April 30, 2009

NASA to measure ocean salinity from space

U.S. space agency scientists say they are preparing a satellite to measure the salinity of Earth's oceans.

The Aquarius satellite, to be launched during May 2010, will be the first National Aeronautics and Space Administration instrument to track sea salinity from space.

Sea saltiness today, as it has been for centuries, is measured by samples taken by ships' crews or, more recently, by automated buoys. But there are vast areas of the ocean where salinity has never been measured, NASA said. Although scientists know average sea levels have risen during the past century due to global warming, they don't know what climate change is doing to the salinity of the oceans.

This is an important question because big shifts in salinity could be a warning that more severe droughts and floods are on their way, or even that global warming is speeding up, NASA said.

People don't realize that there is so much water and so little land, said Amit Sen, NASA project manager for Aquarius at the Jet Propulsion Laboratory. He said Aquarius is expected to shed light on El Nino and La Nina, phases of the world's most powerful climate phenomena, reveal insights into how monsoons develop and how the oceans' salinity can change our lives.