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NASA Rainforest Deforestation
Images
These
images shows fires and smoke plumes near the Xingu River in the Brazilian
Amazon. Fire locations are superimposed in red on the true-color image, taken by
the Moderate-resolution
Imaging Spectroradiometer (MODIS) aboard NASA's Terra
satellite on May 2, 2001. Fire locations are superimposed in red on the
true-color image. Virgin forest is dark green, while land cleared for
agriculture is lighter green or brown. Fire is the principle method used to
clear new land. Although peak burning season is July through September, there
are already 20 or more fires that can be seen burning in this image. The
deforestation of the Amazon River Basin is one of the world's best-known
environmental problems. MODIS will help scientists study the region in several
ways. MODIS' thermal detectors can directly detect fires, as shown above. Specifically, the instrument can measure the intensities of
fires, thus enabling scientists to more accurately estimate their rates of
combustion and the amounts of emission products--such as smoke, greenhouse
gases, and aerosol particles--they release into the atmosphere.
NASA's
MODIS Terra Image
Rondonia,
Brazil
This image shows the extent of
deforestation in the state of Rondonia, Brazil. Acquired by the Advance
Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on August 24,
2000, the false-color image combines near-infrared, red, and green light.
Tropical rainforest appears bright red, while pale red and brown areas represent
cleared land. Black and gray areas have probably been recently burned. The
Jiparaná River appears blue.
This
high-resolution image of Amazonia shows farms cleared from the jungle spreading
out on either side of a narrow dirt road. Above and to the right of the river
that bisects the image is almost unbroken forest. The river, a tributary of the
Amazon, is colored brown by the large amount of sediment it carries, possibly
the result of deforestation upstream.-NASA GFSC
With a maximum spatial resolution
of 15 meters, ASTER does not produce imagery as detailed as the IKONOS
satellite, which has a maximum resolution of one meter. Compare the above image
with IKONOS data from the same area. The somewhat lower resolution ASTER data is
not as detailed, but provides a better overview, and ASTER can acquire data over
a particular region more often than IKONOS. Other satellite instruments, such as
the Sea-viewing Wide Field-of-View Sensor (SeaWiFS), give even broader and more
frequent coverage, as shown by this true-color image of Rondonia.
Some areas of Rondonia,
Brazil, have been almost completely deforested in just 6 years. This pair of
images uses a scale, or index, of vegetation to compare forest area in 2000 to
2006 at the full resolution (15 meters per pixel) of the Advanced Spaceborne
Thermal Emission and Reflection Radiometer (ASTER) instrument. Cleared areas
(tan) spread from roads cut through the forest (green), a pattern of
deforestation typical in Rondonia. (Maps by Robert Simmon, based on ASTER
data.)
To learn more about
Rainforests visit the following
organizations
Credit: NASA, USGS, Woods Hole
Research Center, Wikipedia, San Diego Zoo
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