Loudoun Ridge Feature Protection

More Metadata The Ridge Feature Protection layer was developed using best available elevation data and the Geomorphon Landforms geoprocessing tool available thru Esri ArcGIS Pro software. The Geomorphon Landforms geoprocessing tool is based on a powerful algorithm that combines elevation differences and visibility concepts to classify terrain into landform types. A geomorphon is a representation of landscape based on elevation differences within the surrounding area of a target cell. 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. 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] Data Refinements: All features outside of the MOD were removed. All features within the MOD but below the critical elevation defined within the MOD were removed. All features within MOD less than 20 acres in size and not contiguous with the County’s boundary were removed. All features within MOD not contiguous with a primary ridge feature were removed. All features within MOD contiguous with a primary ridge feature but 400 feet or more in elevation below the primary ridge feature were removed. The Ridge Feature Protection layer is intended to be used only as a reference. Better 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. Source Data Digital Elevation Model/DEM (~ 10 m cell size) USGS 1/3 Arc Second; 3D Elevation Program (3DEP)