# NLCD 2001 Percent Developed Imperviousness for Alaska, Zone AK08, by State: NLCD2001_IMP_Alaska

Metadata also available as

# 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: 20150115
      Title:
        NLCD 2001 Percent Developed Imperviousness for Alaska, Zone AK08, by State: NLCD2001_IMP_Alaska
      Edition: 1.0
      Geospatial_Data_Presentation_Form: remote-sensing image
      Series_Information:
        Series_Name: None
        Issue_Identification: None
      Publication_Information:
        Publication_Place: Sioux Falls, SD
        Publisher: U.S. Geological Survey
      Other_Citation_Details:
        References: Yang, L, C. Huang, C. Homer, B. Wylie, and M. Coan, 2002. An approach for mapping large-area impervious surfaces: Synergistic use of Landsat 7 ETM+ and high spatial resolution imagery. Canadian Journal of Remote Sensing, 29: 2, 230-240. Homer, C., C. Huang, L. Yang, B. Wylie and M. Coan, 2004. Development of a 2001 national land cover database for the United States. Photogrammetric Engineering and Remote Sensing. The USGS acknowledges the support of MDA Federal Inc. in development of data in this zone.
      Online_Linkage:
        <http://gisdata.usgs.gov/tdds/downloadfile.php?TYPE=nlcd2001_imp_state&ORIG=META&FNAME=NLCD2001_IMP_Alaska.zip>
      Online_Linkage:
        <http://tdds.cr.usgs.gov/metadata/nlcd/2001/impervious/states/NLCD2001_IMP_Alaska.htm>
      Online_Linkage: <http://nationalmap.gov/viewer.html>
  Description:
    Abstract:
      The National Land Cover Database 2001 Percent Developed Imperviousness for mapping zone ak08 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of federal agencies (www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (EPA), the U.S. Department of Agriculture - Forest Service (USDA-FS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (FWS), the Bureau of Land Management (BLM) and the USDA Natural Resources Conservation Service (NRCS). One of the primary goals of the project is to generate a current, consistent, seamless, and accurate National Land Cover Database (NLCD) circa 2001 for the United States at medium spatial resolution. For a detailed definition and discussion on MRLC and the NLCD 2001 products, refer to Homer et al. (2003) and <http://www.mrlc.gov/mrlc2k.asp>. The NLCD 2001 is created by partitioning the U.S. into mapping zones. A total of 66 mapping zones within the conterminous U.S., with an additional 12 in Alaska, were delineated based on ecoregion and geographical characteristics, edge matching features and the size requirement of Landsat mosaics. Mapping zone ak08 encompasses a portion of Alaska. Questions about the NLCD mapping zone ak08 can be directed to the NLCD 2001 land cover mapping team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.
    Purpose:
      The goal of this project is to provide the Nation with complete, current and consistent public domain information on its land use and land cover.
    Supplemental_Information:
      Corner Coordinates (center of pixel, projection meters) Upper Left Corner: 87645.000000 meters(X), 1460235.000000 meters(Y) Lower Right Corner: 300435.000000 meters(X), 1055955.000000 meters(Y)
  Time_Period_of_Content:
    Time_Period_Information:
      Range_of_Dates/Times:
        Beginning_Date: 20000816
        Ending_Date: 20030810
    Currentness_Reference: ground condition
  Status:
    Progress: Complete
    Maintenance_and_Update_Frequency: As needed
  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate: -179.133392334478
      East_Bounding_Coordinate: 179.788208007507
      North_Bounding_Coordinate: 71.3980484011132
      South_Bounding_Coordinate: 51.2172393799589
  Keywords:
    Theme:
      Theme_Keyword_Thesaurus: NGDA Portfolio Themes
      Theme_Keyword: NGDA
      Theme_Keyword: National Geospatial Data Asset
      Theme_Keyword: Land Use Land Cover Theme
    Theme:
      Theme_Keyword_Thesaurus: None
      Theme_Keyword: Imperviousness
      Theme_Keyword: GIS
      Theme_Keyword: U.S. Geological Survey
      Theme_Keyword: USGS
      Theme_Keyword: digital spatial data
    Theme:
      Theme_Keyword_Thesaurus: ISO 19115 Topic Category
      Theme_Keyword: imageryBaseMapsEarthCover
      Theme_Keyword: 010
    Place:
      Place_Keyword_Thesaurus:
        U.S. Department of Commerce, 1995, Countries, dependencies, areas of special sovereignty, and their principal administrative divisions, Federal Information Processing Standard 10-4,): Washington, D.C., National Institute of Standards and Technology
      Place_Keyword: United States
      Place_Keyword: U.S.
      Place_Keyword: US
    Place:
      Place_Keyword_Thesaurus: None
      Place_Keyword: zone ak08
    Place:
      Place_Keyword_Thesaurus:
        U.S. Department of Commerce, 1987, Codes for the identification of the States, the District of Columbia and the outlying areas of the United States, and associated areas (Federal Information Processing Standard 5-2): Washington, D.C., National Institute of Standards and Technology
      Place_Keyword: AK
    Place:
      Place_Keyword_Thesaurus: Geographic Names Information System
      Place_Keyword: Alaska
  Access_Constraints: None
  Use_Constraints: None
  Point_of_Contact:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization: U.S. Geological Survey
      Contact_Position: Customer Services Representative
      Contact_Address:
        Address_Type: mailing and physical
        Address: USGS EROS
        Address: 47914 252nd Street
        City: Sioux Falls
        State_or_Province: SD
        Postal_Code: 57198-0001
        Country: USA
      Contact_Voice_Telephone: 605/594-6151
      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 USGS point of contact is for questions relating to the data display and download from this web site. For questions regarding data content and quality, refer to: <http://www.mrlc.gov/mrlc2k.asp> or email: mrlc@usgs.gov
  Browse_Graphic:
    Browse_Graphic_File_Name:
      <http://tdds.cr.usgs.gov/browse/nlcd/2001/impervious/states/NLCD2001_IMP_Alaska.jpg>
    Browse_Graphic_File_Description: Tiled NLCD Browse Image
    Browse_Graphic_File_Type: JPEG
  Data_Set_Credit: U.S. Geological Survey, MDA Federal Inc.
  Security_Information:
    Security_Classification_System: None
    Security_Classification: Unclassified
    Security_Handling_Description: N/A
  Native_Data_Set_Environment:
    Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 1; ESRI ArcCatalog 9.0.0.535

Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report:
      The information on data quality for mapping zone ak08 was generated by the Regression Tree algorithm that conducts a cross-validation for assessing classification and prediction reliability. No formal independent accuracy assessment of mapping zone ak08 imperviousness has been made. The regression tree algorithm employed in NLCD 2001 mapping offers a cross-validation option for assessing classification and prediction reliability. Cross-validation can provide relatively reliable estimates for imperviousness predictions if the reference data used for cross-validation are collected based on a statistically valid sampling design. For mapping zone ak08 imperviousness modeling, a 5-fold cross-validation was conducted by dividing the entire training data set into 5 subsets of equal size. For each model run, an accuracy estimate was derived using one subset to evaluate the model prediction (with the model developed using the remaining training samples). This process was repeated 5 times. After all 5 runs, an average value of all accuracy estimates from the 5 runs was computed. Users should be cautioned that these cross-validation results provide users with only first-order estimates of data quality, and should not be considered a formal accuracy assessment.
    Quantitative_Attribute_Accuracy_Assessment:
      Attribute_Accuracy_Value: 89.7
      Attribute_Accuracy_Explanation:
        The above listed value is the overall accuracy obtained for imperviousness data in the cross-validation study for mapping zone ak08.
  Logical_Consistency_Report:
    The method employed to map percent developed imperviousness for NLCD 2001 mapping zone ak08 consists of three key steps: deriving reference data of imperviousness from the high spatial resolution images, calibrating density prediction models using reference data and Landsat spectral bands, and extrapolating the developed models spatially to map per-pixel imperviousness.
  Completeness_Report:
    This NLCD product of mapping zone ak08 Imperviousness layer is the version dated January 15, 2015.
  Positional_Accuracy:
    Horizontal_Positional_Accuracy:
      Horizontal_Positional_Accuracy_Report: N/A
    Vertical_Positional_Accuracy:
      Vertical_Positional_Accuracy_Report: N/A
  Lineage:
    Process_Step:
      Process_Description:
        The method employed to map percent imperviousness for NLCD 2001 mapping zone ak08 consists of three key steps: deriving reference data of imperviousness from the high spatial resolution images, calibrating density prediction models using reference data and Landsat spectral bands, and extrapolating the developed models spatially to map per-pixel imperviousness. This method is described in detail in Yang et al. (2003). This method was applied to mapping zone ak08 by MDA Federal Inc.
      Source_Used_Citation_Abbreviation: Landsat ETM, DOQQ, USGS/EROS
      Process_Date: Unknown
      Source_Produced_Citation_Abbreviation: USGS NLCD
      Process_Contact:
        Contact_Information:
          Contact_Organization_Primary:
            Contact_Organization: MDA Federal Inc.
            Contact_Person: David Cunningham
          Contact_Position: Vice President, Environmental/GIS Services
          Contact_Address:
            Address_Type: mailing
            Address: 6011 Executive Blvd., Suite 400
            City: Rockville
            State_or_Province: MD
            Postal_Code: 20852
            Country: USA
          Contact_Voice_Telephone: 240-833-8200
          Contact_Facsimile_Telephone: 240-833-8201
          Contact_Electronic_Mail_Address: dcunningham@earthsat.com
          Hours_of_Service: 8.00. a.m. - 5.00. P.M. ET M-F
    Process_Step:
      Process_Description:
        To develop adequate training data for impervious estimation, 8 DOQQ's across the mapping zone with a nominal spatial resolution of 1-m were classified into either pervious or non-pervious surfaces, and then summed within each 30 meter Landsat pixel cell to obtain percentage of imperviousness. Training data were selected based on the degree of variance each training data set possesses with regards to Landsat ETM+ imagery used for mapping. Each added training data set decreased the amount of variance present within the Landsat data as a whole. The selection process was repeated until the amount of variance explained reached a pre-defined threshold. By combining the training data with Landsat spectral data and other ancillary data, percent imperviousness prediction models were developed using a regression tree algorithm (named "Cubist"). All data layers used as input for running the Cubist in order to establish the prediction model for imperviousness are listed in the "Supplemental Information" section. Three ancillary data sets were used for urban/suburban delineation masking, which is essential to confine the imperviousness mapping within the developed areas. After the best combination of possible input data layers had been determined and the final percent impervious layer produced, the urban mask created was used to eliminate those pixels from the final percent impervious file that fall outside identified impervious surface areas. Thus, the impervious pixels identified within the mask were retained, while all non-impervious surface pixels were removed from the final product. This corrected for any small areas of pixels that may have been included as part of the impervious surface layer because their spectral signature was not covered in the Cubist modeling process. Finally, visual inspection of imperviousness layer was made with limited manual editing to eliminate non-urban areas based on area of interest delineated by the mapping team. Acquisition dates of Landsat ETM+ (TM) scenes used for land cover classification in zone ak08 are as follows: LEAF ON1 (Summer)- Index 2 for Path 69/Row 16 on 07/30/2002 = Scene_ID 7069016000221150 Index 2 for Path 69/Row 17 on 07/30/2002 = Scene_ID 7069017000221150 Index 3 for Path 69/Row 17 on 08/10/2003 = Scene_ID 5069017000322210 Index 2 for Path 69/Row 18 on 07/30/2002 = Scene_ID 7069018000221150 Index 4 for Path 69/Row 18 on 06/25/2001 = Scene_ID 7069018000117650 Index 1 for Path 70/Row 16 on 08/16/2000 = Scene_ID 7070016000022950 Index 1 for Path 70/Row 17 on 08/16/2000 = Scene_ID 7070017000022950 LEAF ON2 (Summer) - Index 1 for Path 69/Row 16 on 09/29/2001 = Scene_ID 7069016000127250 Index 1 for Path 69/Row 17 on 09/29/2001 = Scene_ID 7069017000127250 Index 1 for Path 69/Row 18 on 09/29/2001 = Scene_ID 7069018000127250 Index 2 for Path 70/Row 16 on 09/17/2000 = Scene_ID 7070016000026151 Index 2 for Path 70/Row 17 on 09/17/2000 = Scene_ID 7070017000026151 Landsat data and ancillary data used for the imperviousness prediction - Data Type of DEM composed of 1 band and a Continuous Variable Type. Data Type of Slope composed of 1 band and a Continuous Variable Type. Data Type of Aspect composed of 1 band of Categorical Variable Type. Data type of Position Index composed of 1 band of Continuous Variable Type. Ancillary data used for urban area masking include: 1. NOAA Defense Meteorological Satellite Program 1 km city light data (1 band) 2. MRLC 1992 classification (1 band) 3. TIGER 2000 roads (1 band) Background / No Data was set to pixel value 127 for the February 2, 2015 release of this dataset.
      Source_Used_Citation_Abbreviation: Landsat ETM, DEM
      Process_Date: Unknown
      Source_Produced_Citation_Abbreviation: USGS NLCD
      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: USGS EROS
            Address: 47914 252nd Street
            City: Sioux Falls
            State_or_Province: SD
            Postal_Code: 57198-0001
            Country: USA
          Contact_Voice_Telephone: 605/594-6151
          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 USGS point of contact is for questions relating to the data display and download from this web site. Questions about the NLCD mapping zone ak08 can be directed to the NLCD 2001 land cover mapping team at USGS EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.

Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Raster
  Raster_Object_Information:
    Raster_Object_Type: Pixel
    Row_Count: 13476
    Column_Count: 7093
    Vertical_Count: 1

Spatial_Reference_Information:
  Horizontal_Coordinate_System_Definition:
    Planar:
      Map_Projection:
        Map_Projection_Name: Albers Conical Equal Area
        Albers_Conical_Equal_Area:
          Standard_Parallel: 55.000000
          Standard_Parallel: 65.000000
          Longitude_of_Central_Meridian: -154.000000
          Latitude_of_Projection_Origin: 50.000000
          False_Easting: 0.000000
          False_Northing: 0.000000
      Planar_Coordinate_Information:
        Planar_Coordinate_Encoding_Method: row and column
        Coordinate_Representation:
          Abscissa_Resolution: 30.000000
          Ordinate_Resolution: 30.000000
        Planar_Distance_Units: meters
    Geodetic_Model:
      Horizontal_Datum_Name: World Geodetic System 1984
      Ellipsoid_Name: World Geodetic System 1984
      Semi-major_Axis: 6378137.0
      Denominator_of_Flattening_Ratio: 298.2572235

Entity_and_Attribute_Information:
  Detailed_Description:
    Entity_Type:
      Entity_Type_Label: Layer_1
      Entity_Type_Definition: NLDC Imperviousness Layer
      Entity_Type_Definition_Source: National Land Cover Database 2001
    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_Definition: Percent Imperviousness
      Attribute_Definition_Source: NLCD 2001
      Attribute_Domain_Values:
        Range_Domain:
          Range_Domain_Minimum: 0
          Range_Domain_Maximum: 100
          Attribute_Units_of_Measure: percentage
          Attribute_Measurement_Resolution: 0.1
      Attribute_Domain_Values:
        Enumerated_Domain:
          Enumerated_Domain_Value: 127
          Enumerated_Domain_Value_Definition: Background / No Data
          Enumerated_Domain_Value_Definition_Source: NLCD land cover class descriptions
    Attribute:
      Attribute_Label: Count
      Attribute_Definition:
        A nominal integer value that designates the number of pixels that have each value in the file; histogram column in ERDAS Imagine raster attributes table
      Attribute_Definition_Source: NLCD 2001
      Attribute_Domain_Values:
        Unrepresentable_Domain: Integer
    Attribute:
      Attribute_Label: Red
      Attribute_Definition:
        Red color code for RGB slice by value for imperviousness image display purposes. The value is arbitrarily assigned by the display software package, unless defined by user. Standard user defined ramp for NLCD project is start color light gray, end color red.
      Attribute_Definition_Source: NLCD 2001
      Attribute_Domain_Values:
        Range_Domain:
          Range_Domain_Minimum: 0
          Range_Domain_Maximum: 100
          Attribute_Units_of_Measure: CSS Color Value Percentage
          Attribute_Measurement_Resolution: 0.1
    Attribute:
      Attribute_Label: Green
      Attribute_Definition:
        Green color code for RGB slice by value for imperviousness image display purposes. The value is arbitrarily assigned by the display software package, unless defined by user. Standard user defined ramp for NLCD project is start color light gray, end color red.
      Attribute_Definition_Source: NLCD 2001
      Attribute_Domain_Values:
        Range_Domain:
          Range_Domain_Minimum: 0
          Range_Domain_Maximum: 100
          Attribute_Units_of_Measure: CSS Color Value Percentage
          Attribute_Measurement_Resolution: 0.1
    Attribute:
      Attribute_Label: Blue
      Attribute_Definition:
        Blue color code for RGB slice by value for imperviousness image display purposes. The value is arbitrarily assigned by the display software package, unless defined by user. Standard user defined ramp for NLCD project is start color light gray, end color red.
      Attribute_Definition_Source: NLCD 2001
      Attribute_Domain_Values:
        Range_Domain:
          Range_Domain_Minimum: 0
          Range_Domain_Maximum: 100
          Attribute_Units_of_Measure: CSS Color Value Percentage
          Attribute_Measurement_Resolution: 0.1
    Attribute:
      Attribute_Label: Opacity
      Attribute_Definition:
        A measure of how opaque, or solid, a color is displayed in a layer.
      Attribute_Definition_Source: NLCD 2001
      Attribute_Domain_Values:
        Range_Domain:
          Range_Domain_Minimum: 0
          Range_Domain_Maximum: 100
          Attribute_Units_of_Measure: Percentage
          Attribute_Measurement_Resolution: 0.1
  Overview_Description:
    Entity_and_Attribute_Overview: Attributes defined by USGS and ESRI.
    Entity_and_Attribute_Detail_Citation:
      Attribute accuracy is described, where present, with each attribute defined in the Entity and Attribute Section. Note: To ensure all areas of mapping zone ak08 are completely covered, a 3,000 meter (100 Landsat pixels) buffer was added to the boundary of mapping zone ak08.

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: USGS National Geospatial Program Office
        Address: 12201 Sunrise Valley Drive
        City: Reston
        State_or_Province: VA
        Postal_Code: 20192
        Country: USA
      Contact_Voice_Telephone: 1-888-ASK-USGS (1-888-275-8747)
      Contact_Electronic_Mail_Address: tnm_help@usgs.gov
      Hours_of_Service: Monday through Friday 8:00 AM to 4:00 PM Eastern Time Zone USA
      Contact_Instructions: Please visit <http://www.usgs.gov/ask/> to contact us.
  Resource_Description: Downloadable Data
  Distribution_Liability:
    Although these data have been processed successfully on a computer system at the USGS, no warranty expressed or implied is made by the USGS regarding the use of the data on any other system, nor does the act of distribution constitute any such warranty. Data may have been compiled from various outside sources. Spatial information may not meet National Map Accuracy Standards. This information may be updated without notification. The USGS shall not be liable for any activity involving these data, installation, fitness of the data for a particular purpose, its use, or analyses results.
  Standard_Order_Process:
    Digital_Form:
      Digital_Transfer_Information:
        Format_Name: TIFF
        Transfer_Size: 3.083232
      Digital_Transfer_Option:
        Online_Option:
          Computer_Contact_Information:
            Network_Address:
              Network_Resource_Name:
                <http://gisdata.usgs.gov/tdds/downloadfile.php?TYPE=nlcd2001_imp_state&ORIG=META&FNAME=NLCD2001_IMP_Alaska.zip>
          Access_Instructions:
            The URL <http://nationalmap.gov/viewer.html> provides a map interface that allows for viewing and data downloads within a customer defined area of interest. Zoom tools are available that can be used to investigate areas of interest on the map interface. The download tool allows the customer to capture layers from the map, utilizing The National Map process for downloading. The file can be unzipped and imported into various user software applications.
          Online_Computer_and_Operating_System: Not available for dissemination
    Fees: None
    Ordering_Instructions: Contact Customer Service
    Turnaround: Variable
  Custom_Order_Process: Contact Customer Service Representative
  Technical_Prerequisites:
    ESRI ArcGIS Suite and/or Arc/Info or other compatible software, and supporting operating systems.
  Available_Time_Period:
    Time_Period_Information:
      Range_of_Dates/Times:
        Beginning_Date: 2015
        Ending_Date: Unknown

Metadata_Reference_Information:
  Metadata_Date: 20150115
  Metadata_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: USGS EROS
        Address: 47914 252nd Street
        City: Sioux Falls
        State_or_Province: SD
        Postal_Code: 57198-0001
        Country: USA
      Contact_Voice_Telephone: 605/594-6151
      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)
  Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
  Metadata_Standard_Version: FGDC-STD-001-1998
  Metadata_Time_Convention: local time
  Metadata_Access_Constraints: None
  Metadata_Use_Constraints: None

Generated by `mp` version 2.9.8 on Fri Mar 27 11:32:44 2015