2017 USGS 3DEP Lidar: Fairbanks, AK (QL1 & QL2)
Data Set (DS) | OCM Partners (OCMP)GUID: gov.noaa.nmfs.inport:55358 | Updated: October 17, 2023 | Published / External
Item Identification
Title: | 2017 USGS 3DEP Lidar: Fairbanks, AK (QL1 & QL2) |
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Short Name: | ak2017_fairbanks_m8663_metadata.xml |
Status: | Completed |
Publication Date: | 2018-04-18 |
Abstract: |
In May 2017, Quantum Spatial (QSI) was contracted by the United States Geological Survey (USGS) to collect QL1 and QL2 Light Detection and Ranging (LiDAR) data over approximately 1.8 million acres of land for the Fairbanks 3DEP mapping site in Alaska (Task Order G17PD00606). Data were collected to aid USGS in assessing the topographic and geophysical properties of the study area to support the 3DEP mapping initiative. Geographic Extent: The QL1 area encompasses 248,555 acres and the QL2 area encompasses 1,186,822 acres. Dataset Description: RAW flight line swaths were processed to create 6,268 classified LAS 1.4 files delineated in 3000 x 3000 ft tiles tiles. Each LAS file contains LiDAR point information, which has been calibrated, controlled, and classified. LAS files have been edited to the extent of the buffered boundary. Additional derived products include intensity images, hydro-flattened DEMs, highest hit surface models, 2ft contours, and 3D breaklines of rivers and lakes within the study area. Ground Conditions: Data was acquired during conditions with an absence of snow, high water, ground fog and/or clouds below the flight altitudes. The NOAA Office for Coastal Management (OCM) downloaded 1203 laz files from ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/USGS_LPC_AK_FairbanksNSB_QL1_2017_LAS_2018/ and 6268 laz files from ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/USGS_LPC_AK_FairbanksNSB_QL2_2017_LAS_2018 and processed the data to the Data Access Viewer (DAV) and https. Hydro and bridge breaklines are also available. These data are available for download at the link provided in the URL section of this metadata record. Please note that these products have not been reviewed by the NOAA Office for Coastal Management (OCM) and any conclusions drawn from the analysis of this information are not the responsibility of NOAA or OCM. |
Purpose: |
The purpose of the lidar data was to produce a high accuracy 3D dataset that meets all necessary standards laid out by the 3DEP initiative. The raw lidar point cloud data were used to create classified lidar LAS files, intensity images, hydro-flattened DEMs, highest hit surface models, 2ft contours, and 3D breaklines of rivers and lakes within the study area. |
Supplemental Information: |
CONTRACTOR: Quantum Spatial, Inc. Ground Control Points were acquired DOWL Engineering. All Lidar data acquisition, calibration, and follow-on processing were completed by the prime contractor.
The following are the USGS lidar fields in JSON: {
"ldrinfo" : {
"ldrspec" : "National Geospatial Program Lidar Base Specification Version 1.2", "ldrsens" : "ALS-70", "ldrmaxnr" : "15", "ldrnps" : ".71", "ldrdens" : "2", "ldranps" : "0.71", "ldradens" : "2", "ldrfltht" : "1600", "ldrfltsp" : "145", "ldrscana" : "30", "ldrscanr" : "50.2", "ldrpulsr" : "175", "ldrpulsd" : "9", "ldrpulsw" : "2.698", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "22", "ldrswatw" : "857", "ldrswato" : "28", "ldrgeoid" : "National Geodetic Survey (NGS) Geoid12B" }, "ldraccur" : {
"ldrchacc" : "0.5", "rawnva" : "0.376 ft", "rawnvan" : "321" }, "lasinfo" : {
"lasver" : "1.4", "lasprf" : "6", "laswheld" : "Withheld points are identified using the standard LAS witheld bit.", "lasolap" : "Swath overage points are identified using the standard LAS overlap bit.", "lasintr" : "16", "lasclass" : {
"clascode" : "1", "clasitem" : "Processed, but Unclassified" }, "lasclass" : {
"clascode" : "2", "clasitem" : "Bare earth ground" }, "lasclass" : {
"clascode" : "3", "clasitem" : "Low Vegetation (0.5m - 2m)" }, "lasclass" : {
"clascode" : "4", "clasitem" : "Medium Vegetation (2m - 6m)" }, "lasclass" : {
"clascode" : "5", "clasitem" : "High Vegetation (6m+)" }, "lasclass" : {
"clascode" : "6", "clasitem" : "Buildings (automated classification only)" }, "lasclass" : {
"clascode" : "7", "clasitem" : "Low Noise" }, "lasclass" : {
"clascode" : "9", "clasitem" : "Water" }, "lasclass" : {
"clascode" : "10", "clasitem" : "Ignored Ground Near Breakline" }, "lasclass" : {
"clascode" : "17", "clasitem" : "Bridge Decks" } }} |
Keywords
Theme Keywords
Thesaurus | Keyword |
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Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
|
ISO 19115 Topic Category |
elevation
|
UNCONTROLLED | |
None | erosion |
Spatial Keywords
Thesaurus | Keyword |
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Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALASKA
|
Global Change Master Directory (GCMD) Location Keywords |
VERTICAL LOCATION > LAND SURFACE
|
Instrument Keywords
Thesaurus | Keyword |
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Global Change Master Directory (GCMD) Instrument Keywords |
LIDAR > Light Detection and Ranging
|
Platform Keywords
Thesaurus | Keyword |
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Global Change Master Directory (GCMD) Platform Keywords |
Airplane > Airplane
|
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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Data Set Type: | Elevation |
Maintenance Frequency: | Unknown |
Data Presentation Form: | Point Cloud (Digital) |
Distribution Liability: |
Any conclusions drawn from the analysis of this information are not the responsibility of Quantum Spatial, Inc, USGS, NOAA, the Office for Coastal Management or its partners. |
Data Set Credit: | Quantum Spatial, Inc. coordinated the LiDAR acquisition and processed the data., Quantum Spatial, Inc. |
Support Roles
Data Steward
Date Effective From: | 2018 |
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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: | 2018 |
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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: | 2018 |
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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: | 2018 |
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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 |
Extents
Currentness Reference: | Ground Condition |
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Extent Group 1
Extent Group 1 / Geographic Area 1
W° Bound: | -148.712735 | |
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E° Bound: | -145.410639 | |
N° Bound: | 65.274619 | |
S° Bound: | 64.22307 |
Extent Group 1 / Time Frame 1
Time Frame Type: | Range |
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Start: | 2017-05-28 |
End: | 2017-09-03 |
Description: |
Collection period for the QL2 area. |
Extent Group 1 / Time Frame 2
Time Frame Type: | Range |
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Start: | 2017-06-13 |
End: | 2017-07-01 |
Description: |
Collection period for the QL1 area. |
Access Information
Security Class: | Unclassified |
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Data Access Procedure: |
Data is available online for bulk and custom downloads. |
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. |
Distribution Information
Distribution 1
Start Date: | 2018 |
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End Date: | Present |
Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8663 |
Distributor: | |
File Name: | Customized Download |
Description: |
Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base. |
Compression: | Zip |
Distribution 2
Start Date: | 2018 |
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End Date: | Present |
Download URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/8663/index.html |
Distributor: | |
File Name: | Bulk Download |
Description: |
Bulk download of data files in LAZ format, geographic coordinates, orthometric heights. Note that the vertical datum (hence elevations) of the files here are different than described in this document. |
File Type (Deprecated): | LAZ |
Distribution Format: | LAS/LAZ - LASer |
Compression: | Zip |
URLs
URL 1
URL: | https://coast.noaa.gov/ |
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Name: | NOAA's Office for Coastal Management (OCM) website |
URL Type: |
Online Resource
|
File Resource Format: | HTML |
Description: |
Information on the NOAA Office for Coastal Management (OCM) |
URL 2
URL: | https://coast.noaa.gov/dataviewer/ |
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Name: | NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV) |
URL Type: |
Online Resource
|
File Resource Format: | HTML |
Description: |
The Data Access Viewer (DAV) allows a user to search for and download elevation, imagery, and land cover data for the coastal U.S. and its territories. The data, hosted by the NOAA Office for Coastal Management, can be customized and requested for free download through a checkout interface. An email provides a link to the customized data, while the original data set is available through a link within the viewer. |
URL 3
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/8663/supplemental/ak2017_fairbanks_m8663.kmz |
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Name: | Browse graphic |
URL Type: |
Browse Graphic
|
File Resource Format: | KML |
Description: |
This graphic displays the footprint for this lidar data set. |
URL 4
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/8663/supplemental/Fairbanks_3DEP_LiDAR_Technical_Data_Report.pdf |
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Name: | Dataset report |
URL Type: |
Online Resource
|
File Resource Format: | |
Description: |
Link to data set report. |
URL 5
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/8663/breaklines/ |
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URL Type: |
Online Resource
|
Description: |
Link to the data set breaklines. |
Technical Environment
Description: |
LASTools, TerraPOS, Cloudpro 1.2.4, Microstation Version 8i, TerraScan Version 17, TerraModeler Version 17, ESRI ArcGIS 10.3, Windows 7 Operating System |
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Data Quality
Vertical Positional Accuracy: |
The specifications require that raw Non-vegetated Vertical Accuracy (NVA) be computed from the both the raw lidar point cloud swath files and the derived DEMs. Additionally, Vegetated Vertical Accuracy (VVA) is also to be computed from the derived DEMS. The NVA check points were collected by DOWL Engineering and distributed throughout the project as feasible. These check points were not used in the calibration or post processing of the lidar point cloud data. The VVA was collected by DOWL Engineering and tested with independent check points located in vegetated terrain, also witheld from the calibration and post processing of the lidar point cloud data and distributed throughout the project area as feasible. Specifications for this project require that the NVA be 19.6 cm (Swath, DEM) meters or better AccuracyZ at 95% confidence level and that the VVA be 29.4 cm (DEM) or better AccuracyZ at the 95th percentile. The following accuracy assessment reflects the combined accuracy results of QL1 and QL2 data. 0.115 m (0.376 ft) AccuracyZ at the 95 percent Confidence Interval for RAW LAS NVA. DEM NVA: 0.094 m (0.309 ft) AccuracyZ at the 95 percent Confidence Interval. DEM VVA: 0.209 m (0.687 ft) AccuracyZ at the 95th percentile. NVA was tested using 321 surveyed check points. Elevations interpolated from the unclassified lidar surface were compared to the elevation values of the surveyed NVA check points. The RMSE was computed to be 0.058 m (0.192 ft) resulting in an AccuracyZ at the 95% confidence level of 0.115 m (0.376 ft). The NVA check points were also compared to the elevations of the derived bare earth DEMs. The RMSE was computed to be 0.048 m (0.158 ft) resulting in an AccuracyZ of 0.094 m (0.309 ft) at the 95% confidence level. NVA AccuracyZ has been tested and meets the required 19.6 cm at 95% confidence level using (RMSEz * 1.9600) for both the raw lidar point cloud and derived DEMs, as defined by the National Standards for Spatial Data Accuracy (NSSDA) and herein reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines. Elevations of the 219 VVA check points were compared to the elevations of the derived bare earth DEMs. The RMSE was computed to be 0.113 m (0.371 ft) and resulted in an AccuracyZ of 0.209 m (0.687 ft) at the 95th percentile. AccuracyZ has been tested on the derived bare earth DEMs and meets the required 29.4 cm (DEM) VVA using the 95th percentile of the absolute value of all vertical errors in all combined vegetation classes as defined by the National Standards for Spatial Data Accuracy (NSSDA); and herein reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines. |
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Completeness Report: |
LAS files include all data points collected. No points have been removed or excluded. Shaded relief images have been visually inspected for data errors such as pits, border artifacts, and shifting. LiDAR flight lines have been examined to ensure consistent elevation values across overlapping flight lines. The raw point cloud is of good quality and data passes Vertical Accuracy specifications. |
Conceptual Consistency: |
Classified LAS files were tested by QSI for both vertical and horizontal accuracy. All data is seamless from one tile to the next, no gaps or no data areas. |
Lineage
Sources
Base Station Control
Contact Role Type: | Originator |
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Contact Type: | Organization |
Contact Name: | Quantum Spatial |
Publish Date: | 2018-04-18 |
Extent Type: | Discrete |
Extent Start Date/Time: | 2018-04-18 |
Source Contribution: |
This data source was used (along with the airborne GPS/IMU data) to georeference the LiDAR point cloud data. |
Ground Control Quality Check Points
Contact Role Type: | Originator |
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Contact Type: | Organization |
Contact Name: | Quantum Spatial |
Publish Date: | 2018-04-18 |
Extent Type: | Discrete |
Extent Start Date/Time: | 2018-04-18 |
Source Contribution: |
This data source was used to assess the accuracy of LiDAR point cloud data. |
LiDAR RAW Data
Contact Role Type: | Originator |
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Contact Type: | Organization |
Contact Name: | Quantum Spatial |
Publish Date: | 2018-04-18 |
Extent Type: | Range |
Extent Start Date/Time: | 2017-05-28 |
Extent End Date/Time: | 2017-09-03 |
Source Contribution: |
This data source was used to populate the LiDAR point cloud data. |
Smooth Best Estimate Trajectories
Contact Role Type: | Originator |
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Contact Type: | Organization |
Contact Name: | Quantum Spatial |
Publish Date: | 2018-04-18 |
Extent Type: | Discrete |
Extent Start Date/Time: | 2018-04-18 |
Source Contribution: |
This data source was used (along with base station control data) to georeference the LiDAR point cloud data. |
Supplemental Ground Control Points
Contact Role Type: | Originator |
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Contact Type: | Organization |
Contact Name: | Quantum Spatial |
Publish Date: | 2018-04-18 |
Extent Type: | Discrete |
Extent Start Date/Time: | 2018-04-18 |
Source Contribution: |
This data source was used to refine airborne GPS positional accuracy during the calibration process. |
Process Steps
Process Step 1
Description: |
LiDAR Pre-Processing: 1. Review flight lines and data to ensure complete coverage of the study area and positional accuracy of the laser points. 2. Resolve kinematic corrections for aircraft position data using kinematic aircraft GPS and static ground GPS data. 3. Develop a smoothed best estimate of trajectory (SBET) file that blends post-processed aircraft position with sensor head position and attitude recorded throughout the survey. 4. Calculate laser point position by associating SBET position to each laser point return time, scan angle, intensity, etc. Create raw laser point cloud data for the entire survey in *.las format. Convert data to orthometric elevations by applying a geoid12b correction. 5. Import raw laser points into manageable blocks (less than 500 MB) to perform manual relative accuracy calibration and filter erroneous points. Classify ground points for individual flight lines. 6. Using ground classified points per each flight line, test the relative accuracy. Perform automated line-to-line calibrations for system attitude parameters (pitch, roll, heading), mirror flex (scale) and GPS/IMU drift. Calculate calibrations on ground classified points from paired flight lines and apply results to all points in a flight line. Use every flight line for relative accuracy calibration. 7. Adjust the point cloud by comparing ground classified points to supplemental ground control points. |
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Process Date/Time: | 2018-04-16 00:00:00 |
Process Step 2
Description: |
LiDAR Post-Processing: 1. Classify data to ground and other client designated classifications using proprietary classification algorithms. 2. Manually QC data classification 3. After completion of classification and final QC approval, calculate NVA and VVA, and density information for the project using ground control quality check points. |
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Process Date/Time: | 2018-04-16 00:00:00 |
Process Step 3
Description: |
The NOAA Office for Coastal Management (OCM) downloaded 1203 laz files from ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/USGS_LPC_AK_FairbanksNSB_QL1_2017_LAS_2018/ and 6268 laz files from ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/USGS_LPC_AK_FairbanksNSB_QL2_2017_LAS_2018. The data were in Alaska State Plane, Zone 3 NAD83 2011, US survey feet, coordinates and NAVD88 (Geoid12B) elevations in feet. The data were classified as: 1 - Unclassified, 2 - Ground, 3 - Low vegetation (0.5 - 2 m), 4 - Medium vegetation (2 - 6 m), 5 - High vegetation (greater than 6 m), 6 - Buildings, 7 - Low Noise, 9 - Water, 10 - Ignored Ground, 17 - Bridge Decks. OCM processed all classifications of points to the Digital Coast Data Access Viewer (DAV). Classes available on the DAV are: 1, 2, 3, 4, 5, 6, 7, 9, 10, 17. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. The LAStools software script lasinfo was run on the laz files to check for errors. 2. An internal OCM script was run to check the number of points by classification and by flight ID, and the gps and intensity ranges. 3. Internal OCM scripts were run on the laz files to convert from orthometric (NAVD88) elevations to ellipsoid elevations using the Geoid 12B model, to convert from elevations in feet to meters, to convert from Alaska State Plane, Zone 3 coordinates in US survey feet to geographic coordinates, to assign the geokeys, to sort the data by gps time and zip the data to database and to http. |
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Process Date/Time: | 2019-01-24 00:00:00 |
Process Contact: | Office for Coastal Management (OCM) |
Catalog Details
Catalog Item ID: | 55358 |
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GUID: | gov.noaa.nmfs.inport:55358 |
Metadata Record Created By: | Rebecca Mataosky |
Metadata Record Created: | 2019-01-17 11:09+0000 |
Metadata Record Last Modified By: | SysAdmin InPortAdmin |
Metadata Record Last Modified: | 2023-10-17 16:12+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 |