ElevationOther_HILSHD10M

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator:

Database Adminstrator, VT Center for Geographic Information, Inc.

Publication_Date: 20120210

Publication_Time: unknown

Title: ElevationOther_HILSHD10M

Edition: 2012

Geospatial_Data_Presentation_Form: raster digital data

Series_Information:

Series_Name:

Hillshading generated from USGS National Elevation Dataset (NED)ElevationDEM_DEM10M data

Issue_Identification: 0.1

Publication_Information:

Publication_Place: Waterbury, VT 05676

Publisher: Mike Brouillette

Other_Citation_Details: ElevationOther_HILSHD10M

Description:

Abstract:

Used ElevationDEM_DEM10M and the Arc/Info HILLSHADE command with "Shade", "z_units = .3048", azimuth = 315 degrees and altitude = 45 degrees options to create this data layer. Input source dataset is derived from the multi-resolution National Elevation Dataset (NED), at resolutions of both 1/3 arc-second (approx. 10 meters) and in limited areas, 1/9 arc-second (approx. 3 meters). VCGI extracted the Vermont portion of the NED and re-projected into Vermont State Plane Meters NAD83 (vertical units in feet). Production artifacts were filtered out of this source data prior to acquisition resulting in a much-improved base of elevation data for calculating contours, slope and hydrologic derivatives. The NED is the primary elevation data product produced and distributed by the USGS. The NED provides the best available public domain raster elevation data of the conterminous United States, Alaska, Hawaii, and territorial islands in a seamless format. The NED is derived from diverse source data, processed to a common coordinate system and unit of vertical measure. The source data are distributed in geographic coordinates in units of decimal degrees, and in conformance with the North American Datum of 1983 (NAD 83). The source elevation values are provided in units of meters, and are referenced to the North American Vertical Datum of 1988 (NAVD 88) over the conterminous United States.

Purpose:

Hillshading generated from ElevationDEM_DEM10M (USGS 1/3 arc-second NED <http://seamless.usgs.gov/products/3arc.php>)

Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: Time_of_Day Unknown

Currentness_Reference: Publication Date

Status:

Progress: Complete

Maintenance_and_Update_Frequency: Unknown

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -73.454162

East_Bounding_Coordinate: -71.465281

North_Bounding_Coordinate: 45.018361

South_Bounding_Coordinate: 42.722789

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword:

Hillshading generated from ElevationDEM_DEM10M (USGS 1/3 arc-second NED)

Theme_Keyword: elevation

Theme_Keyword: shadows

Theme_Keyword: terrain

Theme_Keyword: topographic

Theme_Keyword: topography

Place:

Place_Keyword_Thesaurus: None

Place_Keyword: Statewide

Place_Keyword: Vermont

Stratum:

Stratum_Keyword_Thesaurus: None

Stratum_Keyword: Stratum_Keyword

Temporal:

Temporal_Keyword_Thesaurus: None

Temporal_Keyword: Temporal_Keyword

Access_Constraints:

VCGI and the State of VT make no representations of any kind, including but not limited to the warranties of merchantability or fitness for a particular use, nor are any such warranties to be implied with respect to the data.

Use_Constraints:

No assessment of the accuracy of DEM data or data products has been made by VCGI. Data users should assess DEM data products for appropriate use in a given project.

Point_of_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: VT Center for Geographic Information

Contact_Address:

Address_Type: Mailing and Physical Address

Address: 1 National Life Dr, Dewey Building, 2nd Floor

City: Montpelier

State_or_Province: VT

Postal_Code: 05620-2001

Country: USA

Contact_Voice_Telephone: (802) 585-0820

Contact_TDD/TTY_Telephone: None

Contact_Facsimile_Telephone:

Contact_Electronic_Mail_Address: vcgi@vermont.gov

Hours_of_Service: 9am - 5pm, M-F

Data_Set_Credit: Mike Brouillette

Security_Information:

Security_Classification_System: N/A

Security_Classification: Unclassified

Security_Handling_Description: No Security Considerations

Native_Data_Set_Environment: A/I GRID

Data_Quality_Information:

Logical_Consistency_Report: N/A

Completeness_Report: N/A

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report:

See <http://ned.usgs.gov/downloads/documents/NED_Accuracy.pdf> for details of the methodology. The claimed vertical accuracy for 7.5 min quads (source contours for NED) is that contours have an allowable horizontal placement error of half the distance to the adjacent contours, 90% of the time.

Lineage:

Process_Step:

Process_Description:

Input ElevationDEM_DEM10M into the Arc/Info HILLSHADE command with "Shade", "z_units = .3048", azimuth = 315 degrees and altitude = 45 degrees options to create this data layer. Compressed, and loaded into VGIS Data Warehouse by Mike Brouillette.

Process_Date: 2/10/2012

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Mike Brouillette

Contact_Organization: VCGI

Process_Step:

Process_Description:

Downloaded NED tiles from "The National Map" and using ArcGIS mosaiced individual tiles into a single, master raster dataset covering the extent of Vermont plus all Watershed Boundary Dataset (WBD) subbasin boundaries that intersect the state. Converted the elevation values into WHOLE units of FEET (to support INTEGER Raster type) and reprojected (via cubic convolution option) from the GCS projection (Datum of NAD83) into Vermont State Plane Coordinates (Datum in NAD83) as a 10m resolution "Interger" type grid with an origin to the nearest hundreth, i.e., coincident with the standardized VCGI spatial domain. Whole feet elevation values supporting the Integer type output greatly reduce its size and improve related processing operations. Final grid extent then "masked" to the buffered extent of the state outlined plus a buffer of 2,000 meters. Compressed, and loaded into VGIS Data Warehouse by Mike Brouillette.

Process_Date: 2/10/2012

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Mike Brouillette

Contact_Organization: VCGI

Process_Step:

Process_Description:

(USGS) NED assembly and updating are accomplished with a highly automated production process that was developed specifically for this seamless elevation data set. The selection of source data is accomplished by an automated query of a database of USGS and partner-supplied DEMs. The "best available" data criteria are applied to select specific file-based DEMs from the database. The headers of the selected DEMs are read to create an index, which controls production and triggers subsequent processing steps. Industry standard tools from the National Geodetic Survey, NADCON and VERTCON, are used to perform horizontal and vertical datum transformations, respectively.The source DEMs are projected from their native coordinate system to a geographic coordinate system (decimal degrees of latitude and longitude) using standard cartographic transformation software. Resampling of the original elevation values is done with an implementation of cubic convolution that is optimized for elevation data by maintaining the integrity of shorelines and water bodies. Artifact removal is performed on the older USGS Level 1 DEMs that were produced with photogrammetric methods. The "mean profile filter" was specifically designed to process these 7.5-minute DEMs. The filter process uses a series of directional filters to isolate the high-frequency artifacts, which are then subtracted from the DEM. The magnitude of these artifacts is small, typically less than 1 meter, so the change to the DEM is negligible, but the removal results in significant improvements in derivative elevation products, such as shaded relief, slope, and aspect. The final steps in the production process include paneling the DEMs to fill the 1- by 1-degree tile, filling slivers of missing data along DEM boundaries as necessary by interpolating adjacent values, and edge matching the seams along the DEM boundaries and tile edges. The edge match algorithm uses a feathering approach that maintains local slope continuity across the seam. Finally, a shaded-relief image of the tile is generated for inspection by an analyst to verify successful processing, especially artifact filtering and edge matching. In some cases, DEM header information, which automatically triggers certain processing options, is incorrect, and the result is data that are not acceptable for inclusion into the NED. These cases are detected in the visual inspection step, the DEM header is corrected, and the tile is submitted for reprocessing. Tiles passing inspection are transferred to the next release version, and the spatially referenced metadata are updated accordingly. The metadata were created for The National Map Seamless Server at <http://seamless.usgs.gov>, and are available in several formats: HTML, TEXT, XML, FAQ and SGML.

Process_Date: Ongoing

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: U.S. Geological Survey

Contact_Position: Customer Service Representative

Contact_Address:

Address_Type: mailing and physical address

Address: USGS Earth Resources Observation & Science (EROS) Center

Address: 47914 252nd Street

City: Sioux Falls

State_or_Province: SD

Postal_Code: 57198-0001

Country: USA

Contact_Voice_Telephone: 605-594-6151

Contact_Voice_Telephone: 1-800-252-4547

Contact_TDD/TTY_Telephone: 605-594-6933

Contact_Facsimile_Telephone: 605-594-6589

Contact_Electronic_Mail_Address: custserv@usgs.gov

Hours_of_Service: 0800 - 1600 CT, M - F (-6h CST/-5h CDT GMT)

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Raster

Raster_Object_Information:

Raster_Object_Type: Pixel

Row_Count: 44337

Column_Count: 28072

Vertical_Count: 1

Spatial_Data_Organization_Information:

Indirect_Spatial_Reference: GRID

Direct_Spatial_Reference_Method: Raster

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name: State Plane Coordinate System

State_Plane_Coordinate_System:

SPCS_Zone_Identifier: 4400 (USGS), 5526 (ESRI)

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.99996

Longitude_of_Central_Meridian: -072.500000

Latitude_of_Projection_Origin: +42.500000

False_Easting: 0.001

False_Northing: 0.001

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Coordinate_Representation:

Abscissa_Resolution: 0.001

Ordinate_Resolution: 0.001

Planar_Distance_Units: Meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geodetic Reference System 80

Semi-major_Axis: 6378137

Denominator_of_Flattening_Ratio: 1 / 298.25722210

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988

Altitude_Resolution: 0.01

Altitude_Distance_Units: meters

Altitude_Encoding_Method:

Explicit elevation coordinate included with horizontal coordinates

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: vthydrodem

Attribute:

Attribute_Label: ObjectID

Attribute_Definition: Internal feature number.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain:

Sequential unique whole numbers that are automatically generated.

Attribute:

Attribute_Label: Value

Attribute_Value_Accuracy_Information:

Attribute_Value_Accuracy: NA

Attribute:

Attribute_Label: Count

Attribute_Definition_Source: Grid volume attribute table (VAT)

Overview_Description:

Entity_and_Attribute_Overview:

The single attribute of this Integer type grid is elevation in feet.

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: VT Center for Geographic Information

Contact_Address:

Address_Type: Mailing and Physical Address

Address: 1 National Life Dr, Dewey Building, 2nd Floor

City: Montpelier

State_or_Province: VT

Postal_Code: 05620-2001

Country: USA

Contact_Voice_Telephone: (802) 585-0820

Contact_TDD/TTY_Telephone: None

Contact_Facsimile_Telephone:

Contact_Electronic_Mail_Address: vcgi@vermont.gov

Hours_of_Service: 9am - 5pm, M-F

Resource_Description: ElevationOther_HILSHD10M

Distribution_Liability:

VCGI and the State of Vermont make no representations of any kind, including but not limited to the warranties of merchantability or fitness for a particular use, nor are any such warranties to be implied with respect to the data.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: ASC

Format_Specification: ESRI ASCII Grid format

Format_Information_Content: geospatial data

File_Decompression_Technique: ZIP extraction tool

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name:

https://maps.vcgi.vermont.gov/gisdata/vcgi/packaged_zips/ElevationOther_HILSH10M

Access_Instructions: Download from web site.

Offline_Option:

Offline_Media: USB drive

Fees:

No charge when downloading from the internet, and when no custom processing is required.

Ordering_Instructions: Send an email describing data request to vcgi@vermont.gov

Turnaround: About 5 days.

Custom_Order_Process: Send an email describing data request to vcgi@vermont.gov

Technical_Prerequisites: GIS Software

Available_Time_Period:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 20120210

Time_of_Day: Unknown

Metadata_Reference_Information:

Metadata_Date: 20120210

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: VT Center for Geographic Information

Contact_Person: GIS Database Administrator

Contact_Address:

Address_Type: Mailing and Physical Address

Address: 1 National Life Dr, Dewey Building, 2nd Floor

City: Montpelier

State_or_Province: VT

Postal_Code: 05620-2001

Country: USA

Contact_Voice_Telephone: (802) 585-0820

Contact_TDD/TTY_Telephone: None

Contact_Facsimile_Telephone:

Metadata_Standard_Name: FGDC Content Standards for Digital Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time

Metadata_Access_Constraints: None

Metadata_Use_Constraints: None

Metadata_Security_Information:

Metadata_Security_Classification_System: N/A

Metadata_Security_Classification: Unclassified

Metadata_Security_Handling_Description: No security considerations

Metadata_Extensions:

Online_Linkage: <http://ned.usgs.gov/NED/metadata.asp>

Profile_Name: National Elevation Dataset (NED) Metadata