Bare Earth Raster Grids for Lewis County 2006

Metadata also available as

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: Puget Sound LiDAR Consortium
Originator: Watershed Sciences, Inc.
Publication_Date: 2006
Title: be3_46122_e6
Geospatial_Data_Presentation_Form: raster digital data
Online_Linkage:
\\lidar\data\Drive2\pslc2006\lewis06\be_e00_3ft\e00_original\be3_46122_e6
Description:
Abstract:
The dataset covers portions of Lewis County in Southwestern Washington State.
The bare earth digital elevation models (DEM) represent the earth's surface with all vegetation and human-made structures removed. The bare earth DEMs were derived from LiDAR data using TIN processing of the ground point returns. The DEM grid cell size is three feet. The elevation units are in feet.
Watershed Sciences, Inc. collected the LiDAR and created this data set for the Puget Sound LiDAR Consortium.
Purpose:
Provide high resolution terrain elevation and land cover elevation data.
Supplemental_Information: This data is assembled into 7.5-minute USGS quadrangles.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 03/19/2006
Ending_Date: 03/29/2006
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -122.752770
East_Bounding_Coordinate: -122.669657
North_Bounding_Coordinate: 46.626402
South_Bounding_Coordinate: 46.586776
Keywords:
Theme:
Theme_Keyword_Thesaurus:
REQUIRED: Reference to a formally registered thesaurus or a similar authoritative source of theme keywords.
Theme_Keyword: LiDAR
Theme_Keyword: Light Detection and Ranging
Theme_Keyword: DEM
Theme_Keyword: digital terrain model
Theme_Keyword: puget sound lidar consortium
Theme_Keyword: elevation data
Theme_Keyword: topography
Theme_Keyword: bare earth
Theme_Keyword: high-resolution
Theme_Keyword: bare earth
Theme_Keyword: bare ground
Theme_Keyword: DTM
Place:
Place_Keyword: Washington
Place_Keyword: Washington State
Place_Keyword: Lewis County
Place_Keyword: Pacific Northwest
Place_Keyword: Western Washington
Access_Constraints: None.
Use_Constraints:
In some areas of heavy vegetation or forest cover, there may be relatively few ground points in the LiDAR data. TINing the points produces large triangles and hence the elevations may be less accurate within such areas.
Elevation values for open water surfaces are not valid elevation values because few LiDAR points are returned from water surfaces. Triangles were created across water surfaces by interpolating from the nearest land points.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Puget Sound LiDAR Consortium / Puget Sound Regional Council
Contact_Address:
Address: 1011 Western Avenue, Suite 500
City: Seattle
State_or_Province: WA
Postal_Code: 98104-1035
Country: USA
Contact_Voice_Telephone: 206-464-5325
Data_Set_Credit:
Puget Sound LiDAR Consortium (PSLC). The PSLC is supported by the Puget Sound Regional Council, the National Aeronautical and Space Administration (NASA), the United States Geological Survey (USGS) and partners in the local, state, and tirbal government. For more information, visit <http://pugetsoundlidar.ess.washington.edu/>
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.3.1.3500
Data_Quality_Information:
Logical_Consistency_Report:
LiDAR flight lines have been examined to ensure that there was at least 50% sidelap, there are no gaps between flightlines, and overlapping flightlines have consistent elevation values.
Shaded relief images have been visually inspected for data errors such as pits, border artifacts, gaps, and shifting. The data was examined at a 1:3500 scale.
Completeness_Report:
LiDAR data has been collected and processed for all areas within the project study area.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: 1/3000th AGL
Horizontal_Positional_Accuracy_Explanation: See LiDAR data report.
Vertical_Positional_Accuracy:
Quantitative_Vertical_Positional_Accuracy_Assessment:
Vertical_Positional_Accuracy_Value: RMSE = 0.21 feet
Vertical_Positional_Accuracy_Explanation:
The Root Mean Square Error (RMSE) of the data set is 0.21 feet. Accuracy was assessed using 1,522 ground survey (real time kinematic) points. See LiDAR data report.
Lineage:
Process_Step:
Process_Description:
Acquisition.
The LiDAR data was collected during March 2006. This was a leaf-off condition. An Optech 3100 LiDAR system was mounted in a fixed-wing aircraft and flown 1,200 meters above ground level (AGL). A pulse repetition frequency (PRF) of 71 kHz with at least 100% overlap (minimum 50% side-lap) was used. Greater than 8 points per square meter and near nadir scan angles were used to increase penetration of vegetation to ground surfaces. Spot spacing was less than or equal to 34 centimeters. Ground level GPS and aircraft IMU were collected during the flight.
Process_Step:
Process_Description:
Processing.
1. Flight lines and data were reviewed to ensure complete coverage of the study area and positional accuracy of the laser points. 2. Laser point return coordinates were computed using the REALM survey suite and PosPac based on independent data from the LiDAR system, IMU, and aircraft. 3. The raw LiDAR file was assembled into flight lines per return with each point having an associated x, y, and z coordinate. 4. Visual inspection of swath to swath laser point consistencies within the study area were used to perform manual refinements of system alignment. 5. Custom algorithms were designed to evaluate points between adjacent flight lines. Automated system alignment was computed based upon randomly selected swath to swath accuracy measurements that consider elevation, slope, and intensities. Specifically, refinement in the combination of system pitch, roll and yaw offset parameters optimize internal consistency. 6. Noise (e.g., pits and birds) was filtered using REALM software tools based on known elevation ranges and included the removal of any cycle slips. 7. Using TerraScan and Microstation, ground classifications utilized custom settings appropriate to the study area. 8. The corrected and filtered return points were compared to the RTK ground survey points collected to verify the vertical and horizontal accuracies. 9. Points were broken into processing bins and output areas and output as laser points, TINed and GRIDed surfaces. Bare earth DEMs meet PSLC specifications.
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 4627
Column_Count: 6836
Vertical_Count: 1
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Lambert Conformal Conic
Lambert_Conformal_Conic:
Standard_Parallel: 45.833333
Standard_Parallel: 47.333333
Longitude_of_Central_Meridian: -120.500000
Latitude_of_Projection_Origin: 45.333333
False_Easting: 1640416.666667
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: row and column
Coordinate_Representation:
Abscissa_Resolution: 3.000000
Ordinate_Resolution: 3.000000
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: 298.257222
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: All
Attribute:
Attribute_Label: ObjectID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Value
Attribute:
Attribute_Label: Count
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Puget Sound LiDAR Consortium / Puget Sound Regional Council
Contact_Address:
Address: 1011 Western Avenue, Suite 500
City: Seattle
State_or_Province: WA
Postal_Code: 98104-5325
Country: USA
Contact_Voice_Telephone: 206-464-5325
Resource_Description: Downloadable Data
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Transfer_Size: 121.089
Metadata_Reference_Information:
Metadata_Date: 20100119
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Watershed Sciences, Inc.
Contact_Address:
Address_Type: mailing address
Address: 4605 NE Fremont St, Suite 211
City: Portland
State_or_Province: OR
Postal_Code: 97213
Country: USA
Contact_Voice_Telephone: 971-223-5152
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile
Metadata_Extensions:
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Profile_Name: ESRI Metadata Profile
Generated by mp version 2.9.6 on Tue Jan 19 11:05:26 2010