Void filled SRTM Digital Elevation Model Quadrangles of Afghanistan, Projected in Geographic Coordinates

Metadata also available as

Metadata:

Identification_Information:

Citation:

Citation_Information:

Originator: USGS

Publication_Date: 2005

Publication_Time:

Title:

Void filled SRTM Digital Elevation Model Quadrangles of Afghanistan, Projected in Geographic Coordinates

Geospatial_Data_Presentation_Form: remote-sensing image

Series_Information:

Series_Name: USGS Data Series 130

Publication_Information:

Publication_Place: Reston, VA, USA

Publisher: USGS

Online_Linkage:

Description:

Abstract:

This SRTM digital elevation model DEM was produced for geologic mapping, natural resource investigations and reconstruction of Afghanistan under the USGS/USAID PASA agreement. The digital elevation model of Afghanistan contained in this file was produced from over 40 individual tiles of elevation data from the Shuttle Radar Topography Mission (SRTM). Each tile was downloaded, converted from its native Height file format (.hgt), and imported into ArcGIS for additional processing. Processing of the data included data gap filling, mosaicking, and re-projection of the tiles to form one single seamless digital elevation model (DEM).

Purpose:

The purpose of this data set is to provide a single consistent elevation model to be used for national scale mapping, GIS, remote sensing applications, and natural resource assessments for Afghanistan's reconstruction.

Time_Period_of_Content:

Time_Period_Information:

Multiple_Dates/Times:

Single_Date/Time:

Calendar_Date: February, 2000

Currentness_Reference: publication date

Status:

Progress: Complete

Maintenance_and_Update_Frequency: Irregular

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: 60.000000

East_Bounding_Coordinate: 75.000000

North_Bounding_Coordinate: 39.000000

South_Bounding_Coordinate: 29.000000

Keywords:

Theme:

Theme_Keyword_Thesaurus:

Theme_Keyword: DEM

Theme_Keyword: digital elevation model

Theme_Keyword: digital terrain model

Theme_Keyword: radar interferometry

Theme_Keyword: afghanistan

Access_Constraints: None

Use_Constraints: None

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Peter G. Chirico

Contact_Organization: US Geological Survey

Contact_Position: Geographer

Contact_Address:

Address_Type: mailing and physical address

Address: 12201 Sunrise Valley Drive

Address: National Center, MS926A

City: Reston

State_or_Province: VA

Postal_Code: 20192

Country: USA

Contact_Electronic_Mail_Address: pchirico@usgs.gov

Security_Information:

Security_Classification: Unclassified

Native_Data_Set_Environment:

Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 1; ESRI ArcCatalog 9.0.0.535

Data_Quality_Information:

Lineage:

Source_Information:

Source_Contribution:

Shuttle Radar Topography Mission elevation data augmented with elevation data developed from digitizing 1:200,000 scale contours (40, 80, and 160m contour interval) from Soviet Topographic maps.

Process_Step:

Process_Description:

For 11 days in February of 2000, NASA, the National Geospatial-Intelligence Agency (NGA), the German Aerospace Center (DLR), and the Italian Space Agency (ASI) flew X-band and C-band radar interferometry onboard the Space Shuttle Endeavor. The mission covered the Earth between 60ºN and 57ºS and will provide interferometric digital elevation models (DEMs) of approximately 80% of the Earth's land mass when processing is complete. The radar-pointing angle was approximately 55º at scene center. Ascending and descending orbital passes generated multiple interferometric data scenes for nearly all areas. Up to eight passes of data were merged to form the final processed SRTM DEMs. The effect of merging scenes averages elevation values recorded in coincident scenes and reduces, but does not completely eliminate the amount of area with layover and terrain shadow effects.

The most significant form of data processing for the Afghanistan DEM was gap-filling areas where the SRTM data contained a data void. These void areas are as a result of radar shadow, layover, standing water, and other effects of terrain as well as technical radar interferometry phase unwrapping issues. To fill these gaps, topographic contours were digitized from 1:200,000 scale Soviet General Staff Topographic Maps which date from the mid- late 1980's. Digital Contours were gridded to form elevation models for void areas and subsequently were merged with the SRTM data through GIS and image processing techniques.

Using PCI Geomatica Focus module's projection utility, the data was projected into Geographic, Decimal Degrees format. A shapefile, in the same projection, was used to delineate quadrangle boundaries to clip data from the countrywide dataset. The resulting clipped images were exported as .tif files.

Process_Date: 03/28/05

Process_Step:

Process_Description: Metadata imported.

Attribute Description:  NoData values have been assigned a value of -99.

 

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Raster

Raster_Object_Information:

Raster_Object_Type: Pixel

Row_Count: 1184

Column_Count: 2368

Vertical_Count: 1

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Geographic:

Geographic_Coordinate_Units: Decimal degrees

Planar:

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: row and column

Coordinate_Representation:

Abscissa_Resolution: 0.000845

Ordinate_Resolution: 0.000845

Geodetic_Model:

Horizontal_Datum_Name: D_WGS_1984

Ellipsoid_Name: WGS_1984

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257224

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: WGS84 (EGM96) Vertical Datum

Altitude_Distance_Units: Meters

Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: US Geological Survey

Contact_Address:

Address_Type: mailing and physical address

Address: 12201 Sunrise Valley Drive

Address: National Center, MS926A

City: Reston

State_or_Province: VA

Postal_Code: 20192

Country: USA

Resource_Description: Downloadable Data

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Transfer_Size: 10.699

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name: <http://gisdata.usgs.net/website/afghan/>

Offline_Option:

Offline_Media: DVD

Available_Time_Period:

Time_Period_Information:

Single_Date/Time:

Calendar_Date:

Metadata_Reference_Information:

Metadata_Date: 20050617

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: US Geological Survey

Contact_Person: Peter G. Chirico

Contact_Position: Geographer

Contact_Address:

Address_Type: mailing and physical address

Address: 12201 Sunrise Valley Drive

Address: National Center, MS926A

City: Reston

State_or_Province: VA

Postal_Code: 20192

Country: USA

Contact_Electronic_Mail_Address: pchirico@usgs.gov

Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time

Metadata_Extensions:

Profile_Name: ESRI Metadata Profile

Metadata_Extensions:

Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>

Profile_Name: ESRI Metadata Profile

Generated by mp version 2.8.6 on Fri Jun 17 11:50:30 2005