gov.noaa.csc.maps:2009_Chatham_Lidar_m1121
Chatham County, Georgia
Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS),
Coastal Services Center (CSC)
201201
2009 Chatham County Georgia Lidar
Charleston, SC
NOAA's Ocean Service, Coastal Services Center (CSC)
http://www.csc.noaa.gov/dataviewer/index.html?action=advsearch&qType=in&qFld=ID&qVal=1121
http://www.csc.noaa.gov/lidar
http://www.csc.noaa.gov
LiDAR generated point cloud acquired in spring 2009 for Chatham County, Georgia for the Metropolitan Planning Commission.
The data are classified as follows:
Class 1 = Unclassified. This class includes vegetation, buildings, noise etc.
Class 2 = Ground
Class 9 = Water
This data is for planning purposes only and should not be used for legal or cadastral purposes.
LiDAR points used in conjunction with LiDAR derived breaklines to determine a DTM surface.
Support of FEMA's Floodplain Map Modernization Program and Florida Division of Emergency Management Disaster standards.
A footprint of this data set may be viewed in Google Earth at:
ftp://ftp.csc.noaa.gov/pub/crs/beachmap/qa_docs/ga/2009_Chatham_County_Georgia_Lidar.kmz
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ground condition
Unknown
-81.395700
-80.831008
32.250903
31.713978
ISO 19115 Topic Category
elevation
None
Bathymetry/Topography
DTM
Elevation
Lidar
None
United States
Georgia
Chatham County
None
Users should be aware that temporal changes may have occurred since this data set was collected and some parts of
this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a
full awareness of its limitations.
SAGIS
Noel Perkins
Director
mailing and physical
110 East State Street
Savannah
GA
31412-8246
US
912-651-1476
912-651-1480
perkinsn@thempc.org
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.4.1420
Data covers the tile scheme provided for the county.
A visual qualitative assessment was performed in the source Lidar dataset.
Lidar acquired and processed to meet 1 m (RMSE) horizontal accuracy.
0.5
Horizontal point accuracy is a function of angular origination of the pulse;
IMU orientation; the scanner encoder and ranging function and will vary depending on the proposed point density selected for
the collection. Statistically, the error is roughly 1/3 of the illuminated foot print on the ground and is a function of the
beam divergences.
The vertical accuracy is based on the Sanborn independent collection of 20 ground survey points distributed throughout the project.
The fundamental vertical accuracy at 95 percent confidence level in open terrain tested 0.07 meters (0.25 ft).
1. Vertical accuracy: Less than 0.30 feet RMSEz = less than 0.60 feet vertical accuracy at 95% confidence level, tested in flat,
non-vegetated terrain only, employing NSSDA procedures in Reference B.
2. Validation that the data also satisfies FEMA requirements.
3. Vertical units (orthometric heights) are in US Survey Feet, NAVD88.
0.07
Based on the vertical accuracy testing conducted by Sanborn using NSSDA and FEMA methodology, vertical accuracy at the 95%
confidence level (called Accuracyz) is computed by the formula RMSEz x 1.9600. The dataset for Chatham County, Georgia satisfies
the criteria:
Countywide lidar dataset tested 0.15 m (0.49 ft) vertical accuracy at 95% confidence level in open terrain, based on open terrain
RMSEz (0.25 ft) x 1.9600.
Countywide lidar dataset tested 0.24 m (0.78 ft) vertical accuracy at 95% confidence level in all land cover categories combined,
based on consolidated RMSEz (0.40 ft) x 1.9600.
SANBORN MAP COMPANY
20090930
Airborne LiDAR Flight Details
Flight Altitude - 1100m (agl)
Repetition Rate - 93300 kHz; Scan Frequency - 44.5kz
Airspeed - 100-120 knots
Field of View - 30 degrees
Avg. Point Spacing 0.57m
Flightline Spacing - 294m
online
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ground condition
LiDAR Acquisition
Data acquisition specifications
The ABGPS, IMU, and raw Leica ALS-50 LiDAR data are integrated into the LEICA ALS post processor software. The resultant file is
in a LAS binary file format. The LAS file version 1.1 formats can be easily transferred from one file format to another. It is a
binary file format that maintains information specific to the LiDAR data (return#, intensity value, xyz, etc.). The resultant
points are produced in the geodetic coordinates referenced to the NAD83 horizontal datum and GRS80 vertical datum.
Airborne Global Positioning System Data
Inertial Measurement Unit
LiDAR Scans
2009
LiDAR Point Cloud LAS 1.1 format
Sanborn Map Company
Andrew Lucero
Sr. Project Manager
mailing and physical
1935 Jamboree Drive
Colorado Springs
CO
80920
USA
719-264-5645
719-528-5093
alucero@sanborn.com
8:00 - 5:00 MST
The unedited data are classified to facilitate the application of the appropriate feature extraction filters. A combination of
proprietary filters are applied as appropriate for the production of bare earth digital terrain models (dtms). Interactive editing
methods are applied to those areas where it is inappropriate or impossible to use the feature extraction filters, based upon the
design criteria and/or limitations of the relevant filters. These same feature extraction filters are used to produce elevation
height surfaces. The LiDAR mass points were delivered in American Society for Photogrammetry and Remote Sensing LAS 1.1 format.
The header file for each dataset is complete as define by the LAS 1.1 specification. In addition the following fields are included:
Flight Date Julian, Year, and Class. The LAS files do not include an overlap class.
The data was classified as follows:
Class 1 = Unclassified. This class includes vegetation, buildings, noise etc.
Class 2 = Ground
Class 7 = noise (outliers)
Class 9 = Water
LiDAR Point Cloud LAS 1.1 format
2009
Classified LiDAR datasets
Sanborn Map Company
Andrew Lucero
Sr. Project Manager
mailing and physical
1935 Jamboree Drive
Colorado Springs
CO
80920
USA
719-264-5645
719-528-5093
alucero@sanborn.com
8:00 - 5:00 MST
Conversion from Geodetic coordinates, NAD83 into State Plane coordinates (U.S. Survey Feet) NAD83 and conversion from ellipsoid
heights (meters) into orthometric heights (U.S. Survey Feet).
Classified LiDAR datasets
2009
Projected and tiled LiDAR datasets LAS 1.1 format
Sanborn Map Company
Andrew Lucero
Sr. Project Manager
mailing and physical
1935 Jamboree Drive
Colorado Springs
CO
80920
USA
719-264-5645
719-528-5093
alucero@sanborn.com
8:00 - 5:00 MST
Ground points were extracted from the Lidar dataset and used in conjunction with breaklines to hydrologically enforce a DTM surface
and converted to an ESRI GRID (1m pixels) using ArcGIS.
Projected and tiled LiDAR datasets
2009
ESRI GRID (1m)
Sanborn Map Company
Andrew Lucero
Sr. Project Manager
mailing and physical
1935 Jamboree Drive
Colorado Springs
CO
80920
USA
719-264-5645
719-528-5093
alucero@sanborn.com
8:00 - 5:00 MST
The NOAA Coastal Services Center (CSC) received the files in las format. The files contained lidar elevation and intensity
measurements. The data were in GA State Plane coordinates and NAVD88 (orthometric) heights in feet. CSC performed the
following processing for data storage and Digital Coast provisioning purposes:
1. The data were converted from GA State Plane coordinates to geographic coordinates.
2. The data were converted from NAVD88 (orthometric) heights in feet to GRS80 (ellipsoid) heights in meters using Geoid 03.
3. The data were filtered to remove outliers.
4. The LAS data were sorted by latitude and the headers were updated.
2012
NOAA Coastal Services Center
mailing and physical
2234 South Hobson Ave.
Charleston
SC
29405-2413
US
843-740-1200
csc.info@noaa.gov
For questions please use the form at http://www.csc.noaa.gov/contact/contactForm.htm
The NOAA National Geophysical Data Center (NGDC) received Lidar data files by ftp. The data received compressed containing LiDAR data from the NOAA Coastal Services Center. The data are currently being served via Digital Coastl at http://www.csc.noaa.gov/digitalcoast/. The data can be used to re-populate the system. The data are provided in LAS format. LAS format is an industry standard for serving LiDAR data. The data are exclusively in geographic coordinates, however, the datums used vary. Most are NAD 83, however some are in ITRF. Vertical systems include both ellipsoid (ITRF and NAD 83) and NAVD 88. For NAVD 88 values, Geiod 03 is primarily used; however, data received in NAVD 88 prior to 2003 was processed using Geoid 99.
20120213
DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
Pamela Grothe
Mailing and Physical Address
NOAA/NESDIS/NGDC E/GC1 325 Broadway
Boulder
CO
80305-3328
USA
(303) 497-6120
(303) 497-6958
(303) 497-6513
pamela.grothe@noaa.gov
7:30-5:00 Mountain
Contact Data Center
Point
0.0000001
0.0000001
Decimal degrees
North American Datum of 1983
Geodetic Reference System 80
6378137.000000
298.257222
Ellipsoid
0.01
Meters
Explicit elevation coordinate included with horizontal coordinates
LAS
GPS, IMU, and laser pulse range data
ASPRS LiDAR Data Exchange Format Standard version 1.1
X Coord
Easting Coordinate
ASPRS LiDAR Data Exchange Format Standard version 1.1
Coordinates defining the features.
Y Coord
Northing Coordinate
ASPRS LiDAR Data Exchange Format Standard version 1.1
Coordinates defining the features.
Z
Height above Sea-level
ASPRS LiDAR Data Exchange Format Standard version 1.1
Elevation above ground level in meters
Classification
Assigned Point Classification
ASPRS LiDAR Data Exchange Format Standard version 1.1
Classification
ASPRS Standard LiDAR Point Classes
Intensity
Strength of return value within a given range
ASPRS LiDAR Data Exchange Formate Standard version 1.1
0-256
LiDAR Pulse Energy
ASPRS LiDAR Data Exchange Formate Standard version 1.1
Return
The number of returns for a given pulse
ASPRS LiDAR Data Exchange Format Standard version 1.1
1-4
Return Number
ASPRS LiDAR Data Exchange Format Standard version 1.1
Scan Direction Flag
Direction the scanner mirror was traveling at the time of the output pulse
ASPRS LiDAR Data Exchange Format Standard version 1.1
0-1
A value of 1 is positive; 0 is negative
ASPRS LiDAR Data Exchange Format Standard version 1.1
Edge of Flightline
t is the last point on a given scan line before it changes direction
ASPRS LiDAR Data Exchange Format Standard version 1.1
Flag (0=false;1=true)
Indicate true if a given point is at the end of a scan
ASPRS LiDAR Data Exchange Format Standard version 1.1
ASPRS LAS Point Record Entries - binary data recorded for each point
ASPRS LAS attributes
NOAA Coastal Services Center
mailing and physical
2234 South Hobson Ave.
Charleston
SC
29405-2413
US
843-740-1200
csc.info@noaa.gov
For questions please use the form at http://www.csc.noaa.gov/contact/contactForm.htm
Downloadable Data
The data represent the results of data collection and processing for a specific Metropolitan Planning
Commission activity and indicates the general existing conditions at the time of the data collection. As such, it is only valid for
its intended use, content, time, and accuracy specifications. The user is responsible for the results of any application of the data
for other than its intended purpose. Any conclusions drawn from the analysis of this information are not the responsibility of the
Coastal Services Center or its partners.
This data can be obtained on-line at the following URL: http://www.csc.noaa.gov/lidar
The data set is dynamically generated based on user-specified parameters.
DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
Pamela Grothe
Mailing and Physical Address
NOAA/NESDIS/NGDC E/GC1 325 Broadway
Boulder
CO
80305-3328
USA
(303) 497-6120
(303) 497-6958
(303) 497-6513
pamela.grothe@noaa.gov
7:30-5:00 Mountain
Contact Data Center
Disclaimer While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
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.
20120213
20120213
20130213
NOAA Coastal Services Center
mailing and physical
2234 South Hobson Ave.
Charleston
SC
29405-2413
US
843-740-1200
csc.info@noaa.gov
For questions please use the form at http://www.csc.noaa.gov/contact/contactForm.htm
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998