49967
2008 South Carolina Lidar: Fairfield County
sc2008_fairfield_m503_metadata
Data Set
Published / External
49401
Lidar - partner (no harvest)
Project
Completed
2009
The project area is composed of 16 counties in the State of South Carolina - Cherokee, Union, Laurens,
Greenwood, Newberry, Chester, Fairfield, Lancaster, Chesterfield, Marlboro, Darlington, Dillon, Marion,
Williamsburg, Clarendon, and Orangeburg. This metadata file is for the lidar county deliverables for
Fairfield County, SC.
The project area consists of approximately 10,194 square miles including a buffer of 50 feet along the edges of the project
area and an additional buffer in some areas. The project design of the lidar data acquisition was developed to
support a nominal post spacing of 1.4 meters. The Fugro EarthData, Inc. acquisition team of Fugro Horizons, Inc.
and North West Group acquired 721 flight lines in 44 lifts from January 15, 2008 through February 10, 2008. The
data was divided into 5000' by 5000' foot cells that serve as the tiling scheme. Lidar data collection was performed
with a Cessna 310 aircraft, utilizing a Leica ALS50-II MPiA sensor, collecting multiple return x, y, and z data as well as
intensity data. Lidar data was processed to achieve a bare ground surface (Classes 2 and 8). Lidar data is remotely sensed
high-resolution elevation data collected by an airborne collection platform. Using a combination of laser range
finding, GPS positioning and inertial measurement technologies, lidar instruments are able to make highly
detailed Digital Elevation Models (DEMs) of the earth's terrain, man-made structures, and vegetation.
The purpose of this project is to collect and deliver topographic elevation point data derived from multiple
return light detection and ranging (lidar) measurements for a 16-county area in South Carolina. The elevation data will
be used as base data for South Carolina's flood plain mapping program (as part of FEMA's Map Modernization
Program) and for additional geospatial map products in the future.
10611
The LiDAR Quality Assurance (QA) Report Fairfield County, South Carolina may be viewed at:
https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/503/supplemental/LiDAR_QAQC_Report_Fairfield.pdf
Theme
ISO 19115 Topic Category
elevation
Theme
Bare Earth
Theme
Intensity
Theme
Surface
Theme
Terrain
Office for Coastal Management
Charleston
SC
Data Set
Unknown
The information contained in the LAS point cloud data set are the following attributes; X, Y, Z to two significant digits;
Intensity as integer; Class as integer; Return number; Number of returns; Scan direction; scan angle rank; GPS time.
Lidar point cloud data tiled in LAS 1.1 format; ASPRS classification scheme,
class 12 - flight line overlap points, class 9 - points in water, class 8 - model-key points, class 2 - ground points,
and class 1 - all other.
Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners.
Data Steward
2009
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Distributor
2009
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Metadata Contact
2009
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Point of Contact
2009
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Ground Condition
-81.4319
-80.770691
34.58137
34.172798
Range
2008-01-15
2008-02-10
Yes
Unclassified
This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer
The data set is dynamically generated based on user-specified parameters.
;
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.
https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=503
Customized Download
Create custom data files by choosing data area, product type, map projection, file format, datum, etc.
https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/503/index.html
Bulk Download
Simple download of data files.
https://coast.noaa.gov
Online Resource
https://coast.noaa.gov/dataviewer
Online Resource
2016-05-23
Date that the source FGDC record was last modified.
2017-11-14
Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using 'fgdc_to_inport_xml.pl' script. Contact Tyler Christensen (NOS) for details.
2018-02-08
Partial upload of Positional Accuracy fields only.
2018-03-13
Partial upload to move data access links to Distribution Info.
The following methods are used to assure lidar accuracy:
1. Use of IMU and ground control network utilizing GPS techniques
2. Use of airborne GPS in conjunction with the acquisition of lidar
3. Measurement of quality control ground survey points within the finished product.
The boresight of the lidar was processed against the ground control for Fairfield County which consisted of
11 lidar ground survey points and 1 airborne GPS (ABGPS) base station at the operation airport. The horizontal datum
for the control was the North American Datum of 1983, 2007 adjustment (NAD83/2007). The vertical datum was
the North American Vertical Datum of 1988 (NAVD88). The Geoid 2003 model was used to transform the
ellipsoidal heights to GPS derived orthometric heights. ABGPS data was collected during the acquisition mission
for each flight line. During the data acquisition the Positional Dilution of Precision (PDOP) for the ABGPS
was monitored. The control points were measured by technicians using Terrascan and Fugro EarthData
proprietary software and applied to the boresight solution for the project lines.
The minimum expected horizontal accuracy was tested during the boresight process to meet or exceed the
National Standard for Spatial Data Accuracy (NSSDA). Horizontal accuracy is 1 meter RMSE or better.
108 high accuracy checkpoints were surveyed following FEMA Guidelines and Specifications for Flood Hazard Mapping
Partners Appendix A: Guidance for Aerial Mapping and Surveying which is based on the NSSDA. Compared with the 0.363m
specification for vertical accuracy at the 95% confidence level, equivalent to 2-foot contours, the dataset passes by
all methods of accuracy assessment (tested by Dewberry):
Tested 0.114 meter Fundamental Vertical Accuracy at 95 percent confidence level in open terrain using
RMSEz x 1.9600 (FEMA/NSSDA and NDEP/ASPRS methodologies);
Tested 0.147 meter Consolidated Vertical Accuracy at 95th percentile in all land cover categories combined
(NDEP/ASPRS methodology);
Tested 0.154 meter Supplemental Vertical Accuracy at 95th percentile in Vegetated terrain (NDEP/ASPRS methodology);
Tested 0.131 meter Supplemental Vertical Accuracy at 95th percentile in Urban terrain (NDEP/ASPRS methodology).
Cloud Cover: 0
The bare earth surface will contain voids where insufficient energy was reflected from the surface to generate a valid
return from the terrain. Voids in the bare earth surface tend to occur in heavily vegetated areas, water bodies, and
beneath buildings, motor vehicles, bridges etc. Fresh or wet asphalt, wet sand and certain types of vegetation can
also cause voids or anomalous elevations.
Compliance with the accuracy standard was ensured by the collection of GPS ground control during the acquisition
of aerial lidar and the establishment of a GPS base station operation airport.
The following checks were performed:
1. The ground control and airborne GPS data stream were validated through a fully analytical boresight adjustment.
2. The Lidar elevation data were checked against the project control.
3. Lidar elevation data was validated through an inspection of edge matching and visual inspection for quality (artifact removal).
Aerial Acquisition of Lidar Data for 16 counties in the State of South Carolina
2008-02-15
Range
2008-01-15
2008-02-10
The Fugro EarthData, Inc. acquisition team of Fugro Horizons, Inc. and North West Group collected ALS50-II
derived lidar over 16 counties in the State of South Carolina with a 1.4m, nominal post spacing using a
Cessna 310 aircraft. The collection for the entire project area was accomplished from January 15, 2008 through
February 10, 2008 (Flight dates were January 15, 16, 18, 20, 21, 25, 27, 28, 29, 30, 31 and February 2, 3, 4, 7, 8,
10). The collection was performed using a Leica ALS50-II MPiA lidar system, serial numbers ALS039 and ALS064,
including an inertial measuring unit (IMU) and a dual frequency GPS receiver. This project required 44 lifts of
flight lines to be collected. The lines were flown at an average of 6,000 feet above mean terrain using a
maximum pulse rate frequency of 112,000 pulses per second. The planned maximum baseline length was 50 miles.
| Type of Source Media: external hard drive
Fairfield County, SC - Digital Orthophotography
Discrete
2006-05-09
The State of South Carolina, Department of Natural Resources provided digital orthophotography covering the
project area in support of this project.
| Type of Source Media: external hard drive
South Carolina Lidar, Quality Control Surveys, 16 Counties
2008-01-31
Discrete
2008-01-21
ESP under contract to Fugro EarthData, Inc. successfully established ground control for Fairfield County, SC.
A total of 11 ground control points in Fairfield County, SC were acquired. GPS was used to establish the control
network. The horizontal datum was the North American Datum of 1983, 2007 adjustment (NAD83/2007).
The vertical datum was the North American Vertical Datum of 1988 (NAVD88).
| Type of Source Media: electronic mail system
1
1. Lidar, GPS, and IMU data was processed together using lidar processing software.
2. The lidar data set for each flight line was checked for project area coverage and lidar post spacing was checked
to ensure it meets project specifications.
3. The lidar collected at the calibration area and project area were used to correct the rotational, atmospheric, and
vertical elevation differences that are inherent to lidar data.
4. Intensity rasters were generated to verify that intensity was recorded for each lidar point.
5. Lidar data was transformed to the specified project coordinate system.
6. By utilizing the ground survey data collected at the calibration site and project area, the lidar data was
vertically biased to the ground.
7. Comparisons between the biased lidar data and ground survey data within the project area were evaluated and a
final RMSE value was generated to ensure the data meets project specifications.
8. Lidar data in overlap areas of project flight lines were trimmed and data from all swaths were merged into a single
data set.
9. The data set was trimmed to the digital project boundary including an additional buffer zone of 50 feet (buffer zone
assures adequate contour generation from the DEM).
10.The resulting data set is referred to as the raw lidar data.
2008-06-25T00:00:00
2
1. The raw lidar data was processed through a minimum block mean algorithm, and points were classified as either
bare earth or non-bare earth.
2. User developed "macros" that factor mean terrain angle and height from the ground were used to determine bare
earth point classification.
3. The next phase of the surfacing process was a 2D edit procedure that ensures the accuracy of the automated
feature classification.
4. Editors used a combination of imagery, intensity of the lidar reflection, profiles, and tin-editing software to assess
points.
5. The lidar data was filtered, as necessary, using a quadric error metric to remove redundant points. This
method leaves points where there is a change in the slope of surfaces (road ditches) and eliminates points from evenly
sloped terrain (flat field) where the points do not affect the surface.
6. The algorithms for filtering data were utilized within Fugro EarthData's proprietary software and commercial software
written by TerraSolid.
7. The flight line overlap points were merged back into filtered data set for delivery product.
8. The point cloud data were delivered tiled in LAS 1.1 format; class 12 - flight line overlap points, class 9 - points
in water, class 8 - model-key points, class 2 - ground
points, and class 1 - all other.
2008-12-18T00:00:00
3
Lidar intensity images were generated in TerraSolid software. The images are then brought up in Photoshop to
see if a curve is needed to modify the radiometrics and to ensure they match from group to group. Along with looking
for missing coverage and clipping to the boundary, the following steps are run in Photoshop:
1. Flip 0 values to 1
2. Change 3-band images to 1 band
3. Restore GeoTIFF headers. The intensity images were delivered in GeoTIFF format.
2008-12-16T00:00:00
4
Tiled lidar LAS datasets are imported into a single multipoint geodatabase featureclass. Only Ground and
Model-Keypoint are imported. An ArcGIS geodatabase terrain feature class is created using the terrain creation
dialogue provided through ArcCatalog. The multipoint featureclass is imported as mass point features in the
terrain. An overall tile boundary for the county is input as a soft clip feature for the terrain. The terrain pyramid level
resolutions and scales are automatically calculated based on the point coverage for the county.
2008-12-21T00:00:00
5
The NOAA Office for Coastal Management (OCM) received files in LAS format. The files contained
LiDAR intensity and elevation measurements. OCM performed the following processing on the data to make it available
within Digital Coast:
1. The data were converted from State Plane, SPCS Zone 3900 coordinates to geographic coordinates.
2. The data were converted from NAVD88 heights to ellipsoid heights using Geoid03.
3. The LAS header fields were sorted by latitude and updated.
2009-09-01T00:00:00
gov.noaa.nmfs.inport:49967
Anne Ball
2017-11-15T15:23:27
SysAdmin InPortAdmin
2022-08-09T17:11:38
2022-03-16
OCM Partners
OCMP
1002
Public
No
2022-03-16
1 Year
2023-03-16