2019 USGS Topobathy Lidar: West Everglades National Park, FL
Data Set (DS) | OCM Partners (OCMP)GUID: gov.noaa.nmfs.inport:69463 | Updated: October 17, 2023 | Published / External
Summary
Short Citation
OCM Partners, 2025: 2019 USGS Topobathy Lidar: West Everglades National Park, FL, https://www.fisheries.noaa.gov/inport/item/69463.
Full Citation Examples
Product: These lidar data are processed Classified LAS 1.4 files, formatted to 2601 individual 1000 m x 1000 m tiles; used to create intensity images, 2D refraction extents, and Topobathy DEMs as necessary.
Geographic Extent: Collier, Monroe, and Miami-Dade counties, West Everglades, Florida, covering approximately 869 square miles.
Dataset Description: Florida West Everglades National Park 2018 Lidar project called for the Planning, Acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 meters. 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 a horizontal projection/datum of NAD83 (2011),Conus Albers, meters and vertical datum of NAVD88 (GEOID12B), meters. Lidar data were delivered as processed Classified LAS 1.4 files, formatted to 2601 individual 1000 m x 1000 m tiles, as tiled Intensity Imagery, and as tiled bare earth topobathy DEMs; all tiled to the same 1000 m x 1000 m schema.
Ground Conditions: Lidar was collected while no snow was on the ground and rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Leading Edge Geomatics established a total of 183 ground control points that were used to calibrate the lidar to known ground locations established throughout the Florida West Everglades National Park project area. Dewberry surveyed an additional 51 GCPs to test the calibrated swath data. Dewberry also surveyed 125 accuracy checkpoints to assess the vertical accuracy of the final data. Neither the Dewberry surveyed GCPs or checkpoints were used to calibrate or post process the data. Some surveyed points were placed in poor locations and had to be removed from accuracy testing. In order to meet ASPRS survey point requirements, 12 Dewberry surveyed GCPs were used in the final vertical accuracy testing. As the Dewberry surveyed GCPs were not used in any calibration processing and were only used to test calibrated data, all surveyed points used in final accuracy testing (Dewberry surveyed checkpoints and Dewberry surveyed GCPs) are an independent validation of the final calibrated, processed, and edited data. Additionally, one NVA point was actually located in vegetation so it was used to assess VVA despite its checkpoint ID name. A total of 113 surveyed points (55 NVA, 45 VVA, and 13 Bathymetric Bottom) were used in the final accuracy testing. This delivery is for the full project AOI and consists of 2601 lidar tiles.
This metadata record reflects the data that are available from the NOAA Digital Coast Data Access Viewer (DAV).
The NOAA Office for Coastal Management (OCM) downloaded 2601 laz point data files from this USGS site:
https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/FL_WestEvergladesNP_2018_B18/FL_WestEvergladesNP_topobathymetric_2018/LAZ/
The data were processed to the NOAA Digital Coast Data Access Viewer (DAV) to make the data available for custom downloads.
Distribution Information
-
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, based on a horizontal datum/projection of Albers Equal Area, NAD83(2011), meters and a vertical datum of NAVD88 (GEOID12B) and units in meters. This url links to the USGS copy of the files. These have not been reviewed by OCM and the link is provided here for convenience.
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 BATHYMETRY, COASTAL ELEVATION, elevation, TERRAIN 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
-81.532506° W,
-80.588105° E,
25.900585° N,
25.105556° S
2019-03-02 - 2019-07-04
Item Identification
Title: | 2019 USGS Topobathy Lidar: West Everglades National Park, FL |
---|---|
Short Name: | fl2019_w_ever_m9780_metadata |
Status: | Completed |
Creation Date: | 2019 |
Publication Date: | 2020-11-20 |
Abstract: |
Product: These lidar data are processed Classified LAS 1.4 files, formatted to 2601 individual 1000 m x 1000 m tiles; used to create intensity images, 2D refraction extents, and Topobathy DEMs as necessary. Geographic Extent: Collier, Monroe, and Miami-Dade counties, West Everglades, Florida, covering approximately 869 square miles. Dataset Description: Florida West Everglades National Park 2018 Lidar project called for the Planning, Acquisition, processing and derivative products of lidar data to be collected at a nominal pulse spacing (NPS) of 0.35 meters. 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 a horizontal projection/datum of NAD83 (2011),Conus Albers, meters and vertical datum of NAVD88 (GEOID12B), meters. Lidar data were delivered as processed Classified LAS 1.4 files, formatted to 2601 individual 1000 m x 1000 m tiles, as tiled Intensity Imagery, and as tiled bare earth topobathy DEMs; all tiled to the same 1000 m x 1000 m schema. Ground Conditions: Lidar was collected while no snow was on the ground and rivers were at or below normal levels. In order to post process the lidar data to meet task order specifications and meet ASPRS vertical accuracy guidelines, Leading Edge Geomatics established a total of 183 ground control points that were used to calibrate the lidar to known ground locations established throughout the Florida West Everglades National Park project area. Dewberry surveyed an additional 51 GCPs to test the calibrated swath data. Dewberry also surveyed 125 accuracy checkpoints to assess the vertical accuracy of the final data. Neither the Dewberry surveyed GCPs or checkpoints were used to calibrate or post process the data. Some surveyed points were placed in poor locations and had to be removed from accuracy testing. In order to meet ASPRS survey point requirements, 12 Dewberry surveyed GCPs were used in the final vertical accuracy testing. As the Dewberry surveyed GCPs were not used in any calibration processing and were only used to test calibrated data, all surveyed points used in final accuracy testing (Dewberry surveyed checkpoints and Dewberry surveyed GCPs) are an independent validation of the final calibrated, processed, and edited data. Additionally, one NVA point was actually located in vegetation so it was used to assess VVA despite its checkpoint ID name. A total of 113 surveyed points (55 NVA, 45 VVA, and 13 Bathymetric Bottom) were used in the final accuracy testing. This delivery is for the full project AOI and consists of 2601 lidar tiles. This metadata record reflects the data that are available from the NOAA Digital Coast Data Access Viewer (DAV). The NOAA Office for Coastal Management (OCM) downloaded 2601 laz point data files from this USGS site: https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/FL_WestEvergladesNP_2018_B18/FL_WestEvergladesNP_topobathymetric_2018/LAZ/ The data were processed to the NOAA Digital Coast Data Access Viewer (DAV) to make the data available for custom downloads. |
Purpose: |
The primary purpose of this project was to support the National Park Service with high-accuracy light detection and ranging (lidar) technology for the USGS FL West Everglades NP project area. |
Supplemental Information: |
USGS Contract No. G16PC00020 CONTRACTOR: Dewberry, Inc. SUBCONTRACTOR: Leading Edge Geomatics. Lidar data were acquired and calibrated by Leading Edge Geomatics. All follow-on processing was completed by Dewberry.
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" : "Riegl VQ880-G", "ldrmaxnr" : "7", "ldrnps" : "0.5", "ldrdens" : "4", "ldranps" : "0.35", "ldradens" : "8", "ldrfltht" : "500", "ldrfltsp" : "130", "ldrscana" : "40", "ldrscanr" : "80", "ldrpulsr" : "245", "ldrpulsd" : "1.5", "ldrpulsw" : "0.45", "ldrwavel" : "532", "ldrmpia" : "1", "ldrbmdiv" : "0.7", "ldrswatw" : "364", "ldrswato" : "55", "ldrgeoid" : "g2012Bu0.bin" }, "ldrinfo" : {
"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification v1.3", "ldrsens" : "Riegl VQ880-G", "ldrmaxnr" : "7", "ldrnps" : "0.58", "ldrdens" : "3", "ldranps" : "0.41", "ldradens" : "6", "ldrfltht" : "500", "ldrfltsp" : "130", "ldrscana" : "40", "ldrscanr" : "137", "ldrpulsr" : "245", "ldrpulsd" : "3", "ldrpulsw" : "0.9", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.3", "ldrswatw" : "364", "ldrswato" : "55", "ldrgeoid" : "g2012Bu0.bin" }, "ldrinfo" : {
"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification v1.3", "ldrsens" : "Riegl VQ880-GII", "ldrmaxnr" : "7", "ldrnps" : "0.41", "ldrdens" : "6", "ldranps" : "0.41", "ldradens" : "6", "ldrfltht" : "450", "ldrfltsp" : "130", "ldrscana" : "40", "ldrscanr" : "80", "ldrpulsr" : "200", "ldrpulsd" : "1.5", "ldrpulsw" : "0.45", "ldrwavel" : "532", "ldrmpia" : "1", "ldrbmdiv" : "0.7", "ldrswatw" : "328", "ldrswato" : "20", "ldrgeoid" : "g2012Bu0.bin" }, "ldrinfo" : {
"ldrspec" : "U.S. Geological Survey (USGS) - National Geospatial Program (NGP) Lidar Base Specification v1.3", "ldrsens" : "Riegl VQ880-GII", "ldrmaxnr" : "7", "ldrnps" : "0.5", "ldrdens" : "4", "ldranps" : "0.5", "ldradens" : "4", "ldrfltht" : "450", "ldrfltsp" : "130", "ldrscana" : "40", "ldrscanr" : "142", "ldrpulsr" : "300", "ldrpulsd" : "3", "ldrpulsw" : "0.9", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.3", "ldrswatw" : "328", "ldrswato" : "20", "ldrgeoid" : "g2012Bu0.bin" }, "ldraccur" : {
"ldrchacc" : "1", "rawnva" : "0.131", "rawnvan" : "55", "clsnva" : "0.131", "clsnvan" : "55", "clsvva" : "0.246", "clsvvan" : "45" }, "lasinfo" : {
"lasver" : "1.4", "lasprf" : "6", "laswheld" : "Withheld (ignore) points were identified in these files using the standard LAS Withheld bit.", "lasolap" : "No swath "overage" points were identified in these files; the standard LAS overlap bit was not used.", "lasintr" : "16", "lasclass" : {
"clascode" : "1", "clasitem" : "Processed, but Unclassified" }, "lasclass" : {
"clascode" : "2", "clasitem" : "Bare Earth Ground" }, "lasclass" : {
"clascode" : "7", "clasitem" : "Low Noise" }, "lasclass" : {
"clascode" : "17", "clasitem" : "Bridge Decks" }, "lasclass" : {
"clascode" : "18", "clasitem" : "High Noise" }, "lasclass" : {
"clascode" : "40", "clasitem" : "Bathymetric Bottom" }, "lasclass" : {
"clascode" : "41", "clasitem" : "Bathymetric Water Surface" }, "lasclass" : {
"clascode" : "45", "clasitem" : "Water Column/No Bathymetric Bottom Found" } }} |
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 > FLORIDA
|
Global Change Master Directory (GCMD) Location Keywords |
VERTICAL LOCATION > LAND SURFACE
|
Global Change Master Directory (GCMD) Location Keywords |
VERTICAL LOCATION > SEA FLOOR
|
UNCONTROLLED | |
None | Collier County |
None | Miami-Dade County |
None | Monroe County |
None | West Everglades |
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: | Dewberry, USGS |
Support Roles
Data Steward
Date Effective From: | 2023 |
---|---|
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: | 2023 |
---|---|
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: | 2019 |
---|---|
Date Effective To: | |
Contact (Organization): | U.S. Geological Survey |
Address: |
12201 Sunrise Valley Drive Reston, VA 20191 USA |
URL: | USGS Home |
Metadata Contact
Date Effective From: | 2023 |
---|---|
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: | 2023 |
---|---|
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
W° Bound: | -81.532506 | |
---|---|---|
E° Bound: | -80.588105 | |
N° Bound: | 25.900585 | |
S° Bound: | 25.105556 |
Extent Group 1 / Time Frame 1
Time Frame Type: | Range |
---|---|
Start: | 2019-03-02 |
End: | 2019-07-04 |
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 |
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|
Access Information
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
Start Date: | 2023-03-23 |
---|---|
End Date: | Present |
Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9780/details/9780 |
Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2023 - 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
Start Date: | 2019 |
---|---|
End Date: | Present |
Download URL: | https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/FL_WestEvergladesNP_2018_B18/FL_WestEvergladesNP_topobathymetric_2018/LAZ/ |
Distributor: | U.S. Geological Survey (2019 - Present) |
File Name: | Bulk Download |
Description: |
Bulk download of data files in LAZ format, based on a horizontal datum/projection of Albers Equal Area, NAD83(2011), meters and a vertical datum of NAVD88 (GEOID12B) and units in meters. This url links to the USGS copy of the files. These have not been reviewed by OCM and the link is provided here for convenience. |
File Type (Deprecated): | LAZ |
Distribution Format: | LAS/LAZ - LASer |
Compression: | Zip |
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://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/metadata/FL_WestEvergladesNP_2018_B18/ |
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Name: | USGS Additional Info |
URL Type: |
Online Resource
|
Description: |
Link to the reports, breaklines, metadata, spatial metadata, and shapefiles. |
URL 3
URL: | https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/metadata/FL_WestEvergladesNP_2018_B18/USGS_FL_WestEvergladesNP_2018_B18_Project_Report.pdf |
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Name: | USGS Project Report |
URL Type: |
Online Resource
|
File Resource Format: | |
Description: |
Link to the USGS project report which provides information about the project, the vertical accuracy results, the point classifications and the sensors used. |
URL 4
URL: | https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/metadata/FL_WestEvergladesNP_2018_B18/FL_WestEvergladesNP_topobathymetric_2018/reports/W_Everglades_NP_Lidar_Mapping_Report.pdf |
---|---|
Name: | Lidar Report |
URL Type: |
Online Resource
|
File Resource Format: | |
Description: |
Link to the lidar report. |
URL 5
URL: | https://s3-us-west-2.amazonaws.com/usgs-lidar-public/FL_WestEvergladesNP_topobathymetric_2018/ept.json |
---|---|
Name: | USGS 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 6
URL: | https://usgs.entwine.io/data/view.html?r=%22https://s3-us-west-2.amazonaws.com/usgs-lidar-public/FL_WestEvergladesNP_topobathymetric_2018%22 |
---|---|
Name: | 3D View (USGS Potree) |
URL Type: |
Online Resource
|
Description: |
Link to view the point cloud (using the Entwine Point Tile (EPT) format) in the 3D Potree viewer. |
Technical Environment
Description: |
Riegl RiProcess; Microstation; Terrascan; ArcGIS 10.6.1; Windows 8; .las |
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Data Quality
Horizontal Positional Accuracy: |
Horizontal accuracy testing requires well-defined checkpoints that can be visually identified in the dataset. Elevation datasets, including lidar datasets, do not always contain well-defined checkpoints suitable for horizontal accuracy assessment. Dewberry reviewed all NVA checkpoints to determine which, if any, of these checkpoints were located on photo-identifiable features in the intensity imagery. No checkpoints were photo-identifiable in the intensity imagery; horizontal accuracy could not be tested on this dataset. This data set was produced to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 41 cm RMSEx/RMSEy horizontal accuracy class which equates to a positional horizontal accuracy = +/- 1 meter at the 95% confidence level. |
---|---|
Vertical Positional Accuracy: |
USGS Determined Vertical Accuracy Non-Vegetated Vertical Accuracy (NVA) = 6.4. cm RMSE Vegetated Vertical Accuracy (VVA) = 25.09 cm at the 95th Percentile Bathymetric Vertical Accuracy = 30.49 cm at the 95% Confidence Level Refer to the USGS project report in the URL section of this metadata record. |
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 missing data exist. |
Conceptual Consistency: |
Data covers the entire area specified for this project. |
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
Lineage Statement: |
Data were collected and processed by Dewberry and Leading Edge Geomatics and were made available on the USGS ftp site. The data were downloaded from the USGS rockyweb site by the NOAA Office for Coastal Management (OCM) where the data were processed to make it available for custom download from the NOAA Digital Coast Data Access Viewer (DAV). |
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Sources
USGS
Contact Role Type: | Publisher |
---|---|
Contact Type: | Organization |
Contact Name: | USGS |
Citation URL: | https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/FL_WestEvergladesNP_2018_B18/FL_WestEvergladesNP_topobathymetric_2018/LAZ/ |
Citation URL Name: | USGS Rockyweb download site |
Process Steps
Process Step 1
Description: |
The boresight for each lift was done individually as the solution may change slightly from lift to lift. The following steps describe the Raw Data Processing and Boresight process: 1) Technicians processed the raw data to LAS format flight lines using the final GPS/IMU solution. This LAS data set was used as source data for boresight. 2) Technicians first used commercial software to calculate initial boresight adjustment angles based on sample areas selected in the lift. These areas cover calibration flight lines collected in the lift, cross tie and production flight lines. These areas are well distributed in the lift coverage and cover multiple terrain types that are necessary for boresight angle calculation. The technician then analyzed the results and made any necessary additional adjustment until it is acceptable for the selected areas. 3) Once the boresight angle calculation was completed for the selected areas, the adjusted settings were applied to all of the flight lines of the lift and checked for consistency. The technicians utilized commercial and proprietary software packages to analyze how well flight line overlaps match for the entire lift and adjusted as necessary until the results met the project specifications. 4) Once all lifts were completed with individual boresight adjustment, the technicians checked and corrected the vertical misalignment of all flight lines and also the matching between data and ground truth. The relative accuracy was less than or equal to 6 cm RMSDz within individual swaths and less than or equal to 8 cm RMSDz or within swath overlap (between adjacent swaths). The sensors utilized on this project had both a NIR laser and a green laser so intraswath analyses, including intraswath polygon generation and review, were performed for each laser separately. The eastern add-on portion of the FL West Everglades NP project area was particularly difficult to align due to relatively few hard surfaces present which could reliably be used during the alignment process. Only one road is present in this add-on area. Due to the nature of relative swath alignment being based off the ground surface within each swath (which in reality is just the lowest plane of points), the process of using the lowest points can introduce some discrepancies due to these assumptions. In some areas one sensor may penetrate the vegetation to a greater extent, resulting in a lower last return surface. The alignment process bases the corrections from the statistical trends found in these offsets. This means that if there is a much greater coverage of vegetated areas than hard surfaces, those vegetated areas can have a much larger impact on the relative alignment of the data. In the case of this area the discrepancy resulted in a misalignment along a portion of the roadway while the vegetated areas nearby show no misalignment. Examining the park road in the east of the project shows that several of the swaths have some bias between the NIR and green swaths (approximately 7-11 cm), but there are 3-4 flightlines with larger offsets approaching 15 cm. Areas along the road exhibiting the most measureable offsets are identified in the provided shapefile, named W_Everglades_NP_Lidar_Interswath_Issues. Please see the project report for more details on interswath and intraswath testing and review. 5) The technicians ran a final vertical accuracy check of the boresighted flight lines against the surveyed check points to ensure the requirement of NVA = 19.6 cm 95% Confidence Level (Required Accuracy) is met. Point classification was performed according to USGS Lidar Base Specification 1.3 including the addition of bathy domain classes. Refraction extents (2D) were generated from the refracted lidar points. Topobathy DEMs were generated from the classified point cloud. |
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Process Date/Time: | 2020-07-01 00:00:00 |
Process Step 2
Description: |
Automated grounding was performed using Terrascan software. This routine classifies any obvious low outliers in the dataset to class 7 and high outliers in the dataset to class 18. Points along flight line edges that are geometrically unusable are identified by their scan angle and classified to a separate class so that they will not be used in the initial ground algorithm. These point with higher scan angles will be set to withheld later in the lidar processing. After points that could negatively affect the ground are removed from class 1, the ground layer is extracted from this remaining point cloud. The ground extraction process encompassed in this routine takes place by building an iterative surface model. The final refraction extents are then used to classify ground points within the refraction extents as bathymetric bottom. The refraction extents are also used as part of the classification routines to ensure water surface and water column points are classified correctly. Each tile was then imported into Terrascan and a surface model was created to examine the ground (class 2) and bathy bottom (class 40) classification. Dewberry analysts employ 3D visualization techniques to view the point cloud at multiple angles and in profile to ensure that non-ground points are removed from the ground classification and that class 40 accurately represents submerged topography. Dewberry analysts visually reviewed the surface models and corrected errors in the ground classification such as vegetation, buildings, and bridges that were present following the initial processing conducted by Dewberry. Bridge decks are manually classified to class 17. The withheld bit is set on the points with higher scan angles previously identified in Terrascan before the ground classification routine was performed. After manual classification, the LAS tiles were peer reviewed and then underwent a final QA/QC. After the final QA/QC and corrections, all headers, appropriate point data records, and variable length records, including spatial reference information, are updated in proprietary software and then verified using proprietary Dewberry tools. |
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Process Date/Time: | 2020-09-01 00:00:00 |
Process Step 3
Description: |
Due to two lasers being utilized per each sensor and the high amount of overlap, the average calculated (A)NPD is much hihger than the project requirements of 0.35 meter NPS and 8 points per square meter (ppsm). A portion of this project was funded after the original Task Order, as an add-on. The average calculated (A)NPD of the original AOI is 23 ppsm (0.21 m NPS) and the average (A)NPD of the add-on portion of this AOI is 14 ppsm (0.27 m NPS). The average density was tested on the LAS data using geometrically reliable (withheld and noise points excluded) first-return points. (A)NPD was tested using rasters which calculate the average number of points within each cell. |
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Process Date/Time: | 2020-08-01 00:00:00 |
Process Step 4
Description: |
The NOAA Office for Coastal Management (OCM) downloaded 2601 laz point data files from this USGS site: https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/LPC/Projects/FL_WestEvergladesNP_2018_B18/FL_WestEvergladesNP_topobathymetric_2018/LAZ/ The data were in Albers Equal Area (NAD83 2011), meters coordinates and NAVD88 (Geoid12B) elevations in meters. The data were classified as: 1 - Unclassified, 2 - Ground, 7 - Low Noise, 17 - Bridge Decks, 18 - High Noise, 40 - Bathymetric Bottom, 41 - Water Surface, 45 - No bathymetric bottom found (water column). OCM processed all classifications of points to the Digital Coast Data Access Viewer (DAV). Classes available on the DAV are: 1, 2, 7, 17, 18, 40, 41, 45. 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 NAD83 (2011) ellipsoid elevations using the Geoid12B model b. Convert the laz files from Albers Equal Area (NAD83 2011), meters coordinates to geographic coordinates c. Assign the geokeys, sort the data by gps time and zip the data to database. |
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Process Date/Time: | 2023-03-22 00:00:00 |
Process Contact: | Office for Coastal Management (OCM) |
Catalog Details
Catalog Item ID: | 69463 |
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GUID: | gov.noaa.nmfs.inport:69463 |
Metadata Record Created By: | Rebecca Mataosky |
Metadata Record Created: | 2023-03-23 13:50+0000 |
Metadata Record Last Modified By: | SysAdmin InPortAdmin |
Metadata Record Last Modified: | 2023-10-17 16:12+0000 |
Metadata Record Published: | 2023-03-23 |
Owner Org: | OCMP |
Metadata Publication Status: | Published Externally |
Do Not Publish?: | N |
Metadata Last Review Date: | 2023-03-23 |
Metadata Review Frequency: | 1 Year |
Metadata Next Review Date: | 2024-03-23 |