PASADENA, California, April 25, 2002 (ENS) - Exactly what takes place as water circulates from the oceans through the atmosphere onto the land and back to the oceans again is the subject of a multi-million dollar, three country research project in space.

On May 4, the National Aeronautics and Space Administration (NASA) is set to launch satellite called Aqua that will carry instruments from three countries to monitor the global water cycle.

Aqua, Latin for water, is a NASA Earth Science satellite mission named for the large amount of information that the mission will be collecting about the Earth's water cycle. During its six year mission Aqua will monitor evaporation from the oceans, water vapor in the atmosphere, clouds, precipitation, soil moisture, sea ice, land ice, and snow cover on the land and ice.

NASA climatologist Dr. Claire Parkinson specializes in studying the role of sea ice in the global climate system. (Photo courtesy NASA)

In her positions on the American Meteorological Society's Committee on Polar Meteorology and Oceanography, on the Advisory Panel on Climate and Global Change for the National Oceanic and Atmospheric Administration, and on the Climate Research Committee of the National Academy of Sciences, Dr. Parkinson has found a need to integrate scientific information from a range of disciplines as the Aqua satellite is designed to do.

The school bus sized satellite is the latest sibling in a family of Earth Observing System satellites dedicated to studying Earth and expanding knowledge of global climate change. Equipped with six state-of-the-art instruments, Aqua will collect data on global precipitation, evaporation and the cycling of water.

"This comprehensive approach enables scientists to study the interactions among key elements of the Earth system so as to better understand our planet," Parkinson said.

Aqua is a joint project between the United States, Japan and Brazil. The United States provided the spacecraft and four of Aqua's six scientific instruments.

NASA's Goddard Space Flight Center provided the Moderate Resolution Imaging Spectroradiometer and the Advanced Microwave Sounding Unit. NASA's Jet Propulsion Laboratory in Pasedena provided the Atmospheric Infrared Sounder, and NASA's Langley Research Center in Hampton, Virginia, provided the Clouds and the Earth's Radiant Energy System instrument.

Japan's National Space Development Agency provided the Advanced Microwave Scanning Radiometer. The Brazilian Institute for Space Research provided the Humidity Sounder for Brazil.

This model of the Aqua satellite shows the side facing Earth where the instruments are mounted. (Image courtesy TRW Space and Electronics Group, Inc.)

"Aqua will provide unprecedented information on the global water cycle," said Dr. Ghassem Asrar, associate administrator for NASA's Earth Science Enterprise at NASA Headquarters, Washington, DC. "The spacecraft will enable operational agencies to create more accurate weather forecasts in the future."

Aqua is now at Vandenberg Air Force Base, California perched atop a Boeing Delta-7920-10L expendable launch vehicle. Launch is expected no earlier than May 4 at 2:55 am PDT.

Aqua will fly at an altitude of approximately 438 miles (705 kilometers) above the Earth in a near polar and sun synchronous orbit.

Aqua will make measurements of the Earth at the same time, all the time as the satellite orbits the planet on a nearly polar route, passing over different points on the ground at approximately 1:30 pm and 1:30 am.

By maintaining a consistent time for taking readings, the integrated suite of sensors on Aqua will allow sophisticated measurements of planetary processes that until now have been challenging to collect and calibrate.

Aqua project scientist Parkinson says, "NASA and its international partners are counting on this powerful observatory to help researchers explore not only how the Earth lives and breathes, but also how the people of the world can best care for the only planet in the solar system known to harbor life."conditioning and ore processing.