1996-2000 NOAA/USGS/NASA Airborne LiDAR Assessment of Coastal Erosion (ALACE) Project for the US CoastlinespatialRepresentationInfo
language: eng; USA
characterSet: (MD_CharacterSetCode) utf8
hierarchyLevel: (MD_ScopeCode) dataset
contact: Mike Sutherland(author) (CI_ResponsibleParty)
role: (CI_RoleCode) author
metadataStandardName: ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
metadataStandardVersion: ISO 19115-2:2009(E)
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geometricObjectType: (MD_GeometricObjectTypeCode) point
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code: Ellipsoid in Meters
codeSpace: Local Vertical Reference
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title: 1996-2000 NOAA/USGS/NASA Airborne LiDAR Assessment of Coastal Erosion (ALACE) Project for the US Coastline
dateType: (CI_DateTypeCode) publication
citedResponsibleParty: NOAA CSC (originator)
citedResponsibleParty: NOAA CSC (publisher) (CI_ResponsibleParty)
role: (CI_RoleCode) publisher
presentationForm: (CI_PresentationFormCode) imageDigital
abstract: This data set includes data collected from 1996-2000 and covers the states of AL,FL,LA,MS,DE,MD,VA,CT,MA,ME,NH, NJ,NY,RI,NC,SC,GA,CA OR,WA,TX OH,PA. Laser beach mapping uses a pulsed laser ranging system mounted onboard an aircraft to measure ground elevation and coastal topography. The laser emits laser beams at high frequency and is directed downward at the earth's surface through a port 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 aircraft travels over the beach at approximately 60 meters per second while surveying from the low water line to the landward base of the sand dunes.
purpose: This data was collected as part of an effort to map beach topography efficiently and cheaply.
credit: Airborne Topographic Mapper LIDAR data were collected in partnership with the National Oceanic and Atmospheric Administration (NOAA) Coastal Services Center, the NASA Wallops Flight Facility, the U. S. Geological Survey (USGS) Center for Coastal and Regional Marine Geology, and the NOAA Aircraft Operations Center.
status: (MD_ProgressCode) completed
pointOfContact: NOAA CSC (pointOfContact) (CI_ResponsibleParty)
role: (CI_RoleCode) pointOfContact
maintenanceAndUpdateFrequency: (MD_MaintenanceFrequencyCode) notPlanned
keyword: digital elevation model
type: (MD_KeywordTypeCode) theme
keyword: U.S. Coastline
keyword: North Carolina
keyword: South Carolina
keyword: New Hampshire
keyword: New Jersey
keyword: New York
keyword: Rhode Island
type: (MD_KeywordTypeCode) place
resourceConstraints: Lidar Use Limitation
resourceConstraints: NOAA Legal Statement
spatialRepresentationType: (MD_SpatialRepresentationTypeCode) vector
language: eng; USA
topicCategory: (MD_TopicCategoryCode) elevation
supplementalInformation: This data set was collected with a LIDAR (LIght Detection And Ranging) instrument designed and developed by the Observational Sciences Branch (OSB) of NASA at the Wallops Flight Facility in Virginia. The instrument, originally designed for mapping ice sheets in Greenland, is called the Airborne Topographic Mapper or ATM. The ATM II (the latest version), operates with a Spectra Physics laser transmitter, which provides a 7 nanoseconds long, 250 microjoules pulse at a frequency-doubled wavelength of 523 nanometers in the blue-green spectral region. The laser transmitter can function at pulse rates from 2 to 10 kilohertz (kHz). The laser system with a separate cooling unit weighs approximately 45 kilograms (kg) and requires approximately 15 amperes of power at 115 volts. The transmitted laser pulse is reflected to the surface of the earth with the aid of a small folding mirror mounted on the back of a secondary mirror of a rotating scan mirror assembly mounted directly in front of the telescope. The scan mirror, which is rotated at 20 hertz, is comprised of a section of round aluminum stock, machined to a specific off-nadir angle. A scan mirror with the off-nadir angle of 15 degrees was utilized, producing an elliptical scan pattern with a swath width equal to 50 percent of the approximately 700-meter aircraft altitude. The reflected laser pulse is transmitted to a photo-multiplier assembly that consists of a lens, a narrow bandpass filter, and a single photomultiplier tube. Note: The Spatial Reference section of this document may lack fully FGDC-compliant information regarding projection parameters (i.e., Central meridian, false Northing, etc.). The State Plane or UTM Zone will be supplied, and the corresponding parameters can be found in Appendix C of: Snyder, John, 1987, Map Projections, a Working Manual (U.S. Geological Survey Professional Paper 1395): Washington, U.S. Government Printing Office.
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distributorContact: NOAA CSC(distributor) (CI_ResponsibleParty)
role: (CI_RoleCode) distributor
orderingInstructions: The National Geophysical Data Center serves as the archive for this LIDAR data. NGDC should only be contacted for this data if it cannot be obtained from NOAA Coastal Services Center.
distributorContact: Mike Sutherland
orderingInstructions: The National Geophysical Data Center serves as the archive for this LIDAR dataset. NGDC should only be contacted for the data if it cannot be obtained from NOAA Coastal Services Center.
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level: (MD_ScopeCode) dataset
nameOfMeasure: Horizontal Positional Accuracy Report
evaluationMethodDescription: The ATM LIDAR elevation points are known to be horizontally accurate to +/- 0.8 meters at an aircraft altitude of 700 meters.
nameOfMeasure: Vertical Positional Accuracy Report
evaluationMethodDescription: The ATM LIDAR elevation measurements have been found to be within +/- 15 centimeters of each other in successive and overlapping passes of the same area. In comparisons of LIDAR data for a small geographic region with various ground surveys the differences are between +/- 15 to 20 centimeters. The accuracy of the majority of the data is estimated to be consistent with the above stated results. At this time, there has been no large scale verification of the data.
evaluationMethodDescription: All elevation data points that appeared to be within a reasonable vertical range were retained, and other points were thrown away. This filtering process was performed 'by eye'.
measureDescription: Not applicable.
description: The vertical values in this data set have been filtered through visual inspection to find abnormally high and abnormally low values. In addition, this data was processed using a spatial filtering program that identifies and discards outlier elevation measurements. This program reads each elevation measurement within a file and identifies "spatially close" points (i.e. those neighboring points within a fixed radius of the point). The mean and standard deviation is calculated using the elevations of these points. If the elevation difference from the mean of the point under consideration is more than 2 standard deviations and greater than a defined distance the point is discarded.
description: The NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp transfer from the NOAA Coastal Services Center. The data are currently being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/. The data can be used to re-populate the system. The data are archived in LAS or LAZ format. The LAS format is an industry standard for LiDAR data developed by the American Society of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless compressed version of LAS developed by Martin Isenburg (http://www.laszip.org/). The data are exclusively in geographic coordinates (either NAD83 or ITRF94). The data are referenced vertically to the ellipsoid (either GRS80 or ITRF94), allowing for the ability to apply the most up to date geoid model when transforming to orthometric heights.
individualName: Pamela Grothe
organisationName: DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
contactInstructions: Contact Data Center
role: (CI_RoleCode) processor
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maintenanceAndUpdateFrequency: (MD_MaintenanceFrequencyCode) annually
maintenanceNote: This metadata was automatically generated from the FGDC Content Standards for Digital Geospatial Metadata standard (version FGDC-STD-001-1998) using the 2013-01-04 version of the FGDC RSE to ISO 19115-2 for LiDAR transform.
maintenanceNote: Translated from FGDC 2013-05-07T13:20:10.555-06:00
maintenanceNote: Last Metadata Review Date: 2011-11-19