2016 USFS Lidar: Fremont-Winema National Forest - Cherry Creek

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.

LiDAR data acquisition occurred between July and October 2016. The Atlantic Group, LLC successfully completed lidar acquisition for the Fremont-Winema, Willamette, Deschutes, and Umpqua National Forests areas of interest (AOI). This metadata record describes the Cherry Creek project area in the Fremont-Winema National Forest which is a subset of the larger collection. The lidar for the larger AOI was acquired in fifty (50) flight missions completed on October 25th, 2016. The total project area encompasses 1,275,059 acres, 5,160 square kilometers or 1,992 square miles.

The primary purpose of the lidar survey was to establish measurements of the bare earth surface, as well as top surface feature data for providing geometric inputs for modeling, other numerical modeling and economic related assessments.

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 is available online for bulk and custom downloads.

None

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be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions.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.

As described in Section 7.5 of the ASPRS Positional Accuracy Standards for Digital Geospatial Data, the horizontal errors in lidar data are largely a function of GNSS positional error, INS angular error, and flying altitude. Therefore, lidar data collected with GNSS error of 8cm and the IMU error of 0.00427 degrees at an altitude of 1,965m; the expected radial horizontal positional error will be RMSEr = 28.5cm.

A total of three hundred and five (305) control points were collected for this project. Point cloud data accuracy was tested against a Triangulated Irregular Network (TIN) constructed from lidar points in clear and open areas. A clear and open area can be characterized with respect to topographic and ground cover variation such that a minimum of 5 times the NPS exists with less than 1/3 of the RMSEZ deviation from a low-slope plane. Slopes that exceed 10 percent were avoided.

Below are the vertical accuracy reporting requirements for this project:

Vertical Accuracy Reporting Requirements in Meters:

RMSEZ ≤ 10.0cm (Bare-Earth)

FVA ≤ 19.6cm 95% Confidence Level (Bare-Earth)

Vertical Accuracy Reporting Requirements in Feet:

RMSEZ ≤ 0.328ft (Bare-Earth)

FVA ≤ 0.643ft 95% Confidence Level (Bare-Earth)

*The terms FVA (Fundamental Vertical Accuracy), SVA (Supplemental Vertical Accuracy) and CVA (Consolidated Vertical Accuracy) are from the National Digital Elevation Program (NDEP) Guidelines for Digital Elevation Data (2004). The term FVA refers to open terrain, urban and levee classes; the term SVA refers to classes tested that are in addition or supplemental to the open terrain; the term CVA refers to the consolidated accuracy of the data from all classes (FVA + SVA).

FVA is 0.132 m or 6.7 cm RMSE

CVA is 0.072 m

Data is backed up to tape and to cloud storage.

The Atlantic Group, LLC, collected Light Detection and Ranging (LIDAR) data in the Thomas Creek area for the USDA Forest Service.

NOAA OCM has taken the data and ingested it into the Digital Coast Data Access Viewer for distribution.