- The Washington Times - Monday, April 22, 2002

LOS ANGELES (AP) A successful launch next month of an atmosphere-scanning satellite would mark the fourth spacecraft NASA has sent into orbit recently to follow the global movement of life's most precious resource: water.
The $952 million mission is scheduled for a May 2 launch from Vandenberg Air Force Base in California.
The satellite Aqua will follow the Jason 1 and a pair of twin spacecraft called Grace, launched in December and March, respectively.
Although each is different, their missions are designed to help piece together the puzzle of how water moves among the Earth's atmosphere, oceans and land.
"Each one of them is a critical element in this great hydrologic cycle, which really sustains life on Earth," said William Patzert, a National Aeronautics and Space Administration research oceanographer and scientist on the Jason 1 mission.
Scientists hope the three missions will lead to more accurate weather forecasts, better advance notice of El Ninos and a clearer understanding of how human activity affects the world.
Water and with it, energy moves through the world at varying paces before returning to the oceans that cover 70 percent of the planet. That cycle drives both climate and weather, in turn affecting life and its every activity.
Water lasts just days as a vapor in clouds, but it lasts weeks as a liquid in the world's rivers. As ice, it can remain locked in the polar caps for tens of thousands of years.
Monitoring the movement of water where, how quickly and in what phase it moves requires a global perspective, something scientists hope the flotilla of Earth-orbiting satellites can provide.
"The whole idea of the Earth is it's a closed system. So if you don't take global measurements, you can't model the whole thing," said Martin Mohan, who oversaw Aqua's development for Redondo Beach-based satellite builder TRW Inc.
Aqua, Latin for "water," and its six instruments will look almost exclusively at the hydrologic cycle, focusing primarily on the atmosphere.
Although the atmosphere holds just a sliver of all the world's water, that vapor is the most important greenhouse gas. As such, it also is the biggest unknown in gauging the effect of global warming and how it affects the hydrologic cycle, said Aqua project scientist Claire Parkinson.
"The hope is we will be able to get an indication of whether or not the cycling through the system is speeding up, staying steady or slowing down," he said. "The hypothesis is it might be speeding up."
Plans call for Aqua data to be plugged into daily weather forecasts, a first for NASA. It also will help keep tabs on droughts, hurricanes before they make landfall, and other markers that, together, suggest climate change.

LOAD COMMENTS ()

 

Click to Read More

Click to Hide