srtm30plus-world_pctshade.tif - SRTM30PLUS color encoded shaded relief world topography (approximately 4km) GeoTIFF image

Metadata also available as: FAQ | TEXT

Metadata:

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

Identification_Information:

Citation:

Citation_Information:

Originator: Valerie Paskevich

Publication_Date: 200508

Title:

srtm30plus-world_pctshade.tif - SRTM30PLUS color encoded shaded relief world topography (approximately 4km) GeoTIFF image

Edition: 1.0

Geospatial_Data_Presentation_Form: remote-sensing image

Series_Information:

Series_Name: Open-File Report

Issue_Identification: 2005-1001

Publication_Information:

Publication_Place: Woods Hole Science Center, Woods Hole, MA

Publisher: U.S. Geological Survey, Coastal and Marine Geology Program

Online_Linkage:

<http://pubs.usgs.gov/of/2005/1001/data/basemaps/srtm30plus/srtm30plus-world_pctshade.zip>

Online_Linkage: <http://pubs.usgs.gov/of/2005/1001/htmldocs/datacatalog.htm>

Larger_Work_Citation:

Citation_Information:

Originator: L.J. Poppe

Originator: S.J. Williams

Originator: V.F. Paskevich

Publication_Date: 2005

Title:

U.S. Geological Survey East-Coast Sediment Analysis: Procedures, Database, and GIS Data

Edition: 1.0

Series_Information:

Series_Name: Open-File Report

Issue_Identification: 2005-1001

Publication_Information:

Publication_Place: Woods Hole Science Center, Woods Hole, MA

Publisher: U.S. Geological Survey, Coastal and Marine Geology Program

Other_Citation_Details:

Publication and data are released via DVD-ROM media. This digital publication may also be available via the web at pubs.usgs.gov

Online_Linkage: <http://pubs.usgs.gov/of/2005/1001/>

Description:

Abstract:

Joseph J. Becker and David T. Sandwell at the Scripps Oceanographic Institute have generated a dataset of world-wide coverage combining NASA's Shuttle Radar Topography Mission (SRTM) obtained elevation data and Smith and Sandwell global 2-minute bathymetry. This data set provides a global composite of elevation that can be utilized to create elevation/bathymetry visualization.

The Shuttle Radar Topography Mission is a collaborative project between NASA, the National Imagery and Mapping Agency (NIMA), and the German and Italian space agencies to map the elevation of a large part of the globe. SRTM consisted of a specially modified radar system that flew onboard the Space Shuttle Endeavour during an 11-day mission in February of 2000. The instrument operated virtually flawlessly and imaged 99.96% of the targeted landmass at least one time, 94.59% at least twice and about 50% at least three or more times. The goal was to image each terrain segment at least twice from different angles (on ascending, or north-going, and descending orbit passes) to fill in areas shadowed from the radar beam by terrain. The 'targeted landmass' consisted of all land between 56 degrees south and 60 degrees north latitude, which comprises almost exactly 80% of the total landmass.

While SRTM30 has the same resolution as GTOPO30, it can be considered a more accurate global digital data set compared to GTOPO30 because of its seamless and uniform representation, due to the fact that it was created over a short period of time from a single source rather than from the numerous sources spanning many decades that went into creating the GTOPO30 data set.

This data set does not provide the high resolution SRTM elevation of the original one degree datasets. Sample spacing for the original individual data points is either 1 arc-second or 3 arc-seconds, referred to as SRTM-1 and SRTM-3, respectively. The user may visit <ftp://e0mss21u.ecs.nasa.gov/srtm/> or <ftp://e0mss21u.ecs.nasa.gov/srtm/> to obtain the higher resolution datasets.

Purpose:

This image provides a broad scale view of the world topography (elevation and bathymetry) on which other Geographic Information System (GIS) data layers may be co-located and viewed.

These data are intended for science researchers, students, policy makers, and the general public. The data can be used with geographic informations ystems (GIS) software to display geologic and oceanographic information.

Supplemental_Information:

While SRTM30 has the same resolution as GTOPO30, it can be considered a more accurate global digital data set compared to GTOPO30 because of its seamless and uniform representation, due to the fact that it was created over a short period of time from a single source rather than from the numerous sources spanning many decades that went into creating the GTOPO30 data set. However, it must be noted that the SRTM30 does not cover the poles north and south of approximately 60° latitude. Therefore, data for Antarctica, for example, must be obtained from the GTOPO30 data set.

Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 2005

Currentness_Reference: publication date

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -180

East_Bounding_Coordinate: 180

North_Bounding_Coordinate: 90

South_Bounding_Coordinate: -90

Keywords:

Theme:

Theme_Keyword_Thesaurus: General

Theme_Keyword: U.S. Geological Survey

Theme_Keyword: USGS

Theme_Keyword: Coastal and Marine Geology Program

Theme_Keyword: CMGP

Theme_Keyword: Woods Hole Science Center

Theme_Keyword: WHSC

Theme_Keyword: GeoTIFF image

Theme_Keyword: color-encoded shaded relief

Theme_Keyword: bathymetry

Theme_Keyword: topography

Theme_Keyword: SRTM30_PLUS

Theme_Keyword: Shuttle Radar Topography Mission

Theme:

Theme_Keyword_Thesaurus: ISO 19115 Topic Category

Theme_Keyword: oceans and estuaries

Theme_Keyword: elevation

Theme_Keyword: imageryBaseMapsEarthCover

Place:

Place_Keyword_Thesaurus: General

Place_Keyword: world

Access_Constraints: None

Use_Constraints:

Bathymetry is not to be used for navigational purposes.

Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the source of this information.

All source data are derived from public domain sources and these data are also in the public domain.

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Browse_Graphic:

Browse_Graphic_File_Name:

<http://pubs.usgs.gov/of/2005/1001/data/basemaps/srtm30plus/srtm30plus-world_pctshade-thumb.gif>

Browse_Graphic_File_Description: Thumbnail image showing overview and extent of data layer.

Browse_Graphic_File_Type: GIF

Browse_Graphic:

Browse_Graphic_File_Name:

<http://pubs.usgs.gov/of/2005/1001/data/basemaps/srtm30plus/srtm30plus-world_pctshade.gif>

Browse_Graphic_File_Description: Image showing extent and coverage of data layer.

Browse_Graphic_File_Type: GIF

Data_Set_Credit:

Please credit Joseph J. Becker, David T. Sandwell for the compilation of the Land and Ocean data used as the source.

Native_Data_Set_Environment:

Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.0.0.535

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

Elevation Data - Each SRTM data tile contains a mosaic of elevations generated by averaging all data takes that fall within that tile. Since the primary error source in synthetic aperture radar data is speckle, which has the characteristics of random noise, combining data through averaging reduces the error by the square root of the number of data takes used. In the case of SRTM the number of data takes could range from a minimum of one (in a very few cases) up to as many as ten or more.

Completeness_Report:

Land data are based on the 1-km averages of topography derived from the USGS SRTM30 grided DEM data product created with data from the NASA Shuttle Radar Topography Mission. GTOPO30 data are used for high latitudes where SRTM data are not available. Ocean data are based on the Smith and Sandwell global 2-minute grid between latitudes +/- 72 degrees. Higher resolution grids have been added from the LDEO Ridge Multibeam Synthesis Project and the NGDC Coastal Relief Model. Arctic bathymetry is from the International Bathymetric Chart of the Oceans (IBCAO) [Jakobsson et al., 2003].

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Quantitative_Horizontal_Positional_Accuracy_Assessment:

Horizontal_Positional_Accuracy_Value: 20 meters

Horizontal_Positional_Accuracy_Explanation: circular error at 90% confidence

Vertical_Positional_Accuracy:

Quantitative_Vertical_Positional_Accuracy_Assessment:

Vertical_Positional_Accuracy_Value: 16 meters

Vertical_Positional_Accuracy_Explanation: linear error at 90% confidence

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator: Joseph J. Becker

Originator: David T. Sandwell

Publication_Date: 200412

Title:

SRTM30_PLUS: SRTM30, Coastal and Ridge Multibeam, Estimated Topography

Edition: 0.1

Geospatial_Data_Presentation_Form: document

Publication_Information:

Publication_Place: La Jolla, CA

Publisher:

Scripps Institution of Oceanography, University of California San Diego

Online_Linkage: <http://topex.ucsd.edu/WWW_html/srtm30_plus.html>

Source_Scale_Denominator: 1:1000

Type_of_Source_Media: disc

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 200412

Source_Currentness_Reference: publication date

Source_Citation_Abbreviation: srtm30plus

Source_Contribution:

This data consists of 33 files binary of global topography (elevation & bathymetry; 16-bit signed values). The individual files were downloaded via the web and combined to create a single raster coverage of world coverage. The grid resolution of the source data is 30 second which is roughly one kilometer.

Process_Step:

Process_Description:

Thirty-three zip archive files of global topography were downloaded. The files were unzipped to create raw 16-bit binary data files. Each of the thirty-three files were imported into a separate PCI Geomatics database file. Importing the files into PCI allowed the ability to swap the bytes from a 16-bit Most-Significant-Bit order (MSB: Sun/Motorola) to a 16-bit Least-Significant-Bit order (LSB: Intel/VAX). Georeferencing information were added to each of the thirty-three files.

Process_Date: 20050502

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Process_Step:

Process_Description:

A new PCI Geomatics database file was defined to combine the global dataset. The individual thirty-three files were mosaiced to create on world view.

Process_Date: 20050502

Source_Produced_Citation_Abbreviation: srtm30plus.pix

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Process_Step:

Process_Description:

The original composite image was sub-sampled to reduce the image size and resolution. The original, full bounds of the image were retained but the image pixel size was reduced from .008333 (approx 1km) to .033333 (approx 4km). Bi-Linear sampling was applied to smooth possible artificats in the data.

Source_Used_Citation_Abbreviation: srtm30plus.pix

Process_Date: 20050508

Source_Produced_Citation_Abbreviation: srtm30plus-4km.pix

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Process_Step:

Process_Description:

Two additional 8-bit channel were added to the PCI database and the program REL was run to create an 8-bit shaded relief image.

Source_Used_Citation_Abbreviation: srtm30plus-4km.pix

Process_Date: 20050508

Source_Produced_Citation_Abbreviation: srtm30plus-4km.pix

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Process_Step:

Process_Description:

The shaded relief image was viewed in PCI Imageworks. A linear stretch enhancement was applied to the image and the resulting Look-up Table (LUT) saved in the database.

Source_Used_Citation_Abbreviation: srtm30plus-4km.pix

Process_Date: 20050508

Source_Produced_Citation_Abbreviation: srtm30plus-4km.pix

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Process_Step:

Process_Description:

The 8-bit shaded relief image had a linear stretch permanently applied to create a new, final image.

Source_Used_Citation_Abbreviation: srtm30plus-4km.pix

Process_Date: 20050508

Source_Produced_Citation_Abbreviation: srtm30plus-4km.pix

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Process_Step:

Process_Description:

The final 8-bit grey-scale, shaded relief image was exported to a GeoTIFF image

Source_Used_Citation_Abbreviation: srtm30plus-4km.pix

Process_Date: 20050508

Source_Produced_Citation_Abbreviation: srtm30plus-4km_shade.tif

Source_Produced_Citation_Abbreviation: srtm30plus-4km_shade.tfw

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Process_Step:

Process_Description:

The two source images were brought into Corel PhotoPaint. The color-encoded elevation image (strm30plus-4km_color.tif) was overlaid ontop of the shaded relief image (srtm30plus-4km_shade.tif). The color image was made 60% transparent to allow shading to be seen through the image. The two images were combined to create a single 24-bit image showing elevation based on color.

Source_Used_Citation_Abbreviation: srtm30plus-4km_shade.tif

Source_Used_Citation_Abbreviation: srtm30plus-4km_color.tif

Process_Date: 20050509

Source_Produced_Citation_Abbreviation: srtm30plus-world_pctshade.tif

Source_Produced_Citation_Abbreviation: srtm30plus-world_pctshade.tfw

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@usgs.gov

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Raster

Raster_Object_Information:

Raster_Object_Type: Pixel

Row_Count: 10804

Column_Count: 18001

Vertical_Count: 1

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Geographic:

Latitude_Resolution: 0.033333

Longitude_Resolution: 0.033333

Geographic_Coordinate_Units: Decimal degrees

Planar:

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: row and column

Coordinate_Representation:

Abscissa_Resolution: 0.033333

Ordinate_Resolution: 0.033333

Geodetic_Model:

Horizontal_Datum_Name: D_WGS_1984

Ellipsoid_Name: WGS_1984

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257224

Entity_and_Attribute_Information:

Overview_Description:

Entity_and_Attribute_Overview: There are no attributes associated with the GEOTIFF image.

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: U.S. Geological Survey

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700

Contact_Facsimile_Telephone: (508) 457-2310

Resource_Description: Downloadable Data

Distribution_Liability:

Although this data set has been used by the U.S. Geological Survey (USGS), no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and/or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Trade, firm, or product names and other references to non-USGS products and services are provided for information only and do not constitute endorsement or warranty, express or implied, by the USGS, USDOI, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: TIFF

Format_Specification: GeoTIFF image

Format_Information_Content: Archive containing GeoTIFF image, world file and metadata.

File_Decompression_Technique: zip

Transfer_Size: 0.000

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name:

<http://pubs.usgs.gov/of/2005/1001/data/basemaps/srtm30plus/srtm30plus-world_pctshade.zip>

Access_Instructions: Data are downloadable via the World Wide Web (WWW).

Offline_Option:

Offline_Media: DVD-ROM

Recording_Capacity:

Recording_Density: 4.75

Recording_Density_Units: Gbytes

Recording_Format: UDF

Fees: None

Technical_Prerequisites:

This image is available as a GEOTIFF image with an accompanying world file. To utilize this data, the user must have an image viewer, image processing or GIS software package capable of importing a GeoTIFF image.

Metadata_Reference_Information:

Metadata_Date: 20050511

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Valerie Paskevich

Contact_Organization: U.S. Geological Survey

Contact_Position: Information Specialist, GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2281

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: vpaskevich@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_Access_Constraints: None

Metadata_Use_Constraints: None

Metadata_Extensions:

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

Profile_Name: ESRI Metadata Profile