Steve Cole
Headquarters, Washington
202-358-0918
stephen.e.cole@nasa.gov
Alan Buis
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0474
alan.d.buis@jpl.nasa.gov
RELEASE: 11-317
AQUARIUS YIELDS NASA'S FIRST GLOBAL MAP OF OCEAN SALINITY
WASHINGTON -- NASA's new Aquarius instrument has produced its first
global map of the salinity of the ocean surface, providing an early
glimpse of the mission's anticipated discoveries.
Aquarius, which is aboard the Aquarius/SAC-D (Satelite de Aplicaciones
Científicas) observatory, is making NASA's first space observations
of ocean surface salinity variations - a key component of Earth's
climate. Salinity changes are linked to the cycling of freshwater
around the planet and influence ocean circulation.
"Aquarius' salinity data are showing much higher quality than we
expected to see this early in the mission," said Aquarius principal
investigator Gary Lagerloef of Earth & Space Research in Seattle.
"Aquarius soon will allow scientists to explore the connections
between global rainfall, ocean currents and climate variations."
The new map, which shows a tapestry of salinity patterns, demonstrates
Aquarius' ability to detect large-scale salinity distribution
features clearly and with sharp contrast. The map is a composite of
the data since Aquarius became operational on Aug. 25. The mission
was launched June 10 from Vandenberg Air Force Base in California.
Aquarius/SAC-D is collaboration between NASA and Argentina's space
agency, Comision Nacional de Actividades Espaciales (CONAE).
"Aquarius/SAC-D already is advancing our understanding of ocean
surface salinity and Earth's water cycle," said Michael Freilich,
director of NASA's Earth Science Division at agency headquarters in
Washington. "Aquarius is making continuous, consistent, global
measurements of ocean salinity, including measurements from places we
have never sampled before."
To produce the map, Aquarius scientists compared the early data with
ocean surface salinity reference data. Although the early data
contain some uncertainties, and months of additional calibration and
validation work remain, scientists are impressed by the data's
quality.
"Aquarius has exposed a pattern of ocean surface salinity that is rich
in variability across a wide range of scales," said Aquarius science
team member Arnold Gordon, professor of oceanography at Columbia
University in New York and at Lamont-Doherty Earth Observatory of
Columbia University in Palisades, N.Y. "This is a great moment in the
history of oceanography. The first image raises many questions that
oceanographers will be challenged to explain."
The map shows several well-known ocean salinity features such as
higher salinity in the subtropics; higher average salinity in the
Atlantic Ocean compared to the Pacific and Indian Oceans; and lower
salinity in rainy belts near the equator, in the northernmost Pacific
Ocean and elsewhere. These features are related to large-scale
patterns of rainfall and evaporation over the ocean, river outflow
and ocean circulation. Aquarius will monitor how these features
change and study their link to climate and weather variations.
Other important regional features are evident, including a sharp
contrast between the arid, high-salinity Arabian Sea west of the
Indian subcontinent, and the low-salinity Bay of Bengal to the east,
which is dominated by the Ganges River and south Asia monsoon rains.
The data also show important smaller details, such as a
larger-than-expected extent of low-salinity water associated with
outflow from the Amazon River.
Aquarius was built by NASA's Jet Propulsion Laboratory (JPL) in
Pasadena, Calif., and the Goddard Space Flight Center in Greenbelt,
Md., for NASA's Earth Systems Science Pathfinder Program. JPL is
managing Aquarius through its commissioning phase and will archive
mission data. Goddard will manage Aquarius mission operations and
process science data. CONAE provided the SAC-D spacecraft and the
mission operations center.
The new map is available at:
http://photojournal.jpl.nasa.gov/catalog/PIA14786 For more information about Aquarius/SAC-D, visit:
http://www.nasa.gov/aquarius http://www.conae.gov.ar/eng/principal.html
