The MISR team has developed new methods for retrieving information
about clouds, airborne particles, and surface properties that
capitalize on the instrument's unique, multi-angle imaging approach.
This illustration, based upon results contained in sample products that
have just been publicly released at the Atmospheric Sciences Data
Center (ASDC), highlights some of these new capabilities. The ASDC,
located at NASA's Langley Research Center, is the primary processing
and archive center for MISR data (http://eosweb.larc.nasa.gov/).
On August 21, 2000, during Terra orbit 3600, MISR imaged Hurricane Debby
in the Atlantic Ocean. The first panel on the left is the MISR downward-
looking (nadir) view of the storm's eastern edge. The next two panels
show the results of a new approach that uses MISR's stereoscopic
observations to retrieve cloud heights and winds. In the middle panel
of this set, gradations from low to high cloud are depicted in shades
ranging from blue to red. Since it takes seven minutes for all nine
MISR cameras to view any location on Earth, and the clouds moved during
this time, the data also contain information about wind speed and
direction. Derived wind vectors, shown in the third panel, reveal
Hurricane Debby's cyclonic motion. The highest wind speed measured is
nearly 100 kilometers/hour. MISR obtains this type of information on a
global basis, which will help scientists study the relationship between
climate change and the three-dimensional characteristics of clouds.
MISR imaged the eastern United States on March 6, 2000, during Terra
orbit 1155. The first panel in the righthand set is the downward-
looking (nadir) view, covering the region from Lake Ontario to northern
Georgia, and spanning the Appalachian Mountains. The middle panel is
the image taken by the forward-viewing 70.5-degree camera. At this
increased slant angle, the line-of-sight through the atmosphere is
three times longer,and a thin haze over the Appalachians is
significantly more apparent. MISR uses this enhanced sensitivity along
with the variation of brightness with angle to monitor particulate
pollution and to measure haze properties. The third panel shows the
airborne particle (aerosol) amount, derived using new methods that take
advantage of MISR's moderately high spatial resolution at very oblique
angles. The aerosol results are obtained at coarser resolution than
the underlying images; gradations from blue to red indicate increasing
aerosol abundance. These data indicate how airborne particles are
interacting with sunlight, a measure of their impact on Earth's climate.
Image Credit: NASA/GSFC/JPL, MISR Team
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