Juneau, Alaska vicinity LiDAR TASK ORDER

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: AeroMetric, Inc.

Publication_Date: 20121211

Title: Juneau, Alaska vicinity LiDAR TASK ORDER

Geospatial_Data_Presentation_Form:

tabular digital data
vector digital data

Publication_Information:

Publication_Place: Sheboygan, WI

Publisher: AeroMetric

Description:

Abstract:

This task order is for planning, acquisition, processing, and derivative products of LiDAR data to be collected for Juneau, Alaska. LiDAR data, and derivative products produced in compliance with this task order are part of the data to be obtained under Contract number G10PC00025, Order number G12PD00481. Specifications listed below are based on the U.S. Geological Survey National Geospatial Program Base LiDAR Specification, Version 13.

Purpose:

USGS has a requirement for LiDAR data in Juneau, Alaska and vicinity. Data is to be collected at a nominal pulse spacing (NPS) of 1.0 meters or less. The Juneau, Alaska LiDAR Acquisition project is to provide high accuracy bare-earth processed LiDAR data suitable for the project area. The project consisted of acquisition, post-processing, classification of LiDAR data, and creation of final deliverable products. All areas shall be collected at a nominal pulse spacing (NPS) of 1.0 meters or less based on UTM 8, related to the North American Datum of 1983. Vertical accuracy was to achieve a RMSE Z of 12.5 cm (95% confidence level of less than 24.5 cm) or better in the "Open Terrain" land cover category for all areas. Accuracy statement is based on areas of moderate to flat terrain. Diminished accuracies are to be expected in areas in dense vegetation. The accuracy of the LiDAR data as tested met or exceeded the vertical accuracy requirements, however, derived products may be less accurate in areas of dense vegetation due to a lesser number of points defining the bare-earth in such areas.

Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 20120425

Currentness_Reference: ground condition

Status:

Progress: Complete

Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -134.854

East_Bounding_Coordinate: -134.255

North_Bounding_Coordinate: 58.55200

South_Bounding_Coordinate: 58.21200

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: Juneau, Alaska

Theme_Keyword: Light Detection and Ranging

Theme_Keyword: LiDAR

Theme_Keyword: Breaklines

Theme_Keyword: Shapefiles

Theme_Keyword: Survey Control

Theme_Keyword: DEM

Theme_Keyword: Lift

Theme_Keyword: LAS

Theme_Keyword: Swath

Place:

Place_Keyword_Thesaurus: None

Place_Keyword: US

Place_Keyword: State

Place_Keyword: Juneau

Place_Keyword: Alaska

Place_Keyword: AK

Access_Constraints: None.

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 this data may no longer represent actual surface conditions.
Areas of high elevation included in the project may have snowpack present throughout the year.
Users should not use this data for critical applications without a full awareness of its limitations.
Acknowledgment of the U.S. Geological Survey would be appreciated for products derived from these data.

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Mike Duncan

Contact_Organization: USGS

Contact_Position: NGTOC

Contact_Address:

Address_Type: mailing and physical address

Address: 1400 Independence Road

City: Rolla

State_or_Province: MO

Postal_Code: 65401

Country: USA

Contact_Voice_Telephone: 573-308-3799

Contact_TDD/TTY_Telephone: unknown

Contact_Facsimile_Telephone: 573-308-3810

Contact_Electronic_Mail_Address: jduncan@usgs.gov

Hours_of_Service: unknown

Contact_Instructions: none

Data_Set_Credit: AeroMetric, Inc.

Native_Data_Set_Environment:

1. Scanner - Optech Gemini Serial 03SEN145
2. Processing Programs and versions - Applanix - POSGPS and POSProc, versions 4.4, MMS version 5.2
3. Program and version - Optech ASDA
4. Processing Programs and versions - TerraSolid TerraScan (version 012.016), TerraModeler (version 012.008) and TerraMatch (version 012.009), Intergraph MicroStation (version 08.05.02.55), and GeoCue (version 2011.1.20.4).
5. Viewing Program - GlobalMapper V13.00

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The vertical accuracy assessment of the data has a project requirement to achieve a Fundamental Vertical Accuracy (FVA) of 24.5 cm 95% confidence level, a requirement to achieve a Consolidated Vertical Accuracy (CVA) of 36.3 cm 95th Percentile and a target value for Supplemental Vertical Accuracies (SVA) of 36.3 cm 95th Percentile.
The FVA of the LAS Swath Data achieved 20.9 cm at a 95% confidence level with an RMSE of 10.7 cm utilizing (29) ground survey check points in the evaluation.
The SVA results in Short Grass achieved 15.6 cm at the 95th Percentile where (30) checkpoints were used in the evaluation.
The SVA results Brush achieved 32.2 cm at the 95th Percentile where (80) checkpoints were used in the evaluation.
The SVA results Trees achieved 25.2 cm at the 95th Percentile where (92) checkpoints were used in the evaluation.
The SVA results Urban achieved 13.8 cm at the 95th Percentile where (252) checkpoints were used in the evaluation.
The CVA results for all Land Cover Classes combined achieved 21.8 cm at the 95th Percentile where (483) checkpoints were evaluated.
An additional (20) ground control check points are held in reserve and supplied to the client.

Logical_Consistency_Report: None

Completeness_Report: Complete

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

Area data products collected with the Optech Gemini were acquired at or below 1500 meters above mean terrain (AMT) and have a horizontal accuracy of 0.30 meters (per manufacturers system specifications), with a nominal point spacing of 1.0 meters.

Lineage:

Process_Step:

Process_Description:

The LiDAR data was captured using AeroMetric's twin-engine fixed wing aircraft equipped with an Optech LiDAR system. The LiDAR systems includes a differential GPS unit and inertial measurement system to provide superior accuracy.

Acquisition parameters:
1. Flight Height - 1500 meters or lower above mean terrain
2. Swath Width - 28 degrees
3. Sidelap - 55%
4. Nominal Post Spacing - 1.0 meters

GPS and IMU processing parameters
1. Maximum baseline length - Not greater than 100 kilometers.
2. Number of base stations during LiDAR collection - A minimum of 1.
3. Maximum positional RMS of trajectory during LiDAR collection - 0.10 meters
4. IMU processing monitored for consistency and smoothness - Yes.

Point Cloud Processing:
1. Horizontal Datum - NAD83
2. Horizontal Coordinates - Universal Transverse Mercator, Zone 8, in meters.
3. Vertical Datum - NAVD88
4. Geoid Model used to reduce satellite derived elevations to orthometric heights - NGS Geoid09.

LiDAR Processing:
1. Point Cloud data is imported to TerraScan in a Microstation V8 (V) CAD environment on a specified 1500 meter by 1500 meter tiling scheme.
2. Analyze the data for overall completeness and consistency. This is to ensure that there are no voids in the data collection.
3. Inspect for calibration errors in the dataset using the TerraMatch software. This is accomplished by sampling the data collected across all flight lines and classify the individual lines to ground. The software will use the ground-classified lines to compute corrections (Heading, Pitch, Roll, and Scale).
4. Orientation corrections (i.e. Calibration corrections) are then applied (if needed) to the entire dataset.
5. Automatic ground classification is performed using algorithms with customized parameters to best fit the project area. Several areas of varying relief and planimetric features were inspected to verify the final ground surface.
6. AeroMetric, Inc. provided Quality Assurance and Quality Control (QA/QC) data for this project. AeroMetric captured QA/QC points in 'open terrain' land cover category that were used to test the accuracy of the LiDAR ground surface. TerraScan's Output Control Report (OCR) was used to compare the QA/QC data to the LiDAR data. This routine searches the LiDAR dataset by X and Y coordinate, finds the closest LiDAR point and compares the vertical (Z) values to the known data collected in the field. Based on the QA/QC data, a bias adjustment was determined, and the results were applied (if necessary) to the LiDAR data. A final OCR was performed with a resulting RMSE of 10.7 for the project.
7. After the LiDAR data is finalized for vertical placement, a macro is run via TerraScan to output a dataset generated on a per swath basis as part of the final deliverables. All points of the swath are reclassified to class 0 during this step.
8. Each tile is reviewed for accuracy and consistency of the macro ground classification. During this phase, MicroStation is used to generate line work representing water bodies and rivers. Separate line work is also placed in instances where overpasses have blocked enough valid ground returns or water gave too few ground returns to reasonably portray the ground surface. A proprietary in-house software program is then run to drape the river line work in a flowing fashion. Contours are generated on the river breaklines to review monotonicity of the draped line work.
9. Once the automatic processing and the testing of LiDAR is complete, AeroMetric meticulously reviews the generated bare-earth surface data to ensure that proper classification was achieved as part of a Quality Control process.
10. Final deliverables are generated and output to a client specified 1500 meter by 1500 meter tiling scheme.

Process_Date: 20121001

Cloud_Cover: Unknown

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Point

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name: Universal Transverse Mercator

Universal_Transverse_Mercator:

UTM_Zone_Number: 8

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.9996

Longitude_of_Central_Meridian: -135

Latitude_of_Projection_Origin: 0

False_Easting: 500000

False_Northing: 0

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Coordinate_Representation:

Abscissa_Resolution: 0.01

Ordinate_Resolution: 0.01

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geoid 09

Semi-major_Axis: 6378137

Denominator_of_Flattening_Ratio: 298.257222101

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988

Altitude_Resolution: 0.01

Altitude_Distance_Units: meters

Altitude_Encoding_Method:

Explicit elevation coordinate included with horizontal coordinates

Metadata_Reference_Information:

Metadata_Date: 20121025

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: AeroMetric, Inc.

Contact_Address:

Address_Type: Mailing and physical address

Address: 4020 Technology Parkway

City: Sheboygan

State_or_Province: WI

Postal_Code: 53083-6049

Country: US

Contact_Voice_Telephone: 1-920-457-3631

Contact_Facsimile_Telephone: 1-920-457-0410

Contact_Electronic_Mail_Address: cguy@aerometric.com

Hours_of_Service: Monday through Friday 8:00 AM to 5:00 PM (Central Time)

Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998