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OCM Partners, 2024: 2018 USGS Lidar: North Slope, AK - QL2, https://www.fisheries.noaa.gov/inport/item/63177.

Item Identification

Title: 2018 USGS Lidar: North Slope, AK - QL2
Status: Completed
Publication Date: 2019-05-02
Abstract:

Product: Classified light detection and ranging (lidar) LAS 1.4 files formatted to 4,474 1500 ft x 1500 ft tiles.

In July 2018, Quantum Spatial (QSI) was contracted by the United States Geological Survey (USGS) to collect Light Detection and Ranging (LiDAR) data in the summer of 2018 for several areas of interest (AOIs), comprising the North Slope Borough Communities 3DEP LiDAR project in Alaska. Data were collected to aid USGS in assessing the topographic and geophysical properties of the study area, to support its mission to gather high quality 3D elevation data over the state of Alaska.

Due to inclement weather and the short acquisition timeframe in Alaska, QSI was able to collect LiDAR data in eight out of the eleven contracted AOIs in the 2018 acquisition season: Atqasuk, Barrow North, Barrow South, Barrow Village, Deadhorse, Kaktovic, Nuiqsut and Wainwright. Data collection for the remaining AOIs: Anaktuvuk Pass, Point Lay, and Point Hope was then completed in the summer of 2019.

Dataset Description: The North Slope Borough 3DEP LiDAR project called for the planning, acquisition, and processing of LiDAR data collected at an aggregate nominal pulse spacing (ANPS) of either 0.35 meters or 0.70 meters depending on area. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base LiDAR Specification, Version 1.3. The data was developed based on the NAD83(2011) horizontal datum and NAVD88 (GEOID12B) vertical datum. Data was projected in the appropriate Alaska State Plane Zone for its location.

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, hydroflattened DEMs, highest hit DSMs, intensity images, 2 foot contours, 3D hydro breaklines, and 3D building footprints.

Supplemental Information:

CONTRACTOR: Quantum Spatial, Inc.

Ground Control Points were acquired by Umiaq.

Quantum Spatial coordinated the data acquisition and performed all calibration, follow up processing, and creation of the final derived products.

The following are the USGS lidar fields in JSON:

{

"ldrinfo" : {

"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification v1.3",

"ldrsens" : "Leica ALS80",

"ldrmaxnr" : "15",

"ldrnps" : "0.5",

"ldrdens" : "4",

"ldranps" : "0.35",

"ldradens" : "8",

"ldrfltht" : "1750",

"ldrfltsp" : "115",

"ldrscana" : "30",

"ldrscanr" : "58.4",

"ldrpulsr" : "321.4",

"ldrpulsd" : "2.5",

"ldrpulsw" : "0.75",

"ldrwavel" : "1064",

"ldrmpia" : "2",

"ldrbmdiv" : "0.22",

"ldrswatw" : "938",

"ldrswato" : "60",

"ldrgeoid" : "National Geodetic Survey (NGS) Geoid12B"

},

"ldrinfo" : {

"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification v1.3",

"ldrsens" : "Leica ALS80",

"ldrmaxnr" : "15",

"ldrnps" : "1",

"ldrdens" : "1",

"ldranps" : "0.70",

"ldradens" : "2",

"ldrfltht" : "1750",

"ldrfltsp" : "140",

"ldrscana" : "38",

"ldrscanr" : "53.3",

"ldrpulsr" : "202",

"ldrpulsd" : "2.5",

"ldrpulsw" : "0.75",

"ldrwavel" : "1064",

"ldrmpia" : "1",

"ldrbmdiv" : "0.22",

"ldrswatw" : "1205",

"ldrswato" : "30",

"ldrgeoid" : "National Geodetic Survey (NGS) Geoid12B"

},

"ldraccur" : {

"ldrchacc" : "0.5",

"rawnva" : "0.042",

"rawnvan" : "45",

"clsnva" : "0.042",

"clsnvan" : "45",

"clsvva" : "0.154",

"clsvvan" : "24"

},

"lasinfo" : {

"lasver" : "1.4",

"lasprf" : "6",

"laswheld" : "Withheld (ignore) points were identified in these files using the standard LAS Withheld bit.",

"lasolap" : "Swath "overage" points were identified in these files 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 (0.5-2 meters)"

},

"lasclass" : {

"clascode" : "4",

"clasitem" : "Medium Vegetation (2-6 meters)"

},

"lasclass" : {

"clascode" : "5",

"clasitem" : "High Vegetation (6+ meters)"

},

"lasclass" : {

"clascode" : "6",

"clasitem" : "Buildings"

},

"lasclass" : {

"clascode" : "7",

"clasitem" : "Noise"

},

"lasclass" : {

"clascode" : "9",

"clasitem" : "Water"

},

"lasclass" : {

"clascode" : "17",

"clasitem" : "Bridge Decks"

},

"lasclass" : {

"clascode" : "20",

"clasitem" : "Ignored Ground"

},

"lasclass" : {

"clascode" : "21",

"clasitem" : "Snow"

}

}}

Keywords

Theme Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY > COASTAL BATHYMETRY
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION
ISO 19115 Topic Category
elevation

Spatial Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Location Keywords
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
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
Global Change Master Directory (GCMD) Location Keywords
VERTICAL LOCATION > SEA FLOOR
UNCONTROLLED
Global Change Master Directory (GCMD) Location Keywords Continent > North America > United States Of America > Alaska > Kaktovic
Global Change Master Directory (GCMD) Location Keywords Continent > North America > United States Of America > Alaska > North Slope
Global Change Master Directory (GCMD) Location Keywords Continent > North America > United States Of America > U.S. Coastline > Alaska

Instrument Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Instrument Keywords
LIDAR > Light Detection and Ranging

Platform Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Platform Keywords
Airplane > Airplane

Physical Location

Organization: Office for Coastal Management
City: Charleston
State/Province: SC

Data Set Information

Data Set Scope Code: Data Set
Data Set Type: Elevation
Maintenance Frequency: None Planned
Data Presentation Form: Model (digital)
Distribution Liability:

Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners

Data Set Credit: USGS, Quantum Spatial, Inc.

Support Roles

Data Steward

CC ID: 991988
Date Effective From: 2020
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

CC ID: 991987
Date Effective From: 2020
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

CC ID: 991989
Date Effective From: 2020
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

CC ID: 991990
Date Effective From: 2020
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

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 1145250
W° Bound: -166.84204
E° Bound: -143.606958
N° Bound: 71.31159
S° Bound: 68.091777

Extent Group 1 / Time Frame 1

CC ID: 1145249
Time Frame Type: Range
Start: 2018-07-14
End: 2019-08-18
Description:

Collection dates of lidar.

Spatial Information

Spatial Representation

Representations Used

Grid: No
Vector: Yes
Text / Table: No
TIN: No
Stereo Model: No
Video: No

Vector Representation 1

CC ID: 991999
Point Object Present?: Yes
Point Object Count: 2642856568

Access Information

Security Class: Unclassified
Data Access Procedure:

Data is available online for bulk or 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

CC ID: 991991
Start Date: 2020-10-29
End Date: Present
Download URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9198/details/9198
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2020 - Present)
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. Change to an orthometric vertical datum is one of the many options.

File Type (Deprecated): Zip
Compression: Zip

Distribution 2

CC ID: 991992
Start Date: 2020-10-29
End Date: Present
Download URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/9198/
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2020 - Present)
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. They will be in an orthometric datum.

File Type (Deprecated): LAZ
Distribution Format: LAS/LAZ - LASer
Compression: Zip

URLs

URL 1

CC ID: 991993
URL: https://coast.noaa.gov/dataviewer/
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 2

CC ID: 991994
URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/9198/supplemental/extent_AK_nslope_QL2_m9198.kmz
Name: Browse graphic
URL Type:
Browse Graphic
File Resource Format: KML
Description:

This graphic displays the footprint for this lidar data set.

URL 3

CC ID: 991995
URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/9198/supplemental/2019_North_Slope_Borough_Communities_3DEP_LiDAR_Technical_Data_Report.pdf
Name: Dataset report
URL Type:
Online Resource
File Resource Format: PDF
Description:

Link to data set report.

Data Quality

Vertical Positional Accuracy:

Absolute accuracy was assessed using Non-Vegetated Vertical Accuracy (NVA) reporting designed to meet guidelines presented in the FGDC National Standard for Spatial Data Accuracy. NVA compares known ground check point data that were withheld from the calibration and post-processing of the LiDAR point cloud to the triangulated surface generated by the unclassified LiDAR point cloud as well as the derived gridded bare earth DEM. NVA is a measure of the accuracy of LiDAR point data in open areas where the LiDAR system has a high probability of measuring the ground surface and is evaluated at the 95% confidence interval (1.96 * RMSE).

The mean and standard deviation (sigma ) of divergence of the ground surface model from quality assurance point coordinates are also considered during accuracy assessment. These statistics assume the error for x, y and z is normally distributed, and therefore the skew and kurtosis of distributions are also considered when evaluating error statistics. For the North Slope Borough Communities survey, 56 ground check points were withheld from the calibration and post processing of the LiDAR point cloud, with resulting non-vegetated vertical accuracy of 0.140 feet (0.043 meters) as compared to unclassified LAS, and 0.139 feet (0.042 meters) as compared to the bare earth DEM, with 95% confidence. NVA of unclassified LAS files RMSE = 0.072 ft (0.022 m).

Completeness Report:

These LAS data files include all data points collected. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. No void areas or missing data exist. The raw point cloud is of good quality and data passes Non-Vegetated Vertical Accuracy specifications.

Conceptual Consistency:

Data covers the entire area specified for this delivery 1 area.

Data Management

Have Resources for Management of these Data Been Identified?: Yes
Approximate Percentage of Budget for these Data Devoted to Data Management: Unknown
Do these Data Comply with the Data Access Directive?: Yes
Actual or Planned Long-Term Data Archive Location: NCEI-CO
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?:

Data is backed up to tape and to cloud storage.

Lineage

Sources

Lidar Data

CC ID: 1145244
Contact Role Type: Originator
Contact Type: Organization
Contact Name: Quantum Spatial

Process Steps

Process Step 1

CC ID: 1145245
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 geoid 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.

Process Date/Time: 2019-04-30 00:00:00

Process Step 2

CC ID: 1145246
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 final NVA for the project using ground control quality check points.

Process Date/Time: 2019-04-30 00:00:00

Process Step 3

CC ID: 1145247
Description:

The NOAA Office for Coastal Management (OCM) downloaded this data set from this USGS site:

ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/AK_NorthSlopeBorough_2018_B18/

All 14 subfolders, or blocks, were downloaded.

The total number of files downloaded and processed was 5,467.

OCM determined the following information regarding the USGS Quality Level (QL) and Alaska State Plane Zone projection for each block:

------------------------------------------------------------------------------------------------------

"NAD83(2011) / Alaska zone 4 (ftUS)"

B9 = QL1 B12 = QL2

B2 = QL1 B6 (2 AOIs) = QL2

------------------------------------------------------------------------------------------------------

"NAD83(2011) / Alaska zone 2 (ftUS)"

B1 = QL1 B5 = QL2

--------------------------------------------------------------------------------------------------------

"NAD83(2011) / Alaska zone 6 (ftUS)"

B3 = QL1 (2 AOIs) B7 (3 AOIs) = QL2

-----------------------------------------------------------------------------------------------------

"NAD83(2011) / Alaska zone 7 (ftUS)"

B4 = QL1 B8 = QL2

B10 = QL1 B13 = QL2

----------------------------------------------------------------------------------------------------

"NAD83(2011) / Alaska zone 8 (ftUS)"

B11 = Ql1 B14 = QL2

The data were in the above Alaska State Plane zones, (NAD83 2011), U.S. Feet coordinates and NAVD88 (Geoid12B) elevations in U.S Feet. The data were classified as: 1 - Unclassified, 2 - Ground, 3- Low Vegetation (0.5 - 2 meters), 4 - Medium Vegetation (2 - 6 meters), 5 - High Vegetation (6+ meters), 6 - Buildings, 7 - Noise, 9 - Water, 17 - Bridge Decks, 20 - Ignored Ground, 21 - Snow. OCM processed all classifications of points to the Digital Coast Data Access Viewer (DAV).

For this mission, only folders Blocks 5, 6, 7, 8, 12, 13 and 14 were processed, as these were determined to be the QL2 files.

OCM performed the following processing on the data for Digital Coast storage and provisioning purposes:

1. An internal OCM script was run to check the number of points by classification and by flight ID and the gps and intensity ranges.

2. Internal OCM scripts were run on the laz files to convert from orthometric (NAVD88) elevations to ellipsoid elevations using the Geoid12B model, to convert from Alaska State Plane (NAD83 2011), U.S. Feet coordinates to geographic coordinates, to assign the geokeys, to sort the data by gps time and zip the data to database and to http.

Process Contact: Office for Coastal Management (OCM)

Catalog Details

Catalog Item ID: 63177
GUID: gov.noaa.nmfs.inport:63177
Metadata Record Created By: Blake Waring
Metadata Record Created: 2020-11-02 16:48+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