Significant topographic changes in the United States

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: U.S. Geological Survey

Publication_Date: November 2006

Title: Significant topographic changes in the United States

Geospatial_Data_Presentation_Form: vector digital data

Online_Linkage: <http://topochange.cr.usgs.gov/index.php>

Description:

Abstract:

The U.S. Geological Survey has developed a national inventory of significant topographic changes based on seamless multitemporal elevation data and land cover data. The National Elevation Dataset (NED) and the Shuttle Radar Topography Mission (SRTM) data form a unique pair of seamless elevation datasets that can be used to detect and analyze 20th century topographic surface changes in the United States. The primary types of topographic changes resulting from human geomorphic activity include surface mining, road construction, urban development, dam construction, and landfills.

Purpose:

The need for more comprehensive information on the nature and extent of recent human geomorphic activity led to a spatial emphasis for the first ever accounting of topographic change across the United States. Historical NED data values were subtracted from the recently collected SRTM data to determine significant topographic changes. The National Land Cover Dataset (NLCD) provided land cover information at a 30-meter resolution that matched the NED and SRTM data.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 1931

Ending_Date: 2000

Currentness_Reference: ground condition

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -127.403979

East_Bounding_Coordinate: -65.781197

North_Bounding_Coordinate: 51.197333

South_Bounding_Coordinate: 24.158520

Keywords:

Theme:

Theme_Keyword: elevation

Theme_Keyword: digital elevation model

Theme_Keyword: National Elevation Dataset

Theme_Keyword: NED

Theme_Keyword: Shuttle Radar Topography Mission

Theme_Keyword: SRTM

Theme_Keyword: topography

Theme_Keyword: topographic change

Theme_Keyword: change detection

Theme_Keyword: land change

Theme_Keyword: landscape change

Theme_Keyword: anthropogenic

Theme_Keyword: geomorphic change

Theme_Keyword: land transformation

Theme_Keyword: surface mining

Theme_Keyword: road construction

Theme_Keyword: urban development

Theme_Keyword: dam construction

Theme_Keyword: landfill

Theme_Keyword: reservoir construction

Theme_Keyword: land surface

Theme_Keyword: land cover change

Theme_Keyword: land use change

Theme_Keyword: human impacts

Place:

Place_Keyword: United States

Place_Keyword: CONUS

Access_Constraints:

Any acquisition or use of these data signifies a user's agreement to comprehension and compliance of the USGS Standard Disclaimer. Ensure all portions of metadata are read and clearly understood before using these data in order to protect both user and USGS interests. Please refer to <http://www.usgs.gov/privacy.html> for the USGS disclaimer.

Use_Constraints:

Although the USGS is making these data available to others who may find the data of value, USGS does not warrant, endorse, or recommend the use of these data for any given purpose. The user assumes the entire risk related to the use of these data. USGS is providing these data "as is", and USGS disclaims any and all warranties, whether expressed or implied, including (without limitation) any implied warranties of merchantability or fitness for a particular purpose. In no event will USGS be liable to you or to any third party for any direct, indirect, incidental, consequential, special, or exemplary damages or lost profits resulting from any use or misuse of these data. Acknowledgement of the U.S. Geological Survey would be appreciated in products derived from these data. Any user who modifies the data is obligated to describe the types of modifications they perform. User specifically agrees not to misrepresent the data, nor to imply that changes made were approved or endorsed by the USGS.

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Dean Gesch

Contact_Organization: U.S. Geological Survey

Contact_Position: Research physical scientist

Contact_Address:

Address_Type: mailing and physical address

Address: Earth Resources Observation and Science Center

Address: 47914 252nd Street

City: Sioux Falls

State_or_Province: South Dakota

Postal_Code: 57198-0001

Country: USA

Contact_Voice_Telephone: 605-594-6055

Contact_Facsimile_Telephone: 605-594-6529

Contact_Electronic_Mail_Address: gesch@usgs.gov

Browse_Graphic:

Browse_Graphic_File_Name: <http://topochange.cr.usgs.gov/results.php>

Data_Set_Credit: U.S. Geological Survey

Security_Information:

Security_Classification: Unclassified

Native_Data_Set_Environment:

Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.3.0.1770

Data_Quality_Information:

Positional_Accuracy:

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report:

National Elevation Dataset (NED) and Shuttle Radar Topography Mission (SRTM)

Quantitative_Vertical_Positional_Accuracy_Assessment:

Vertical_Positional_Accuracy_Value: 2.44 meters

Vertical_Positional_Accuracy_Explanation:

NED root mean square error (RMSE) vs. National Geodetic Survey control points (GPS on bench marks)

Quantitative_Vertical_Positional_Accuracy_Assessment:

Vertical_Positional_Accuracy_Value: 3.53 meters

Vertical_Positional_Accuracy_Explanation:

SRTM root mean square error (RMSE) vs. National Geodetic Survey control points (GPS on bench marks)

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator: U.S. Geological Survey

Publication_Date: June 2003

Title: National Elevation Dataset (NED)

Geospatial_Data_Presentation_Form: raster digital data

Other_Citation_Details:

Gesch, D.B., 2007, Chapter 4 - The National Elevation Dataset, in Maune, D., ed., Digital Elevation Model Technologies and Applications: The DEM Users Manual, 2nd Edition: Bethesda, Maryland, American Society for Photogrammetry and Remote Sensing, p. 99-118.

Online_Linkage: <http://ned.usgs.gov/index.asp>

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: June 2003

Source_Currentness_Reference: publication date

Source_Citation_Abbreviation: NED

Source_Contribution: U.S. Geological Survey

Source_Information:

Source_Citation:

Citation_Information:

Originator: National Geospatial-Intelligence Agency

Originator: NASA/JPL

Title: Shuttle Radar Topography Mission (SRTM)

Other_Citation_Details:

Farr, T.G., Rosen, P.A., Caro, E.; Crippen, R., Duren, R., Hensley, S., Kobrick, M., Paller, M., Rodriguez, E., Roth, L., Seal, D., Shaffer, S., Shimada, J., Umland, J., Werner, M., Oskin, M., Burbank, D., and Alsdorf, D., 2007, The Shuttle Radar Topography Mission: Reviews of Geophysics, 45, RG2004, doi:10.1029/2005RG000183.

Online_Linkage: <http://www2.jpl.nasa.gov/srtm/index.html>

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: February 2000

Source_Currentness_Reference: ground condition

Source_Citation_Abbreviation: SRTM

Source_Contribution:

National Geospatial-Intelligence Agency NASA/JPL

Source_Information:

Source_Citation:

Citation_Information:

Originator: U.S. Geological Survey

Publication_Date: 2001

Title: National Land Cover Dataset 1992 (NLCD)

Other_Citation_Details:

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., Wylie, B.K., and van Driel, N., 2001, Completion of the 1990s National Land Cover Dataset for the conterminous United States from Landsat Thematic Mapper data and ancillary data sources: Photogrammetric Engineering and Remote Sensing, v. 67, no. 6, p. 650-662.

Online_Linkage: <http://landcover.usgs.gov/natllandcover.php>

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 1992

Source_Currentness_Reference: ground condition

Source_Citation_Abbreviation: NLCD

Source_Contribution: U.S. Geological Survey

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: 8958

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Map_Projection:

Map_Projection_Name: Albers Conical Equal Area

Albers_Conical_Equal_Area:

Standard_Parallel: 29.500000

Standard_Parallel: 45.500000

Longitude_of_Central_Meridian: -96.000000

Latitude_of_Projection_Origin: 23.000000

False_Easting: 0.000000

False_Northing: 0.000000

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Coordinate_Representation:

Abscissa_Resolution: 0.000000

Ordinate_Resolution: 0.000000

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geodetic Reference System 80

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257222

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988

Altitude_Distance_Units: meters

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: topo_change_polygons

Attribute:

Attribute_Label: FID

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: Shape

Attribute_Definition: Feature geometry.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Coordinates defining the features.

Attribute:

Attribute_Label: AREA

Attribute_Definition: Area in square meters

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: square meters

Attribute:

Attribute_Label: PERIMETER

Attribute_Definition: Perimeter in meters

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: NUM_PIXEL

Attribute_Definition: Number of 1-arc-second pixels from NED and SRTM

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: count

Attribute:

Attribute_Label: NED_MIN

Attribute_Definition: NED minimum elevation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: NED_MAX

Attribute_Definition: NED maximum elevation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: NED_RANGE

Attribute_Definition:

NED range of elevations (max. elev. minus min. elev., or relief)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: NED_MEAN

Attribute_Definition: NED mean elevation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: NED_STDDEV

Attribute_Definition: NED elevation standard deviation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: NED_SUM

Attribute_Definition: NED sum of elevations

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: SRTM_MIN

Attribute_Definition: SRTM minimum elevation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: SRTM_MAX

Attribute_Definition: SRTM maximum elevation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: SRTM_RANGE

Attribute_Definition:

SRTM range of elevations (max. elev. minus min. elev., or relief)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: SRTM_MEAN

Attribute_Definition: SRTM mean elevation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: SRTM_STDDV

Attribute_Definition: SRTM elevation standard deviation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: SRTM_SUM

Attribute_Definition: SRTM sum of elevations

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: DIFF_MN_EL

Attribute_Definition: Difference in mean elevation (SRTM minus NED)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: PCTCHNG_EL

Attribute_Definition: Percent change in mean elevation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: percent

Attribute:

Attribute_Label: DIF_RELIEF

Attribute_Definition: Difference in relief (SRTM minus NED)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: PCTCHG_RLF

Attribute_Definition: Percent change in relief

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: percent

Attribute:

Attribute_Label: NLCD_CLASS

Attribute_Definition: Land cover class number (from NLCD)

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NLCD land cover class definitions

Codeset_Source: <http://landcover.usgs.gov/classes.php>

Attribute:

Attribute_Label: N_SLP_MIN

Attribute_Definition: NED minimum slope

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: N_SLP_MAX

Attribute_Definition: NED maximum slope

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: N_SLP_RNGE

Attribute_Definition: NED range of slopes (max. slope minus min. slope)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: N_SLP_MEAN

Attribute_Definition: NED mean slope

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: N_SLP_STDV

Attribute_Definition: NED slope standard deviation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: S_SLP_MIN

Attribute_Definition: SRTM minimum slope

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: S_SLP_MAX

Attribute_Definition: SRTM maximum slope

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: S_SLP_RNGE

Attribute_Definition: SRTM range of slopes (max. slope minus min. slope)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: S_SLP_MEAN

Attribute_Definition: SRTM mean slope

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: S_SLP_STDV

Attribute_Definition: SRTM slope standard deviation

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: NED_ASP_MD

Attribute_Definition: NED median aspect

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees (clockwise from north)

Attribute:

Attribute_Label: SRTM_ASPMD

Attribute_Definition: SRTM median aspect

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees (clockwise from north)

Attribute:

Attribute_Label: SUM_DIFF

Attribute_Definition: Sum of elevation differences (SRTM minus NED)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: meters

Attribute:

Attribute_Label: DIF_MN_SLP

Attribute_Definition: Difference in mean slope (SRTM minus NED)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees

Attribute:

Attribute_Label: CHNG_TYPE

Attribute_Definition: Topographic change type

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: Cut

Enumerated_Domain_Value_Definition: Decrease in elevation (removal of material)

Enumerated_Domain:

Enumerated_Domain_Value: Fill

Enumerated_Domain_Value_Definition: Increase in elevation (addition of material)

Attribute:

Attribute_Label: MINE_BUFFR

Attribute_Definition: Proximity to surface mine

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: Mine

Enumerated_Domain_Value_Definition:

Mapped surface mine (majority land cover class number 32 from NLCD)

Enumerated_Domain_Value_Definition_Source: <http://landcover.usgs.gov/classes.php>

Enumerated_Domain:

Enumerated_Domain_Value: Yes

Enumerated_Domain_Value_Definition:

Within a 500 meter buffer of another topographic change polygon that is located on a mapped mine location in the NLCD

Enumerated_Domain:

Enumerated_Domain_Value: No

Enumerated_Domain_Value_Definition:

Not within a 500 meter buffer of another topographic change polygon that is located on a mapped mine location in the NLCD

Attribute:

Attribute_Label: RESOLUTION

Attribute_Definition: Resolution of the NED source data

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NED Data Dictionary

Codeset_Source:

<http://ned.usgs.gov/downloads/documents/NED_DataDictionary2006.pdf>

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 3

Enumerated_Domain_Value_Definition: 3 arc-seconds (approximately 90 meters)

Enumerated_Domain:

Enumerated_Domain_Value: 10

Enumerated_Domain_Value_Definition: 10 meters

Enumerated_Domain:

Enumerated_Domain_Value: 13

Enumerated_Domain_Value_Definition: 1/3 arc-second (approximately 10 meters)

Enumerated_Domain:

Enumerated_Domain_Value: 30

Enumerated_Domain_Value_Definition: 30 meters

Attribute:

Attribute_Label: PDEVICE

Attribute_Definition: Production device for the NED source data

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NED Data Dictionary

Codeset_Source:

<http://ned.usgs.gov/downloads/documents/NED_DataDictionary2006.pdf>

Attribute:

Attribute_Label: PMETHOD

Attribute_Definition: Production method for the NED source data

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NED Data Dictionary

Codeset_Source:

<http://ned.usgs.gov/downloads/documents/NED_DataDictionary2006.pdf>

Attribute:

Attribute_Label: S_DATE

Attribute_Definition:

Date of the original aerial photography, survey data, or map for the NED source data

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NED Data Dictionary

Codeset_Source:

<http://ned.usgs.gov/downloads/documents/NED_DataDictionary2006.pdf>

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: year (format is either YYYY or YYMM)

Attribute:

Attribute_Label: I_DATE

Attribute_Definition: Inspection (production) date for the NED source data

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NED Data Dictionary

Codeset_Source:

<http://ned.usgs.gov/downloads/documents/NED_DataDictionary2006.pdf>

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: year (format is either YYYY or YYMM)

Attribute:

Attribute_Label: QUADDATE

Attribute_Definition:

Date on which the NED source data was first processed into the NED

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NED Data Dictionary

Codeset_Source:

<http://ned.usgs.gov/downloads/documents/NED_DataDictionary2006.pdf>

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: year (format: YYYYMMDD)

Attribute:

Attribute_Label: QUADNAME

Attribute_Definition:

Name of the USGS 7.5-minute (1:24,000-scale) topographic quadrangle map associated with the NED source data

Attribute_Domain_Values:

Codeset_Domain:

Codeset_Name: NED Data Dictionary

Codeset_Source:

<http://ned.usgs.gov/downloads/documents/NED_DataDictionary2006.pdf>

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: text (format: place_name_ST)

Attribute:

Attribute_Label: DIF_MD_ASP

Attribute_Definition: Difference in median aspect (SRTM minus NED)

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: degrees (clockwise from north)

Attribute:

Attribute_Label: VOLUME_M3

Attribute_Definition: Volume of material removed or deposited in topographic change

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: negative value = "cut" (decreased elevation; material removed)

Enumerated_Domain_Value_Definition: cubic meters

Enumerated_Domain:

Enumerated_Domain_Value:

positive value = "fill" (increased elevation; material deposited)

Enumerated_Domain_Value_Definition: cubic meters

Attribute:

Attribute_Label: ABS_VOL_M3

Attribute_Definition:

Absolute value of volume of material removed or deposited in topographic change

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: cubic meters

Attribute:

Attribute_Label: AREA_SQ_KM

Attribute_Definition: Area in square kilometers

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: square kilometers

Attribute:

Attribute_Label: AREA_SQ_MI

Attribute_Definition: Area in square miles

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: square miles

Attribute:

Attribute_Label: AREA_ACRES

Attribute_Definition: Area in acres

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: acres

Attribute:

Attribute_Label: AREA_HECT

Attribute_Definition: Area in hectares

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition: hectares

Attribute:

Attribute_Label: VOLAREA_RT

Attribute_Definition: Volume-area ratio

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value_Definition:

Ratio of topographic change volume (cubic meters) to polygon area (square meters)

Overview_Description:

Entity_and_Attribute_Overview:

This dataset contains a total of 8,958 polygons. Of this total, 3,103 polygons represent "holes" in other polygons, and these hole polygons have all attributes with a value of zero or a blank. This leaves 5,855 polygons that delineate the areas of significant topographic changes in the conterminous United States, and these polygons have valid attribute values. The number of distinct areas of topographic change is 5,263, but some of these areas cross topographic quadrangle map boundaries. The polygons that cross map boundaries were split into two (or more) adjoining polygons so that the unique attributes of the map-based DEMs could be retained and attached to the topographic change polygons. This splitting and attributing procedure resulted in 592 additional polygons, thus the total of 5,855 features in this dataset (as compared to the number of 5,263 features in the original topographic change polygon dataset). Note that the following attributes refer to each of the individual 5,855 polygons (including those split along quad map boundaries): FID, AREA, PERIMETER, RESOLUTION, PDEVICE, PMETHOD, S_DATE, I_DATE, QUADDATE, and QUADNAME. All other attributes refer to the values for the original 5,263 distinct topographic change area polygons before any splitting along quad map boundaries. Thus, for those adjoining polygons along quad map boundaries, all attributes except those listed above have the identical values as the adjacent polygon.

Distribution_Information:

Distributor:

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)

Contact_Instructions:

The above is the contact information for the USGS Earth Resources Observation & Science (EROS) Center in Sioux Falls, SD. This is a digital data storage and distribution center for the USGS.

Resource_Description: Downloadable Data

Distribution_Liability:

The U.S. Geological Survey gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from a USGS server and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the utility of the data on another system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Transfer_Size: 9.861

Metadata_Reference_Information:

Metadata_Date: 20090423

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Dean Gesch

Contact_Organization: U.S. Geological Survey

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: 605-594-6055

Contact_Electronic_Mail_Address: gesch@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_Security_Information:

Metadata_Security_Classification: Unclassified

Metadata_Extensions:

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

Profile_Name: ESRI Metadata Profile