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Three federal agencies and the British Antarctic Survey
(BAS) today unveiled a uniquely detailed and scientifically
accurate satellite mosaic map of Antarctica that is expected
to become a standard geographic reference and will give
both scientists and the general public an unmatched tool
for studying the southernmost continent.
Representatives of the National Science Foundation (NSF),
the U. S. Geological Survey (USGS), the National Aeronautics
and Space Administration (NASA) and BAS worked cooperatively
to produce the Landsat Image Mosaic of Antarctica (LIMA),
a map that combines more than 1,100 hand-selected Landsat
satellite scenes digitally compiled to create a single,
seamless, cloud-free image.
The new map was introduced to the media and public during
an event at NASA's Goddard Space Flight Center in Greenbelt,
Md.
At a moment in history when there is unprecedented concern
about the state of the polar ice caps in the face of documented
regional Arctic and Antarctic warming trends, the LIMA
mosaic provides a critical "snapshot in time"
of of Antarctica's ice sheets, which contain over 60 percent
the world's fresh water, noted Scott Borg, director of
NSF's division of Antarctic sciences.
"But LIMA is also a fundamental tool for scientists.
It will be used in every discipline from biology to geology
to glaciology, both to answer scientific questions and
plan fieldwork in the vast unexplored tracts of Antarctica.
For educators, students, and the general public, LIMA
will bring to life the Antarctic continent like nothing
before it," Borg said. "Imagine a middle-school
Earth-science student comparing landforms in the glaciated
valleys of Antarctic to similar features in the Rocky
Mountains or even comparing a rock glacier in Antarctica
with some of the features scientists are studying in images
from Mars."
"This mosaic draws on 35 years of experience by
the USGS's Earth Resources Observation and Science (EROS)
center, whose goals include the preservation of and access
to the Nation's remotely sensed land data assets through
the National Satellite Land Remote Sensing Data Archive,"
said Barbara Ryan, USGS associate director for geography.
LIMA was produced using EROS images from the Landsat 7
satellite launched in 1999.
The Landsat Program began in 1972, with the launch of
the first Landsat satellite. "Sensors aboard Landsat
satellites have captured millions of digital images of
the Earth's land masses and coastal regions used by researchers
worldwide to study global change, natural disasters, and
other aspects of the Earth's terrestrial environment,"
Ryan said.
Robert Bindschadler, chief scientist of the Hydrospheric
and Biospheric Sciences Laboratory at Goddard, noted that
the new mosaic is the most detailed map of the continent
in existence and offers the most geographically accurate,
true-color views of the continent possible. "This
innovation, compared to what we had available most recently,
is like watching the most spectacular high-definition
TV in living color versus watching the picture on a small
black-and-white television,"he said.
An NSF grant provided the nearly $1 million U.S. contribution
to the LIMA project. Tom Wagner, earth sciences program
director for the NSF-managed U.S. Antarctic Program, noted
that this project is the first major scientific product
of the International Polar year (IPY).
"LIMA represents the true spirit of the IPY in two
ways," Wagner said. "Firstly, it's an international
collaboration between the U.S. and the United Kingdom,
and secondly, the map and raw data are freely available
to the world community of scientists, educators, and the
general public."
IPY is a coordinated international field campaign that
began in March 2007. During IPY, hundreds of scientists
from more than 60 nations will deploy to the Arctic and
Antarctic to study a range of disciplines. IPY marks the
beginning of a sustained effort to understand large-scale
environmental change in the Earth's polar regions. NSF
is the lead U.S. agency for IPY.
Wagner added that apart from the international collaboration
with the British Antarctic Survey, the project is a major
interagency collaborative, with both USGS and NASA playing
unique and key roles in bringing the map into existence,
and that the LIMA project grew out of a "grassroots"
scientific consensus across the government that the project
had merit.
Two researchers, Jerry Mullins, at USGS, and Bindschadler,
at NASA, he added, were instrumental in LIMA's development.
"Recognizing that change was afoot in the mapping
community, Jerry Mullins, with NSF's support, organized
a meeting of Antarctic researchers to determine their
needs for information about Antarctica. And it quickly
became apparent that LandSat imagery had great potential
but needed to be shaped into a new map for its potential
to be realized," Wagner said.
Wagner said that "Bob Bindschadler had the foresight
many years ago to convince NASA that the Landsat satellite
should collect data over Antarctica. His group also picked
all of the images that make up the mosaic. It wasn't easy
work; many thousands of scenes were considered and rejected.
New techniques to interpret the data were also developed
by Bob's group just for this project."
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NSF
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