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Microwave Image | Visible Light Image |
Infrared, microwave, and visible/near-infrared images of Hurricane Hector
in the eastern Pacific were created with data from the Atmospheric
Infrared Sounder (AIRS) on NASA's Aqua satellite on August 17, 2006.
The infrared AIRS image shows the temperature of the cloud tops or the
surface of the Earth in cloud-free regions. The lowest temperatures (in
purple) are associated with high, cold cloud tops that make up the top of
the hurricane. The infrared signal does not penetrate through clouds.
Where there are no clouds the AIRS instrument reads the infrared signal
from the surface of the Earth, revealing warmer temperatures (red). At the
time the data were taken from which these images were made, Hector is a
well organized storm, with the strongest convection in the SE quadrant.
The increasing vertical wind shear in the NW quadrant is appearing to have
an effect. Maximum sustained winds are at 85 kt, gusts to 105 kt.
Estimated minimum central pressure is 975 mbar.
The microwave image is created from microwave radiation emitted by Earth's
atmosphere and received by the instrument. It shows where the heaviest
rainfall is taking place (in blue) in the storm. Blue areas outside of the
storm where there are either some clouds or no clouds, indicate where the
sea surface shines through.
The "visible" image is created from data acquired by the visible
light/near-infrared sensor on the AIRS instrument.
The Atmospheric Infrared Sounder Experiment, with its visible, infrared,
and microwave detectors, provides a three-dimensional look at Earth's
weather. Working in tandem, the three instruments can make simultaneous
observations all the way down to the Earth's surface, even in the presence
of heavy clouds. With more than 2,000 channels sensing different regions
of the atmosphere, the system creates a global, 3-D map of atmospheric
temperature and humidity and provides information on clouds, greenhouse
gases, and many other atmospheric phenomena. The AIRS Infrared Sounder
Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's
Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL
is a division of the California Institute of Technology in Pasadena.