2024 NOAA Lidar: AK Coastal Communities (Eek, Goodnews Bay, Nelson Lagoon, Quinhagak, Togiak)
Data Set (DS) | Office for Coastal Management (OCM)GUID: gov.noaa.nmfs.inport:77595 | Updated: September 3, 2025 | Published / External
-
View As
- Full List View
- EXPORTS
- InPort XML
- ISO 19115
- WAF Files
- View in Hierarchy
Summary
Short Citation
Office for Coastal Management, 2026: 2024 NOAA Lidar: AK Coastal Communities (Eek, Goodnews Bay, Nelson Lagoon, Quinhagak, Togiak), https://www.fisheries.noaa.gov/inport/item/77595.
Full Citation Examples
Original Product: Classified LAZ 1.4 files, formatted to 825 individual 750m x 750m tiles covering the NOAA AK Coastal Communities 2023 project area.
Original Dataset Geographic Extent: This dataset and derived products encompass five areas covering approximately 92,475 acres of Southwest Alaska.
Original Dataset Description: The NOAA AK Communities 2023 Lidar project called for the planning, acquisition, and processing of lidar data collected to Quality Level 1 (QL1) standards. Project specifications are based on the U.S. Geological Survey National Geospatial Program Lidar Base Specification Version 2023, Revision A. The data was developed based on the NAD83 2011 horizontal datum and the NAVD88 Geoid 12b vertical datum. Data was projected in UTM Zone 4N, Meters. Lidar data was delivered as calibrated and classified LAZ 1.4 files. Non-Vegetated Vertical Accuracy (NVA) was assessed using 101 check points located on bare earth in clear, unobstructed areas. Vegetated Vertical Accuracy (VVA) was assessed using 26 check points in Tall Grass, Forest, and Shrub landcover types. Single swath nominal pulse spacing (NPS) was designed to be 0.35 at nadir. Aggregate Nominal Pulse Spacing (ANPS) was calculated to be 0.269 with the Riegl VQ-780ii-S and 0.298 with the Riegl 1560iiS using all valid first return points. Derived products include: Intensity Imagery, Hydro-flattened Bare Earth Digital Elevation Models (DEMs), Maximum Surface Height Rasters (MSHRs), and 3D waters edge breaklines.
Ground Condition: Ground conditions were free of snow and acquisition occurred free of smoke, fog and cloud cover.
The purpose of the lidar data was to produce a high accuracy 3D dataset that meets all necessary standards laid out by the 3D Elevation Program and the NOAA AK Communities 2023 contract. The lidar point cloud data were used to create classified lidar LAZ files, intensity images, hydro-flattened DEMs, MSHRs, and 3D breaklines of rivers and lakes within the study area.
Data Access & Downloads
-
Format: Not Applicable
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.
-
LAS/LAZ - LASer
Bulk download of data files in LAZ format, UTM Zone 4N NAD83(2011) meters coordinates and elevations in NAVD88(GEOID12B) meters.
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.
Controlled Theme Keywords
COASTAL ELEVATION, elevation, TERRAIN ELEVATION
URLs
-
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.
-
Entwine Point Tile (EPT) is a simple and flexible octree-based storage format for point cloud data. The data is organized in such a way that the data can be reasonably streamed over the internet, pulling only the points you need. EPT files can be queried to return a subset of the points that give you a representation of the area. As you zoom further in, you are requesting higher and higher densities. A dataset in EPT will contain a lot of files, however, the ept.json file describes all the rest. The EPT file can be used in Potree and QGIS to view the point cloud.
-
Link to view the point cloud (using the Entwine Point Tile (EPT) format) in the 3D Potree viewer.
-
Link to the NV5 lidar report.
-
Link to the breaklines in Esri gdb and OGC GeoPackage formats.
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
-162.05° W,
-162° E,
60.23° N,
60.19° S
Eek collection area
2024-09-21
Eek date of collection
Item Identification
| Title: | 2024 NOAA Lidar: AK Coastal Communities (Eek, Goodnews Bay, Nelson Lagoon, Quinhagak, Togiak) |
|---|---|
| Short Name: | ak2024_cstl_comms_m10426 |
| Status: | Completed |
| Creation Date: | 2024 |
| Publication Date: | 2025 |
| Abstract: |
Original Product: Classified LAZ 1.4 files, formatted to 825 individual 750m x 750m tiles covering the NOAA AK Coastal Communities 2023 project area. Original Dataset Geographic Extent: This dataset and derived products encompass five areas covering approximately 92,475 acres of Southwest Alaska. Original Dataset Description: The NOAA AK Communities 2023 Lidar project called for the planning, acquisition, and processing of lidar data collected to Quality Level 1 (QL1) standards. Project specifications are based on the U.S. Geological Survey National Geospatial Program Lidar Base Specification Version 2023, Revision A. The data was developed based on the NAD83 2011 horizontal datum and the NAVD88 Geoid 12b vertical datum. Data was projected in UTM Zone 4N, Meters. Lidar data was delivered as calibrated and classified LAZ 1.4 files. Non-Vegetated Vertical Accuracy (NVA) was assessed using 101 check points located on bare earth in clear, unobstructed areas. Vegetated Vertical Accuracy (VVA) was assessed using 26 check points in Tall Grass, Forest, and Shrub landcover types. Single swath nominal pulse spacing (NPS) was designed to be 0.35 at nadir. Aggregate Nominal Pulse Spacing (ANPS) was calculated to be 0.269 with the Riegl VQ-780ii-S and 0.298 with the Riegl 1560iiS using all valid first return points. Derived products include: Intensity Imagery, Hydro-flattened Bare Earth Digital Elevation Models (DEMs), Maximum Surface Height Rasters (MSHRs), and 3D waters edge breaklines. Ground Condition: Ground conditions were free of snow and acquisition occurred free of smoke, fog and cloud cover. |
| Purpose: |
The purpose of the lidar data was to produce a high accuracy 3D dataset that meets all necessary standards laid out by the 3D Elevation Program and the NOAA AK Communities 2023 contract. The lidar point cloud data were used to create classified lidar LAZ files, intensity images, hydro-flattened DEMs, MSHRs, and 3D breaklines of rivers and lakes within the study area. |
| Supplemental Information: |
USGS Contract No. 1305M221DNCNP0018 CONTRACTOR: NV5 Geospatial. Ground Control Points were acquired by DOWL and calibrated by NV5 Geospatial. All lidar data acquisition, calibration, and follow-on processing were completed by NV5 Geospatial.
The following are the USGS lidar fields in JSON: {
"ldrinfo " :{
"ldrspec " :" U.S. Geological Survey National Geospatial Program Lidar Base Specification Version 2023, Revision A ", "ldrsens " :" Riegl VQ-780ii-S ", "ldrmaxnr " :" 14 ", "ldrnps " :" 0.35 ", "ldrdens " :" 8 ", "ldranps " :" 0.269 ", "ldradens " :" 13.843 ", "ldrfltht " :" 2058 ", "ldrfltsp " :" 145 ", "ldrscana " :" 58.5 ", "ldrscanr " :" Uniform Point Spacing ", "ldrpulsr " :" 1285 ", "ldrpulsd " :" 3 ", "ldrpulsw " :" 0.473 ", "ldrwavel " :" 1064 ", "ldrmpia " :" 1 ", "ldrbmdiv " :" 0.23 ", "ldrswatw " :" 2305 ", "ldrswato " :" 57 ", "ldrgeoid " :" Geoid 12b " }, "ldrinfo " :{
"ldrspec " :" U.S. Geological Survey National Geospatial Program Lidar Base Specification Version 2023, Revision A ", "ldrsens " :" Riegl 1560iiS ", "ldrmaxnr " :" 7 ", "ldrnps " :" 0.35 ", "ldrdens " :" 8 ", "ldranps " :" 0.298 ", "ldradens " :" 11.25 ", "ldrfltht " :" 2478 ", "ldrfltsp " :" 160 ", "ldrscana " :" 58.5 ", "ldrscanr " :" Uniform Point Spacing ", "ldrpulsr " :" 829 ", "ldrpulsd " :" 3 ", "ldrpulsw " :" 0.421 ", "ldrwavel " :" 1064 ", "ldrmpia " :" 1 ", "ldrbmdiv " :" 0.23 ", "ldrswatw " :" 2775 ", "ldrswato " :" 57 ", "ldrgeoid " :" Geoid 12b " }, "ldraccur " :{
"ldrchacc " :" 1.74 ", "rawnva " :" 0.125 ", "rawnvan " :" 101 " }, "lasinfo " :{
"lasver " :" 1.4 ", "lasprf " :" 6 ", "laswheld " :" Withheld (ignore) points are 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 " :" 1W ", "clasitem " :" Edge Clip " }, "lasclass " :{
"clascode " :" 2 ", "clasitem " :" Bare earth ground " }, "lasclass " :{
"clascode " :" 5 ", "clasitem " :" High Vegetation " }, "lasclass " :{
"clascode " :" 6 ", "clasitem " :" Building " }, "lasclass " :{
"clascode " :" 7W ", "clasitem " :" Low Noise " }, "lasclass " :{
"clascode " :" 9 ", "clasitem " :" Water " }, "lasclass " :{
"clascode " :" 17 ", "clasitem " :" Bridge Decks " }, "lasclass " :{
"clascode " :" 18W ", "clasitem " :" High Noise " }, "lasclass " :{
"clascode " :" 20 ", "clasitem " :" Ignored Ground Near Breaklines " } } } |
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 > 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
|
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: | NOAA Office for Coastal Management (OCM), NV5 Geospatial |
Support Roles
Data Steward
| Date Effective From: | 2025 |
|---|---|
| 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: | 2025 |
|---|---|
| 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: | 2025 |
|---|---|
| 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: | 2025 |
|---|---|
| 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 Description: |
Eek |
|---|
Extent Group 1 / Geographic Area 1
| W° Bound: | -162.05 | |
|---|---|---|
| E° Bound: | -162 | |
| N° Bound: | 60.23 | |
| S° Bound: | 60.19 | |
| Description |
Eek collection area |
|
Extent Group 1 / Time Frame 1
| Time Frame Type: | Discrete |
|---|---|
| Start: | 2024-09-21 |
| Description: |
Eek date of collection |
Extent Group 2
| Extent Description: |
Quinhagak |
|---|
Extent Group 2 / Geographic Area 1
| W° Bound: | -161.94 | |
|---|---|---|
| E° Bound: | -161.72 | |
| N° Bound: | 59.79 | |
| S° Bound: | 59.68 | |
| Description |
Quinhagak collection area |
|
Extent Group 2 / Time Frame 1
| Time Frame Type: | Discrete |
|---|---|
| Start: | 2024-09-22 |
| Description: |
Quinhagak collection date |
Extent Group 3
| Extent Description: |
Goodnews Bay |
|---|
Extent Group 3 / Geographic Area 1
| W° Bound: | -161.62 | |
|---|---|---|
| E° Bound: | -161.54 | |
| N° Bound: | 59.14 | |
| S° Bound: | 59.1 | |
| Description |
Goodnews Bay collection area |
|
Extent Group 3 / Time Frame 1
| Time Frame Type: | Discrete |
|---|---|
| Start: | 2024-09-21 |
| Description: |
Goodnews Bay collection date |
Extent Group 4
| Extent Description: |
Togiak |
|---|
Extent Group 4 / Geographic Area 1
| W° Bound: | -160.56 | |
|---|---|---|
| E° Bound: | -160.24 | |
| N° Bound: | 59.13 | |
| S° Bound: | 58.98 | |
| Description |
Togiak collection area |
|
Extent Group 4 / Time Frame 1
| Time Frame Type: | Discrete |
|---|---|
| Start: | 2023-10-02 |
| Description: |
Togiak collection date |
Extent Group 4 / Time Frame 2
| Time Frame Type: | Discrete |
|---|---|
| Start: | 2024-07-31 |
| Description: |
Togiak collection date |
Extent Group 5
| Extent Description: |
Nelson Lagoon |
|---|
Extent Group 5 / Geographic Area 1
| W° Bound: | -161.46 | |
|---|---|---|
| E° Bound: | -161.07 | |
| N° Bound: | 56.02 | |
| S° Bound: | 55.9 | |
| Description |
Nelson Lagoon collection area |
|
Extent Group 5 / Time Frame 1
| Time Frame Type: | Discrete |
|---|---|
| Start: | 2024-08-20 |
Spatial Information
Spatial Representation
Representations Used
| Grid: | No |
|---|---|
| Vector: | Yes |
| Text / Table: | No |
| TIN: | No |
| Stereo Model: | No |
| Video: | No |
Reference Systems
Reference System 1
Coordinate Reference System |
|||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||
Access Information
| Data License: | Universal (CC0 1.0) Public Domain Dedication |
|---|---|
| Data License URL: | https://creativecommons.org/publicdomain/zero/1.0/ |
| Data License Statement: |
To the extent possible under law, the U.S. Government has waived all copyright and related or neighboring rights to this dataset. |
| Security Class: | Unclassified |
| 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
| Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=10426/details/10426 |
|---|---|
| Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2025 - 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. |
| Distribution Format: | Not Applicable |
| Compression: | Zip |
Distribution 2
| Download URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/10426/index.html |
|---|---|
| Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2025 - Present) |
| File Name: | Bulk Download |
| Description: |
Bulk download of data files in LAZ format, UTM Zone 4N NAD83(2011) meters coordinates and elevations in NAVD88(GEOID12B) meters. |
| Distribution Format: | LAS/LAZ - LASer |
| Compression: | LAZ |
URLs
URL 1
| 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
| URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/entwine/geoid12b/10426/ept.json |
|---|---|
| Name: | Entwine Point Tile (EPT) |
| URL Type: |
Online Resource
|
| File Resource Format: | json |
| Description: |
Entwine Point Tile (EPT) is a simple and flexible octree-based storage format for point cloud data. The data is organized in such a way that the data can be reasonably streamed over the internet, pulling only the points you need. EPT files can be queried to return a subset of the points that give you a representation of the area. As you zoom further in, you are requesting higher and higher densities. A dataset in EPT will contain a lot of files, however, the ept.json file describes all the rest. The EPT file can be used in Potree and QGIS to view the point cloud. |
URL 3
| URL: | https://coast.noaa.gov/lidar/viewer/v/noaapotree.html?r=https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/entwine/geoid12b/10426/ept.json |
|---|---|
| Name: | Potree 3D View |
| URL Type: |
Online Resource
|
| Description: |
Link to view the point cloud (using the Entwine Point Tile (EPT) format) in the 3D Potree viewer. |
URL 4
| URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/10418/supplemental/AK_Communities_2025_NIR_lidar_Report.pdf |
|---|---|
| Name: | Lidar Report |
| URL Type: |
Online Resource
|
| File Resource Format: | |
| Description: |
Link to the NV5 lidar report. |
URL 5
| URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/10426/breaklines/index.html |
|---|---|
| Name: | Breaklines |
| URL Type: |
Online Resource
|
| Description: |
Link to the breaklines in Esri gdb and OGC GeoPackage formats. |
Technical Environment
| Description: |
LiDAR Mapping Suite 2.4, Applanix PosPac 9.1, Microstation CONNECT version, TerraScan Version 20, TerraModeler Version 20, TerraMatch Version 20, ESRI ArcGIS 10.8, Windows 10 Operating System |
|---|
Data Quality
| Horizontal Positional Accuracy: |
Lidar horizontal accuracy is a function of Global Navigation Satellite System (GNSS) derived positional error, flying altitude, and INS derived attitude error. The obtained RMSEr value is multiplied by a conversion factor of 1.7308 to yield the horizontal component of the National Standards for Spatial Data Accuracy (NSSDA) reporting standard where a theoretical point will fall within the obtained radius 95 percent of the time. Based on a flying altitude of 2478 meters for UTM Zone 4, an IMU error of 0.013 decimal degrees, and a GNSS positional error of 0.027 meters, this project was produced to meet 1.742 meters horizontal accuracy at the 95% confidence level (1.006 m RMSEr). |
|---|---|
| Vertical Positional Accuracy: |
This data set was produced to meet ASPRS Positional Accuracy Standard for Digital Geospatial Data (2014) for a 10-cm RMSEz Vertical Accuracy Class. The NVA was tested with 101 independent check points located in open terrain 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. Specifications for this project require that the NVA be 0.196 meters or better AccuracyZ at 95% confidence level. The 101 independent NVA check points were surveyed using real-time kinematics (RTK) 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 0.031 meters resulting in an AccuracyZ at the 95% confidence level of 0.61 meters. NVA AccuracyZ has been tested and meets the required 0.196 meter NVA at 95% confidence level using (RMSEz * 1.9600) for the unclassified lidar point cloud as defined by the National Standards for Spatial Data Accuracy (NSSDA) and herein reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines. For the Coastal Communities survey for UTM Zone 4, 26 vegetated checkpoints were collected, with resulting vegetated vertical accuracy of 0.257 meters as compared to the classified LAS or 12.2 cm RMSE. |
| Completeness Report: |
These LAZ 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: |
Classified LAS files were tested by NV5 for vertical accuracy. All data is seamless from one tile to the next, no gaps or no data areas. |
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-NC |
| How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?: |
Data is backed up to cloud storage. |
Lineage
| Lineage Statement: |
This data was collected by NV5 Geospatial for the NOAA Office for Coastal Management (OCM). |
|---|
Sources
NOAA OCM Lidar
| Contact Role Type: | Originator |
|---|---|
| Contact Type: | Organization |
| Contact Name: | NOAA OCM |
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 Geoid 12b correction. 5. Import raw laser points into manageable blocks 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: | 2025-02-26 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 final NVA, VVA, and density information for the project using ground control quality check points. |
|---|---|
| Process Date/Time: | 2025-02-26 00:00:00 |
Process Step 3
| Description: |
During the NOAA OCM review of the data, the following issues were noted and are listed here for user awareness: 1. There are areas where points that are believed to be ground but were either left unclassified or classified as vegetation, including large boulders classified as high vegetation. The misclassified points result in errors in the DEMs. 2. Some narrow ridgelines and minor summits lack sufficient points classified as ground due to vegetation, leading to inaccurate truncation of these features. 3. There are areas with deep seasonal snow-cover, making it difficult to resolve alpine geomorphology. The NOAA Office for Coastal Management (OCM) processed 825 LAZ files collected by NV5 Geospatial. The files were in UTM Zone 4N NAD83(2011), meters coordinates and the elevations were in NAVD88 (GEOID12B) meters. The LAZ files had these classifications: 1 = unclassified; 2 = ground (or Bare Earth); 5 = high vegetation (greater than 2 m), 6 = buildings, 7 = low point (noise); 9 = water; 17 = bridges; 18 = high noise; 20 = ignored ground. Some of the class 1, and all of the class 7, and 18 points also had the withheld bit set. Those withheld points were not included in the OCM processing. NOAA OCM processed the 1, 2, 5, 6, 9, 17, and 20 point classes to the Digital Coast Data Access Viewer (DAV). OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. Internal OCM scripts were run to check the number of points by classification and by flight ID and the gps, elevation, and intensity ranges. 2. Internal OCM scripts were run on the laz files to: a. Convert from orthometric (NAVD88) elevations to ellipsoid elevations using the GEOID12B model b. Convert from UTM Zone 4N (NAD83 2011) meters coordinates to geographic coordinates c. Assign the geokeys, to sort the data by gps time and zip the data to database and to AWS S3. |
|---|---|
| Process Date/Time: | 2025-08-28 00:00:00 |
| Process Contact: | NOAA Office for Coastal Management (NOAA/OCM) |
| Email Address: | coastal.info@noaa.gov |
| Phone (Voice): | (843) 740-1202 |
Related Items
| Item Type | Relationship Type | Title |
|---|---|---|
| Data Set (DS) | Cross Reference |
2024 NOAA Lidar DEM: AK Coastal Communities (Eek, Goodnews Bay, Nelson Lagoon, Quinhagak, Togiak) |
Catalog Details
| Catalog Item ID: | 77595 |
|---|---|
| GUID: | gov.noaa.nmfs.inport:77595 |
| Metadata Record Created By: | Rebecca Mataosky |
| Metadata Record Created: | 2025-08-28 20:17+0000 |
| Metadata Record Last Modified By: | Rebecca Mataosky |
| Metadata Record Last Modified: | 2025-09-03 18:39+0000 |
| Metadata Record Published: | 2025-08-29 |
| Owner Org: | OCM |
| Metadata Publication Status: | Published Externally |
| Do Not Publish?: | N |
| Metadata Last Review Date: | 2025-08-29 |
| Metadata Review Frequency: | 1 Year |
| Metadata Next Review Date: | 2026-08-29 |