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Data Set Info
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Spatial Info
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Distribution Info
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Catalog Details

Summary

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Short Citation
National Geodetic Survey, 2024: 2019 NOAA NGS Topobathy Lidar: U.S. Virgin Islands, https://www.fisheries.noaa.gov/inport/item/65631.
Full Citation Examples

Abstract

These data were collected by Leading Edge Geomatics using a Riegl VQ-880-G II sensor. The data acqusition began January 20, 2019 through June 2, 2019. The data includes topobathy data in LAS 1.4 format classified as created, never classified (0); unclassified (1); ground (2); noise (7); bathymetric bottom (40); water surface (41); derived water surface (42); submerged object, not otherwise specified (e.g., wreck, rock, submerged piling) (43); International Hydrographic Organization S-57 object, not otherwise specified (44); no bottom found (bathymetric lidar point for which no detectable bottom return was received) (45); bathymetic bottom temporal changes (46) in accordance with project specifications.

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, 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.

Access Constraints:

None

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be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions.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.

Controlled Theme Keywords

BATHYMETRY, BEACHES, COASTAL BATHYMETRY, COASTAL ELEVATION, DIGITAL ELEVATION/TERRAIN MODEL (DEM), elevation, LAND SURFACE, LIDAR, TERRAIN ELEVATION, TOPOGRAPHY

Contact Information

Metadata Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202

Extents

Geographic Area 1

-65.16° W, -64.534435° E, 18.528116° N, 17.626749° S

Data only covers coastal area.

Time Frame 1
2019-01-20 - 2019-06-02

Item Identification

Title: 2019 NOAA NGS Topobathy Lidar: U.S. Virgin Islands
Status: Completed
Publication Date: 2021
Abstract:

These data were collected by Leading Edge Geomatics using a Riegl VQ-880-G II sensor. The data acqusition began January 20, 2019 through June 2, 2019. The data includes topobathy data in LAS 1.4 format classified as created, never classified (0); unclassified (1); ground (2); noise (7); bathymetric bottom (40); water surface (41); derived water surface (42); submerged object, not otherwise specified (e.g., wreck, rock, submerged piling) (43); International Hydrographic Organization S-57 object, not otherwise specified (44); no bottom found (bathymetric lidar point for which no detectable bottom return was received) (45); bathymetic bottom temporal changes (46) in accordance with project specifications.

Purpose:

The US Virgin Islands have been identified as having cirtical topographic and bathymetric data gaps by NOAA. This lidar data will fill those critical gaps.

Supplemental Information:

The full workflow used for this project is found in the final project report submitted to NOAA.

Keywords

Theme Keywords

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

Spatial Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Location Keywords
OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > CARIBBEAN SEA > VIRGIN ISLANDS

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: National Oceanic and Atmospheric Administration (NOAA), National Geodetic Survey (NGS), Remote Sensing Division (RSD), Coastal Mapping Program (CMP)

Support Roles

Data Steward

CC ID: 1091848
Date Effective From: 2021
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: 1091846
Date Effective From: 2021
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: 1091847
Date Effective From: 2021
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

Originator

CC ID: 1091849
Date Effective From: 2021
Date Effective To:
Contact (Organization): National Geodetic Survey (NGS)
Address: 1315 East-West Hwy
Silver Spring, MD 20910
URL: https://geodesy.noaa.gov/

Extents

Currentness Reference: Ground Condition

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 1146460
W° Bound: -65.16
E° Bound: -64.534435
N° Bound: 18.528116
S° Bound: 17.626749
Description

Data only covers coastal area.

Extent Group 1 / Time Frame 1

CC ID: 1146459
Time Frame Type: Range
Start: 2019-01-20
End: 2019-06-02

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

CC ID: 1146457

Coordinate Reference System

CRS Type: Geographic 3D
EPSG Code: EPSG:6319
EPSG Name: NAD83(2011)
See Full Coordinate Reference System Information

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: 1091850
Start Date: 2021-05
End Date: Present
Download URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9413
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2021 - 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: 1091851
Start Date: 2020-05
End Date: Present
Download URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9413/
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2021 - 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: 1091852
URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9413/supplemental/extent_ngs_vi_topobathy_m9413.kmz
Name: Browse graphic
URL Type:
Browse Graphic
File Resource Format: KML
Description:

This graphic displays the footprint for this lidar data set.

URL 2

CC ID: 1091853
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 3

CC ID: 1091854
URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/9413/supplemental/PR1801_VI1801_TB_C_Topobathy_Lidar_Project_Report_Final.pdf
Name: Project Report
URL Type:
Online Resource
File Resource Format: pdf
Description:

Topobathymetric Lidar Data Report

Technical Environment

Description:

OS Independent

Data Quality

Horizontal Positional Accuracy:

Only checkpoints photo-identifiable in the intensity imagery can be used to test the horizontal accuracy of the lidar. Photo-identifiable checkpoints in intensity imagery typically include checkpoints located at the ends of paint stripes on concrete or asphalt surfaces or checkpoints located at 90 degree corners of different reflectivity, e.g. a sidewalk corner adjoining a grass surface. The xy coordinates of checkpoints, as defined in the intensity imagery, are compared to surveyed xy coordinates for each photo-identifiable checkpoint. These differences are used to compute the tested horizontal accuracy of the lidar. As not all projects contain photo-identifiable checkpoints, the horizontal accuracy of the lidar cannot always be tested. Lidar vendors calibrate their lidar systems during installation of the system and then again for every project acquired. Typical calibrations include cross flights that capture features from multiple directions that allow adjustments to be performed so that the captured features are consistent between all swaths and cross flights from all directions. 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 Positional Horizontal Accuracy = +/- 1 meter at a 95% confidence level.

Thirty-one checkpoints were photo-identifiable. Using this small sample set of photo-identifiable checkpoints, positional accuracy of this dataset was found to be RMSEx = 31.1 cm and RMSEy = 25.4 cm which equates to ACCURACYr = 69.6 cm at 95% confidence level. The results of the small sample set of checkpoints are within the produced to meet horizontal accuracy criteria.

Vertical Positional Accuracy:

The vertical accuracy of the classified lidar was tested by Dewberry with 259 independent survey checkpoints. The survey checkpoints are evenly distributed throughout the project area and are located in areas of non-vegetated terrain, including bare earth, open terrain, and urban terrain (131); vegetated terrain, including forest, brush, tall weeds, crops, and high grass (94); and submerged bottom areas (34). The vertical accuracy is tested by comparing survey checkpoints to a triangulated irregular network (TIN) that is created from the lidar ground and submerged bottom points. Checkpoints are always compared to interpolated surfaces created from the lidar point cloud because it is unlikely that a survey checkpoint will be located at the precise location of a discrete lidar point. All checkpoints located in non-vegetated terrain were used to compute the Non-vegetated Vertical Accuracy (NVA). Project specifications require a NVA of 0.196 at the 95% confidence level based on RMSEz (0.1) x 1.9600. All checkpoints located in vegetated terrain were used to compute the Vegetated Vertical Accuracy (VVA). Project specifications require a VVA of 0.294 based on the 95th percentile. All checkpoints located in bathymetric areas were used to compute an accuracy value for the bathymetric data. Project specifications require the vertical accuracy for bathymetric data to be 0.363 or better at the 95% confidence level based on RMSEz (0.185) x 1.9600.

This lidar dataset was tested to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 10 cm RMSEz Vertical Accuracy Class. Actual NVA accuracy was found to be RMSEz = 0.086, equating to +/- 0.168 at 95% confidence level.

This lidar dataset was tested to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 10 cm RMSEz Vertical Accuracy Class. Actual VVA accuracy was found to be +/- 25.1 cm at the 95th percentile. The 5% outliers consisted of 5 checkpoints that are larger than the 95th percentile. These checkpoints had a DZ value of 37.3 cm, 42.3 cm, 35.1 cm, 25.9 cm, and 28.6 cm.

This lidar dataset was tested to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 18.5 cm RMSEz Vertical Accuracy Class. Actual Bathymetric accuracy was found to be RMSEz = 12.1 cm, equating to +/- 0.236 at the 95% confidence level.

Completeness Report:

Data covers the project boundary.

Conceptual Consistency:

Not applicable

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

Acquisition

CC ID: 1146452
Contact Role Type: Originator
Contact Type: Organization
Contact Name: Leading Edge Geomatics

Processing

CC ID: 1146453
Contact Role Type: Originator
Contact Type: Organization
Contact Name: Dewberry

Process Steps

Process Step 1

CC ID: 1146454
Description:

Data for the Puerto Rico and the US Virgin Islands project was acquired by Leading Edge Geomatics using a Riegl VQ-880-G II sensor. All delivered US Virgin Islands lidar data is referenced to:

Horizontal Datum-NAD83 (2011) epoch: 2010

Projection-UTM Zone 20 North

Horizontal Units-meters

Vertical Datum-NAD83 (2011)

Vertical Units-meters

Both green lidar data and NIR lidar data were acquired.

Leading Edge Geomatics acquired, calibrated, and performed refraction correction for the lidar data.

Process Date/Time: 2020-01-22 00:00:00
Process Contact: NGS Communications and Outreach Branch
Phone (Voice): (301) 713-3242
Email Address: ngs.infocenter@noaa.gov

Process Step 2

CC ID: 1146455
Description:

Dewberry received the calibrated green and NIR data and verified complete coverage. Relative accuracy of the green swaths compared to overlapping and adjacent green swaths as well as the relative accuracy of green swaths compared to overlapping and adjacent NIR swaths was verified through the use of Delta-Z (DZ) orthos created in GeoCue software. Intraswath relative accuracy was verified using Quick Terrain Modeler. Profiles of elevated planar features, such as roofs, were used to verify horizontal alignment between overlapping swaths. Dewberry then verified absolute vertical accuracy of the swath data prior to full-scale production.

Dewberry used algoritms in TerraScan to create the intial ground/submerged topography surface.

Dewberry used rasterized aggregate extents of refracted points to create automated 2-D breaklines with LAStools and ArcGIS. Light travels at different speeds in air versus water and its speed and direction of travel change when it enters the water column. The refraction correction process accounts for this difference by adjusting the depth (distance traveled) and horizontal position (change of angle/direction) of the lidar points acquired within water. These breaklines delineate areas where the refraction correction was applied to the lidar data by Riegl's automated refraction correction software based on the software's detection of water. Where the automated process missed discrete water bodies that did not contain valid bathymetry (submerged topography) data, breaklines were manually drawn and added to a separate feature class to ensure the correct classification of the point cloud.

Dewberry used the 2-D refraction extents and additional bathy features to classify the bathymetric bottom and ground points properly in TerraScan.

All lidar data was peer-reviewed. Dewberry's QAQC also included creating void polygons for use during review. All necessary edits were applied to the dataset. GeoCue software was used to update LAS header information, including all projection and coordinate reference system information. The final lidar data are in LAS format 1.4 and point data record format 6.

The final classificaton scheme is as follows:

0-Created, never classified

1-Unclassified

2-Ground

7-Noise

40-Bathymetric bottom

41-Water surface

42-Derived water surface

43-Submerged object, not otherwise specified

44-International Hydrograpic Organization (IHO) S-57 objects

45-No bottom found (bathymetric lidar point for which no detectable bottom return was received)

46-Bathymetric bottom temporal changes

All data was then verified by an Independent QC department within Dewberry. The independent QC was performed by separate analysts who did not perform manual classification or editing. The independent QC involved quantitative and qualitative reviews.

Process Date/Time: 2021-01-22 00:00:00

Process Step 3

CC ID: 1146456
Description:

The NOAA Office for Coastal Management (OCM) received files in laz format. The files contained lidar elevation and intensity measurements. The data were in UTM Zone 19 and UTM Zone 20 coordinates and ellipsoid elevations in meters. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. Converted from UTM Zone 19 and UTM Zone 20 to geographic coordinates 2. Sorted by gps time

Process Date/Time: 2021-10-08 00:00:00
Process Contact: Office for Coastal Management (OCM)

Child Items

Rubric scores updated every 15m

Rubric Score Type Title
Entity NOAA NGS Topobathy Lidar Class Scheme: U.S. Virgin Islands

Catalog Details

Catalog Item ID: 65631
GUID: gov.noaa.nmfs.inport:65631
Metadata Record Created By: Maryellen Sault
Metadata Record Created: 2021-10-21 12:19+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: NGS
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