U.S. Geological Survey
2017
Digital Shoreline Analysis System version 4.3 Transects with Long-Term Linear Regression Rate Calculations for Mississippi
1
vector digital data
data release
DOI:10.5066/F78P5XNK
Woods Hole Coastal and Marine Science Center, Woods Hole, MA
U.S. Geological Survey, Coastal and Marine Geology Program
https://doi.org/10.5066/F78P5XNK
https://www.sciencebase.gov/catalog/item/582ca4d6e4b04d580bd37925
https://www.sciencebase.gov/catalog/file/get/582ca4d6e4b04d580bd37925
E.A. Himmelstoss
M.G. Kratzmann
E.R. Thieler
2017
National Assessment of Shoreline Change— A GIS compilation of Updated Vector Shorelines and Associated Shoreline Change Data for the Gulf of Mexico Coast
1
data release
DOI:10.5066/F78P5XNK
Reston, VA
U.S. Geological Survey
https://doi.org/10.5066/F78P5XNK
https://www.sciencebase.gov/catalog/item/58055db4e4b0824b2d1c1ee2
Sandy ocean beaches are a popular recreational destination, often surrounded by communities containing valuable real estate. Development is on the rise despite the fact that coastal infrastructure is subjected to flooding and erosion. As a result, there is an increased demand for accurate information regarding past and present shoreline changes. 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 open-ocean 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.
This dataset consists of long-term (~150 years) shoreline change rates for the Mississippi coastal region from Petit Bois Island to Cat Island. 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. Long-term rates of shoreline change were calculated using a linear regression rate based on available shoreline data for a minimum 50-year period. 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 long-term rates.
2017
publication date
None planned
-89.099293
-88.403482
30.252967
30.189507
USGS Metadata Identifier
USGS:582ca4d6e4b04d580bd37925
None
Long-Term Shoreline Change Rate
Shoreline
Historic Shoreline
Erosion
Accretion
Linear Regression Rate
Transect
Digital Shoreline Analysis System
DSAS
U.S. Geological Survey
USGS
Coastal and Marine Geology Program
CMGP
Woods Hole Coastal and Marine Science Center
WHCMSC
National Assessment of Shoreline Change Project
ISO 19115 Topic Category
oceans
environment
geoscientificInformation
Marine Realms Information Bank (MRIB) Keywords
effects of coastal change
coastal processes
shoreline accretion
shoreline erosion
USGS Thesaurus
coastal processes
erosion
shoreline accretion
None
Mississippi
MS
Petit Bois Island
Horn Island
Ship Island
Cat Island
Gulf of Mexico
United States
North America
None
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.
U.S. Geological Survey
E.A. Himmelstoss
mailing and physical address
384 Woods Hole Road
Woods Hole
MA
02543-1598
USA
508-548-8700
508-457-2310
ehimmelstoss@usgs.gov
Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.0.4.4000
Robert A. Morton
Tara L. Miller
Laura J. Moore
2004
National Assessment of Shoreline Change: Part 1 Historical Shoreline Changes and Associated Coastal Land Loss along the U.S. Gulf of Mexico
Open-File Report
2004-1043
Reston, VA
U.S. Geological Survey
https://pubs.usgs.gov/of/2004/1043/
E.R. Thieler
E.A. Himmelstoss
J.L. Zichichi
A. Ergul
2009
Digital Shoreline Analysis System (DSAS) version 4.0 - An ArcGIS extension for calculating shoreline change
Open-File Report
2008-1278
Reston, VA
U.S. Geological Survey
Current version of software at time of use was 4.3
https://woodshole.er.usgs.gov/project-pages/DSAS/version4/
https://woodshole.er.usgs.gov/project-pages/DSAS/
E.A. Himmelstoss
M.G. Kratzmann
E.R. Thieler
2017
National Assessment of Shoreline Change: Summary Statistics for Updated Vector Shorelines and Associated Shoreline Change Data for the Gulf of Mexico and Southeast Atlantic Coasts
Open-File Report
2017-1015
Reston, VA
U.S. Geological Survey
https://doi.org/10.3133/ofr20171015
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 long-term shoreline change rates for the region. Additional transects may have been generated but did not intersect the minimum requirement of three shorelines, one of which must be the modern (lidar-derived or 1990s) shoreline, to calculate long-term rates for a minimum 50-year period.
Transect features generated using DSAS v4.3 in ArcMap v10.0. Parameters Used: baseline layer=MS_baseline, baseline group field=NULL, transect spacing=50 meters, transect length=1500 meters, cast direction=AUTO-DETECT, baseline location=offshore, cast method=smoothed, smoothing distance=8000 meters, flip baselines=not selected. For additional details on these parameters, please see the DSAS help file distributed with the DSAS software, or visit the website at: https://woodshole.er.usgs.gov/project-pages/DSAS/version4/
This process step and all subsequent process steps were performed by the same person: E.A. Himmelstoss.
20130705
E.A. Himmelstoss
U.S. Geological Survey
mailing address
384 Woods Hole Road
Woods Hole
MA
02543-1598
USA
508-548-8700 x2262
508-457-2310
ehimmelstoss@usgs.gov
Some transects were manually edited for length, moved, or deleted in an edit session using standard editing tools in ArcMap v10.0.
20130705
Rate calculations performed using DSAS v4.3 in ArcMap v10.0 where at least three shorelines were present. Shoreline uncertainty table added to ArcMap project (MS_shorelines_uncertainty.dbf) and used by DSAS to apply bias-correction to distance measurements established by transects. Parameters Used: shoreline layer=MS_shorelines, shoreline date field=Date_, shoreline uncertainty field name=Uncy, the default uncertainty=10.8 meters, shoreline intersection parameters=closest, stats calculations=[Linear Regression Rate (LRR)], shoreline threshold=3, confidence interval=90%, Output rate table name=MS_LT_rates_20130705_161450.
20130705
Shoreline rates table (MS_LT_rates_20130705_161450.dbf) was joined to the transect feature class in ArcMap v10.0 by right-clicking on the transect layer > joins and relates > join > join attributes from a table. Parameters: join field - Object ID; table to join - MS_LT_rates_20130705_161450; field in table: TransectID; join options - keep only matching records.
20130705
The joined transect feature class was exported to a shapefile in ArcMap v10.0 by right-clicking the transect layer > data > export data, permanently linking the joined rate fields to the transect attribute table.
20130705
Any transects that did not cross the lidar shoreline were deleted using standard editing tools in ArcMap v10.0.
20130705
A quality check was performed on any transects that intersected only three shorelines to be sure the 50-year span for long term rates was covered and that a modern (lidar) shoreline was present. A frequency table was created in ArcToobox v10 > Analysis Tools > Statistics > Frequency. The output frequency table was used to identify any transects with a count value of 3. If the long term rate criteria were not met, the transect was deleted.
20130705
The exported transect shapefile was projected in Esri's ArcToolbox (v10.0) > Data Management Tools > Projections and Transformations > Project. Parameters: input projection - UTM zone 16N (WGS 1984); output projection = geographic coordinates (WGS84); transformation = none.
2015
Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog.
20170825
U.S. Geological Survey
Alan O. Allwardt
Contractor -- Information Specialist
mailing and physical address
2885 Mission Street
Santa Cruz
CA
95060
831-460-7551
831-427-4748
aallwardt@usgs.gov
Added keywords section with USGS persistent identifier as theme keyword.
20200810
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
978
0.000001
0.000001
Decimal degrees
D_WGS_1984
WGS_1984
6378137.000000
298.257224
MS_LT_rates
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.
U.S. Geological Survey
FID
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Shape
Feature geometry.
Esri
Coordinates defining the features.
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 long-term results output table calculated by DSAS.
U.S. Geological Survey
Sequential unique whole numbers that are automatically generated.
BaselineID
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.
U.S. Geological Survey
1
unlimited
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
0
unlimited
ProcTime
Assigned by DSAS automatically to record the date and time a transect was processed.
U.S. Geological Survey
no value (when transect was manually created by user)
unlimited (values based on time and date of automatic generation)
Autogen
Assigned by DSAS to indicate whether or not a transect was automatically created by DSAS (1= transect was auto generated by DSAS; blank or 0=transect was not auto-generated).
U.S. Geological Survey
blank or 0
1
StartX
Assigned by DSAS automatically to record the X coordinate of the beginning of the transect in meter units. If a transect position has been adjusted during the editing process, the coordinate in the attribute table is not updated automatically. This field was manually updated using Data East XTools v.10.2 to reflect the new position of any adjusted transects.
U.S. Geological Survey
Values based on data set extent.
StartY
Assigned by DSAS automatically to record the Y coordinate of the beginning of the transect in meter units. If a transect position has been adjusted during the editing process, the coordinate in the attribute table is not updated automatically. This field was manually updated using Data East XTools v.10.2 to reflect the new position of any adjusted transects.
U.S. Geological Survey
Values based on data set extent.
EndX
Assigned by DSAS automatically to record the X coordinate of the end of the transect in meter units. If a transect position has been adjusted during the editing process, the coordinate in the attribute table is not updated automatically. This field was manually updated using Data East XTools v.10.2 to reflect the new position of any adjusted transects.
U.S. Geological Survey
Values based on data set extent.
EndY
Assigned by DSAS automatically to record the Y coordinate of the end of the transect in meter units. If a transect position has been adjusted during the editing process, the coordinate in the attribute table is not updated automatically. This field was manually updated using Data East XTools v.10.2 to reflect the new position of any adjusted transects.
U.S. Geological Survey
Values based on data set extent.
Azimuth
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 not updated automatically. This field was manually updated using ArcToolbox > Spatial Statistics Tools > Measuring Geographic Distributions > Linear Directional Mean to reflect the new azimuth of any adjusted transects (lines were calculated individually).
U.S. Geological Survey
0
360
degrees
SHAPE_Leng
Length of feature in meter units (UTM zone 16N, WGS 84).
Esri
1499.999906
2163.628698
meters
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
Positive real numbers that are automatically generated.
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
-13.02
9.09
meters per year
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
0.43
285.73
meters
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
0.082
17.542
meters
The entity and attribute information provided here describes the tabular data associated with the dataset. Please review the individual attribute descriptions for detailed information. All calculations for length are in meter units and were based on the UTM zone 16N (WGS 1984) projection.
U.S. Geological Survey
U.S. Geological Survey
mailing and physical address
Denver Federal Center
Building 810
MS 302
Denver
CO
80225
USA
1-888-275-8747
sciencebase@usgs.gov
Neither the U.S. Government, the Department of the Interior, nor the USGS, 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 information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Shapefile
ArcGIS 10.0
Esri polyline shapefile
These files (.cpg, .dbf, .prj, .sbn, .sbx, .shp, .shp.xml, 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 compliant metadata.
no compression applied
0.348
https://www.sciencebase.gov/catalog/file/get/582ca4d6e4b04d580bd37925
https://www.sciencebase.gov/catalog/item/582ca4d6e4b04d580bd37925
https://www.sciencebase.gov/catalog/item/58055db4e4b0824b2d1c1ee2
https://doi.org/10.5066/F78P5XNK
The first link downloads the contents of the data page as a zip file, the second link is to the landing page of the data, the third and fourth links are to the main landing page of the data release.
None
These data are available in a polyline shapefile format. The user must have software to read and process the data components of a shapefile.
20200810
E.A. Himmelstoss
U.S. Geological Survey
mailing address
384 Woods Hole Road
Woods Hole
MA
02543-1598
USA
508-548-8700 x2262
508-547-2310
ehimmelstoss@usgs.gov
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
local time