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Short Citation:
OCM Partners, 2023: 2007 USFS Lidar DEM: Biscuit Fire, https://www.fisheries.noaa.gov/inport/item/57767.

Item Identification

Title: 2007 USFS Lidar DEM: Biscuit Fire
Short Name: or2007_biscuit_dem_m8875
Status: Completed
Creation Date: 2019-09-25
Abstract:

No metadata record for this data set was provided to the NOAA Office for Coastal Management (OCM). This record was created with information from the data report. A link to the data report is provided in the URL section of this metadata record.

Watershed Sciences, Inc. (WS) collected Light Detection and Ranging (LiDAR) data for the USDA Forest Service on September 19-23, 2007. The Areas of Interest (AOIs) collectively cover 36,837 acres (6 sites) within the Biscuit Fire region of Southwest Oregon. The overriding objective of the LiDAR acquisition was to provide accurate vegetation and bare earth terrain models to be used in the evaluation of landscape patterns on forestland affected by the fire of July 2002.

In addition to these bare earth Digital Elevation Model (DEM) data, the lidar point data that these DEM data were created from, are also available. These data are available for custom download at the link provided in the URL section of this metadata record.

Purpose:

The overriding objective of the LiDAR acquisition was to provide accurate vegetation and bare earth terrain models to be used in the evaluation of landscape patterns on forestland affected by the fire of July 2002.

Keywords

Theme Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
UNCONTROLLED
ISO 19115 Topic Category elevation
None DEM
None digital
None laser
None lidar
None model
None Topography

Spatial Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Location Keywords
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
Global Change Master Directory (GCMD) Location Keywords
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > OREGON
Global Change Master Directory (GCMD) Location Keywords
VERTICAL LOCATION > LAND SURFACE
UNCONTROLLED
None Continent > North America > United States Of America > Oregon > Curry County
None Continent > North America > United States Of America > Oregon > Josephine County

Instrument Keywords

Thesaurus Keyword
UNCONTROLLED
Global Change Master Directory (GCMD) Instrument Keywords Earth Remote Sensing Instruments > Active Remote Sensing > Profilers/Sounders > Lidar/Laser Sounders > LIDAR > Light Detection and Ranging

Platform Keywords

Thesaurus Keyword
UNCONTROLLED
Global Change Master Directory (GCMD) Platform Keywords Aircraft > Aircraft

Physical Location

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

Data Set Information

Data Set Scope Code: Data Set
Data Set Type: Elevation
Maintenance Frequency: None Planned
Data Presentation Form: Model (Digital)
Distribution Liability:

Any conclusions drawn from the analysis of this information are not the responsibility of the USDA Forest Service, DOGAMI, NOAA, the Office for Coastal Management or its partners.

Data Set Credit: USDA Forest Service

Support Roles

Data Steward

CC ID: 879696
Date Effective From: 2019
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: 879697
Date Effective From: 2019
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: 879698
Date Effective From: 2019
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: 879699
Date Effective From: 2019
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: 879718
W° Bound: -124.241154
E° Bound: -123.703325
N° Bound: 42.6101
S° Bound: 42.214247
Description

Biscuit Fire project area.

Extent Group 1 / Time Frame 1

CC ID: 879717
Time Frame Type: Range
Start: 2007-09-19
End: 2007-09-23
Description:

Dates of collection.

Spatial Information

Reference Systems

Reference System 1

CC ID: 879737

Coordinate Reference System

CRS Type: Vertical
EPSG Code: EPSG:5703
EPSG Name: NAVD88 height
See Full Coordinate Reference System Information

Reference System 2

CC ID: 879736

Coordinate Reference System

CRS Type: Projected
EPSG Code: EPSG:26910
EPSG Name: NAD83 / UTM zone 10N
See Full Coordinate Reference System Information

Access Information

Security Class: Unclassified
Data Access Procedure:

Data is available online for bulk and custom downloads.

Data Access Constraints:

None

Data Use Constraints:

Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations.

Distribution Information

Distribution 1

CC ID: 879700
Start Date: 2019-07-10
End Date: Present
Download URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8875
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2019 - Present)
File Name: Customized Download
Description:

Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base.

File Type: Zip
Compression: Zip

Distribution 2

CC ID: 879701
Start Date: 2019-07-10
End Date: Present
Download URL: https://coast.noaa.gov/htdata/raster2/elevation/OLC_Biscuit_2007_8875
Distributor: NOAA Office for Coastal Management (NOAA/OCM) (2019 - Present)
File Name: Bulk Download
Description:

Bulk download of DEM files in GeoTiff format, UTM Zone 10N coordinates, orthometric heights.

File Type: GeoTIFF

URLs

URL 1

CC ID: 879702
URL: https://coast.noaa.gov/dataviewer/
Name: NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV)
URL Type:
Online Resource
File Resource Format: HTML
Description:

The Data Access Viewer (DAV) allows a user to search for and download elevation, imagery, and land cover data for the coastal U.S. and its territories. The data, hosted by the NOAA Office for Coastal Management, can be customized and requested for free download through a checkout interface. An email provides a link to the customized data, while the original data set is available through a link within the viewer.

URL 2

CC ID: 879703
URL: https://coast.noaa.gov/htdata/lidar3_z/geoid12b/data/8874/supplemental/or2007_biscuit_fire_m8874.kmz
Name: Browse graphic
URL Type:
Browse Graphic
File Resource Format: KML
Description:

This graphic displays the footprint for this lidar data set.

URL 3

CC ID: 879704
URL: https://coast.noaa.gov/htdata/lidar3_z/geoid12b/data/8874/supplemental/Biscuit_LIDAR_Report.pdf
Name: Data report
URL Type:
Online Resource
File Resource Format: pdf
Description:

Link to the Data Report.

URL 4

CC ID: 879705
URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8874
URL Type:
Online Resource
Description:

Link to custom download the lidar point data from which these raster Digital Elevation Model (DEM) data were created.

Data Quality

Vertical Positional Accuracy:

A total of 673 control points were collected for this project.

Absolute accuracy = 4 cm RMSE

Data Management

Have Resources for Management of these Data Been Identified?: Yes
Approximate Percentage of Budget for these Data Devoted to Data Management: Unknown
Do these Data Comply with the Data Access Directive?: Yes
Actual or Planned Long-Term Data Archive Location: NCEI-CO
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?:

Data is backed up to tape and to cloud storage.

Lineage

Lineage Statement:

Watershed Sciences, Inc., collected Light Detection and Ranging (LIDAR) data in the Biscuit Fire project area for the USDA Forest Service.

NOAA OCM received the data from DOGAMI and ingested it into the Digital Coast Data Access Viewer for distribution.

Sources

processed lidar data

CC ID: 879711
Contact Role Type: Originator
Contact Type: Organization
Contact Name: Wateshed Sciences, Inc.

raw lidar data

CC ID: 879710
Contact Role Type: Originator
Contact Type: Organization
Contact Name: Watershed Sciences, Inc.

Process Steps

Process Step 1

CC ID: 879712
Description:

Acquisition.

The full survey was conducted on September 19-23, 2007 (Julian Days 262-266). The LiDAR survey uses a Leica ALS50 Phase II laser mounted in a Cessna Caravan 208B. The sensor scan angle was ±14o from nadir1 with a pulse rate designed to yield an average native density (number of pulses emitted by the laser system) of ≥ 4 points per square meter over terrestrial surfaces. The Leica ALS50 Phase II system allows up to four range measurements (returns) per pulse, and all discernable laser returns are processed for the output dataset. It is not uncommon for some types of surfaces (e.g. dense vegetation or water) to return fewer pulses than the laser originally emitted. These discrepancies between ‘native’ and ‘delivered’ density will vary depending on terrain, land cover and the prevalence of water bodies. To accurately solve for laser point position (geographic coordinates x, y, z), the positional coordinates of the airborne sensor and the attitude of the aircraft are recorded continuously throughout the LiDAR data collection mission. Aircraft position is measured twice per second (2 Hz) by an onboard differential GPS unit. Aircraft attitude is measured 200 times per second (200 Hz) as pitch, roll and yaw (heading) from an onboard inertial measurement unit (IMU). To allow for post-processing correction and calibration, aircraft/sensor position and attitude data are indexed by GPS time.

Process Date/Time: 2007-09-23 00:00:00

Process Step 2

CC ID: 879715
Description:

Ground Survey

Simultaneous with the airborne data collection mission, we conduct a static (1 Hz recording frequency) survey of the horizontal and vertical positions of one or more survey control base stations established over monuments with known coordinates.

Indexed by time, these GPS data are used to correct the continuous onboard measurements of aircraft position recorded throughout the mission. Multiple sessions are processed over the same monument to confirm antenna height measurements and reported position accuracy. After the airborne survey, these static GPS data are processed using triangulation with Continuously Operating Reference Stations (CORS) stations, and checked against the Online Positioning User Service (OPUS2) to quantify daily variance. Controls are located within 13 nautical miles of the mission area. Ground truth points are collected using a GPS based real-time kinematic (RTK) survey. For an RTK survey, the ground crew uses a roving unit to receive radio-relayed corrected positional coordinates for all ground points from a GPS base unit set up over a survey control monument. The roving unit records precise location measurements with an error (σ) of ≤ 1.5 cm (0.6 in). 673 RTK ground points were collected in the Biscuit Fire Study Area.

Process Step 3

CC ID: 879714
Description:

Laser Point Processing

Laser point coordinates are computed using the IPAS and ALS Post Processor software suites based on independent data from the LiDAR system (pulse time, scan angle), and aircraft trajectory data (SBET). Laser point returns (first through fourth) are assigned x, y, z coordinates along with unique intensity values (0-255). The data are output into large LAS v. 1.1 files; each point maintains the corresponding scan angle, return number (echo), intensity, and x, y, z (easting, northing, and elevation) information. These initial laser point files are too large for subsequent processing. To facilitate laser point processing, bins (polygons) are created to divide the dataset into manageable sizes (< 500 MB). Flightlines and LiDAR data are then reviewed to ensure complete coverage of the study area and positional accuracy of the laser points. Laser point data are imported into processing bins in TerraScan, and manually calibrated to assess the system offsets for pitch, roll, heading and scale (mirror flex). Using a geometric relationship developed by Watershed Sciences, each of these offsets is resolved and corrected if necessary.

LiDAR points are then filtered for noise, artificial low points (‘pits’) or non-terrestrial high points (e.g., birds, clouds, vapor, haze) by screening for absolute elevation limits, isolated points and height above ground. Each bin is then inspected for remaining spurious points which are then manually removed. In a bin containing approximately 7.5-9.0 million points, an average of 50-100 points are typically found to be artificially low or high. Where there is dense vegetation and/or at breaks in terrain, steep slopes and at bin boundaries, the delivered density can be significantly less than the native density. In areas where it is determined that the ground surface model has failed, supervised classifications are performed by ‘reseeding’ the ground surface model with ground points. Internal calibration is refined using TerraMatch. Points from overlapping lines are tested for internal consistency and final adjustments are made for system misalignments (i.e., pitch, roll, heading offsets and scale). Automated sensor attitude and scale corrections yield 3-5 cm improvements in the relative accuracy. Once system misalignments are corrected, vertical GPS drift is then resolved and removed per flight line, yielding a slight improvement (<1 cm) in relative accuracy.

The TerraScan software suite is designed specifically for classifying near-ground points (Soininen, 2004). The processing sequence begins by ‘removing’ all points that are not ‘near’ the earth based on geometric constraints used to evaluate multi-return points. The resulting bare earth (ground) model is visually inspected and additional ground point modeling is performed in site-specific areas to improve ground detail. This manual editing of ground occurs in areas with known ground modeling deficiencies, such as bedrock outcrops, cliffs, deeply incised stream banks, and dense vegetation. In some cases, automated ground point classification includes known vegetation (i.e., understory, low/dense shrubs, etc.). These points are manually reclassified as non-ground. Where it is determined that the ground model has failed (usually under dense vegetation and/or at breaks in terrain, steep slopes and at bin boundaries), supervised classifications are performed by ‘reseeding’ the ground model. Ground surface rasters are developed from triangulated irregular networks (TINs) of ground points.

Process Step 4

CC ID: 879713
Description:

The NOAA Office for Coastal Management (OCM) received 23 bare earth DEM files in Arc Grid format from DOGAMI. The data were in UTM Zone 10N, NAD83, meters, coordinates and NAVD88 (Geoid03) elevations in meters. The EPSG codes (Vertical - 5703, Horizontal - 26910) were assigned. For ingest into the Digital Coast Data Access Viewer, and to adhere to the Open Data Policy, data were converted to GeoTiff format.

Process Date/Time: 2019-09-25 00:00:00
Process Contact: NOAA Office for Coastal Management (NOAA/OCM)
Phone (Voice): (843) 740-1202
Email Address: coastal.info@noaa.gov
Source: processed lidar data

Catalog Details

Catalog Item ID: 57767
GUID: gov.noaa.nmfs.inport:57767
Metadata Record Created By: Rebecca Mataosky
Metadata Record Created: 2019-09-25 16:28+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2022-08-09 17:11+0000
Metadata Record Published: 2019-09-25
Owner Org: OCMP
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Last Review Date: 2019-09-25
Metadata Review Frequency: 1 Year
Metadata Next Review Date: 2020-09-25