U.S. Geological Survey
2008
EAARL Coastal Topography-St. John, U.S. Virgin Islands 2003: First Surface
first
remote-sensing image
U.S. Geological Survey Data Series
406
Saint Petersburg, FL
U.S. Geological Survey
http://pubs.usgs.gov/ds/406/
A first surface elevation map (also known as a Digital Elevation Model, or DEM) of a portion of St. John, U.S. Virgin Islands was produced from remotely sensed, geographically referenced elevation measurements cooperatively by the U.S. Geological Survey (USGS), National Aeronautics and Space Administration (NASA), and National Park Service (NPS). Elevation measurements were collected over the area using the NASA Experimental Advanced Airborne Research Lidar (EAARL), a pulsed-laser ranging system mounted onboard an aircraft to measure ground elevation, vegetation canopy, and coastal topography. The system uses high-frequency laser beams directed at the Earth's surface through an opening in the bottom of the aircraft's fuselage. The laser system records the time difference between emission of the laser beam and the reception of the reflected laser signal in the aircraft. The plane travels over the target area at approximately 50 meters per second at an elevation of approximately 300 meters. The EAARL, developed by NASA at Wallops Flight Facility in Virginia, measures ground elevation with a vertical resolution of 15 centimeters. A sampling rate of 3 kilohertz or higher results in an extremely dense spatial elevation dataset. Over 100 kilometers of coastline can be surveyed easily within a 3- to 4-hour mission. When subsequent elevation maps for an area are analyzed, they provide a useful tool to make management decisions regarding land development.
For more information on Lidar science and the Experimental Advanced Airborne Research Lidar (EAARL) system and surveys, see http://ngom.usgs.gov/dsp/overview/index.php and http://ngom.usgs.gov/dsp/tech/eaarl/index.php .
The purpose of this project was to produce a highly detailed and accurate first surface elevation map of St. John, U.S. Virgin Islands.
Raw Lidar data are not in a format that is generally usable by Park Service resource managers and scientists for scientific analysis. Converting dense Lidar elevation data into a readily usable format without loss of essential information requires specialized processing. The U.S. Geological Survey converts raw Lidar data into a GIS-compatible map product to be provided to National Park Service GIS specialists, managers, and scientists. The primary tool used in the conversion process is Airborne Lidar Processing System (ALPS), a multi-tiered processing system developed by a USGS-NASA collaborative project. Specialized processing algorithms are used to convert raw waveform Lidar data acquired by the EAARL to georeferenced spot (x,y,z) returns for "first surface" and "bare earth" topography. These data are represented in the WGS84 coordinate system, with an ITRF reference system. Each file contains data located in a 2-km by 2-km tile, where the upper-left bound can be assessed quickly through the file name. The first 3 numbers in the file name represent the left-most UTM easting coordinate (e###000) in meters, the next 4 numbers represent the top-most UTM northing coordinate (n####000) in meters, and the last 2 numbers (##) represent the UTM zone in which the tile is located (for example, fs_e123_n4567_20).The development of custom software for creating these data products has been supported by the USGS CMG Program's Decision Support for Coastal Parks, Sanctuaries, and Preserves Project. Processed data products are used by the USGS CMG Program's National Assessments of Coastal Change Hazards Project to quantify the vulnerability of shorelines to coastal change hazards such as severe storms, sea-level rise, and shoreline erosion and retreat.
20030421
20030423
20030430
20030502
20030614
20030617
ground condition
None planned
-64.816667
-64.633333
18.4
18.3
USGS Metadata Identifier
USGS:9806d7e5-0ad1-4b94-9699-007bc202b871
ISO Topic Keywords 19115
elevation
http://remotesensing.usgs.gov
Airborne Lidar Processing System
ALPS
DEM
Digital Elevation Model
EAARL
Experimental Advanced Airborne Research Lidar
laser altimetry
Lidar
remote sensing
Data Categories for Marine Planning
distributions
bathymetry and elevation
Marine Realms Information Bank (MRIB) Keywords
altimetry
topographic mapping
USGS Thesaurus
LIDAR
topography
digital elevation models
http://nationalmap.gov
St. John
U.S. Virgin Islands
http://lidar.cr.usgs.gov
First Surface
http://www.esri.com/news/arcuser/1104/temporal.html
2003
None
The U.S. Geological Survey, National Park Service, and National Aeronautics and Space Administration request to be acknowledged as originators of this dataset in future products or derivative research.
Amar Nayegandhi
Jacobs Technology, U.S. Geological Survey, FISC, St. Petersburg, FL
Computer Scientist
mailing and physical address
600 4th Street South
Saint Petersburg
Florida
33701
USA
727-803-8747 (x3026)
727-803-2031
anayegandhi@usgs.gov
M-F, 8:00-5:00 EST
http://pubs.usgs.gov/ds/406/html/images/STJN.jpg
EAARL Coastal Topography-St. John, U.S. Virgin Islands 2003: First Surface
JPG
Acknowledgment of the U.S. Geological Survey, Florida Integrated Science Center, as a data source would be appreciated in products developed from these data, and such acknowledgment as is standard for citation and legal practices for data source is expected. 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.
Unclassified
Unclassified
None
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.2.1350
The expected accuracy of the measured variables is as follows: attitude within 0.07 degree, 3 cm nominal ranging accuracy, and vertical elevation accuracy of +/-15 cm for the topographic surface. Quality checks are built into the data-processing software.
Each file contains data located in a 2-km by 2-km tile, where the upper-left bound can be assessed quickly through the file name. The first 3 numbers in the file name represent the left-most UTM easting coordinate (e###000) in meters, the next 4 numbers represent the top-most UTM northing coordinate (n####000) in meters, and the last 2 numbers (##) represent the UTM zone in which the tile is located (for example, fs_e123_n4567_20).
Several regions of the dataset are labeled as "No Data", which corresponds to a cell value of -32767 m in the GeoTIFF file. These "No Data" areas are a result of the survey not covering a particular region, optical water depth of greater than 1.5 Secchi disc depths, or the manual removal of Lidar processing artifacts.
Raw elevation measurements have been determined to be within 1-meter horizontal accuracy.
Elevations of the DEM are vertically consistent with the point elevation data, +/-15 cm.
U.S. Geological Survey
2008
EAARL Coastal Topography-St. John, U.S. Virgin Islands 2003: First Surface
first
remote-sensing image
U.S. Geological Survey Data Series
406
Saint Petersburg, FL
U.S. Geological Survey
Point elevation measurements collected by the EAARL sensor.
20030421
20030423
20030430
20030502
20030614
20030617
data collection
None
None
The data are collected using a Cessna 310 aircraft. The NASA Experimental Advanced Airborne Research Lidar (EAARL) laser scanner collects the data using a green (532-nm) raster scanning laser, while a digital camera acquires a visual record of the flight. The data are stored on hard drives and archived at the U.S. Geological Survey office in St. Petersburg, FL, and the NASA office at Wallops Flight Facility in Virginia. The navigational data are processed at Wallops Flight Facility. The navigational and raw data are then downloaded into the Airborne Lidar Processing System (ALPS). Data are converted from units of time to x,y,z points for elevation. The derived surface data can then be converted into raster data (GeoTIFFs).
20080729
Amar Nayegandhi
Jacobs Technology, U.S. Geological Survey, FISC, St. Petersburg, FL
Computer Scientist
mailing and physical address
600 4th Street South
Saint Petersburg
Florida
33701
USA
727-803-8747 (x3026)
727-803-2031
anayegandhi@usgs.gov
M-F, 8:00-5:00 EST
Metadata imported into ArcCatalog from XML file.
20080729
Xan Yates
U.S. Geological Survey, FISC, St. Petersburg, FL
Metadata Specialist
mailing and physical address
600 4th Street South
Saint Petersburg
Florida
33701
USA
727-803-8747 (x3086)
M-F, 8:00-5:00 EST
Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog.
20170124
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.
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
Tiling Index
Raster
Pixel
2001
2001
1
Universal Transverse Mercator
20
0.999600
-63.000000
0
500000.000000
0
row and column
1.000000
1.000000
meters
D_WGS_1984
WGS_1984
6378137.000000
298.257224
D_WGS_1984
0.15 m
meters
Attribute values
Each pixel of the encoded GeoTIFF has an explicit elevation value associated with it. The GeoTIFF grid is encoded with a 1-meter resolution.
The variables measured by EAARL are distance between aircraft and GPS satellites (m), attitude information (roll, pitch, heading in degrees), scan angle (degrees), second of the epoch (sec), and 1-ns time-resolved return intensity waveform (digital counts). Z value is referenced to orthometric elevations derived from National Geodetic Survey Geoid Model, GEOID03.
U.S. Geological Survey
Project Manager
Project Manager
mailing and physical address
600 4th Street South
Saint Petersburg
Florida
33701
USA
727-803-8747 (x3026)
M-F, 8:00-5:00 EST
DS 406
This DVD publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
GeoTIFF
2008
GeoTIFF
http://pubs.usgs.gov/ds/406/data_files/fs/
Data can be downloaded via the World Wide Web (WWW)
DVD
DVD
Vary
Contact U.S. Geological Survey.
Vary
Contact U.S. Geological Survey for details.
20211109
United States Geological Survey, St. Petersburg Coastal and Marine Science Center
SPCMSC Data Management Group
mailing and physical address
600 4th Street South
St. Petersburg
Florida
33701
US
727-502-8000
gs-g-spcmsc_data_inquiries@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998