NASA's New Studies of Earth's Seas, Skies and Soils
January 6, 2004
They're carbonated, salty, and alternately wet and dry. Exotic
champagnes? No, they're NASA's three Earth System Science Pathfinder
small-satellite program missions: Orbiting Carbon Observatory,
Aquarius and Hydros.
NASA has awarded all three of these fine "wines" gold medals of sorts
by authorizing them to proceed with mission formulation. Each
mission performs a first-of-a-kind exploratory measurement that will
help answer fundamental questions about how our planet works and how
it may change in the future. The Orbiting Carbon Observatory will
enhance our understanding of Earth's carbon cycle and climate.
Aquarius will examine the way oceans affect and respond to climate
change. Hydros will study how water, energy and carbon are exchanged
between land and Earth's atmosphere. NASA's Jet Propulsion
Laboratory, Pasadena, Calif., manages all three Earth System Science
Pathfinder missions for NASA's Earth Science Enterprise, Washington,
D.C.
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| Artist's concept of Hydros |
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"These three innovative missions have demonstrated they are ready to
use state-of-the-art remote sensing technology to observe and help us
understand the cycles of water, energy and carbon through Earth's
system. These are essential ingredients for sustaining life on
Earth, and NASA is using the power of space technology to understand
them," said Dr. Ghassem Asrar, NASA's associate administrator for
Earth Science. "NASA plans to negotiate contract awards for these
low-cost missions that address key scientific questions regarding how
Earth's atmosphere, oceans and land work together to shape our
weather, climate and environment," he said.
The Orbiting Carbon Observatory's two-year mission is targeted for
launch in August 2007. It will provide the first global, space-based
measurements of atmospheric carbon dioxide. The measurements will
have the precision to identify and monitor human and natural
processes responsible for absorbing and emitting this important
greenhouse gas, a fundamental building block for food, fiber and life
on Earth.
Precise ground-based measurements, collected since the 1970s,
indicate only about half of the carbon dioxide emitted into the
atmosphere by fossil fuel combustion has remained there. The land
and oceans have apparently absorbed the rest. However, ground-based
measurements are not adequate to determine how or where this
absorption is occurring. These uncertainties compromise our ability
to predict future atmospheric carbon dioxide concentrations or their
effect on the climate system.
Dr. David Crisp of JPL is principal investigator for the mission,
which includes more than 19 universities, corporate and international
partners.
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| Artist's concept of Aquarius |
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Aquarius's three-year mission, targeted for launch in September 2008,
is the first satellite mission specifically designed to provide
monthly global maps of how salt concentration varies on the ocean
surface. Variations in ocean surface salinity are a key area of
scientific uncertainty. Scientists wish to better understand how
these variations modify the interaction between ocean circulation and
the global water cycle, which, in turn, affects the oceans' capacity
to store and transport heat and regulate Earth's climate. The
mission seeks to determine how the ocean responds to the combined
effects of evaporation, precipitation, ice melt and river runoff on
seasonal and interannual time scales, and their impact on the global
distribution and availability of fresh water.
Dr. Gary Lagerloef of Seattle's Earth and Space Research is the
principal investigator. More than 17 universities, corporate and
international partners will be involved in the mission, including
Argentina's Comision Nacionales de Actividades Espaciales. NASA will
provide the Aquarius salinity sensor, project management, launch
services and science data processing. Argentina will provide the
spacecraft, additional instruments and mission operations.
Hydros will make unprecedented measurements of Earth's changing soil
moisture and the freeze/thaw status of land surface that, together,
define the state of Earth's hydrosphere. This state links the water,
energy and carbon cycles over land. Hydros measurements will open
new frontiers in our understanding of how these global cycles work
together in the Earth system. Numerical models used for day-to-day
weather prediction need soil moisture estimates as initial conditions
for forecasts. Incorporating real observations into these models
will significantly improve forecast accuracy. Soil moisture is among
the top terrestrial environment measurement requirements of the
Departments of Defense and Transportation because of the impact on
land navigation and aviation weather.
Contributing partners for the Hydros mission, in addition to NASA,
include the Canadian Space Agency and the Department of Defense. The
Hydros science team draws from several universities, NASA centers,
and research and operational branches of federal agencies. The
principal investigator is Dr. Dara Entekhabi of the Massachusetts
Institute of Technology, Cambridge, Mass.
JPL is managed for NASA by the California Institute of Technology in
Pasadena.
