U.S. Geological Survey
2015
Assateague Island Back-Island Shoreline Points Extracted from Orthoimagery, 1989 - 2013
vector digital data
U.S. Geological Survey Data Series
928
St. Petersburg, Fla.
U.S. Geological Survey
https://pubs.usgs.gov/ds/0928/downloads/back_island_shoreline_points.zip
Assessing the physical change to shorelines and wetlands is critical in determining the resiliency of wetland systems that protect adjacent habitat and communities. The wetland and back-barrier shorelines of Assateague Island, located in Maryland and Virginia, changed as a result of wave action and storm surge that occurred during Hurricane Sandy, which made landfall on October 29, 2012. The impact of Hurricane Sandy will be assessed and placed in its historical context to understand the future vulnerability of wetland systems.
Making these assessments will rely on data extracted from current and historical resources such as maps, aerial photographs, satellite imagery, and lidar elevation data, which document physical changes over time.
This USGS Data Series publication includes several open-ocean shorelines, back-island shorelines, back-island shoreline points, sand area polygons, and sand lines for Assateague Island that were extracted from orthoimagery (orthoaerial photography) dated from April 12, 1989 to September 5, 2013.
This dataset consists of points that were digitized at the intersection of the back-island shoreline and a set of transects spaced at 20 meter (m) intervals. The transects, asis_transects_ln_20m_utm18.shp, are included in this Data Series publication and can be accessed via the Data Download page. Only one back-island shoreline/transect intersection point was digitized per transect.
Orthoimagery of Assateague Island were acquired in digital format from U.S. Department of Agriculture (USDA), U.S. Geological Survey (USGS) and Virginia Geographic Information Network (VGIN) courtesy of the Commonwealth of Virginia.
The following list provides additional details about the orthoimagery used. The back-island shoreline points for all dates have been compiled into one dataset (shapefile) named asis_bshrln_1989_2013_transect_guided.shp. The orthoimage date for each line is included in the shapefile attribute table Date_ field.
Date State Type Source Resolution
198904129(1) MD DOQQ USGS 1 meter (m)
19940320 VA DOQQ USGS 1 m
20041105 VA NAIP USDA 2 m
20050608 VA NAIP USDA 2 m
20050615 MD NAIP USDA 1 m
20060528 VA NAIP USDA 2 m
20060701 MD NAIP USDA 2 m
20070622 MD NAIP USDA 1 m
20080525 VA NAIP USDA 1 m
20090626 MD NAIP USDA 1 m
20090726 VA NAIP USDA 1 m
20090807 VA NAIP USDA 1 m
20110530 VA NAIP USDA 1 m
20110602 MD NAIP USDA 1 m
20120512 VA NAIP USDA 1 m
20130315 VA VBMP VGIN(2) 1 m(3)
20130905 MD NAIP USDA 1 m
DOQQ Digital Orthophoto Quarter Quads
NAIP National Agriculture Imagery Program
VBMP Virginia Base Mapping Program
(1)Color Infrared orthoimagery; all others are natural color.
(2)Imagery courtesy of the Commonwealth of Virginia.
(3)Resampled from 1-foot resolution imagery.
These data were extracted from orthoimagery to document the changes in Assateague Island's back-island shoreline due to Hurricane Sandy and over time from 1989 to 2013.
These data will aid in developing an assessment of the physical change in wetlands due to wave action and storm surge from Hurricane Sandy and in determining the resiliency of wetland systems that protect adjacent habitat and communities.
19890412
20130905
ground condition
None planned
-75.407358
-75.096357
38.325681
37.865184
USGS Metadata Identifier
USGS:18596238-93f6-4687-81a5-3284a781809f
None
aerial photography
remote sensing
orthoimagery
orthophotography
shoreline
wetlands
erosion
Global Change Master Directory (GCMD)
LAND SURFACE > LAND USE/LAND COVER > LAND COVER
OCEAN > COASTAL PROCESSES > BARRIER ISLANDS
COASTAL PROCESSES > BEACHES
DOI/USGS/CMG > COASTAL AND MARINE GEOLOGY, U.S. GEOLOGICAL SURVEY, U.S. DEPARTMENT OF INTERIOR
None
Assateague Island
Maryland
Virginia
United States
National Seashore
Worcester
Accomack
General
1989
1994
2004
2005
2006
2007
2008
2009
2011
2012
2013
None.
Variability in the quality of the imagery from one date to another, from one image to another taken on the same date, and from one part of an image to another part of the same image, exists due to many factors including variation in sun angle, atmospheric conditions, season, reflectivity of the earth surface, camera angle, camera lens, camera settings, film sensitivity, water turbidity, water depth, tide level, waves, and error in image rectification. No adjustments were made to account for tide level.
Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Coastal and Marine Geology Program as the originator of these data in future products or derivative research.
U.S. Geological Survey
Kristy Guy
mailing and physical
600 4th St. S.
St. Petersburg
FL
33701
USA
727-502-8000
727-502-8181
kguy@usgs.gov
Monday through Friday 9:00 AM to 5:00 PM (Eastern Time)
Acknowledgment of the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Coastal and Marine Geology Program as a data source would be appreciated in products developed from these data, and such acknowledgment as is standard for citation and legal practices. Sharing of new data layers developed directly from these data would also be appreciated by the U.S. Geological Survey staff. Users should be aware that comparisons with other datasets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in photointerpretation, mapping conventions, and digital processes over time. These data are not legal documents and are not to be used as such.
Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.2.2.3552.
None of the orthoimagery datasets covered the entire island and inconsistencies due to differences in image quality should be expected. No adjustments were made for varying tide levels. The points were digitized at a scale of approximately 1:2,000.
Complete.
The horizontal accuracy of the data are unknown.
USGS
2014
USGS DOQQ Orthoimagery
orthophotography
http://earthexplorer.usgs.gov/
USGS
online
19890412
19940320
ground condition
USGS Orthoimagery
This data source was used to hand-digitize back-island shoreline points.
U.S. Department of Agriculture (USDA)
2014
USDA NAIP Orthoimagery
orthophotography
http://datagateway.nrcs.usda.gov/GDGOrder.aspx
USDA
online
20050608
20130905
ground condition
USDA Orthoimagery
This data source was used to hand-digitize back-island shoreline points.
Virginia Geographic Information Network (VGIN)
2013
VGIN Orthoimagery
orthophotography
Richmond, VA
VGIN
digital hard drive
20130315
20130315
ground condition
VGIN Orthoimagery
This data source was used to hand-digitize back-island shoreline points.
Using ArcMap 10.1 and a scale of approximately 1:2000, shore-normal transect lines spaced 20 m apart were laid over the orthoimages. The points were hand-digitized at the intersections of the apparent back-island shoreline and the transect lines. Only one back-island shoreline/transect line intersection point was digitized per transect line. The orthoimagery date was added to the Date_ field in the shapefile attribute table.
USGS Orthoimagery
USDA Orthoimagery
VGIN Orthoimagery
2014
asis_bshrpts_1989_2013_transect_guided.shp
USGS
mailing and physical
600 4th St. S.
St. Petersburg
FL
33701
USA
727-502-8000
727-502-8181
Monday through Friday 8:00 AM to 5:00 PM (Eastern Time)
If unable to reach the contact by telephone, please leave a voice message.
Added keywords section with USGS persistent identifier as theme keyword.
20201013
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
Entity point
19124
Universal Transverse Mercator
18
0.9996
-75.0
0.0
500000.0
0.0
coordinate pair
0.6096
0.6096
meter
North American Datum of 1983
Geodetic Reference System 1980
6378137.0
298.257222101
asis_bshrpts_1989_2013_transect_guided.shp
Assateague Island back-island shoreline points digitized from orthoimagery.
USGS
FID
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Shape
Feature geometry.
Esri
Coordinates defining the features.
Date_
Date of orthoimage source.
USGS
Date in month, day, year that the image was collected.
Kristy Guy
U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, Fla.
GIS/RS Analyst
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
USA
727-502-8000
Monday-Friday, 9:00-5:00 Eastern Time
DS 928
Although these data were processed successfully on a computer system at the 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. The USGS shall not be held liable for improper or incorrect use of the data described and/or contained herein. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
ArcGIS shapefile
https://pubs.usgs.gov/ds/0928/downloads/back_island_shoreline_points.zip
None if obtained online; otherwise prices vary.
Publications are available from USGS Information Services, Box 25286, Federal Center, Denver, CO 80225-0046 (telephone: 1-888-ASK-USGS, e-mail: infoservices@usgs.gov).
20201013
USGS
Kristy Guy
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
727-502-8000
727-502-8181
kguy@usgs.gov
Monday through Friday 9:00 AM to 5:00 PM (Eastern Time)
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
None.
None.
None.
Unclassified
NONE