Short Citation:
Office for Coastal Management, 2021: 2013 NOAA Topographic Lidar: U.S. Virgin Islands (St. Croix, St. John, St. Thomas), https://www.fisheries.noaa.gov/inport/item/48219.

Item Identification

Title: 2013 NOAA Topographic Lidar: U.S. Virgin Islands (St. Croix, St. John, St. Thomas)
Short Name: usvi2013_stc_stj_stt_m3669_metadata
Status: Completed
Publication Date: 2014-08-18
Abstract:

The United States Virgin Islands Topographic LiDAR project collected topographic elevation point data derived from multiple return light detection and ranging (LiDAR) measurements on the islands of St. Thomas, St. John, St. Croix and numerous smaller islands and islets in the United States Virgin Islands. The islands of St. Thomas and St. John were acquired between November 9, 2013 and November 19, 2013. The island of St. Croix was acquired between November 27, 2013 and December 10, 2013. The entire area was comprised of 88 planned flight lines and approximately 1669 flight line kilometers. LiDAR was collected at an average of 0.7 meter point spacing for all acquired project areas. The classification classes as available from the NOAA Digital Coast are: 1 (Unclassified), 2 (Bare-earth ground), 7 (Noise), 9 (Water), 10 (Ignored Ground, points close to breakline features), 16 (Overlap Water), 17 (Overlap Unclassified), 18 (Overlap Bare-earth ground). Hydro flattened breaklines and Digital Elevation Models (DEMs) are also available for download. Please see the Supplemental Information field below for links to these data sets.

Original contact information:

Contact Org: NOAA Office for Coastal Management

Phone: 843-740-1202

Email: coastal.info@noaa.gov

Purpose:

The purpose of the data is for use in coastal management decision making, including applications such as flood plain mapping and water rights management.

Notes:

10242

Supplemental Information:

The Post-Flight Aerial Acquisition and Calibration Report for this data set may be viewed at: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/supplemental/usvi2013_stc_stj_stt_m3669_post_flight_report.pdf The Quality Assurance Review Report for this data set may be viewed at: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/supplemental/usvi2013_stc_stj_stt_m3669_qa_report.pdf The Check Point Survey Report may be viewed at: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/supplemental/usvi2013_stc_stj_stt_m3669_chk_pnt_report.pdf

A footprint of this data set may be viewed in Google Earth at:

https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/supplemental/usvi2013_stc_stj_stt_m3669.kmz The hydrologically flattened breaklines may be accessed here:

https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/breaklines/

The hydrologically flattened 1 m raster bare earth DEMs may be accessed here:

https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/dems/

Keywords

Theme Keywords

Thesaurus Keyword
CoRIS Theme Thesaurus EARTH SCIENCE > Land Surface > Topography > Terrain Elevation
Global Change Master Directory (GCMD) Science Keywords Earth Science > Land Surface > Topography > Terrain Elevation > Topographical Relief Maps
Global Change Master Directory (GCMD) Science Keywords Earth Science > Oceans > Bathymetry/Seafloor Topography > Seafloor Topography
Global Change Master Directory (GCMD) Science Keywords Earth Science > Oceans > Coastal Processes > Coastal Elevation
ISO 19115 Topic Category elevation
None Bathymetry/Topography
None Breaklines
None DEM
None elevation
None LiDAR
None Model
None Point Cloud Data
None Raster
None Remote Sensing

Spatial Keywords

Thesaurus Keyword
CoRIS Place Thesaurus COUNTRY/TERRITORY > United States of America > U. S. Virgin Islands > U. S. Virgin Islands > U. S. Virgin Islands (17N064W0000)
CoRIS Place Thesaurus OCEAN BASIN > Atlantic Ocean > Caribbean Sea > Virgin Islands > Lesser Antilles > U. S. Virgin Islands (17N064W0000)
Global Change Master Directory (GCMD) Location Keywords Ocean > Atlantic Ocean > North Atlantic Ocean > Caribbean Sea > Virgin Islands
None Charlotte Amalie
None Saint Croix
None Saint John
None Saint Thomas
None United States
None United States Virgin Islands (USVI)

Physical Location

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

Data Set Information

Data Set Scope Code: Data Set
Maintenance Frequency: Unknown
Data Presentation Form: LAS Files
Distribution Liability:

Any conclusions drawn from the analysis of this information are not the responsibility of the National Oceanic and Atmospheric Administration (NOAA), the National Ocean Service (NOS), the Office for Coastal Management (OCM) or its partners.

Support Roles

Data Steward

CC ID: 625352
Date Effective From: 2014-08-18
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: 625354
Date Effective From: 2014-08-18
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: 625355
Date Effective From: 2014-08-18
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: 625353
Date Effective From: 2014-08-18
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: 625358
W° Bound: -65.093469
E° Bound: -64.561957
N° Bound: 18.423828
S° Bound: 17.670388

Extent Group 1 / Time Frame 1

CC ID: 625357
Time Frame Type: Range
Start: 2013-11-09
End: 2013-12-10

Spatial Information

Spatial Representation

Representations Used

Vector: Yes

Access Information

Security Class: Unclassified
Data Access Procedure:

This data can be obtained on-line at the following URL:

https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=3669

This data set is dynamically generated based on user-specified parameters.;

Data Access Constraints:

None

Data Use Constraints:

None, however, users should be aware that temporal changes may have occurred since this data set was collected and that some parts of the data may no longer represent actual surface conditions. Users should not use the data for critical applications without a full awareness of its limitations.

Distribution Information

Distribution 1

CC ID: 744041
Download URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=3669
Distributor:
File Name: Customized Download
Description:

Create custom data files by choosing data area, product type, map projection, file format, datum, etc.

Distribution 2

CC ID: 744042
Download URL: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669
Distributor:
File Name: Bulk Download
Description:

Simple download of data files.

URLs

URL 1

CC ID: 744044
URL: https://coast.noaa.gov/dataviewer
URL Type:
Online Resource

URL 2

CC ID: 744045
URL: https://coast.noaa.gov
URL Type:
Online Resource

URL 3

CC ID: 744046
URL: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/supplemental/usvi2013_stc_stj_stt_m3669.kmz
Name: Browse Graphic
URL Type:
Browse Graphic
File Resource Format: kmz
Description:

This graphic shows the lidar coverage for this data set.

Activity Log

Activity Log 1

CC ID: 625383
Activity Date/Time: 2017-05-04
Description:

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 625382
Activity Date/Time: 2017-11-14
Description:

Converted from FGDC Content Standard for Digital Geospatial Metadata (version FGDC-STD-001-1998) using 'fgdc_to_inport_xml.pl' script. Contact Tyler Christensen (NOS) for details.

Activity Log 3

CC ID: 717991
Activity Date/Time: 2018-02-08
Description:

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 744043
Activity Date/Time: 2018-03-13
Description:

Partial upload to move data access links to Distribution Info.

Data Quality

Accuracy:

The project area requires LiDAR to be collected on average of 0.7 meter point spacing or better and vertical accuracy of 9.25 centimeters RMSE or better to support 1' contour generation when combined with breaklines.

Horizontal Positional Accuracy:

The LiDAR data was compiled to meet a 1 meter horizontal accuracy. The calibration of the LiDAR sensor itself and the calibration process of the data produced by this sensor ensure that this accuracy is met.; Quantitative Value: 1.0 meters, Test that produced the value: Value stated in meters

Vertical Positional Accuracy:

NOAA OCM conducted the vertical accuracy assessment for this data set. Eighty ground control points were collected on all three islands. The following are the number of points collected per island: St. Croix (31), St. John (19), St. Thomas (30). The accuracy specification called for a 9.25 cm Root Mean Square Error (RMSE) for all the islands. St. John and St. Thomas met this specification, however, St. Croix did not. The RMSE values for each island are as follows: St. Croix (14 cm), St. John (7 cm), St. Thomas (8 cm). The all islands RMSE value is 11 cm. The Quality Assurance Review Report may be viewed at: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/supplemental/usvi2013_stc_stj_stt_m3669_qa_report.pdf The Check Point Survey Report may be viewed at: https://coast.noaa.gov/htdata/lidar2_z/geoid12b/data/3669/supplemental/usvi2013_stc_stj_stt_m3669_chk_pnt_report.pdf

; Quantitative Value: 0.11 meters, Test that produced the value: RMSE in meters of classified LiDAR

Completeness Report:

Datasets contain complete coverage of tiles.

Conceptual Consistency:

Classified LAS were tested by Photo Science, Inc. for vertical accuracy. All data are seamless from one tile to the next, no gaps or no data areas.

Lineage

Sources

LiDAR

CC ID: 625341
Contact Name: Photo Science, Inc.
Publish Date: 2014-01-01
Extent Type: Range
Extent Start Date/Time: 2013-11-09
Extent End Date/Time: 2013-12-10
Source Contribution:

LiDAR points were used to produce the deliverables. | Source Geospatial Form: digital data | Type of Source Media: Hard Drive

Process Steps

Process Step 1

CC ID: 625342
Description:

Applanix + POSPac Mobile Mapping Suite software was used for post-processing of airborne GPS and inertial data (IMU), which is critical to the positioning and orientation of the LiDAR sensor during all flights. POSPac combines aircraft raw trajectory data with stationary GPS base station data yielding a Smoothed Best Estimate Trajectory (SBET) necessary for additional post processing software to develop the resulting geo-referenced point cloud from the LiDAR missions.

During the sensor trajectory processing (combining GPS and IMU datasets) certain statistical graphs and tables are generated within the Applanix POSPac processing environment which are commonly used as indicators of processing stability and accuracy. This data for analysis include: Max horizontal / vertical GPS variance, separation plot, altitude plot, PDOP plot, base station baseline length, processing mode, number of satellite vehicles, and mission trajectory.

The generated point cloud is the mathematical three dimensional composite of all returns from all laser pulses as determined from the aerial mission. Point clouds were created using the Leica ALS Post Processor software. Laser point data are imported into TerraScan and a manual calibration is performed to assess the system offsets for pitch, roll, heading and scale. At this point this data is ready for analysis, classification, and filtering to generate a bare earth surface model in which the above-ground features are removed from the data set. GeoCue distributive processing software was used in the creation of some files needed in downstream processing, as well as in the tiling of the dataset into more manageable file sizes. TerraScan and TerraModeler software packages were then used for the automated data classification, manual cleanup, and bare earth generation. Project specific macros were developed to classify the ground and remove side overlap between parallel flight lines.

The classes used in the dataset are as follows and have the following descriptions:

Class 1 (Processed, but Unclassified) These points would be the catch all for points that do not fit any of the other deliverable classes. This would cover things like vegetation, buildings, cars, bridges, etc.

Class 2 (Bare earth ground) This is the bare earth surface

Class 7 (Noise) Low or high points, manually and/or automatically identified above or below the surface that could be noise points in point cloud.

Class 9 (Water) Points found inside of inland lake/ponds, rivers or points on the ocean side of any shoreline feature.

Class 10 (Ignored Ground) Points found to be close to breakline features. Points are typically moved to this class from Class 2.

This class is ignored during the DEM creation.

Class 17 (Overlap Default (Unclassified)) Points found in the overlap between flight lines. These points are created through automated processing methods and are not cleaned up during manual classification.

Class 18 (Overlap Bare earth ground) Points found in the overlap between flight lines. These points are created through automated processing, matching the specifications determined during the automated process, that are close to the Class 2 dataset

(when analyzed using height from ground analysis)

Class 25 (Overlap Water) Points found in the overlap between flight lines that are located inside hydro features. These points are created through automated processing methods and are not cleaned up during manual classification.

Process Date/Time: 2014-01-01 00:00:00
Source: LiDAR

Process Step 2

CC ID: 625343
Description:

All overlap data was processed through automated functionality provided by TerraScan to classify the overlapping flight line data to approved classes by USGS. The overlap data was classified to Class 17 (Overlap Default) and Class 18 (Overlap Ground). These classes were created through automated processes only and were not verified for classification accuracy. Due to software limitations within TerraScan, these classes were used to trip the withheld bit within various software packages.

The bare earth surface is then manually reviewed to ensure correct classification on the Class 2 (Ground) points. After the bare earth surface is finalized; it is then used to generate all hydro-breaklines through heads-up digitization.

Class 2 LIDAR was used to create a bare earth surface model. The surface model and LAS intensity were then used to heads-up digitize 2D breaklines of inland streams and rivers as well as the ocean shoreline. Inland Ponds and Lakes of 2 acres or greater were also collected.

All ground (ASPRS Class 2) LiDAR data inside of the collected hydro flattening breaklines were then classified to water (ASPRS Class 9) using TerraScan macro functionality. A buffer of 1 meter was also used around each hydro-flattened feature to classify these ground (ASPRS Class 2) points to Ignored ground (ASPRS Class 10). All Lake Pond Island and Double Line Drain Island features were checked to ensure that the ground (ASPRS Class 2) points were reclassified to the correct classification after the automated classification was completed.

LAS data was then run through additional macros to ensure deliverable classification levels matching LAS ASPRS Classification structure. GeoCue functionality was used to ensure correct LAS Version. In house software was used as a final QA/QC check to provide LAS Analysis of the delivered tiles.

Process Date/Time: 2014-01-01 00:00:00
Source: LiDAR

Process Step 3

CC ID: 625344
Description:

The lidar files were received by the NOAA Office for Coastal Management for incorporation into the NOAA Digital Coast. The data consisted of 358 lidar files. The data were in LAS format 1.2 and were in UTM, Zone 20, NAD83, meters coordinates. The data were in Virgin Islands Vertical Datum (VIVD09), meters vertical units. The classifications of the data were: 1 (Unclassified), 2 (Ground), 7 (Noise), 9 (Water), 10 (Ignored Ground, breakline proximity), 17 (Overlap Unclassified), 18 (Overlap Ground), 25 (Overlap Water). For Digital Coast data storage and provisioning purposes, the NOAA OCM performed the following processing: 1. The data were reviewed for any elevation outliers. 2. The data were converted from UTM, Zone 20 coordinates to geographic coordinates. 3. The data were converted from VIVD09 elevations to ellipsoid elevations using Geoid12a. 4. The points that were classified as 25 (Overlap Water) were reclassified to 16 (Overlap Water). 5. The global encoding bit in the las file headers was changed from 0 to 1. 6. The data were converted from las to laz format.

Process Date/Time: 2014-05-13 00:00:00

Catalog Details

Catalog Item ID: 48219
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-14 14:20+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2019-07-02 15:17+0000
Metadata Record Published: 2018-03-13
Owner Org: OCM
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Next Review Date: 2019-03-14