The Ridge Feature Protection layer was developed using best available elevation data and the Geomorphon Landforms geoprocessing tool available thru Esri ArcGIS Pro software.\\u00a0 The Geomorphon Landforms geoprocessing tool is based on a powerful algorithm that combines elevation differences and visibility concepts to classify terrain into landform types.\\u00a0 A geomorphon is a representation of landscape based on elevation differences within the surrounding area of a target cell.\\u00a0
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The following parameters and data refinements were used for the Geomorphon Landforms geoprocessing tool in order to provide a general representation of primary and other prominent ridge features in Loudoun County.
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Parameters:
[Flat Angle Threshold = 3 degrees, Search Distance = 2,640 feet (1/2 mile), and Skip Distance = 660 feet (1/8 mile), Landform Values = Peak, Ridge OR Shoulder]\\u00a0
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Data Refinements:
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The Ridge Feature Protection layer is intended to be used only as a reference.\\u00a0\\u00a0Better site-specific elevation data may improve the precision and accuracy of the Ridge Features layer. To assure that Loudoun County is using the best available elevation data, please provide the Office of Mapping and Geographic Information with information concerning any errors, omissions, or other discrepancies discovered in this data.
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Source Data
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Digital Elevation Model/DEM (~ 10 m cell size)
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USGS 1/3 Arc Second; 3D Elevation Program (3DEP)
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These data were generated for use by Loudoun County, Virginia and are available to the public. These data are intended for use at 1:2400 scale or smaller. Acknowledgement of Loudoun County would be appreciated in products derived from this data.