Washington: The US space agency on Friday launched a satellite to observe levels of salt on the surface of the world`s oceans and measure how changes in salinity may be linked to future climate.
The Aquarius/SAC-D spacecraft launched from Vandenberg Air Force Base in California at 7:20 am Pacific time (1420 GMT).
The orbiting science instrument will aim to map the entire open ocean every seven days from its position 408 miles (657 kilometers) above Earth, producing monthly estimates that show how salt levels change over time and location.
"The mission will survey the salinity levels at the surface of the ocean and seas and will complete the most detailed summary of conditions ever undertaken," NASA said.
"Until Aquarius, salt-content observations were mostly taken by ships traversing their trade routes. The information was incomplete, researchers say."
The mission to survey the world`s water surfaces is set to last for three years.
A European satellite was launched in 2009 to measure soil moisture and ocean salinity.
The Aquarius/SAC-D is a global collaboration with partner Argentina as well as France, Brazil, Canada and Italy, NASA said.
Earlier this year, NASA lost Glory, a $424 million Earth-observing satellite that failed to separate properly from its rocket launcher and plunged into the ocean.