GIS Library Contents - Metadata USGS NED 10-Meter Contours

This metadata information is subject to our disclaimer. Metadata information presented here is maintained manually. Therefore, date-sensitive fields such as date of last update may not be up-to-date. All metadata is subject to errors inherent in a manual process.

Descriptive name		USGS NED 10-Meter Contours
File name		cn10mned
Spatial domain		Pima County
Abstract		CN10MNED is a 10-meter contour layer covering the full extent of Pima County. It was created from the most-recent 1/3-arc-second U.S. Geological Survey National Elevation Dataset (NED) DEMs, some of them part of the 3DEP program. This layer is so large that the decision was made to only store it in the enterprise geodatabase, rather than convert it to shapefile format. Although it has a coarser vertical resolution than some of the other contour layers in the Library, it has the advantage of full, seamless coverage for the entire county.
Known errors/qualifications		It may be difficult to export this layer due to its size. The feature class is 671 MB and a shapefile created from the feature class would be 1.08 GB. The "Published Enterprise GDB" date is a fictitious value in the metadata so that the metadata has a date that's guaranteed to be older than any generated metadata thumbnail PDF. Since the Library Manager doesn't set this date for "GDB No Export" maintenance format (as it should), the fictitious date was entered so the GIS Library Thumbnails job would run.
Feature type		line
Feature count		58,652
Thumbnail Map		cn10mned.pdf    (67,047,459 bytes, PDF created 07/19/2022 )
Projection		NAD83 HPGN (Parameters)
Rectification		unknown
Field/value metadata		Field metadata
Source organization		U.S. Geological Survey
Source contact
Source document or file name		multiple files
Source date		20170718
Source scale
Source format		Grid
Date of last data update (This date may not be current.)		20170725
Last data update by		Erik Glenn
Date/time last touched - Meaning?		2021-01-14  10:38 PM - Enterprise GDB - Library input format
		- The Shapefile date was not found.
		See coverage files, if any, for date.
Lineage		20170725 -- After downloading eight different 1/3-arc-second grids, covering the entirety of Pima County, all files were converted to 32-bit floating-point tiled TIFFs with LZW compression. The eight TIFFs were reprojected and mosaicked into one TIFF, and then that raster dataset was smoothed using a low-pass 3-by-3 mean value filter. Ten-meter contours were generated from the smoothed TIFF and then clipped to Pima County. Extremely short contours (<30 feet) were removed. (EG)
On maintenance?		Not required
Maintenance organization
Maintenance description
Original conversion by		Erik Glenn
Pima County ITD GIS contact		Erik Glenn
Alternate Pima County ITD GIS contact
On  Pima County Geospatial Data Portal?		No

 GIS Library Data Layer Metadata