2014 U.S. Geological Survey CMGP LiDAR: Post Sandy (Virginia)
Data Set (DS) | OCM Partners (OCMP)GUID: gov.noaa.nmfs.inport:50135 | Updated: August 9, 2022 | Published / External
Summary
Short Citation
OCM Partners, 2025: 2014 U.S. Geological Survey CMGP LiDAR: Post Sandy (Virginia), https://www.fisheries.noaa.gov/inport/item/50135.
Full Citation Examples
USGS Contract Number: G10PC00093, Task Order: G14PD00222
Digital Aerial Solutions LLC was tasked to collect and process 4607 sq. miles of Light Detection and Ranging (LiDAR) dataset in Virginia. The LiDAR Survey encompasses 4607 sq. miles of area in Eastern Virginia inclusive of the counties and cities of Spotsylvania, Caroline, Hanover, Henrico, Chesterfield, Dinwiddie, Sussex, Richmond City, Hopewell City, Colonial Heights City, Petersburg City, portions of Orange and Louisa, Amelia, Nottoway and Prince Edward. The LiDAR point cloud was flown at a nominal post spacing of 0.7 meters for un-obscured areas. The LiDAR data and derivative products produced are in compliance with the U.S. Geological Survey National Geospatial Program Guidelines and Base Specifications, Version 1.0. The final LAS point cloud classified as 1-Unclassified, 2-Ground, 7-Noise, 9-Water, 10-Ignored Ground due to breakline proximity, 17-overlap ground points and 18 - overlap unclassified points.
The GPS Survey was completed by ESP Associates for 3 block acquisition area, and 2 blocks acquisition area by Michale Baker Surveying totaling 4607 square miles through the project area.
Breaklines were delivered with the lidar dataset. These have not been reviewed by NOAA OCM, therefore are only available by request.
Distribution Information
-
Create custom data files by choosing data area, product type, map projection, file format, datum, etc.
-
Simple download of data files.
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be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions.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. These data depict the heights at the time of the survey and are only accurate for that time.
The data depicts the elevations at time of survey and are accurate only for that time. Exercise professional judgment in using this data.
Controlled Theme Keywords
elevation
Child Items
No Child Items for this record.
Contact Information
Point of Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov
Metadata Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov
Extents
-78.692546° W,
-76.953543° E,
38.39291° N,
36.70765° S
2014-03-24 - 2014-04-21
Item Identification
Title: | 2014 U.S. Geological Survey CMGP LiDAR: Post Sandy (Virginia) |
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Short Name: | va2014_usgs_cmgp_sandy_m4970_metadata |
Status: | Completed |
Publication Date: | 2016-01-09 |
Abstract: |
USGS Contract Number: G10PC00093, Task Order: G14PD00222 Digital Aerial Solutions LLC was tasked to collect and process 4607 sq. miles of Light Detection and Ranging (LiDAR) dataset in Virginia. The LiDAR Survey encompasses 4607 sq. miles of area in Eastern Virginia inclusive of the counties and cities of Spotsylvania, Caroline, Hanover, Henrico, Chesterfield, Dinwiddie, Sussex, Richmond City, Hopewell City, Colonial Heights City, Petersburg City, portions of Orange and Louisa, Amelia, Nottoway and Prince Edward. The LiDAR point cloud was flown at a nominal post spacing of 0.7 meters for un-obscured areas. The LiDAR data and derivative products produced are in compliance with the U.S. Geological Survey National Geospatial Program Guidelines and Base Specifications, Version 1.0. The final LAS point cloud classified as 1-Unclassified, 2-Ground, 7-Noise, 9-Water, 10-Ignored Ground due to breakline proximity, 17-overlap ground points and 18 - overlap unclassified points. The GPS Survey was completed by ESP Associates for 3 block acquisition area, and 2 blocks acquisition area by Michale Baker Surveying totaling 4607 square miles through the project area. Breaklines were delivered with the lidar dataset. These have not been reviewed by NOAA OCM, therefore are only available by request. |
Purpose: |
Evaluation of coastal storm damage impacts; aid in post-event reconstruction, and mitigation planning for future events, and collect LiDAR for counties heavily impacted by storm and flooding for which data is incomplete or inadequate to conduct proper analysis, as part of USGS Hurricane Sandy Response. |
Notes: |
10779 |
Supplemental Information: |
A footprint of this data set may be viewed in Google Earth at: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/4970/supplemental/va2014_usgs_cmgp_sandy_m4970.kmz A report for this the project may be viewed here: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/4970/supplemental/va2014_usgs_cmgp_sandy_m4970_lidarreport.pdf A survey report for this the project may be viewed here: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/4970/supplemental/va2014_usgs_cmgp_sandy_m4970_qualityreport.pdf |
Keywords
Theme Keywords
Thesaurus | Keyword |
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ISO 19115 Topic Category |
elevation
|
UNCONTROLLED | |
None | Bare earth |
Physical Location
Organization: | Office for Coastal Management |
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City: | Charleston |
State/Province: | SC |
Data Set Information
Data Set Scope Code: | Data Set |
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Maintenance Frequency: | As Needed |
Data Presentation Form: | las |
Entity Attribute Overview: |
LiDAR points in LAS format (ASPRS Classes 1,2,7,9,10,17,18) |
Entity Attribute Detail Citation: |
none |
Distribution Liability: |
Any conclusions drawn from the analysis of this information are not the responsibility of Digital Aerial Solutions LLC, USGS, NOAA, the Office for Coastal Management or its partners. |
Support Roles
Data Steward
Date Effective From: | 2016-01-09 |
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Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Distributor
Date Effective From: | 2016-01-09 |
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Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Metadata Contact
Date Effective From: | 2016-01-09 |
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Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Point of Contact
Date Effective From: | 2016-01-09 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Extents
Currentness Reference: | Ground Condition |
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Extent Group 1
Extent Group 1 / Geographic Area 1
W° Bound: | -78.692546 | |
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E° Bound: | -76.953543 | |
N° Bound: | 38.39291 | |
S° Bound: | 36.70765 |
Extent Group 1 / Time Frame 1
Time Frame Type: | Range |
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Start: | 2014-03-24 |
End: | 2014-04-21 |
Spatial Information
Spatial Representation
Representations Used
Vector: | Yes |
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Access Information
Security Class: | Unclassified |
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Data Access Procedure: |
This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=4970; |
Data Access Constraints: |
None |
Data Use Constraints: |
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. These data depict the heights at the time of the survey and are only accurate for that time. The data depicts the elevations at time of survey and are accurate only for that time. Exercise professional judgment in using this data. |
Distribution Information
Distribution 1
Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=4970 |
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Distributor: | |
File Name: | Customized Download |
Description: |
Create custom data files by choosing data area, product type, map projection, file format, datum, etc. |
Distribution 2
Download URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/4970/index.html |
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Distributor: | |
File Name: | Bulk Download |
Description: |
Simple download of data files. |
URLs
URL 1
URL: | https://coast.noaa.gov/dataviewer |
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URL Type: |
Online Resource
|
URL 2
URL: | https://coast.noaa.gov |
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URL Type: |
Online Resource
|
URL 3
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/4970/supplemental/va2014_usgs_cmgp_sandy_m4970.kmz |
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Name: | Browse Graphic |
URL Type: |
Browse Graphic
|
File Resource Format: | kmz |
Description: |
This graphic shows the lidar coverage for the 2014 lidar acquisition for mainland Virginia. A separate project was contracted and tasked for the Delmarva peninsula portion of Virginia. |
Activity Log
Activity Log 1
Activity Date/Time: | 2016-07-11 |
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Description: |
Date that the source FGDC record was last modified. |
Activity Log 2
Activity Date/Time: | 2017-11-14 |
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Description: |
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. |
Activity Log 3
Activity Date/Time: | 2018-02-08 |
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Description: |
Partial upload of Positional Accuracy fields only. |
Activity Log 4
Activity Date/Time: | 2018-03-13 |
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Description: |
Partial upload to move data access links to Distribution Info. |
Data Quality
Accuracy: |
Newly processed vectors were entered into the StarNet Least Squares adjustment program holding the NAD83-2011(epoch 2010) CORS and existing monumented NGS published coordinates, along with the inclusion of the Geoid12A model. A horizontal accuracy of 2nd Order Class I (1:50,000) and the vertical NAVD88 accuracy at 3rd Order (+/- 0.06') were achieved.+ |
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Horizontal Positional Accuracy: |
There is not a systematic method of testing when testing horizontal accuracy in LiDAR. However this is tested during calibration of the sensor and is rechecked during the comparing of parallel and perpendicular flight lines. Additionally the horizontal accuracy is checked by collecting building corners during the survey. Lines are then digitized representing the building outline and the differences are measure from each individual survey point to the corner of the building outline. Stats are calculated to ensure horizontal tolerances are met. These measurements resulted in an RMSE of .42 meters and equals a .73 meter horizontal accuracy at the 95 % confidence level. Accuracy defined by NSSDA at the 95 % confidence level would be multiplier by 1.7308 times the RMSE. The accuracy assessment was performed using the NSSDA standard method to compute the root mean square error (RMSE) based on a comparison of ground control points (GCP) and filtered LiDAR data points. Filtered LiDAR data has had vegetation and cultural features removed and by analysis represent bare earth elevations. Testing was performed prior to gridding of the filtered LiDAR data points and construction of the 32-bit ERDAS Imagine format bare earth tiles. The RMSEz figure was used to compute the vertical National Standard for Spatial Data Accuracy (NSSDA). A spatial proximity analysis was used to select edited LiDAR data points contiguous to the relevant GCPs. A search radius decision rule is applied with consideration of terrain complexity, cumulative error and adequate sample size. |
Vertical Positional Accuracy: |
(7.5 cm) 0.2806 ft RMSE; Quantitative Value: 0.147 meters, Test that produced the value: Tested 14.7 cm (0.55 ft.) fundamental vertical accuracy (FVA) at the 95% confidence level in open terrain, based on RMSEz x 1.9600. Tested against the DEM.; Quantitative Value: 0.202 meters, Test that produced the value: Tested 20.2 cm supplemental vertical accuracy (SVA) at the 95th percentile in Tallweed categories. Tested against the DEM.; Quantitative Value: 0.205 meters, Test that produced the value: Tested 20.5 cm supplemental vertical accuracy (SVA) at the 95th percentile in Brush Land catagories. Tested against the DEM.; Quantitative Value: 0.231 meters, Test that produced the value: Tested 23.1 cm supplemental vertical accuracy (SVA) at the 95th percentile in Forested catagories. Tested against the DEM.; Quantitative Value: 0.166 meters, Test that produced the value: Tested 16.6 cm supplemental vertical accuracy (SVA) at the 95th percentile in urban catagories. Tested against the DEM.; Quantitative Value: 0.187 meters, Test that produced the value: Tested 18.7 cm consolidated vertical accuracy (CVA) at the 95th percentile in all categories of data. Tested against the DEM. |
Completeness Report: |
GPS points were taken for five separate classes on flat or uniformly sloping terrain at least five meters away from any breakline. Output results are in NAD83-2011(epoch 2010) and UTM Zone 18, in meters, and VA State Plane North, in feet. There were a total 250 points in this Geodetic network. There are 18 existing and CORS marks utilized to control this network. There are 104 Control Points (CP), 29 Bear Earth, 25 Tall Weeds, 26 Brush areas, 26 Canopy (forest), , and 22 Urban locations. The vegetation height ranges were 0 - 0.5ft, 0.5 - 5ft, 5 - 6.5ft, > 6.5ft, 0 ft, respectively. |
Conceptual Consistency: |
Digital Aerial Solutions LLC was tasked to collect and process 4607 sq. miles of Light Detection and Ranging (LiDAR) dataset in Virginia. The LiDAR Survey encompasses 4607 sq. miles of area in Eastern Virginia inclusive of the counties and cities of Spotsylvania, Caroline, Hanover, Henrico, Chesterfield, Dinwiddie, Sussex, Richmond City, Hopewell City, Colonial Heights City, Petersburg City, portions of Orange and Louisa, Amelia, Nottoway and Prince Edward. The LiDAR point cloud was flown at a nominal post spacing of 0.7 meters for un-obscured areas. The LiDAR data and derivative products produced are in compliance with the U.S. Geological Survey National Geospatial Program Guidelines and Base Specifications, Version 1.0. The final LAS point cloud classified as 1-Unclassified, 2-Ground, 7-Noise, 9-Water, 10-Ignored Ground due to breakline proximity, 17-overlap ground points and 18 - overlap unclassified points. The GPS Survey was completed by ESP Associates for 3 block acquisition area, and 2 blocks acquisition area by Michale Baker Surveying totaling 4607 square miles through the project area. |
Lineage
Process Steps
Process Step 1
Description: |
The primary collection of LiDAR data was done by two Cessna 421 aircrafts. There were three LiDAR sensors used to acquire this mission; ALS60, ALS70 and an Optech Pegasus system. 35 flight missions were required to collect the entire area of the project area. The ABGPS, inertial measurement unit (IMU), and raw scans are collected during the LiDAR aerial survey. The ABGPS monitors the xyz position of the sensor and the IMU monitors the orientation. During the aerial survey, laser pulses reflected from features on the ground surface are detected by the receiver optics and collected by the data logger. GPS locations are based on data collected by receivers on the aircraft and base stations on the ground. The ground base stations are placed no more than 40 km radius from the flight survey area. |
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Process Date/Time: | 2014-04-02 00:00:00 |
Process Step 2
Description: |
The ABGPS, IMU, and raw scans are integrated using proprietary software developed by Leica and delivered with the Leica System. The resultant file is in a LAS binary file format. The LAS version 1.2 file format 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 number, intensity value, xyz, etc.). The resultant points are produced in UTM18/ NAD83 coordinate system, with units in Meters and Vertical datum referenced to the NAVD88 datum. The LiDAR mass points were processed in American Society for Photogrammetry and Remote Sensing LAS 1.2 format. The header file for each dataset is complete as defined by the LAS 1.2 specification. The datasets were divided into 1500 Meters by 1500 Meters tiling scheme, based on United States National Grid Index. The tiles are contiguous, do not overlap, and are suitable for seamless topographic data mosaics that include no "no data" areas. |
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Process Date/Time: | 2014-04-10 00:00:00 |
Process Step 3
Description: |
The unedited data are classified to facilitate the application of the appropriate feature extraction filters. Digital Aerial Solutions used Terrasolids Terrascan and Terramodel softwares to classify and edit the LAS data and a combination of proprietary filters are applied as appropriate for the production of bare earth digital elevation models (DEMs). 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. DAS classified the LAS data as follows: Class 1 = Unclassified. This class includes vegetation, buildings, noise etc. Class 2 = Ground Class 7 = Noise Class 9 = Water Class 10 = Ignored Ground Class 17 = overlap ground Class 18 = overlap unclassified |
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Process Date/Time: | 2014-04-25 00:00:00 |
Process Step 4
Description: |
Filtered and edited data are subjected to rigorous QA/QC, A series of quantitative and visual procedures are employed to validate the accuracy and consistency of the filtered and edited data. Ground control is established by DAS and GPS-derived ground control points (GCPs) in various areas of dominant and prescribed land cover. These points are coded according to land cover, surface material, and ground control suitability. A suitable number of points are selected for calculation of a statistically significant accuracy assessment, as per the requirements of the National Standard for Spatial Data Accuracy. A spatial proximity analysis is used to select edited LiDAR data points within a specified distance of the relevant GCPs. A search radius decision rule is applied with consideration of terrain complexity, cumulative error, and adequate sample size. Accuracy validation and evaluation is accomplished using proprietary software to apply relevant statistical routines for calculation of Root Mean Square Error (RMSE) and the National Standard for Spatial Data Accuracy (NSSDA), according to Federal Geographic Data Committee (FGDC) specifications. |
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Process Date/Time: | 2014-05-22 00:00:00 |
Process Step 5
Description: |
The Bare Earth DEM was extracted from the raw LIDAR products and attributed with the bare earth elevation for each cell of the DEM. Bare Earth DEMs do not include buildings, vegetation, bridges or overpass structures in the bare earth model. Where abutments were clearly delineated, this transition occurred at the junction of the bridge and abutment. Where this junction was not clear, the extractor used their best estimate to delineate the separation of ground from elevated bridge surface. In the case of bridges over water bodies, if the abutment was not visible, the junction was biased to the prevailing stream bank so as not to impede the flow of water in a hydrographic model. Bare earth surface includes the top of water bodies not underwater terrain, if visible. |
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Process Date/Time: | 2014-05-25 00:00:00 |
Process Step 6
Description: |
The NOAA Office for Coastal Management (OCM) received the topographic files in classified LAZ format from USGS' ftp site. The data were received in UTM Zone 18N NAD83 coordinates (meters) and vertically referenced to NAVD88 using the Geoid12a model in meters. OCM performed the following processing for data storage and Digital Coast provisioning purposes: 1. LAS files were compressed to LAZ format with LASTools. 2. LAS files were removed of any duplicated points and extraneous points were reclassified to noise. 3. The LAS files were transformed to geographic (decimal degrees), ellipsoidal coordinates (meters) referenced to the Geoid12a model. |
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Process Date/Time: | 2016-05-01 00:00:00 |
Catalog Details
Catalog Item ID: | 50135 |
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GUID: | gov.noaa.nmfs.inport:50135 |
Metadata Record Created By: | Anne Ball |
Metadata Record Created: | 2017-11-15 15:24+0000 |
Metadata Record Last Modified By: | SysAdmin InPortAdmin |
Metadata Record Last Modified: | 2022-08-09 17:11+0000 |
Metadata Record Published: | 2022-03-16 |
Owner Org: | OCMP |
Metadata Publication Status: | Published Externally |
Do Not Publish?: | N |
Metadata Last Review Date: | 2022-03-16 |
Metadata Review Frequency: | 1 Year |
Metadata Next Review Date: | 2023-03-16 |