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NASA/JPL/NIMA.
"AmericaSRTM-NorthPortland-picasa.jpg"
Online Image. Shuttle Radar Topography Mission. 20 Jan. 2006 119kb. 944x353px.
<http://photojournal.jpl.nasa.gov/catalog/PIA04966>
Portland, Oregon - Mt. Hood
This image shows a perspective view created by draping a Landsat image over the elevation framework
from an SRTM data set for Mt. Hood and the city of Portland.
It was created from an original map produced from data obtained by NASA's
Shuttle Radar Topography Mission (SRTM). Using Google's free Picasa2 program, the
color, contrast, and lighting were enhanced. It was then sharpened to obtain the image above. The
original image can be viewed at the NASA link above.
Portland, the largest city in Oregon, is located on the Columbia River at the northern end of the
Willamette Valley. On clear days, Mount Hood highlights the Cascade Mountains backdrop to the east.
The Columbia is the largest river in the American Northwest and is navigable up to and well beyond
Portland. It is also the only river to fully cross the Cascade Range, and has carved the Columbia
River Gorge, which is seen in the left-central part of this view. A series of dams along the river,
at topographically favorable sites, provide substantial hydroelectric power to the region. This
perspective view was generated using topographic data from the Shuttle Radar Topography Mission
(SRTM), a Landsat satellite image, and a false sky. Topographic expression is vertically exaggerated
two times. Landsat has been providing visible and infrared views of the Earth since 1972.
SRTM elevation data substantially help in analyzing Landsat images by revealing the third dimension
of Earth's surface, topographic height. The Landsat archive is managed by the U.S. Geological Survey's
Eros Data Center (USGS EDC).
Size: View width 88 kilometers (49 miles), View distance 106 kilometers (66 miles)
Location:
45.5 degrees North latitude, 122.5 degrees West longitude
Orientation: View East-Southeast,
10 degrees below horizontal, 2 times vertical exaggeration
Image Data: Landsat Bands 3, 2, 1
as red, green, blue, respectively
Date Acquired: February 2000 (SRTM), August 10, 1992 (Landsat)
NASA/JPL/NIMA.
Shuttle Radar Topography Mission. 20 Jan. 2006
<http://photojournal.jpl.nasa.gov/catalog/PIA04966>
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