Remote Sensing: Pivotal Technologies for Environmental Sciences

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Remote SensingPivotal Technologies for
Environmental Sciences
CSTARS employs emergent imaging technologies for
a wide range of applications including
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Introduction
What is remote sensing? Remote sensing is the
acquisition of information about the environment
from a distance.
Our laboratory employs a wide array of sensors on
many different platforms
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Image Acquisition
How are remote images acquired? Spectrometers
record reflected sunlight at specific
wavelengths. Detection is limited by the
instrument's spatial resolution (the smallest
distinguishable object) and its spectral
resolution (how many spectral bands and at what
wavelengths).
Animation courtesy of NASA
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Data Processing
How is the data processed? After acquisition, the
image is georeferenced so the location of all
pixels is known. Images are calibrated to account
for atmospheric conditions and instrument
characteristics. The data can be compared to
images from other locations, dates, or sensors.
After georeferencing, we see the image is now
recognizable and usable by researchers.
Aerial platforms are inherently unstable, so
images acquired are often heavily distorted.
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Image Analysis
How are images interpreted? Researchers combine
earth science, mathematics, and image processing
to interpret the image. In this example, remote
images
maps showing seasonal change in a biological
preserve.
field based data, and
topography are used to create
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Precision AgricultureCotton
Remote sensing can give farmers precise
information about crop conditions. Water
scheduling is a key farm management decision.
Remote sensing can help farmers avoid
unnecessary irrigation.
True color image of cotton fields
Water stress levels (red and yellow are stressed
regions).
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Environmental ManagementForestry
Remote sensing is used to monitor the health of
ecosystems.
Extensive logging in the Gifford Pinchot National
Forest in southwest Washington has changed the
structure and functioning of the forest
ecosystem. Note the patchwork of forested and
disturbed areas in this flyover.
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Environmental ManagementHydrology
Efficient water monitoring protects resources and
provides early warning of threats to water
quality. Topographic depth profiles such as this
image of Lake Tahoe are used to improve image
interpretation.
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Natural HazardsFire Monitoring
and in the shortwave infrared, the fire itself
is now visible.
In the visible region of the spectrum, smoke
obscures the ground
while in the near infrared, the ground can now
be seen
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Atmospheric Science
Cloud top temperatures are used to estimate
rainfall. These images from the GOES weather
satellite show the location of the storm core as
a dark spot.
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Global Change
The size and dynamics of the current ozone hole
over Antarctica, the largest ever recorded, are
only known through satellite images.
Image courtesy of NASA
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Future Directions
CSTARS is at the forefront in developing advanced
imaging tools in collaboration with industry and
NASA JPL. Current projects include imagers on