Monroe County, WI LiDAR TASK ORDER

Metadata:


Identification_Information:
Citation:
Citation_Information:
Publication_Date: Unknown
Title:
Monroe County, WI LiDAR TASK ORDER
Geospatial_Data_Presentation_Form: remote-sensing image
Description:
Abstract:
This task order is for planning, acquisition, processing, and derivative products of lidar data to be collected for Monroe County, Wisconsin. Specifications listed below are based on the US Geological Survey National Geospatial Program Base Lidar Specification, Version 13.

Monroe County, Wisconsin has a requirement for LiDAR covering the entire county to be collected at a nominal pulse spacing (NPS) of 1.2 meters.
Purpose:
The Monroe County, WI LiDAR project is to provide high accuracy bare-earth processed LiDAR data suitable for Monroe County, WI.

The project consisted of acquisition, post-processing, and classification of LiDAR data.  The classified bare-earth data achieved the following:  Vertical accuracy was to achieve a RMSE Z of 15cm (95% confidence level of less than 30cm) or better in the "Open Terrain" land cover category.

Accuracy statement is based on the area of moderate to flat terrain. Diminished accuracies are to be expected in areas of dense vegetation. The accuracy of the LiDAR data as tested met the vertical accuracy or better, however, derived products may be less accurate in areas of dense vegetation due to a lesser number of points defining the bare-earth in these areas.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20100323
Currentness_Reference:
ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: unknown
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -90.979
East_Bounding_Coordinate: -90.312
North_Bounding_Coordinate: 44.161
South_Bounding_Coordinate: 43.725
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Monroe County
Theme_Keyword: Light Detection and Ranging
Theme_Keyword: LiDAR
Theme_Keyword: Bare Earth
Theme_Keyword: Point Cloud
Theme_Keyword: DEM
Theme_Keyword: breaklines
Theme_Keyword: Intensity
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: US
Place_Keyword: State
Place_Keyword: Wisconsin
Access_Constraints: There was a flight restriction during the original flight in March 2010 for an area covering the Fort McCoy Army Base in the northwest part of Monroe County. This area was not flown until authorization was cleared and this part of Monroe was flown the end of November 2010.
Use_Constraints:
None.
Data_Set_Credit:
Ayres Associates
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Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The vertical accuracy of the Classified Bare Earth files for the Monroe County project achieved a RMSE of 0.226 feet. 8 control points were used in this evaluation.
Logical_Consistency_Report:
Consistency was maintained throughout the dataset.
Completeness_Report:
The files cover the full extent of the contract.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The dataset was developed to generate contours meeting the National Map Accuracy Standards for the scale 1:600.  Test points will fall on the correct side of the contours developed from this DTM for ninety percent of all points.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Based on tests conducted by staff from Monroe County:
Survey grade elevations were taken in the project area in five different types of cover. These elevations were compared with the LiDAR terrain elevation. RMSE results: Overall: 0.226
Lineage:
Process_Step:
Process_Description:
The LiDAR data was captured using an Aero Commander 500 Shrike and the Cessna 320 Skynight (twin-piston), fixed wing aircraft equipped with a LiDAR system.  The LiDAR system includes a differential GPS unit and inertial measurement system to provide superior accuracy.

Acquisition parameters:  
1. Scanner - ALTM Gemini LiDAR  
2. Flight Height - 1700 meters above mean terrain
3. Swath Width - 32 degrees
4. Sidelap - 50%
5. Nominal Post Spacing - 1.2m

GPS and IMU processing parameters:  
1. Processing Programs and version - Applanix POSPac, version 4.4  
2. Maximum baseline length - Not greater than 50km.
3. Number of base stations during LiDAR collection - A minimum of 2.  
4. Max separation between base stations during LiDAR collection - 0.10m  
5. IMU processing monitored for consistency and smoothness - Yes.

Point Cloud Processing:  
1. Program and version - Optech's Dashmap 5.20
2. Horizontal Datum - NAD83  
3. Horizontal Coordinates - WISCRS Monroe County, in US Survey Feet.
4. Vertical Datum - NAVD88  
5. Geoid Model used to reduce satellite derived elevations to orthometric heights - NGS Geoid09.

LiDAR Processing:  
1. Processing Programs and versions - TerraSolid TerraScan (version 011.015), TerraModeler (version 011.005 and TerraMatch (version 011.011) and Intergraph MicroStation (version.08.05.02.70).
2. Point Cloud data is imported to TerraScan in a Microstation V8 (V) CAD environment in a PLSS tiling scheme.
3. Analyze the data for overall completeness and consistency.  This is to ensure that there are no voids in the data collection.  
4. 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).  
5. Orientation corrections (i.e. Calibration corrections) are then applied (if needed) to the entire dataset.  
6. 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.  
7. Quality Assurance and Quality Control (QA/QC) points were captured in 'open terrian' 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 to the LiDAR data.  A final OCR was performed with a resulting RMSE of 0.226 ft for the project.  
8. Once the automatic processing and testing of LiDAR is complete, the generated bare-earth surface data is reviewed to ensure that proper classification was achieved as part of a Quality Control process. 
9. Final deliverables are generated and output to a client specified PLSS tiling scheme.
Process_Date: Unknown
Process_Step:
Process_Description:
Prepared FGDC-compliant metadata.
Cloud_Cover: Unknown
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Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Point
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Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 1.0000434122
Longitude_of_Central_Meridian: -90.64166666666668
Latitude_of_Projection_Origin: 44.00007392861111
False_Easting: 671000.000
False_Northing: 400012.278
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.01
Ordinate_Resolution: 0.01
Planar_Distance_Units: survey feet
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
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: survey feet
Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates
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Metadata_Reference_Information:
Metadata_Date: 20111130
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Ayres Associates
Contact_Address:
Address_Type: mailing and physical address
Address:
1802 Pankratz Street
City: Madison
State_or_Province: Wisconsin
Postal_Code: 53704
Country: US
Contact_Voice_Telephone: 608-443-1200
Contact_Facsimile_Telephone: 608-443-1250
Hours_of_Service: Monday through Friday 8:00 AM to 5:00 PM (Central Time)
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