The extent, height, and amount of smoke originating from the B&B Complex
Fires in central Oregon are captured in these September 4, 2003 views from
the Multi-angle Imaging SpectroRadiometer (MISR). When the data were
acquired, the Booth and Bear Butte Fires had been underway for 16 days and
had consumed about 70,000 acres near Sisters, Oregon. Although a distinct
plume rises from the location of the Bear Butte Fire (just northwest of
the larger Booth Fire), the fire-lines had merged together by this time
and became known as the B&B Complex. Centered in the Deschutes and
Willamette National Forests, the blazes in these mixed-conifer old-growth
forests were aided by earlier dry conditions and fed by heavy fuel loads,
regeneration timbers, and large tracts of beetle-killed dead woods.
The left and center-left panels are natural-color images from MISR's
vertical-viewing (nadir) and most obliquely forward-viewing (70-degree)
cameras, respectively. The appearance of smoke and haze is enhanced at the
more oblique view. The center-right panel is a height field for features
exhibiting sufficient spatial contrast for their elevations to be
retrieved by MISR's automated stereo algorithm. The results indicate that
the tops of the two main plumes originating from the B&B complex differ in
altitude by about 1-2 kilometers. At right is a map of aerosol optical
depth, a measure of the amount of aerosol particles present within the
atmospheric column. In the central portion of the plume, the smoke was too
thick for MISR's automated optical depth retrieval algorithm to work, and
over these areas or locations where clouds or other factors precluded a
retrieval the map is colored black.
The animation depicts a "multi-angle fly-over" of the plumes, and was
generated using red-band data from MISR's vertical and backward-viewing
cameras. The imagery at each angle was processed to give an approximate
perspective view. The final frame of the animation is at the 70-backward
viewing angle, and makes visible the relative heights of several plumes
and nearby clouds. The dashed line across this image is a data dropout.
The Multi-angle Imaging SpectroRadiometer observes the daylit Earth
continuously from pole to pole, and every 9 days views the entire globe
between 82 degrees north and 82 degrees south latitude. These data
products were generated from a portion of the imagery acquired during
Terra orbit 19753. The panels cover an area of approximately 400
kilometers x 986 kilometers and extend from northern California to central
Washington. They utilize data from blocks 52 to 58 within World Reference
System-2 path 44.
MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.
Image credit: NASA/GSFC/LaRC/JPL, MISR Team.
Text acknowledgment: Clare Averill (Raytheon/Jet Propulsion Laboratory).
Animation acknowledgment: Michael Garay (UCLA/Jet Propulsion Laboratory).
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