2016 USGS Lidar: Maine QL2
Data Set (DS) | OCM Partners (OCMP)GUID: gov.noaa.nmfs.inport:49796 | Updated: August 9, 2022 | Published / External
Keywords
Theme Keywords
| Thesaurus | Keyword |
|---|---|
| ISO 19115 Topic Category |
elevation
|
| UNCONTROLLED | |
| None | Contours |
| None | Hydrology |
| None | Intensity Image |
Physical Location
| Organization: | Office for Coastal Management |
|---|---|
| City: | Charleston |
| State/Province: | SC |
Data Set Information
| Data Set Scope Code: | Data Set |
|---|---|
| Maintenance Frequency: | None Planned |
| Data Presentation Form: | Lidar point cloud |
| Distribution Liability: |
Any conclusions drawn from the analysis of this information are not the responsibility of Quantum Spatial, Inc., the U.S. Geological Survey (USGS), the Maine Office of GIS, NOAA, the NOAA Office for Coastal Management (OCM) or its partners. |
| Data Set Credit: | Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data. |
Support Roles
Data Steward
| Date Effective From: | 2017-06-14 |
|---|---|
| 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: | 2017-06-14 |
|---|---|
| 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: | 2017-06-14 |
|---|---|
| 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: | 2017-06-14 |
|---|---|
| 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: | -71.04629822983 | |
|---|---|---|
| E° Bound: | -69.15957708384 | |
| N° Bound: | 45.95653467626 | |
| S° Bound: | 44.00349372871 |
Extent Group 1 / Time Frame 1
| Time Frame Type: | Range |
|---|---|
| Start: | 2016-04-05 |
| End: | 2016-05-21 |
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=6264; |
| Data Access Constraints: |
No restrictions apply to this data. |
| Data Use Constraints: |
None. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use these data for critical applications without a full awareness of its limitations. Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data. |
Distribution Information
Distribution 1
| Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=6264 |
|---|---|
| Distributor: | |
| File Name: | Customized Download |
| Description: |
Create custom data files by choosing data area, product type, map projection, file format, datum, etc. |
Distribution 2
| Download URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/6264/index.html |
|---|---|
| Distributor: | |
| File Name: | Bulk Download |
| Description: |
Simple download of data files. |
URLs
URL 1
| URL: | https://coast.noaa.gov/dataviewer |
|---|---|
| URL Type: |
Online Resource
|
URL 2
| URL: | https://coast.noaa.gov/dataregistry |
|---|---|
| URL Type: |
Online Resource
|
URL 3
| URL: | https://coast.noaa.gov |
|---|---|
| URL Type: |
Online Resource
|
URL 4
| URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/6264/supplemental/me2016_usgs_me_ql2_m6264.kmz |
|---|---|
| Name: | Browse Graphic |
| URL Type: |
Browse Graphic
|
| File Resource Format: | kmz |
| Description: |
This graphic shows the lidar footprint for the 2016 USGS Maine QL2 lidar project. |
Activity Log
Activity Log 1
| Activity Date/Time: | 2017-05-23 |
|---|---|
| Description: |
Date that the source FGDC record was last modified. |
Activity Log 2
| Activity Date/Time: | 2017-11-14 |
|---|---|
| Description: |
Converted from FGDC Content Standards 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
| Activity Date/Time: | 2018-02-08 |
|---|---|
| Description: |
Partial upload of Positional Accuracy fields only. |
Activity Log 4
| Activity Date/Time: | 2018-03-13 |
|---|---|
| Description: |
Partial upload to move data access links to Distribution Info. |
Data Quality
| Vertical Positional Accuracy: |
The project specifications require that only Non-Vegetated Vertical Accuracy (NVA) be computed for raw lidar point cloud swath files. The required accuracy (ACCz) is: 19.6 cm at a 95% confidence level, derived according to NSSDA, i.e., based on RMSE of 10 cm in the "bare earth" and "urban" land cover classes. The NVA was tested with 116 of 118 checkpoints located in bare earth and urban (non-vegetated) areas. These check points were not used in the calibration or post processing of the lidar point cloud data. The checkpoints were distributed throughout the project area and were surveyed using GPS techniques. See survey report for additional survey methodologies. Elevations from the unclassified lidar surface were measured for the x,y location of each check point. Elevations interpolated from the lidar surface were then compared to the elevation values of the surveyed control points. AccuracyZ has been tested to meet 19.6 cm or better Non-Vegetated Vertical Accuracy at 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASRPS Guidelines. The project specifications require the accuracy (ACCz) of the derived DEM be calculated and reported in two ways: 1. The required NVA is: 19.6 cm at a 95% confidence level, derived according to NSSDA, i.e., based on RMSE of 10 cm in the "bare earth" and "urban" land cover classes. This is a required accuracy. The NVA was tested with 118 checkpoints located in bare earth and urban (non-vegetated) areas. 2. Vegetated Vertical Accuracy (VVA): VVA shall be reported for "forested", "brushland/trees", and "tall weeds/crops" land cover classes. The target VVA is: 29.4 cm at the 95th percentile, derived according to ASPRS Guidelines, Vertical Accuracy Reporting for Lidar Data, i.e., based on the 95th percentile error in all vegetated land cover classes combined. This is a target accuracy. The VVA was tested with 87 checkpoints located in forested, brushland/trees, and tall weeds/crops (vegetated) areas. The checkpoints were distributed throughout the project area and were surveyed using GPS techniques. See survey report for additional survey methodologies. AccuracyZ has been tested to meet 19.6 cm or better Non-Vegetated Vertical Accuracy at 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASRPS Guidelines.; Quantitative Value: 0.114 meters, Test that produced the value: Tested 0.114 meters NVA at a 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA). The NVA of the raw lidar point cloud swath files was calculated against TINs derived from the final calibrated and controlled swath data using 116 independent checkpoints located in Bare Earth and Urban land cover classes.; Quantitative Value: 0.113 meters, Test that produced the value: Tested 0.113 meters NVA at a 95% confidence level using RMSE(z) x 1.9600 as defined by the National Standards for Spatial Data Accuracy (NSSDA). The NVA of the DEM was calculated using 118 independent checkpoints located in the Bare Earth and Urban land cover categories.; Quantitative Value: 0.253 meters, Test that produced the value: Tested 0.253 meters VVA was calculated using 87 checkpoints located in the Forested, Brushland/Trees, and Tall Weeds/Crops land cover categories at the 95th percentile, derived according to ASPRS Guidelines, Vertical Accuracy Reporting for Lidar Data. Tested against the DEM. |
|---|---|
| Completeness Report: |
These raw LAS and LAS data files include all data points collected. No points have been removed or excluded. The raw point cloud is of good quality and data passes Non-Vegetated Vertical Accuracy specifications. Datasets contain complete coverage of tiles. A visual qualitative assessment was performed to ensure data completeness. There are no void areas or missing data. All files are inspected to ensure that they conform to the specified file naming conventions, all files load in their correct geographic position, all files conform to the project specifications for file standard and content. |
| Conceptual Consistency: |
Data covers the entire area specified for this project. |
Lineage
Process Steps
Process Step 1
| Description: |
Raw Data and Boresight Processing: 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 Quantum Spatial, Inc. proprietary and 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 7 cm RMSEz within individual swaths and less than or equal to 10 cm RMSEz or within swath overlap (between adjacent swaths). 5) The technicians ran a final vertical accuracy check of the boresighted flight lines against the surveyed check points after the z correction to ensure the requirement of NVA = 19.6 cm 95% Confidence Level (Required Accuracy) was met. |
|---|---|
| Process Date/Time: | 2016-01-01 00:00:00 |
Process Step 2
| Description: |
LAS Point Classification: The point classification is performed as described below. 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. All ground (ASPRS Class 2) lidar data inside of the Lake Pond and Double Line Drain hydro-flattened 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. All bridge decks were classified to Class 17. 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 using standard LAS overlap bit. 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. These processes were reviewed and accepted by USGS through numerous conference calls and pilot study areas. All data was manually reviewed and any remaining artifacts removed using functionality provided by TerraScan and TerraModeler. Global Mapper us used as a final check of the bare earth dataset. GeoCue was then used to create the deliverable industry-standard LAS files for both the All Point Cloud Data and the Bare Earth. Quantum Spatial, Inc. proprietary software was used to perform final statistical analysis of the classes in the LAS files, on a per tile level to verify final classification metrics and full LAS header information. |
|---|---|
| Process Date/Time: | 2016-01-01 00:00:00 |
Process Step 3
| Description: |
The NOAA Office for Coastal Management (OCM) received 6115 las files in las 1.4 format from the Maine Office of GIS. The files contained lidar intensity and elevation measurements for the project area in Maine. The data were in UTM Zone 19 coordinates and in NAVD88 elevations in meters. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. The LAStools software scripts lasinfo and lasvalidate were run on the las files to check for errors. 2. Internal OCM scripts were run to convert the files from UTM Zone 19 coordinates to geographic coordinates and to convert from NAVD88 elevations to ellipsoid elevations using Geoid12b. 3. Internal OCM scripts were run on the las files to assign the geokeys, to sort the data by gps time and zip the data to database and to http. |
|---|---|
| Process Date/Time: | 2017-05-19 00:00:00 |
Catalog Details
| Catalog Item ID: | 49796 |
|---|---|
| GUID: | gov.noaa.nmfs.inport:49796 |
| Metadata Record Created By: | Anne Ball |
| Metadata Record Created: | 2017-11-15 15:22+0000 |
| Metadata Record Last Modified By: | SysAdmin InPortAdmin |
| Metadata Record Last Modified: | 2022-08-09 17:11+0000 |
| Metadata Record Published: | 2022-03-16 |
| Owner Org: | OCMP |
| Metadata Publication Status: | Published Externally |
| Do Not Publish?: | N |
| Metadata Last Review Date: | 2022-03-16 |
| Metadata Review Frequency: | 1 Year |
| Metadata Next Review Date: | 2023-03-16 |
