International mission to measure saltiness of sea

Jun 06, 2011 By ALICIA CHANG , AP Science Writer
This image provided by NASA shows an artist's conception of the Aquarius/SAC-D spacecraft, a collaboration between NASA and Argentina's space agency, with participation from Brazil, Canada, France and Italy. Aquarius, the NASA-built primary instrument on the spacecraft, will take NASA's first space-based measurements of ocean surface salinity, a key missing variable in satellite observations of Earth that links ocean circulation, the global balance of freshwater and climate. (AP Photo/NASA)

(AP) -- An international mission will chart the saltiness of the ocean - from outer space.

An Argentine-built spacecraft carrying instruments from the United States and other nations is set to launch Thursday from the Vandenberg Air Force Base along the central California coast aboard a Delta 2 rocket.

The craft will circle 408 miles above the Earth and will use a NASA-built instrument to map weekly changes in the levels of brine in the sea. NASA's Aquarius instrument is so sensitive that it can detect changes down to a dash of in a gallon of water.

Nearly three-quarters of Earth's surface is covered by water, which contains about 3.5 percent salt. Though the amount of salt in the world's oceans remains mostly unchanged, the brine concentration in the topmost layer varies around the globe.

Understanding how brackish the sea surface is will help researchers better predict future climate change and short-term such as and its alter ego La Nina, which can have profound effects on weather around the world.

A fleet of Earth-orbiting satellites routinely provides updates on , sea level changes and ocean winds. But measurements of dissolved salts in the ocean so far have been limited, sporadically measured by ships and buoys.

"There are vast tracts of the ocean where salinity has never been collected - ever," NASA's Eric Lindstrom said at a pre-launch news conference.

The $287 million Aquarius - Latin for water-bearer and named after the constellation - is designed to measure microwave energy emitted by the ocean, giving scientists an idea of the saltiness. To prevent interference from radio, radar and other noise, another instrument will doublecheck the data and correct for any wrong readings.

Aquarius is expected to provide scientists with monthly maps depicting ocean salt variations over its three-year mission.

The project is a joint venture between NASA and Argentina's space agency CONAE. Other participating countries include Brazil, Canada, France and Italy, which will collect environmental data.

It's not the first to do ocean remote sensing of salt levels. Once in orbit, the spacecraft will join a dual-purpose European satellite that has been collecting data on ocean salt and soil moisture since 2009. Unlike the European mission, the new project is dedicated to the and uses different technology to make measurements. It's not unusual to have several overlapping Earth-observing satellites.

Scientists from both missions plan to combine data and compare results, said Gary Lagerloef of the Seattle-based nonprofit Earth & Space Research.

Explore further: Radioisotope studies show the continental crust formed 3 billion years ago

More information: Mission information:


Related Stories

Salt-seeking spacecraft arrives at launch site

Apr 01, 2011

( -- An international spacecraft that will take NASA's first space-based measurements of ocean surface salinity has arrived at its launch site at Vandenberg Air Force Base in California. The Aquarius/SAC-D ...

NASA ocean-watch satellite ready for June launch

May 17, 2011

The US space agency said Tuesday it is preparing to launch a satellite to observe levels of salt on the surface of the world's oceans and how changes in salinity may be linked to future climate.

Salt-seeking instrument blanketed in silver

Jan 25, 2011

( -- Technicians from NASA's Jet Propulsion Laboratory in Pasadena, Calif., completed the installation of thermal blankets on NASA's Aquarius instrument last week, as the Aquarius/Satelite de Aplicaciones ...

NASA's sea salt sensor to get cooked, chilled

Nov 24, 2010

While most Americans are traveling to family gatherings this week for Thanksgiving, a team of scientists from NASA's Jet Propulsion Laboratory, Pasadena, Calif., and the Goddard Space Flight Center in Greenbelt, ...

For NASA's Aquarius, quest for salt a global endeavor

Apr 07, 2011

( -- With more than a few stamps on its passport, NASA's Aquarius instrument on the Argentinian Satélite de Aplicaciones Científicas (SAC)-D spacecraft will soon embark on its space mission ...

Aquarius to illuminate links between salt, climate

May 12, 2011

When NASA's salt-seeking Aquarius instrument ascends to the heavens this June, the moon above its launch site at California's Vandenberg Air Force Base won't be in the seventh house, and Jupiter's latest alignment ...

Recommended for you

ESA image: Northwest Sardinia

Jul 03, 2015

This image over part of the Italian island of Sardinia comes from the very first acquisition by the Sentinel-2A satellite.

Experiments open window on landscape formation

Jul 02, 2015

University of Oregon geologists have seen ridges and valleys form in real time and—even though the work was a fast-forwarded operation done in a laboratory setting—they now have an idea of how climate ...

NASA image: Canadian wildfires continue

Jul 02, 2015

Canada is reeling from an early fire season this year as dozens of fires ravage at least three provinces of the country. All of the following reports are as of July 2, 2015.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.