Portugal Colonial - NASA launches satellite for landmark study of Earth's water

The Surface Water and Ocean Topography (SWOT) satellite, a billion-dollar project jointly developed by NASA and France's space agency CNES, took off at 1146 GMT atop a SpaceX rocket from the Vandenberg Space Force Base.

According to a statement from NASA, it will start collecting scientific data in about six months after undergoing checks and calibrations.

"SWOT will bring us a revolutionary advance in our understanding of how water moves around our planet," said Karen St. Germain, NASA's Earth Science Division director, ahead of the launch.

"We will be able to see detail in eddies and currents and circulation in the oceans that we have never been able to see before."

She said this would help predict floods in areas with too much water, and manage water in regions prone to drought.

Selma Cherchali, of the French space agency CNES, told a press conference on Tuesday that the satellite represents a "revolution in hydrology. We are aiming to provide fine-scale observations ten times better than the current technology."

From a height of 890 kilometers (550 miles), SWOT will have the clearest view yet of the world's oceans, allowing it to track the rise in sea levels, as well as rivers and lakes.

Researchers will be able to get data on millions of lakes, rather than the few thousands currently visible from space.

"We know with climate change that Earth's water cycle is accelerating. What this means is that some locations have too much water, others don't have enough," said Benjamin Hamlington, a NASA research scientist.

"We're seeing more extreme droughts, more extreme floods, precipitation patterns are changing, becoming more volatile. So it's really important that we try to understand exactly what is happening."

The mission is meant to last for three and a half years, but could be extended until five years, or even more, said SWOT's project head at CNES, Thierry Lafon.

The US and French space agencies have worked together in the field for more than 30 years. A previous satellite developed by the partners, TOPEX/Poseidon, improved understanding of ocean circulation and its effect on global climate.

C.Amaral--PC