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Canopy Coverage Portland Metro, Oregon 1998

Identification Information

Citation
Title
Canopy Coverage Portland Metro, Oregon 1998
Originator
Metro Data Resource Center
Publication Date
2001-02-01
Identifier
https://geodiscovery.uwm.edu/catalog/ark:-77981-gmgsrr1pm32
Geospatial Data Presentation Form
mapDigital
Abstract
This TIF data layer represents canopy coverage for Portland Metro, Oregon in 1998. The spatial resolution of the dataset is 25 meters. The dataset was originally published by the Metro Data Resource Center in February 2001.[The classification and mapping of urban forest canopy cover was accomplished using Landsat TM digital satellite imagery. Landsat TM data includes spectral reflectance information from the visible, near-infrared, and middle-infrared portions of the spectrum and has a resampled spatial resolution of 25-meters. Tthe wide range spectral information contained in Landsat TM data makes it ideal for classifying vegetation such as forest canopy cover. Moreover, Landsat TM data was used to produce the original 1991-based land cover map for the Portland area. As described in the following section, the 1998 Landsat TM scene was also utilized in the development of the 1998-revised land cover map. These forest canopy cover classes were selected due to the proven ability of Landsat TM imagery to effectively discriminate this level of forest cover detail. In addition, other vegetation cover mapping projects in and surrounding the Willamette Valley have used these same or similar cover class discriminations. Unsupervised classification techniques were used to discriminate and map forest canopy cover. The goal in any image classification project is to determine when the image is a good predictor of the vegetative characteristic of interest, such as forest canopy cover. ERDAS Imagine digital image processing software was utilized to stratify the Landsat TM imagery into approximately 150 spectral classes based solely on the spectral information in the image data set. Spectral responses in the imagery, aerial photo and digital orthophotography interpretation, and ancillary GIS data were utilized to determine which spectral classes represent forested areas and subsequently to categorize each forested spectral class into the appropriate canopy cover class. For instance, 51 to 75% tree canopy cover in a residential area is categorized into the same class as an area of 51 to 75% forest canopy cover in a natural area.]
Purpose
This layer is intended for reference and mapping purposes and may be used for basic applications such as viewing, querying, and map output production or to provide a basemap to support graphical overlays and analysis with other spatial data.
Supplemental Information
Augmented original metadata with AGSL specific elements. For official metadata contact the resource Point of Contact. Also see CANOPY98.HTM.
Temporal Extent
Bounding Box
West
-123.422522
East
-121.971674
North
45.808199
South
45.069469
ISO Topic Category
environment
Place Keyword
Portland Metro
Oregon
Place Keyword Thesaurus
GeoNames
Theme Keyword
Raster
Theme Keyword Thesaurus
FGDC
Theme Keyword
Forest canopies
Urban forestry
Theme Keyword Thesaurus
LCSH
Resource Constraints
Use Limitation
Please see the UWM Libraries statement on Copyright and Digital Collections.
Legal Constraints
Use Limitation
Although this data is being distributed by the American Geographical Society Library at the University of Wisconsin-Milwaukee Libraries, no warranty expressed or implied is made by the University as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the University in the use of this data, or related materials.
Other Restrictions
None
Status
completed
Maintenance and Update Frequency
notPlanned
Language
eng
Credit
Metro Data Resource Center
Point of Contact
Contact
Metro Data Resource Center
Email
DRC@oregonmetro.gov
Phone
503-797-1742

Spatial Reference Information

Reference System Identifier
Code
2913
Code Space
EPSG
Version
6.13(9.0.0)

Data Quality Information

Quantitative Attribute Accuracy Report
Result
Lineage
Process Step
Description
Projected data and changed name of file from CANOPY98.TIF to PortlandMetro_CanopyCoverage_1998.TIF.

Distribution Information

Format Name
Raster Dataset
Format Version
Distributor
University of Wisconsin-Milwaukee
Distributor
Metro Data Resource Center

Content Information

Content Type
thematicClassification

Spatial Representation Information

Raster
Number of Dimensions
2
Column Count
4457
Row Count
3165
Cell Geometry Type
area
Corner Points

Metadata Reference Information

Hierarchy Level
dataset
Metadata File Identifier
ark:/77981/gmgsrr1pm32
Dataset URI
https://geodata.uwm.edu/public/gmgsrr1pm32/PortlandMetro_CanopyCoverage_1998.zip
Metadata Point of Contact
Name
American Geographical Society Library – UWM Libraries
Position Name
GIS Staff
Delivery Point
2311 E Hartord Ave
City
Milwaukee
Administrative Area
WI
Postal Code
53211
Country
US
Email
gisdata@uwm.edu
Phone
(414)-229-6282
Metadata Date Stamp
2023-10-23
Metadata Standard Name
ISO 19139 Geographic Information - Metadata - Implementation Specification
Metadata Standard Version
2007
Character Set
utf8
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