King County 2001 Landsat TM Change Detection: lcchg_imp and lcchg_for

Metadata also available as - [Outline] - [Parseable text] - [SGML] - [XML] - [DIF]

Frequently-anticipated questions:

What does this data set describe?

    King County 2001 Landsat TM Change Detection: lcchg_imp and lcchg_for

    Data set is a 1994 to 2001 landcover change interpretation derived from Landsat TM scenes. The source scene row/path was Path 46, Row 27. The scenes were clipped to a bounding box that encompassed the extent of King County and Southwestern Snohomish County. Two separate grids were produced, one grid depicting all grid cells changed from any landcover class (except impervious) to Urban/Impervious surface, i.e. this product shows growth of impervious surfaces (lcchg_imp) and one depicting all grid cells changed from forest canopy classes to other classes, i.e. this product will show loss of forest canopy (lcchg_for). The processing method used a Hybrid Change Detection, which combines radiometric change and categorical difference.
    This landcover change detection was created by Marshall and Associates, Inc. as part of a multiple part effort to interpret impervious surface categories from high-resolution multispectral imagery.

  1. How should this data set be cited?

    County, King, 20020621, King County 2001 Landsat TM Change Detection: lcchg_imp and lcchg_for : King County, King County, WA.

    Online Links:

    • None

    This digital data was created by Marshall and Associates, Inc,under contract to King County, contract number: T01393.

    Marshall and Associates 1603 Cooper Point Rd NW Olympia, WA 98502-8325

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -122.56
    East_Bounding_Coordinate: -121.04
    North_Bounding_Coordinate: +47.97
    South_Bounding_Coordinate: +47.06

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Beginning_Date: 1994
    Ending_Date: 11-Aug-2001
    Currentness_Reference: TM Scene date, 20010811

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: Raster digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      King County and Southwestern Snohomish County, WA with a minimum of a 12 km buffer from the project boundary.
      This is a Raster data set.

    2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: State Plane
      SPCS_Zone_Identifier: 4601 (FIPS)
      Standard_Parallel: 47.5
      Standard_Parallel: 48.7333
      Longitude_of_Central_Meridian: -120.8333
      Latitude_of_Projection_Origin: 47.0
      False_Easting: 500,000 M
      False_Northing: 0

      Planar coordinates are encoded using Coordinate Pair
      Abscissae (x-coordinates) are specified to the nearest Not Determined
      Ordinates (y-coordinates) are specified to the nearest Not Determined
      Planar coordinates are specified in U.S. Survey Feet


  7. How does the data set describe geographic features?

    lcchg_imp.vat and lcchg_for.vat
    Feature attribute table for each respective grid. (Source: King County internal coding. Classification schema and definitions were determined through consensus of a working group comprised of representatives from multiple county departments.)

    Default ArcInfo grid cell value (Source: Assignment through processing steps)

    Range of values

    Cell count in grid (Source: Software-generated)

    Integer value

    Landuse/Landcover Identifier (Source: King County Internal classification identifier)

    0Not change
    1Change (loss of forest/increase in impervious)

    Each landcover grid contains a single feature attribute table, 'grid- name'.vat containing 2 items shown below in the entity detail. For most users only value columns are significant. Explanation of the class descriptions can be found in

    Entity_and_Attribute_Detail_Citation: None

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    Mike Leathers
    King County Dept. of Transportation/ Road Services
    Project Manager
    155 Monroe Ave NE
    Renton, WA 98056

    206-296-8073 (voice)

Why was the data set created?

The landcover interpretation was created to provide an up-to-date landcover interpretation for the project area. The classification scheme was devised considering various county-wide mandates affecting multiple departments.

Primary drivers for the classification schema and effort are implementation of Endangered Species Act mandates, buildable lands definition and sensitive areas mitigation.

How was the data set created?

  1. From what previous works were the data drawn?

    ETM+,TM (source 1 of 1)
    U.S. Geological Survey, Eros Data Center, 20020107, Landsat Enhanced Thematic Mapper Plus: USGS, EROS Data Center.

    System processing, orthorectification by Marshall and Associates, Inc
    Type_of_Source_Media: Raster digital data
    Source_Contribution: These TM scenes provided the basis for land change detection.

  2. How were the data generated, processed, and modified?

    Date: Jun-2002 (process 1 of 1)
    See Process Document

    Data sources used in this process:

    • ETM+,TM

  3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?


  2. How accurate are the geographic locations?

    The 2001 image was acquired from the Snohomish County Public Works Department. It is an NALP product of a LANDSAT 7 ETM+ image with a systematic level processing (meaning satellite ephemeris information was the source of georectification). This was found to be a geoprecision level of approximately 3 pixels alignment to the 7 July 2000 orthorectified image purchased for this project. The 1994 image is a Map-oriented processing level Landsat 5 Thematic Mapper Image at 25 meter resolution (five pixels for 1994). Appropriate Process steps to orthorectify the 1994 and 2001 were done by Marshall and Associates, Inc. Center to center pixel spacing is 25 meters with an average horizontal accuracy of 22.8 meters.

  3. How accurate are the heights or depths?


  4. Where are the gaps in the data? What is missing?

    There are no gaps in the data. All cells were classified as one of the values found in the entity section.

  5. How consistent are the relationships among the observations, including topology?

    all cell values in the range of 0-1. A 0 value represents no change and a 1 value represents change from 1994-2001

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Online access is restricted to authenticated King County users Others may access the data through KC GIS Center Client Services.

King County data are made available with the understanding that they shall be used exclusively by the obtainer or his/her authorized agents. Digital produce may not be reproduced or redistributed in any form or by any means without the express written authorization of King Co. GIS Center. This dataset is not accurate enough to support parcel level analyses and mapping. It is suitable for watershed level uses only.

No Representations Marshall and Associates, Inc. (hereinafter MARSHALL) and its supplier make no representations or warranties with respect to any imagery or products derived from imagery supplied to a Client with the exception of those specified in a legal contract agreed upon both by MARSHALL and the Client.

Limited Warranty The Client shall indemnify and hold harmless MARSHALL and its supplier from any circumstances that arise from the use of imagery or information supplied by MARSHALL for any other purpose or use besides that expressly outlined in the MARSHALL /Client contract

Limitation of Liability Neither MARSHALL nor its supplier, their affiliates, officers, directors, shareholders, agents, and employees shall be liable for any loss or damage suffered by the Client, or any party claiming through the Client, as a result of or related to the provision by MARSHALL of any data, information, or images.

Reselling and Distributing Data The Client shall not resell to any third party any data, information, or images provided by MARSHALL unless the Client obtains from such third party a disclaimer of representations and a confirmation of limitations of liability and the Client shall ensure that MARSHALL and its supplier is a beneficiary of such disclaimers and limitations (even if only indirectly named as a supplier of the data, information, or images). The Client shall indemnify and hold harmless MARSHALL and its supplier from and against any claims made by third parties to whom the Client resells the data, information, or images supplied by MARSHALL.

  1. Who distributes the data set? (Distributor 1 of 1)

    Cheryl Wilder
    King County GIS Center
    Training Coordinator
    201 S. Jackson St, Room 706
    Seattle, WA 98104

    206-263-5220 (voice)

  2. What's the catalog number I need to order this data set?

    lcchg_imp, lcchg_for, lcchg_wet

  3. What legal disclaimers am I supposed to read?

    King County disclaims any warranty of use of any digital product or data beyond that for which it was designed.

  4. How can I download or order the data?

Who wrote the metadata?

Last modified: 10-Jun-2002

Metadata author:
Naomi Marshall
Marshall and Associates, Inc
Technical Writer
1603 Cooper Point Road NW
Olympia, WA 98502-8325

360-352-1279 (voice)

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)

Generated by mp version 2.7.17 on Tue Oct 15 14:24:13 2002