Frances, Ivan Contribute to Hurricane Studies
Seen through the eyes of the Multi-angle Imaging
SpectroRadiometer aboard NASA's Terra satellite, the menacing
clouds of Hurricanes Frances and Ivan provide a wealth of
information that can help improve hurricane forecasts.
Seen through the eyes of the Multi-angle Imaging
SpectroRadiometer aboard NASA's Terra satellite, the menacing
clouds of Hurricanes Frances and Ivan provide a wealth of
information that can help improve hurricane forecasts.The ability of forecasters to predict the intensity and amount of
rainfall associated with hurricanes still requires improvement,
particularly on the 24- to 48-hour timescales vital for disaster
planning.  Scientists need to better understand the complex
interactions that lead to hurricane intensification and
dissipation, and the various physical processes that affect
hurricane intensity and rainfall distributions.  Because
uncertainties in representing hurricane cloud processes still
exist, it is vital that model findings be evaluated against
actual hurricane observations whenever possible.  Two-dimensional
maps of cloud heights such as those provided by the Multi-angle
Imaging SpectroRadiometer offer an unprecedented opportunity for
comparing simulated cloud fields against actual hurricane
observations.The newly released images of Hurricanes Frances and Ivan were
acquired Sept. 4 and Sept. 5, 2004, respectively, when Frances'
eye sat just off the coast of eastern Florida and Ivan was
heading toward the central and western Caribbean.  They are
available at:http://photojournal.jpl.nasa.gov/catalog/PIA04367.The left-hand panel in each image pair is a natural-color view
from the instrument's nadir camera.  The right-hand panels are
computer-generated cloud-top height retrievals produced by
comparing the features of images acquired at different view
angles.  When these images were acquired, clouds within Frances
and Ivan had attained altitudes of 15 and 16 kilometers (9.3 and
9.9 miles) above sea level, respectively.The instrument is one of several Earth-observing experiments
aboard Terra, launched in December 1999.  The instrument acquires
images of Earth at nine angles simultaneously, using nine
separate cameras pointed forward, downward and backward along its
flight path.  It observes the daylit Earth continuously and every
9 days views the entire globe between 82 degrees north and 82
degrees south latitude.  It was built and is managed by NASA's
Jet Propulsion Laboratory, Pasadena, Calif.  JPL is a division of
the California Institute of Technology in Pasadena.More information about the Multi-angle Imaging SpectroRadiometer
is available at:http://www-misr.jpl.nasa.gov/.Alan Buis (818) 354-0474JPL2004-229