View Metadata
Index of Digital Elevation Models (DEM), New York
- Identification Information
- Data Quality Information
- Spatial Data Organization Information
- Spatial Reference Information
- Entity and Attribute Information
- Distribution Information
- Metadata Reference Information
- Identification Information
- Citation
- Originator
- U.S. Geological Survey
- Publication Date
- unknown
- Title
- Index of Digital Elevation Models (DEM), New York
- Geospatial Data Presentation Form
- vector digital data
- Publication Information
- Publication Place
- Reston, VA
- Publisher
- U.S. Geological Survey
- Online Linkage
- https://cugir.library.cornell.edu/catalog/cugir-008186
- Abstract
- This is an index of all the available DEM (digital elevation model) tiles within New York state. Download links are provided for each quad. Each DEM raster has a pixel resolution of approximately 10 meters. Elevation values were derived from USGS contour lines mapped at a scale of 1:24,000.
- Purpose
- DEMs can be used as source data for digital orthophotos and as layers in geographic information systems for earth science analysis. DEMs can also serve as tools for volumetric analysis, for site location of towers, or for drainage basin delineation. These data are collected as part of the National Mapping Program.
- Supplemental Information
- A Digital Elevation Model (DEM) contains a series of elevations ordered from south to north with the order of the columns from west to east. The DEM is formatted as one ASCII header record (A-record), followed by a series of profile records (B-records) each of which include a short B-record header followed by a series of ASCII integer elevations per each profile. The last physical record of the DEM is an accuracy record (C-record). The 7.5-minute DEM (10- by 10-m data spacing, elevations in decimeters) is cast on the Universal Transverse Mercator (UTM) projection (the quads UTM zone can be found in the header record (Record A)) in the North American Datum of 1927. It provides coverage in 7.5- by 7.5-minute blocks. Each product provides the same coverage as a standard USGS 7.5-minute quadrangle, but overedges are published as separate DEM files. Coverage is available for all quads completely contained within New York State, plus some additional ones falling along the borders and containing significant area of the State's land. 7.5-minute DEMs have rows and columns which vary in length and are staggered. The UTM bounding coordinates form a quadrilateral (no two sides are parallel to each other), rather than a rectangle. The user will need to pad out the uneven rows and columns with blanks or flagged data values, if a rectangle is required for the user's application. Some software vendors have incorporated this function into their software for input of standard formatted USGS DEMs.
- Temporal Extent
- Currentness Reference
- process date
- Time Instant
- 1995
- Bounding Box
- West
- -79.75
- East
- -71.75
- North
- 45.0
- South
- 40.5
- Theme Keyword
- digital elevation model
- digital terrain model
- hypsography
- altitude
- topography
- index map
- Theme Keyword Thesaurus
- None
- ISO Topic Category
- elevation
- Theme Keyword
- index map
- elevation
- Theme Keyword Thesaurus
- CUGIR Category
- Place Keyword
- New York
- Place Keyword Thesaurus
- None
- Temporal Keyword
- Access Restrictions
- None
- Use Restrictions
- 1. The NYS DEC and the U.S. Geological Survey asks to be credited in derived products. 2. Secondary Distribution of the data is not allowed. 3. Any documentation provided is an integral part of the data set. Failure to use the documentation in conjunction with the digital data constitutes misuse of the data. 4. Although every effort has been made to ensure the accuracy of information, errors may be reflected in the data supplied. The user must be aware of data conditions and bear responsibility for the appropriate use of the information with respect to possible errors, original map scale, collection methodology, currency of data, and other conditions.
- Status
- Complete
- Maintenance and Update Frequency
- Irregular
- Point of Contact
- Contact Organization
- New York State Department of Environmental Conservation. Division of Water
- Delivery Point
- 625 Broadway
- Delivery Point
- 4th floor
- City
- Albany
- State
- New York
- Postal Code
- 12233-3500
- Contact Telephone
- 518-402-8259
- Contact Electronic Mail Address
- watergis@gw.dec.state.ny.us
- Native Data Set Environment
- 24,000 scale hypsographic contour linework drawn by photogrametric, plane table or other methods by USGS, US Army Corp of Engineers, Tennessee Valley Authority or others. Linework copied onto stable-base mylar. Raster image of linework created by USGS, Reston, with Optronics drum scanner at an aperture of 20um, to give an equivalent resolution of 1024 DPI. Raster data converted to vector with line-center algorithm in LT4X v. 3.1, 11/11/93, by John Dabritz of Infotec Development Inc. Grid elevations calculated with 8-profile weighted linear interpolation, with cubic smoothing of slope at the contour line as per algorithm in above mentioned LT4X v. - export in DEM format, UTM meters, - grid height and width of 10 mt, - clipping (overedge) coordinate in UTM mt, - input coord feet or meters (depending on source material), output in meters/decimeters, - DEM grid points which are on a profile section longer than 80 mt are smoothed by passing the grid through a low pass-filter twice. The filter size (see below) is of 9 cell diameters (aprox 9 mt). The purpose here is to leave well-contoured areas untouched while smoothing areas of less than 5-2.5% slope (to lessen streaking in flat areas typical of multiple-profile DEM derivation). - cubic smoothing of elevation profile across contours to 35% of the distance between adjacent contours. These profiles have a smaller, but still discontinuous change in slope at contour intersection than if not rounded. - 9 cell diameter for smoothing reach, - use all 8 directions (from grid point to N, S, E, W ,NE, NW, SE, SW) for each cell, - no line feeds. export dem contour data name 2 10.00 10.00 2 1 4 80 2 0.35 9 8 0
- Cross-Reference
- Originator
- US Geological Survey
- Publication Date
- unknown
- Title
- Digital Elevation Model (DEM)
- Online Linkage
- http://eros.usgs.gov/guides/dem.html
- Data Quality Information
- Attribute Accuracy Report
- 10 mt gridding cell spacing is the maximun that can be meaningfully extracted from hypsography contour lines. This allows very good hypsographic contour reproduction in all areas except very flat ones. Elevation_resolution_ is 1 decimeter (0.1 meter). Elevation accuracy is 24,000 contour data, i.e. plus/minus half the contour interval.
- Logical Consistency Report
- The fidelity of the relationships encoded in the data structure of the DEM are automatically verified using a USGS software program upon completion of the data production cycle. The test verifies full compliance to the DEM specification.
- Completeness Report
- DEM visually inspected using Delta3D version 2.0, 1995 by John Dabritz and S. Phan of Infotec Development Inc. Checked for completness and drainage characteristics matching the USGS Hydrography Digital Line Graphs published at the same time as the model. Further validation for logical consistency performed previous to submission for archiving.
- Horizontal Positional Accuracy Report
- The horizontal accuracy of the DEM is expressed as an estimated root mean square error (RMSE). The estimate of the RMSE is based upon horizontal accuracy tests of the DEM source materials with equal to or less than intended horizontal RMSE error of the DEM. The testing of horizontal accuracy of the source materials is accomplished by comparing the planimetric (X and Y) coordinates of well-defined ground points with the coordinates of the same points as determined from a source of higher accuracy.
- Quantitative Horizontal Positional Accuracy Assessment
- Lineage
- Source
- Originator
- U.S. Geological Survey
- Publication Date
- Unknown
- Publication Time
- Unknown
- Title
- Albany
- Publication Information
- Publication Place
- EROS Data Center, SD
- Publisher
- U.S. Geological Survey
- Type of Source Media
- mylar separate from original color separation plate
- Source Temporal Extent
- Time Period Information
- Single Date/Time
- Calendar Date
- unknown
- Source Currentness Reference
- ground condition
- Contribution
- elevation values for interpolation
- Source
- Originator
- U.S. Geological Survey or National Geodetic Survey (NGS) (ed.)
- Publication Date
- Unknown
- Publication Time
- Unknown
- Title
- project control
- Publication Information
- Publication Place
- EROS Data Center, SD
- Publisher
- U.S. Geological Survey
- Type of Source Media
- field notes
- Source Temporal Extent
- Time Period Information
- Single Date/Time
- Calendar Date
- unknown
- Source Currentness Reference
- ground condition
- Contribution
- ground control points
- Source
- Originator
- U.S. Geological Survey (ed.)
- Publication Date
- Unknown
- Publication Time
- Unknown
- Title
- photo ID number
- Publication Information
- Publication Place
- EROS Data Center, SD
- Publisher
- U.S. Geological Survey
- Type of Source Media
- transparency
- Source Temporal Extent
- Time Period Information
- Single Date/Time
- Calendar Date
- unknown
- Source Currentness Reference
- ground condition
- Spatial Data Organization Information
- Direct Spatial Reference Method
- Vector
- Point and Vector Object Information
- SDTS Terms Description
- SDTS Point and Vector Object Type
- G-polygon
- Point and Vector Object Count
- 961
- Spatial Reference Information
- Horizontal Coordinate System Definition
- Planar
- Grid Coordinate System
- Grid Coordinate System Name
- Universal Transverse Mercator
- Universal Transverse Mercator
- UTM Zone Number
- 17 or 18 or 19
- Transverse Mercator
- Scale Factor at Central Meridian
- .9996
- Longitude of Central Meridian
- +075.000000
- Latitude of Projection Origin
- +00.000000
- False Easting
- 0
- False Northing
- 0
- Planar Coordinate Information
- Planar Coordinate Encoding Method
- row and column
- Coordinate Representation
- Abscissa Resolution
- 10
- Ordinate Resolution
- 10
- Planar Distance Units
- Meters
- Geodetic Model
- Horizontal Datum Name
- North American Datum of 1927
- Ellipsoid Name
- Clarke 1866
- Semi-major Axis
- 6378206.4
- Denominator of Flattening Ratio
- 294.9787
- Vertical Coordinate System Definition
- Altitude System Definition
- Altitude Datum Name
- National Geodetic Vertical Datum of 1929
- Altitude Resolution
- 1
- Altitude Distance Units
- decimeters
- Altitude Encoding Method
- Explicit elevation coordinate included with horizontal coordinates
- Entity and Attribute Information
- Entity and Attribute Overview
- The digital elevation model is composed of an elevation value linked to a grid cell location representing a gridded form of a topographic map hypsography overlay. Each grid cell entity contains an 8-character value between -32,767.0 and 32,768.0.
- Entity and Attribute Detail Citation
- U.S. department of the Interior, U.S. Geological Survey, 1992, Standards for digital elevation models: Reston, VA, a hypertext version of the Digital Elevation Model (DEM) is available at: http://eros.usgs.gov/guides/dem.html (see Cross Reference)
- Distribution Information
- Format Name
- GeoJSON
- Format Name
- metadata
- Format Name
- HTML metadata
- Distributor
- Albert R. Mann Library
- Online Access
- https://cugir-data.s3.amazonaws.com/00/81/86/cugir-008186-index.geojson
- Online Access
- https://cugir-data.s3.amazonaws.com/00/81/86/fgdc.xml
- Online Access
- https://cugir-data.s3.amazonaws.com/00/81/86/fgdc.html
- Name
- Metadata Reference Information
- Metadata Date
- 20190524
- Metadata Contact
- Contact Information
- Contact Organization Primary
- Contact Organization
- Albert R. Mann Library
- Contact Address
- Address
- Albert R. Mann Library
- City
- Ithaca
- State or Province
- New York
- Postal Code
- 14853
- Country
- USA
- Contact Voice Telephone
- 607-255-5406
- Contact Electronic Mail Address
- mann-ref@cornell.edu
- Metadata Standard Name
- FGDC Content Standard for Digital Geospatial Metadata
- Metadata Standard Version
- FGDC-STD-001-1998