KWIGILLINGOK_Transects
Transects that are automatically generated by DSAS at a 90 degree angle to the user-specified baseline.
Alaska Division of Geological & Geophysical Surveys (DGGS)
Azimuth
Used to record the azimuth of the transect measured in degrees clockwise from north.
this study
Double
Group_
Identifier for which group the transect is in based on Baseline ID. Values in this field assigned by DSAS are based on input by user for grouping transects.
this study
Integer
TransectId
Unique identifier for transect intersecting with the shorelines.
this study
Integer
BaselineID
Identifier for which baseline segment the transect was cast from.
this study
Integer
TransOrder
Transect order, from 1 to x number of transects. Assigned by DSAS on the basis of transect order along the baseline or baselines. This field provides the user with a method to sort transect data from the start of the baseline segment with an ID=1 and increment sequentially to the end of the final baseline segment (Himmelstoss, 2009).
this study
Integer
Proctime
Time and date of when each transect was cast.
this study
String
StartX
Assigned by DSAS automatically to record the X coordinate of the beginning of the transect.
this study
Double
StartY
Assigned by DSAS automatically to record the Y coordinate of the beginning of the transect.
this study
Double
EndX
Assigned by DSAS automatically to record the X coordinate of the end of the transect.
this study
Double
EndY
Assigned by DSAS automatically to record the Y coordinate of the end of the transect.
this study
Double
TCD
Total cumulative distance of shoreline alongshore in meters.
this study
Double
EPR
The end point rate is calculated by dividing the distance of shoreline movement by the time elapsed between the oldest and the most recent shoreline (Himmelstoss, 2009).
this study
Double
ECI
Confidence Interval of Endpoint Rate
this study
Double
SCE
The shoreline change envelope reports a distance, not a rate. The SCE is the distance between the shoreline farthest from and closest to the baseline at each transect in meters. This represents the total change in shoreline movement for all available shoreline positions and is not related to their dates (Himmelstoss, 2009).
this study
Double
NSM
The net shoreline movement reports a distance, not a rate. The NSM is associated with the dates of only two shorelines. It reports the distance between the oldest and youngest shorelines for each transect in meters (Himmelstoss, 2009).
this study
Double
LMS
In ordinary and weighted least-squares regression, the best-fit line is placed through the points in such a way as to minimize the sum of the squared residuals. In the linear regression method, the sample data are used to calculate a mean offset, and the equation for the line is determined by minimizing this value so that the input points are positioned as close to the regression line as possible. In the least median of squares method the median value of the squared residuals is used instead of the mean to determine the best-fit equation for the line. This method is a more robust regression estimator that minimizes the influence of an anomalous outlier on the overall regression equation. The Least Median of Squares rate is the slope of this best-fit line (Himmelstoss, 2009).
this study
Double
WLR
In a weighted linear regression, more reliable data are given greater emphasis or weight towards determining a best-fit line. In the computation of rate-of-change statistics for shorelines, greater emphasis is placed on data points for which the position uncertainty is smaller. The Weighted Linear Regression Rate is the slope of that best-fit line (Himmelstoss, 2009).
this study
Double
WR2
R-squared of Weighted Linear Regression
this study
Double
WSE
Standard Error of Linear Regression
this study
Double
WCI90
Confidence Interval of Weighted Linear Regression
this study
Double
LRR
A linear regression rate-of-change statistic can be determined by fitting a least-squares regression line to all shoreline points for a particular transect. The 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 that line (Himmelstoss, 2009).
this study
Double
LR2
R-squared of Linear Regression
this study
Double
LSE
Standard Error of Linear Regression
this study
Double
LCI90
Confidence Interval of Linear Regression
this study
Double
State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys Coastal Hazards Program
mailing and physical
3651 Penland Pkwy
Anchorage
AK
99508
USA
907-451-5026
dggspubs@alaska.gov
8 am to 4:30 pm, Monday through Friday, except State holidays
The State of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity, whether from the use of the electronic services or products, any failure thereof, or otherwise, and in no event will the State of Alaska's liability to the requestor or anyone else exceed the fee paid for the electronic service or product.
geodatabase
http://dggs.alaska.gov/
Free download
20180504
Simone Montayne
mailing and physical
3354 College Road
Fairbanks
AK
99709-3707
USA
907-451-5020
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
If the user has modified this metadata file in any way, the user is obligated to describe the types of modifications the user has made. User specifically agrees not to misrepresent this metadata file, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys.
http://www.dggs.alaska.gov/metadata/dggs.ext
dggs metadata extensions