2007 Northwest Florida Water Management District (NWFWMD) Lidar: Holmes County

LIDAR-derived binary (.las) files containing points classified as bare-earth and canopy (first return) were produced for the 2007/2008 Northwest Florida Water Management District - 5 Counties (Calhoun, Holmes, Washington, Jackson and Liberty), Florida lidar mapping project. The files were provided in a scheme of FDEM-derived 5,000 x 5,000 foot (1500 x 1500 meter) tiles. When initially processed, horizontal mapping units were in UTM meters, vertical mapping units are in U.S. survey feet. The total mapping area covers approximately 2102 square miles.

Original contact information:

Contact Name: Mr John Crowe

Contact Org: Northwest Florida Water Management District

Title: Associate Hydrologist, Division of Resource Management

Phone: 850-539-5999

Email: ron.bartel@nwfwmd.state.fl.us

FEMA map modernization, digital elevation model, planning, topographic interpretation

10517

A footprint of this data set may be viewed in Google Earth at:

https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/576/supplemental/2007_NWFWMD_Lidar_Holmes_County.kmz

Any conclusions drawn from analysis of this information are not the responsibility of the Northwest Florida Water Management District (NWFWMD),

the NOAA Office for Coastal Management or its partners.

This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer. The data set is dynamically generated based on user-specified parameters.

;

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may no longer represent actual surface conditions.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 base critical applications on this data set without full

awareness of potential limitations.

Microsoft Windows XP version 5.1 (Build 2600, Service Pack 2); ArcGIS Desktop 9.1; ArcGIS Workstation 9.1; MARS 4.0

Verification of attribute accuracy of LIDAR data involves the use of filtering techniques. Auto-filtering uses algorithms to reclassify data in the point cloud. Hand-filtering involves the use of a technician working in a graphic environment to reclassify the erroneous points that may remain in the LIDAR point cloud after auto filter. | Quantitative Value: n/a | Quantitative Test Explanation: n/a

Horizontal accuracy is verified in three tests. During bore sighting, adjoining flight lines are view in profile and hard edged features are observed and if necessary the flight lines are adjusted for good relative horizontal and vertical fit. The second test for horizontal accuracy is by comparing raw contours from each flight line against adjoining flight lines at specific points. The final test is the vertical LIDAR control report.

Survey control points were used to validate the accuracy of the LIDAR surface model after automatic and hand filtering. This surface exceeds the NSSDA vertical accuracy specifications of 1.2 ft.; Quantitative Value: 0.149352 meters, Test that produced the value: This value is measured as RMSEz.; Quantitative Value: 0.15448 meters, Test that produced the value: This value is measured as vertical accuracy.

Cloud Cover: 0

This dataset contains classified returns of the LIDAR sensor. The sensor data was verified in MARS software to ensure complete coverage.

Calibrations of the LIDAR flight line data are performed; this process is known as bore sighting. The flight lines are compared to evaluate both their relative and absolute accuracies.