{"@type": "dcat:Dataset", "accessLevel": "public", "contactPoint": {"@type": "vcard:Contact", "fn": "SeattleData", "hasEmail": "mailto:mapgis.mapgis@seattle.gov"}, "description": "<span>City of Seattle 2 ft contours derived from Lidar captured in 2021.\n Contour lines display at 2ft, 10ft and 50ft intervals dependent on \nscale. Lines have been smoothed and generalized for display and \nperformance.<br />\n  <br />\nDevelopment Detail:<br />\n  <br />\nThis vector tile service includes topographic contour lines representing\n elevation at 2-foot intervals within the city of Seattle. <br />\n  <br />\nThe contours were derived from a bare earth - digital elevation model \n(DEM) with a pixel resolution of 1.5 feet. The lidar data that created \nthe DEM were collected by NV5 Geospatial over the spring and summer \nmonths of 2021 and provided to the city by King County in 2022. <br />\n  <br />\nThe DEM used to generate the contours was filtered using the Focal \nStatistics tool in ArcGIS, which served to limit some abrupt changes in \ncell values. A 3x3 rectangular neighborhood analysis was applied and a \nmean value was calculated per raster cell. <br />\n  <br />\nAfter running the Focal Statistics tool, 2-foot contours were generated \nfrom the filtered DEM. To reduce file size and improve performance, the \ncontours were generalized further using the Smooth Line tool in ArcGIS. A\n smoothing algorithm type of Polynomial Approximation with Exponential \nKernel (PAEK) and a smoothing tolerance of 20 feet was selected in the \nSmooth Line tool parameter options. <br />\n  <br />\nFinally, after executing both generalization tools (Focal Statistics and\n Smooth Line), all lines less than 25 feet in length were omitted from \nthe final output. <br />\n  <br />\nPlease note: The 2-foot contours are intended to be used for general \nreference and cartographic purposes only and should not be used for \nanalysis purposes.</span>", "distribution": [{"@type": "dcat:Distribution", "downloadURL": "https://data-seattlecitygis.opendata.arcgis.com/maps/SeattleCityGIS::contours", "mediaType": "text/html", "title": "ArcGIS Hub Dataset"}, {"@type": "dcat:Distribution", "downloadURL": "https://tiles.arcgis.com/tiles/ZOyb2t4B0UYuYNYH/arcgis/rest/services/Contours/VectorTileServer", "mediaType": "application/json", "title": "ArcGIS GeoService"}], "identifier": "https://www.arcgis.com/home/item.html?id=42f59a16f8cd4c27b48698083de9e32b", "issued": "2022-08-30", "keyword": ["seattle gis open data", "contours", "seattle"], "landingPage": "https://data-seattlecitygis.opendata.arcgis.com/maps/SeattleCityGIS::contours", "modified": "2024-10-22", "publisher": {"@type": "org:Organization", "name": "City of Seattle ArcGIS Online"}, "spatial": "-122.4399,47.4331,-122.2068,47.7812", "theme": ["geospatial"], "title": "Contours"}